# Multi-step gear

The invention concerns a multi-step transmission with at least 7 forward gears, with which transmission on the input drive shaft (1), two non-shiftable input-side gear sets (RS1, RS2) are provided, which, on their output-side produce two speeds of rotation (n1, n2), which, besides the speed of rotation of the input drive shaft (1), by selective closure of the shift elements (A, B, C, D, E) are shiftable in such a manner to one of the output-side planetary gear sets (RS3, RS4) which upon the output drive shafts (2), that for the shifting from one into the respective next following higher or lower gear of the two activated shift elements, respectively, only one shifting element must be open and a further element closed.

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**Description**

The present Application is a reissue of and claims benefit of U.S. patent application Ser. No. 10/089,808 filed Apr. 3, 2002 which is a national stage completion of PCT International Application Ser. No. PCT/EP00/09993 filed Oct. 11, 2000 which claims priority from German Patent Application Serial No. 199 49 507 filed Oct. 14, 1999.

**FIELD OF THE INVENTION**

The present invention concerns a multi-step transmission.

**BACKGROUND OF THE INVENTION**

Such a transmission has been disclosed by EP 0 434 525 A1, which encompasses, essentially, an input drive shaft and an output drive shaft, which are arranged coaxial to one another, a double planetary gear set placed concentric to the output drive shaft and five shifting elements in the form of three shift elements and two brakes, the selective blocking of which respectively determine, pairwise, the different gear ratios between the input drive shaft and the output drive shaft.

The known transmission possesses two power paths, wherein a first element of the double planetary gear set is connected by means of a first shift element with the first power path. A second element of the double planetary gear set is connected to the output drive shaft and a third element is connected with the second power path by means of a third shift element and is braked by means of a first brake. A fourth element of the double planetary gear set is connected with the first power path by means of a second shift element and is braked by a second brake, so that a selective shifting pairwise between the shifting organs assures that six forward gear positions are available. This arrangement then comprises a first gear through the first shift element and the first brake, a second gear through the first shift element and the second brake, a third gear through the first shift element and the second shift element, a fourth gear through the first shift element and the third shift element, a fifth gear through the second shift element and the third shift element a sixth gear through the third shift element and the second brake, and finally, a reverse gear position through the second shift element and the first brake.

**SUMMARY OF THE INVENTION**

The purpose of the present invention is to be found in the creating of a multi-step transmission, which encompasses at least seven forward gear positions with a favorable gear step and ample spread, and is relatively economical to manufacture.

An essential advantage is to be found in the fact, that the invented multi-step transmission offers at least seven forward gear positions with a reduced number of gear sets and shift elements. In each gear, into which a shift is made, only two shift elements are actuated. By the shifting from one gear to the next, simply one shift element was open and another shift element was closed. In this way, a GroupWise shifting of critical shifting quality, in which a plurality of shift elements must be shifted simultaneously, is avoided.

**BRIEF DESCRIPTION OF THE DRAWINGS**

The invention will now be described, by way of example, with reference to the accompanying drawings in which:

**DETAILED DESCRIPTION OF THE INVENTION**

In each figure are presented, in accordance with the respective embodiment of the invented multi-step transmission, the power flow schematic chart (

The following considerations lead to the invention. In order to create, with five shift elements, a multi-step transmission which is counter to the state of the technology and is relatively economical to manufacture, and that has seven forward gear positions and one reverse gear position, then, on the input drive shaft, two input-side gear sets must be provided. These two input-side gear sets, in addition to the speed of rotation “n” introduced by the input drive shaft, engender two further speeds of rotation n**1** and n**2**. Contrary to this, in the case of the known multi-step transmission described in the opening passages, only one input-side gear set is provided on the input drive shaft. This said input-side gear set, in addition to the input speed of rotation n produces one additional speed of rotation. By means of the activation of the shift elements, in the case of the present invention, the speeds of rotation n**1**, n**2** and the input speed of rotation n, corresponding to the shifted flow of power, are transferred to the output drive shaft. By means of placing additional shift elements, it becomes possible, utilizing the invented multi-step transmission with seven forward gear positions and one reverse gear position, to conceive of various multi-step transmissions with more than seven forward gear positions and at least one reverse gear position. This is true especially in the case of passenger motor vehicles, busses and trucks. For off-road vehicles a cross-country reduction gear can be designed with special gear staging. For the installation in motorcycles and bicycles, multi-gear drives without a reverse gear position can be made available.

In the following, in connection with

In the **1**, the shift elements are respectively denoted as A, B, C, D, and E. The first planetary gear set of the input-side gear set VS is designated with RS**1**, the second planetary gear set of that input-side gear set is RS**2**. In like manner, the first and second gear sets of the shiftable output-side gear set NS are designated RS**3** and RS**4**.

All five embodiments of the **1**, besides the input speed of rotation n of the input drive shaft **1**, generate a first additional speed of rotation n**1** and the second input-side gear set RS**2** produces a second supplementary speed of rotation n**2**. In each gear shifted to, in every case, only two shift elements are closed.

The input-side gear sets comprise a non-shiftable two carrier, 4-shaft drive, wherein at least one shaft, and as a maximum one shaft per input-side gear set runs with the speed of rotation of n of the input drive shaft and at least one shaft, and at a maximum, one shaft per input-side gear set is immobile.

The gear set RS**1** possesses a sun gear **11**, planet gears **12** and an internal gear **13**. The gear set RS**2** shows a sun gear **21**, planet gears **22** and an internal gear **23**. The planetary carrier designated as **15** is common to the planet gears **12** and the carrier designated with **25** is common to the planetary gear sets **22**.

In the case of the shiftable output-side gear sets NS, the arrangement is a shiftable two carrier, four shaft drive, which includes the planetary gear sets RS**3** and RS**4**. The gear set RS**3** has a sun gear **31**, planet gears **32** and an internal gear **33**. Correspondingly, the gear set RS**4** of the output-side drive NS comprises a sun gear **41**, planet gears **42**, and an internal gear **43**. The common carrier of the planet gears **32** is designated as **35** and the common carrier of the planet gears **42** is designated with **45**. The carrier **45** of the gear set RS**4** is connected with one shaft of the gear set RS**3**. Onto this coupling shaft, the shift elements E and D are affixed.

The shift elements B and C are connected to a central gear of the gear set RS**4**, wherein, by the term “central gear”, either a sun gear or an internal gear of the gear set is to be understood. The shift element A is connected to one central gear of the gear set RS**3**.

Either the shaft connected with the shift element A combined with the central gear of the gear set RS**4**—which is not connected with the shift elements B and C—forms the second coupling shaft (**2** (

For the speed of rotation of the shafts and shift elements, the following points are valid:

- 1. The speed of rotation on the input drive shaft and shift element E is n=1 (as a standard value),
- 2. The speed of rotation of the shift element D is greater than/equal to 0,
- 3. The speed of rotation of the shift element D is less than/equal to the speed of rotation at the shift element B,
- 4. The speed of rotation of the shift element C is less than the speed of rotation on the shift element B,
- 5. The speed of rotation of the shift element B is less than or equal to 1,
- 6. The speed of rotation of the shift element A lies in the range of 0 to 1,
- 7. As maximum, two running shafts in the output-side NS have the same speed of rotation,
- 8. The speeds of rotation introduced by the shifting elements A and D to the gear set RS
**3**, in connection with the gear ratio of the gear set RS**3**, produce an output drive shaft speed of rotation, which is greater than the output drive shaft speed of rotation, which is introduced by means of the shifting elements C and D onto the gear set RS**4**in connection with the gear ratio of the gear set RS**4**, and in the case, that the shaft connected with the shift element A forms a coupling shaft with a central gear of the gear set RS**4**of the shiftable output-side gear set NS, then, additionally with the gear ratio of the gear set RS**3**an output drive shaft speed of rotation is produced.

**1** is connected with the sun gears **11** and **21** of the input-side gear sets RS**1** and RS**2**. The internal gear **13** of the first input-side gear set RS**1** is stationarily fixed. The planetary carriers **15** and **25** of the two input-side gear sets RS**1** and RS**2** are connected together. The internal gear **23** (speed of rotation n**2**) of the second input-side gear set RS**2**, can be connected by means of the shift element D to the internal gear **33** of the first output-side gear set RS**3** and the carrier **45** of the second output-side gear set RS**4**. Further, the planetary carriers **15** and **25** (speed of rotation n**1**) can be connected by means of the shift element A with the sun gear **31** of the first output-side gear set RS**3**, as well as by means of the shift element C with the sun gear **41** of the second output-side gear set RS**4**. The input drive **1** is connectable by means of the shift element B to the sun gear **41** and to the carrier **45** by means of the shift element E. In the output-side gear sets NS, the carrier **35** of the gear set RS**3** is connected with the internal gear **43** of the gear set RS**4** and with the output drive shaft **2**. Besides this, the internal gear **33** of the gear set RS**3** is connected with the carrier of the gear set RS**4**.

The forward gear positions **1** to **7** and the reverse gear position R, with the aid of the control of the output-side gear set NS, i.e., the gear sets RS**3** and RS**4**, which respectively have the speeds of revolution of n, n**1** and n**2**, can be attained by means of selective shifting of the five shift elements A to E, in accord with the shift sketch of the

Advantageous in the embodiment 1 of the invented multi-step transmission, is especially the large spread (greater than 9) in the case of similar more favorable gear steps, which are described in the introductory passages as being state of the technology for 6-gear automatic transmissions. In this way, in the application example of a passenger car, for example, the normally installed torque converter, serving as a startup element, could be substituted for by a hydraulic shift element and/or a lamellar shift element integrated into the transmission without having to dispense with a high startup power. A possible embodiment is shown as an example in the

In the following, in connection with

The embodiment form **2**A has, contrary to the embodiment in

In the embodiment shown in **11** and **21** are connected with the input drive shaft **1**. By means of the shift element A, the input drive shaft **1** can be connected with the sun gear **31** and by means of the shift element E, also connected with the planetary carrier **45**. The planetary carrier **15** (speed of rotation n**1**) can be connected by means of the shift element B with the sun gear **41**. The internal gear **13** is connected with the carrier **25**, wherein the carrier **25** is rigidly affixed to the housing. The internal gear **23** (speed of rotation n**2**) can be connected with the sun gear **41** by means of the shift element C. The carrier **45** can be connected to the housing by means of brake D. The internal gear **33** is connected with the carrier **45**. The internal gear **43** is connected with the carrier **35** and with the output drive shaft **2**.

As is shown in the closed condition state of the five shift elements A to E the transmission shown in

Advantageous in the embodiment 2 of the invented multi-step transmission is especially the overdrive characteristic of the two upper gears, in regard to the reduction of fuel consumption and running noise. A further advantage is the designed simple formulation possibility of having a brake D instead of a shift element, for instance in regard to the delivery of pressurized oil for the activation.

The **1** is connected with the sun gear **11** of the gear set RS**1**, by means of the shift element E with the carriers **35**′. **35**″ of the inner and out planet gears **32**′, **32**″ of the gear set RS**2**, and can be connected with the carrier **45** of the gear set RS**4**. Further the input drive shaft **1** can be connected with sun gear **31** of the gear set RS**3** by means of the shift element A. The carriers **15**, **25**′, and **25**″, which are connected together, (speed of rotation n**1**) of the gear sets RS**1** and RS**2**, can be connected with the sun gear **41** of the gear set RS**4** by means of the shift element B. The planet gears **12** of the gear set RS**1** and the outer planet gears **22**″ of the gear set RS**2** are joined to one another. The sun gear **21** (speed of rotation n**2**) of the gear set RS**2** can be connected with the sun gear **41** of the gear set RS**4** by means of the shift element C. The internal gear **13** of the gear set RS**1** is immobilized. By means of the brake D, the carriers **35**′, **35**″ and **45** may be made stationary. The planet gears **42** of the gear set RS**4** and the outer planet gears **32**″ of the gear set RS**3** are coupled together. The output drive shaft **2** is rigidly bound to double internal gears **33** and **43**.

With the arrangement of

Advantageous in the embodiment 3 of the invented multi-step transmission is especially the favorable cost formulation of the four planetary gear sets with only two internal gears. Beyond this, the over-drive characteristic of the two upper gears can be employed for the saving of fuel and for a lessening of the noise emission.

**1** and n**2** are produced through the input-side gear sets RS**1** and RS**2**., whereby the carriers **15** and **25** of the planet gears **12** and **22** of this gear set are connected together. The input-side shaft **1** is connected with the internal gears **13** and **23** of the gear sets RS**1** and RS**2**, and by means of the shift element E can be connected with the internal gear **33** of the third gear set RS**3**, as well as being connectable by means of the shift element B with the internal gear **43** of the fourth gear set RS**4**. The sun gear **11** of the first gear set RS**1** is affixed to the housing. The sun gear **21** (speed of rotation n**2**) of the second gear set RS**2** can be connected by means of the shift element D to the carrier **45** of the gear set RS**4**, whereby the said carrier **45** is connected to the internal gear **33** of the gear set RS**3**. The carriers **15** and **25** (speed of rotation n**1**) of the planet gears **12** and **22** of the gear sets RS**1** and RS**2** can be connected by the shift element C with the internal gear **43** of the gear set RS**4**. The sun gears **31** and **41** of the gear set RS**3** and RS**4** can be blocked in common by the brake A. The carrier **35** of the gear set RS**3** is connected with the output drive shaft **2**.

The arrangement given in the schematic sketch of

The design **4** of the invented multi-step transmission is particularly favorable for use in off-road vehicles, since in this case, because of the stall-gear ratios of the gear sets, as shown in

In the design of the **13** is made immobile. The carrier **15** (speed of rotation n**1**) is connected with the carrier **25** and can be connected with the internal gear **43** by means of the shift element B. The internal gear **23** (speed of rotation n**2**) can be connected with the carrier **45** by means of the shift element D, and thus to the therewith connected internal gear **33**. The input drive shaft **1** is connected with the sun gears **11** and **21** and can be connected with the sun gears **41** and **31** by means of the shift element A, and further by the shift element E, can be connected with the carrier **45** and the internal gear **33**. In the case of the closed brake C and the open shift element B, the internal gear **43** can be adjusted to the speed of rotation zero. The carrier **35** is connected to the output drive **2**.

The exact closed conditions of the five shift elements A to E are obvious from **1** to **7** and for the reverse gear position R.

The design of the assembly **5** of the invented multi-step transmission is similar to the design structure **4**, in that it is especially favorable for off-road vehicles, since in this case, because of the stall gear ratios to be noted in the

The design presented in

In this case, the input drive shaft **1** (speed of rotation n) is connected with the internal gear **13** and the internal gear **23**. The said input drive shaft **1** can also be connected, by use of the shift element E, with combined carriers **45** of the gear set RS**4**, carrier **35**″ of the outer planet gears **32**″ of gear set RS**3** and carrier **35**′ of the inner planet gears **32**′ of the gear set RS**3**. The planet gears **32** and **42** are coupled together. The carrier **25** is connected with the carrier **15** (speed of rotation n**1**) and can be connected with the sun gear **41** by the shift element B. The sun gear **41**, upon the activation of the brake C, can be blocked, that is, connected to the housing. The carriers **15** and **25** (speed of rotation n**1**) can be connected with the sun gear **31** by the shift element A. The sun gear **21** (speed of rotation n**2**) can be connected by the shift element D with the carrier **35**′ of the inner planet gears **32**′ of the gear set RS**3** and can be connected by the shift element F with the sun gear **41** of the gear set RS**4**. The internal gears **33** and **43** are joined together and also are connected to the output drive shaft **2**.

In the case of these multi-step transmissions, it is possible, by closing the shift elements A to F, and in consideration of the stall ratios of the gear sets given in the table of **1** to S of the invented multi-step transmissions with seven forward gear positions. Advantageously, the gear steps can be designed to fit in a close space, which makes this particular arrangement particularly favorable for a vehicle with a diesel motor.

In the following, in connection with the **7**B, a multi-step transmission in accord with the invention will be described, which said transmission has two, coupled, non-shiftable input-side gear sets. In the case of these gear sets, shifting is available, by means of six shift elements A to F, through nine forward gear positions and two reverse gear positions.

The input drive shaft **1** is connected to the internal gear **13** of the input-side gear set RS**1** and the thereto connected internal gear **23** of the input-side gear set RS**2**. Further, the input drive shaft can be connected to the carrier **45** by means of the shift element E and by means of the shift element B, can be connected with the sun gear **41**. The carrier **25** of the planet gears **22** is connected with the carrier **15** (speed of rotation n**1**) as well as with the sun gear **31** by means of the shift element A. In addition, by the activation of the shift element F, the carrier **25** and the carrier **15** can be connected to the sun gear **41**. The sun gear **21** (speed of rotation n**2**) is connectable by the shift element C with the sun gear **41** as well as connectable with the carrier **45** by means of the shift element D. The carrier **45** is connected to the internal gear **33**. The internal gear **43** is connected with the carrier **35** and with the output drive shaft **2**.

With this described embodiment 7 of the invented multi-step transmission, it is possible, through selective closure of the shift elements A to F, as shown in the table of

The embodiment of the

In comparison to the multi-step transmission of the

Even though, in this case, the gear set RS**2** is minus one gear set, the gear set RS**1** is plus one gear set. The input drive shaft **1** is connected with the sun gear **21** as well as with the carrier **15**″ or the outer planet gears **22**″ of the gear set RS**1**, and by means of the shift element A can be connected with the sun gear **31** and by means of the shift element E, can be connected with the carrier **45**. The carrier **25** is, on the one hand, bound to the housing, and on the other side, connected with the sun gear **11** of the gear set RS**1**. The carrier **15**′ of the inner planet gear **12**′ is connected with the carrier **15**″ of the outer planet gears **12**″ of the gear set RS**1**. The internal gear **13** of the gear set RS**1** (speed of rotation n**1**) can be connected with the sun gear **41** by means of the shift element B. The internal gear **23** (speed of rotation n**2**) can be connected with the sun gear **41** through the shift element C. By the activation of the brake F, the sun gear **41** is connectable with the housing. The carrier **45**, upon the activation of the brake D, can be connected with the housing. Beyond this, the carrier **45** is connected to the internal gear **33**. The internal gear **43** connects with the carrier **35** and with the output drive shaft **2**.

The shifting logic for the six shift elements A to F for the shifting to the nine forward gears and the reverse gear position of the multi-step transmission in accord with

In a fortunate development, in the case of the embodiment 8 of the invented multi-step transmission, two shift elements are converted to brakes, whereby, advantages are brought about, relative to shift element construction, such as, for example, by a simple installation of the pressure oil channeling within the housing. Particularly advantageous is also the very harmonious gear stepping of the nine forward gear positions with almost continual, slowly occurring, gear stepping leading to the upper gears.

In the following, in connection with the **9**B, a further inventive multi-step transmission is explained, in which with a total of six shift elements A to F, eight forward gear positions and two reverse gear positions are available for shifting.

The special point of this transmission is, that only one, non-shiftable, input-side gear set RS**1** is present instead of two input-side gear sets as have been described up to this time. The input drive shaft **1** (speed of rotation n) is connected with the sun gear **11** of the gear set RS**1** (Plus-gear set), and can be connected with the carrier **45** by means of the shift element E, as well as being connectable by shift element B with the sun gear **41**. The carrier **15**′ of the inner planet gears **12**′ of the gear set RS**1** and the carrier **15**″ of the outer planet gears **12**″ of the gear set RS**1** are connected together and affixed to the housing. Moreover, the carrier **15**′ and the carrier **15**″, by means of the shift element C, can be connected with the sun gear **41**. The internal gear **13** (speed of rotation n**1**) can be connected with the sun gear **41** by the shift element F and also connected to the sun gear **31** by means of the shift element A. The internal gear **43** is connected to the internal gear **33** and connected to the output drive shaft **2**. The carrier **45** (of the planet gears **42**), carrier **35**′(of the inner planet gears **32**′) and carrier **35**″ (of the outer planet gears **32**″) are bound together and can be blocked by the brake D. The planet gears **32**″ and **42** are, in this case, also coupled.

The shifting logic of this multi-step transmission for the shifting into eight forward gear positions and two reverse gear positions by the closure of the shift elements A to F is tabulated in

Advantageously, in the case of the embodiment 9 of the invented multi-step transmission, besides the number of gears, is particularly the space saving and favorable costs associated therewith, since only three planetary gear sets with a total of two internal gears need be provided. The inter-gear stages are harmonic, where by, besides the “normal” reverse, also a “quicker” reverse gear position can be shifted into, similar to that of the embodiment 7.

The **1**, RS**2**a and RS**2**b, by means of seven shift elements A to G, shifting is available through thirteen forward gear positions and one reverse gear position. On the shaft with the shift elements B, C and F, an additional shift element G has been provided. Thus, the valid relationship is NF>nG>Nb. In input speeds of rotation are produced through a non-shiftable three carrier, five shaft gear arrangement.

The input drive shaft **1** (speed of rotation n) is bound to the sun gear **11** of the first input-side gear set RS**1** and can be connected by means of the shift element A with the sun gear **31** of the first output-side gear set RS**3** and the thereto connected sun gear **41** of the second output-side gear set RS**4** and can be connected further by means of the shift element E with the carrier **45** of the second output-side gear set RS-**4**.

The gear set RS**2**, which has been installed in the described transmissions up to this point, is now replaced by the gear sets RS**2**a and RS**2**b, whereby, the carriers **25**a and **25**b″ of the planet gears **22**a of the gear set RS**2**a and the outer planet gears **22**b″ of the plus-transmission constructed gear set RS**2**b are all connected together. The planet gears **22**a and **22**b″ are coupled together. The carrier **15** is connected to the carriers **25**b′ of the inner planet gears **22**b′ and to the carrier **25**b″ of the outer planet gears **22**b″. Beyond this the carrier **25**b″ can be connected with the internal gear **43** (speed of rotation n**2**a) by means of the shift element G. The internal gear **43** can be blocked by the brake C. The sun gear **21**a of the gear set RS**2**a (speed of rotation n**1**) can be connected with the internal gear **43** by means of the shift element B. The internal gear **23**a of the gear set RS**2**a and the internal gear **23**b of the gear set RS**2**b are connected together (speed of rotation n**2**b) and can be connected with the internal gear **43** by means of the shift element F, and by the shift element D can be connected with the carrier **45** and the therewith attached internal gear **33**. The carrier **35** is connected to the output drive shaft **2**. Finally, the sun gear **21**b of the gear set RS**2**b and the internal gear **13** of the gear set RS**1** are connected with the housing.

With this described multi-step transmission, it is possible, through selective closure of the seven shift elements A to G, in combination with the tabulated stall ratios as presented in the table of

The advantages of this embodiment 10 of the invented multi-step transmission lie thus in the high number of gear changes along with a very compact installation space with only five planetary gear sets and seven shift elements. By means of a selected choice of the gear ratios of the gear sets, from the embodiment 10, a multi-step transmission with two reverse gear positions can be developed, but then with only twelve forward gear positions.

In the embodiment of the invented multi-step transmission shown in

The input-side gear set VS comprises, in total, four connected, non-shiftable planet gear sets. The input-side gear set RS**1** consists of a gear set RS**1**a and a gearset RS**1**b, wherein the planet gears **12**a of the gear set RS**1**a and the outer planet gears **12**b″ of the gear set RS**1**b are coupled together and the carrier **15**b″ of the outer planet gears **12**b″ is connected with the carrier **15**b′ of the inner planet gears **12**b′. The gear set RS**2** encompasses two gears sets RS**2**a and RS**2**b, whereby the planet gears **22**a of the gear set RS**2**a and the outer planet gears **22**b″ of the gear set RS**2**b are coupled together.

The input drive shaft **1** (speed of rotation **1**) is connected with the sun gear **11**b of the gear set RS**1**b and the sun gear **21**a of the gear set RS**2**a and by means of the shift element A can be connected with the sun gear **31** and by means of the shift element E is connectable with the internal gear **33**. The sun gear **11**a of the gear set RS**1**a is connected with the housing. The internal gear **13**a of the gear set RS**1**a and **13**b of the gear set RS**1**b are connected to one another (speed of rotation, n**1**a) and by means of the shift element B can be connected to the sun gear **41** of the second output-side gear set RS**4**. The sun gear **41** is blockable by the brake C. The sun gear **21**b of the gear set RS**2**b (speed of rotation n**2**B) can be connected to the internal gear **33** by means of the shift element D, as well as with the sun gear **41** by means of the shift element F. The internal gear **33** is connected to the carrier **45**. The carrier **25**b′ of the inner planet gears **22**b′ and **25**b″ of the outer planet gears **22**b″ of the gear set RS**2**b and the carrier **25**a of the gear set RS**2**a are bound to one another (speed of rotation n**1**b) and can be connected to the sun gear **41** by means of the shift element H. The coupled internal gears **23**a and **23**b (speed of rotation n**2**a) of the gear sets RS**2**a and RS**2**b can, likewise, be connected to the sun gear **41** by means of the shift element G. The sun gear **43** is connected with the carrier **35** and with the output drive shaft **2**.

With these described gear arrangements, the tables presented in

In the following, in connection with the **1**, which is achieved in that the previously mentioned kinematic condition “speed of rotation on the shift element D is less than, or equal to the speed of rotation on the shift element B” is limited by the change, “speed of rotation on the shift element D is equal to the speed of rotation on the shift element B”.

The internal gear **13** of the input-side gear set RS**1** is rigidly connected by means of an axle with the housing of the multi-step transmission. The input drive shaft **1** (speed of rotation n) is connected with the sun gear **11** of the input-side gear set RS**1**. The said input drive shaft **1** is connectable by means of the shift element E with the internal gear **33** of the first output-side gear set RS**3** as well as with the therewith connected carrier **45** of the second output-side gear set RS**4**. Additionally, by means of the shift element A the input drive shaft **1** can be connected to the sun gear **31** of the gear set RS**3**. The carrier **15** (speed of rotation n**1**) of the gear set RS**1** is connectable with the sun gear **41** of the gear set RS**4** through the shift element B and can further be connected with the internal gear **33** of the gear set RS**3** by means of the shift element D. By means of the brake C, the sun gear **41** of the gear set RS**4** can be immobilized. The internal gear **43** of the gear set RS**4** and the therewith connected carrier **35** of the gear set RS**3** are connected with the output-side shaft **2**.

With this just described transmission the possibility arises that by selective closure of the shift elements A through E, as indicated in the table of

In the following, and referring to

In this transmission, likewise, a single input-side gear set RS**1** is provided, which produces the necessary speed of rotation for the regulation of the output-side gear sets RS**3** and RS**4**. The input-side gear set RS**1** possesses, besides a sun gear **11** and an internal gear **13**, inner planet gears **12**′ and outer planet gears **12**″, the carriers of which (**15**′ and **15**″) are connected together.

The input drive shaft **1** (speed of rotation n) is connected to the sun gear **11** of the input-side gear set RS**1** and can be connected with the carrier **35**″ of the outer planet gears **32**″ of the first output-side gear set RS**3** by means of the shift element E, as well as connectable through the shift element A with the sun gear **31** of the gear set RS**3**. The carriers **15**′ and **15**″ of the gear set RS**1** are affixed to the housing of the multi-step transmission. The sun gear **41** of the gear set RS**4** can be blocked by the brake C. The internal gear **13** (speed of rotation n**1**) of the gear set RS**1**, by means of the shift element B, is connectable with the sun gear **41** and by means of the shift element D also connectable with the carrier **35**′ of the inner planet gears **32**′ of the gear set RS**3**. The carrier **35**′ is connected to the carrier **35**″ of the outer planet gears **32**″ of the gear set RS**3** and connected also with the carrier **45** of the gear set RS**4**. The planet gears **32**″ and **42** are, in this arrangement, coupled with one another. The internal gears **33** and **43** of gear sets RS**3** and RS**4** are connected with the output drive shaft **2**.

It is possible, with this described transmission, by means of selective closure of the shift elements A through E, as shown in the table of

In the following, in connection with

The sun gear **11** of the input-side gear set RS**1** is affixed to the housing of the multi-step transmission. The input drive shaft **1** (speed of rotation n) is connected with the internal gear **13** of the gear set RS**1** and by means of the shift element E can be brought into connection with carrier **45** of the second output-side gear set RS**4** along with the therewith connected sun gear **31** of the first output-side gear set RS**3**. In like manner, through shift element A the input drive shaft **1** (speed of rotation n) can be brought into connection with the internal gear **33** of the gear set RS**3** and the therewith connected internal gear **43** of the gear set RS**4**. The carrier **15** (speed of rotation n**1**) of the gear set RS**1**, by means of the shift element B, can be connected with the sun gear **41**, and by means of the shift element B, can be connected with the sun gear **41** and by means of the shift element D connectable with the carrier **45** of the gear set RS**4**. Use of the brake C permits the sun gear **41** of the gear set RS**4** to be made immobile. The carrier **35** of the gear set RS**3** is connected to the output drive shaft **2**.

By selective choice of closure of the shift elements A to E, in this described transmission, as seen in the tabulation of

In an advantageous manner, with the embodiments 12, 13 and 14 of the invented multi-step transmission a total of eight forward gear positions is achieved with only three sets of planetary gears and five shift elements. Especially on the account of extremely compact transmission construction and dispensing with the reverse gears, these embodiments 12, 13, and 14 are particularly appropriate for motorcycles and as a hub-shifting mechanism for bicycles. For application in a motorcycle, the gear stages of the embodiment 12 are advantageous, since in this case, the two higher gear positions exhibit a type of over-drive characteristic. For the use in bicycles the closely stepped stages in mid-range, in connection with the increasing step spread as the lower stages are approached makes the embodiments 13 and 14 particularly attractive.

In the following, in connection with the

The second input-side gear set RS**2** is designed as a plus-gear set and the first input-side gear set RS**1** is designed as a minus-gear set, wherein the outer planet gears **22**″ of the gear set RS**2** are rigidly coupled to planet gears **12** of the gear set RS**1**. The input drive shaft **1** (speed of rotation n) is connected to the sun gear **21** of the gear set RS**2**, as well as, connectable to the sun gear **41** through the shift element B and can further be connected by the shift element E to the carrier **45** of the second output-side gear set RS**4**, wherein the carrier **45** is connected with the internal gear **33** of the first output-side gear set RS**3**. The carrier **15** (speed of rotation n**1**) common to the outer planet gears **22**″ of the gear set RS**2** and the planet gears **12** of the gear set RS**1**, can be connected to the sun gear **31** of the gear set RS**3** by means of shift element A and can be connected to the sun gear **41** of the gear set RS**4** through shift element F. Beyond this, the carrier **15** is connected with the carriers **25**″ of the outer planet gears **22**″ and **25**′ of the inner planet gears **22**′ of the gear set RS**2**. The coupled internal gears **13** and **23** (speed of rotation n**2**) of the gear sets RS**1** and RS**2** can be connected through the shift element D with the carrier **45** as well as being connected to the sun gear **41** of the gear set RS**4** by means of the shift element C. The carrier **35** of the gear set RS**3** is connected to the internal gear **43** of the of the gear set RS**4** and with the output drive shaft **2**.

With this multi-step transmission, by selective closure of the shift elements A to F in the manner shown in the table of

Finally, in connection with the **11**A, there are provided here, all together, four coupled, non-shiftable, input-side gear sets. The input-side gear set RS**1** comprises in this arrangement, a gear set RS**1**a and a gear set RS**1**b, the input-side gear set RS**2** is made up of a gear set RS**2**a and a gear set RS**2**b.

The input drive shaft **1** is connected with the sun gear **11**a of the first input-side gear set RS**1**a (plus-gear set) and can be connected to the sun gear **31** of the first output-side gear set RS**3** by means of activating shift element A. Shift element E can connect the input drive shaft **1** to the carriers **35**′ of the inner planet gears **32**′ and **35**″ of the outer planet gears **32**″ of the gear set RS**3** (plus-gear set). The carrier **15**a′ of the inner planet gears **12**a″ of the gear set RS**1**a and the carrier **15**″ of the outer planet gears **12**″ of the gear set RS**1** are joined together. The gear set RS**1**b is designed as a minus gear train. In this arrangement, the sun gear **11**b of the second input-side gear set RS**1**b corresponds to the sun gear **21**a of the third input-side gear set RS**2**A. Further the internal gear **13**b of the second gear set RS**1**b corresponds to the internal gear **23**b of the fourth input-side gear set RS**2**b. The outer planet gears **12**a″ of the gear set RS**1**a, the planet gears **12**b of the gear set RS**1**b, the planet gears **22**a of the gear set RS**2**a and the planet gears **22**b of the gear set RS**2**b are coupled together as stepping planetary gears. To these, the carrier **15**a″ is assigned in common. The carrier **15**a″ (speed of rotation n**1**b) is, upon activation of the shift element G, connectable with the sun gear **41** of the second output-side gear set RS**4** (minus gear train) as well as, upon activation of the shift element D, connectable to the carrier **35**′ of the inner planet gears **32**′ of the first output-side gear set RS**3**. The gear set RS**3** is designed as a plus gear train. The outer planet gears **32**″ of the gear set RS**3** are coupled with the planet gears **42** of the gear set RS**4**. The carrier **35**′ of the inner planet gears **32**′ is connected to the carrier **35**″ of the outer planet gears **32**″ of the gear set RS**3**. The sun gear **11**b of the gear set RS**1**b is affixed to the housing. The sun gear **21**b of the gear set RS**2**b (speed of rotation n**2**b) is, by activation of the shift element F, connectable with the sun gear **41**, which, by means of the brake C is likewise affixed to the housing. The internal gear **13**a of the gear set RS**1** and **13**b of the gear set RS**1**b are connected together and, upon activation of the shift element B (speed of rotation n**1**a) are connectable to the sun gear **41**. The carrier **35**″ and the carrier **35**′ are connected together with the carrier **45**. The internal gear **23**a of the, gear set,RS**2**a (speed of rotation n**2**a) is, through the shift element H, connectable with the sun gear **41** of the gear set RS**4**. Finally, the internal gears **33** and **43** are connected with the output drive shaft **2**.

With the described features of the multi-step transmission, and with consideration of the table in

Similar to the embodiments 12, 13, 14, the described embodiments 15 and 16 of the multi-step transmissions are particularly adaptable to motorcycles and especially well suited for hub shifting for bicycles, with a corresponding high number of shift positions.

^{th }shifting element (shift element or brake)

## Claims

1. A multi-step transmission, with an input drive shaft (1) which is connected with an input-side gear set (VS), with, an output drive shaft (2) which is connected with an output-side gear set (NS) which is comprised of two shiftable, coupled planetary gear sets (RS3, RS4), and with shift elements (A-H), whereby by chosen shifting of the said shift elements (A-H) the speed of rotation of the input drive shaft (1) and the speed of rotation of the input-side gear set (VS) are transferable selectively to the output-side gear set for the shifting of gear positions, wherein the input-side gear set (VS) is constructed of two non-shiftable, coupled planetary gear sets (RS1, RS2), whereby the two planetary gear sets (RS1, RS2) produce for their output-side two speeds of rotation (n1, n2), which, besides the input speed of rotation (n) of the input drive shaft (1), optionally, on at least one of the two shiftable planetary gear sets (RS3, RS4) of the output-side gear set (NS), which act upon the output drive shaft (23), by means of selective closure of the shift elements (A-F H) are shiftable in such a manner, that for the shifting from one gear position into the subsequent higher or lower gear position, of the two just activated shift elements, respectively only one shift element is shut off and a further shift element is activated, and in that at least at least seven forward gear positions are made available.

2. The multi-step transmission according to claim 1, wherein the number of the forward gear positions is about twice as large as the number of the shift elements (A-F H).

3. The multi-step transmission according to claim 1, wherein as an input-side gear set (VS) a first planetary gear set (RS1) and a second planetary gear set (RS2) are provided, which form a non-shiftable two carrier, four shaft, gear set, whereby at least one shaft runs with the input speed of rotation (n) of the input drive shaft (1) and a further shaft is stationary, and in that the shiftable output-side gear set (NS) is a shiftable, two carrier, four shaft gear drive, which incorporates a third planetary gear set (RS3) and a fourth planetary gear set (RS4).

4. The multi-step transmission according to claim 1, wherein the sun gear 11 of the first planetary gear set (RS1) and the sun gear (21) of the second planetary gear set (RS2) are placed on the input drive shaft (1), in that the internal gear (13) of the first planetary gear set (RS1) is rendered immobile, and in that the carrier (15) of the planetary gears (12) of the first planetary gear set (RS1) is connected with carrier (25) of the planet gears (22) of the second planetary gear set (RS2), in that the internal gear (23) of the second planetary gear set (RS2), by means of fourth shift element (D) can be connected to the internal gear (33) of the third planetary gear set (RS3), in that the internal gear (33) of the third planetary gear set (RS3) is connected to the carrier (45) of the planet gears (42) of the fourth planetary gear set (RS4), in that the carrier (15) of the first planetary gear set (RS1), by means of a first shift element (A) can be made connectable with the sun gear (31) of the third planetary gear set (RS3), in that the carrier (25) of the second planetary gear set (RS2), by means of the third shift element (C) can be made connectable with the sun gear (41) of the fourth planetary gear set (RS4), in that the carrier (35) of the planet gears (32) of the third planetary gear set (RS3) is connected with the internal gear (43) of the fourth planetary gear set (RS4) and with the output drive shaft (2), in that the input drive shaft (1), by means of a second shift element (B) can be made connectable with the sun gear (41) of the fourth planetary gear set (RS4) and by means of a fifth shift element (E) also connectable with the carrier (45) of the fourth planetary gear set (RS4) (See FIG. 1A).

5. The multi-step transmission according to claim 1, wherein the input drive (1) is connected to the sun gear (11) of the first planetary gear set (RS1) and to the internal gear (21) of the second planetary gear set (RS2), in that the carrier (25) of the planet gears (22) of the second planetary gear set (RS2) is rendered immobile and is connected to the internal gear (13) of the first planetary gear set (RS1), in that the input drive shaft (1), by means of a first shift element (A) is connectable with the sun gear (31) of the third planetary gear set (RS3) and by means of a fifth shift element (E) is connectable to the carrier (45) of the planet gears (42) of the fourth planetary gear set (RS4), in that the carrier (45) of the fourth planetary gear set (RS4) is connected to the internal gear (33) of the third planetary gear set (RS3), in that the carrier (45) of the fourth planetary gear set (RS4) and the therewith connected internal gear (33) of the third planetary gear set (RS3), by means of a fourth shift element (D) can be immobilized, in that the internal gear (23) of the second planetary gear set (RS2), by means of the third shift element (C) is made connectable with the sun gear (41) of the fourth planetary gear'set (RS4), in that the carrier (15) of the planet gears (12) of the first planetary gear set (RS1), by means of a second shift element (B) is made connectable with the sun gear (41) of the fourth planetary gear set (RS4) and in that the internal gear (42) of the fourth planetary gear set (RS4) is connected to the carrier (35) of the third planetary gear set (RS3) and is also connected to the output drive shaft (2) (See FIG. 2A).

6. The multi-step transmission according to claim 1, wherein the input drive shaft (1) is connected with the sun gear (11) of the first planetary gear set (RS1), in that the carrier (15) of the planet gears (12) of the first planetary gear set (RS1) is connected to carrier (25″) of the outer planetary gear set (22″) and also to the carrier (25′) of the inner planet gears (22′) of the second planetary gear set (RS2), in that the inner planet gears (12) of the first planetary gear set (RS1) are coupled with the outer planet gears (22′) of the second planetary gear set (RS2), in that the internal gear (13) of the first planetary gear set (RS1) is connected with internal gear (23) of the second planetary gear set (RS2), in that the internal gear (13) of the first planetary gear set (RS1) is made immobile, in that the carrier (35″) of the outer planet gears (32″) of the third planetary gear set (RS3)is connected with the carrier (35′) of the inner planet gears (32′) of the third planetary gear set (RS3) and with the carrier (45) of the planet gears (42) of the fourth planetary gear set (RS4), in that the two carriers (35′, 35″) of the third planetary gear set (RS3) and the therewith connected carrier (45) of the fourth planetary gear set (RS4), by means of a fourth shift element (D) can be made immobile, in that the input drive shaft (1), by means of a first shift element (A) is connectable with the sun gear (31) of the third planetary gear set (RS3), in that the input drive shaft (1), by means of a fifth shift element (E) can be made connectable with the carriers (35′, 35″) of the third planetary gear sets (RS3) and with the therewith connected carrier (45) of the fourth planetary gear set (RS4), in that the planet gears (42) of the fourth planetary gear set (RS4) are coupled to the outer planet gears (32″) of the third planetary gear set (RS3), in that the sun gear (21) of the second planetary gear set (RS2), by means of a third shift element (C) is connectable with sun gear (41) of the fourth planetary gear set (RS4), in that the carrier (15) of the first planetary gear set (RS1) and the two therewith connected carriers (25′, 25″) of the second planetary gear set (RS2), by means of a second shift element (B) can be made connectable with the sun gear (41) of the fourth planetary gear set (RS4) and in that the internal gear (33) of the third planetary gear set (RS3) and the thereon coupled internal gear (43) of the fourth planetary gear set (RS4) are connected with the output drive shaft (1), (See FIG. 3A).

7. The multi-step transmission according to claim 1, wherein the planet gears (12) of the first planetary gear set (RS1) are coupled onto the planet gears (22) of the second planetary gear set (RS2), in that the sun gear (11) of the first planetary gear set (RS1) is made immobile, in that the carrier (15) of the planet gears (12) of the first planetary gear set (RS1) and the carrier (25) of the planet gears (22) of the second planetary gear set (RS2) are connected with one another, in that the input drive shaft (1) is connected with the internal gear (13) of the first planetary gear set (RS1) and with the internal gear (23) of the second planetary gear set (RS2), in that the sun gear (21) of the second planetary gear set (RS2), by means of a fourth shift element (D) is connectable with the carrier (45) of the planetary gears (42) of the fourth planetary gear set (RS4), in that the carrier (15) of the first planetary gear set (RS1) and the therewith connected carrier (25) of the second planetary gear set (RS2), by means of a third shift element (C) are connectable with the internal gear (43) of the fourth planetary gear set (RS4), in that the input drive shaft (1), by means of a second shift element (B) is connectable with the internal gear (43) of the fourth planetary gear set (RS4), in that the input drive shaft (1), by means of a fifth shift element (E) is connectable with the internal gear (33) of the third planetary gear set (RS3), in that the internal gear (33) of the third planetary gear (RS3) is connected to the carrier (45) of the fourth planetary gear (RS4) in that the carrier (35) of the planet gears (32) of the third planetary gear set (RS3) is connected with the output drive shaft (2) and in that the sun gear (31) of the third planetary gear set (RS3) and the sun gear (41) of the fourth planetary gear set (RS4) are bound together and by means of a first shift element (A) can be made immobile. (See FIG. 4A).

8. The multi-step transmission according to claim 1, wherein the input drive shaft (1) is connected with the sun gear (11) of the first planetary gear set (RS1), in that the sun gear (11) of the first planetary gear set (RS1) is connected with the sun gear (21) of the second planetary gear set (RS2), in that the internal gear (11) of the first planetary gear set (RS1) is made immobile, in that the carrier (15) of the planet gears (12) of the first planetary gear set (RS1) is connected with the carrier (25) of the planet gears (22) of the second planetary gear set (RS2), in that the internal gear (23) of the second planetary gear set (RS2), by means of a fourth shift element (D) can be connected with the carrier (45) of the fourth planetary gear set (RS4), in that the carrier (45) of the fourth planetary gear set (RS4) is connected with the internal gear (33) of the third planetary gear set (RS3), in that the input drive shaft (1), by means of a first shift element (A) is connectable with the sun gear (31) of the third planetary gear set (RS3) and the therewith connected sun gear (41) of the fourth planetary gear set (RS4), in that the input drive shaft (1), by means of a fifth shift element (E) is connectable to the carrier (45) of the fourth planetary gear set (RS4) and to the therewith coupled internal gear (33) of the third planetary gear set (RS3), in that the carrier (15) of the first planetary gear (RS1) and the therewith connected carrier element (B) is connectable with the internal gear (43) of the fourth planetary gear set (RS4), in that the internal gear (43) of the fourth planetary gear set (RS4), by means of a third shift element (C) can be made immobile, and in that the carrier connected to the output drive shaft (2), (See FIG. 5A).

9. The multi-step transmission according to claim 1, wherein the input shaft drive (1) is connected with the internal gear (13) of the first planetary gear set (RS1), in that the internal gear (13) of the first planetary gear set (RS1) is connected with internal gear (23) of the second planetary gear set (RS2), in that the sun gear (11) of the first planetary gear set (RS1) is made immovable, in that the carrier (15) of the planetary gear set (12) of the first planetary gear set (RS1) is connected with the carrier (25) of the planet gears (22) of the second planetary gear set (RS2), in that the sun gear (21) of the second planetary gear set (RS2), by means of a fourth shift element (D) is connectable with the carrier (35′) of the inner planet gears (32′) of the third planetary gear set (RS3), in that the carrier (35′) of the inner planet gear (32′) of the third planetary gear set (RS3) is connected with the carrier (35″) of the outer planet gears (32″) of the third planetary gear set (RS3), in that the outer planet gears (32″) of the third planetary gear set (RS3) are coupled with the planet gears (42) of the fourth planetary gear set (RS4), in that the carrier (25) of the second planetary gear set (RS2), by means of a first shift element (A) is connectable with the sun gear (31) of the third planetary gear set (RS3), in that the input drive shaft (1), by means of a fifth shift element (E) is connectable with the carrier (35′) and with the carrier (35″) of the third planetary gear set (RS3), in that the sun gear (21) of the second planetary gear set (RS2), by means of a sixth shift element (F) is connectable with the sun gear (41) of the fourth planetary gear set (RS4), in that the carrier (15) of the first planetary gear set (RS1) and the carrier (25) of the second planetary gear set (RS2), by means of a second shift element (B) are connectable with the sun gear (41) of the fourth planetary gear set (RS4), in that the sun gear (41) of the fourth planetary gear set (RS4), by means of a third shift element (C) can be made immovable, in that the internal gear (33) of the third planetary gear set (RS3) is connected to internal gear (43) of the fourth planetary gear set (RS4) and is also connected to the output drive shaft (2), (See FIG. 6A).

10. The multi-step transmission according to claim 1, wherein the input drive shaft (1) is connected with the internal gear (13) of the first planetary gear set (RS1), in that the carrier (15) of the planet gears (12) of the first planetary gear set (RS1) is connected with the carrier (25) of the planet gears (22) of the second planetary gear set (RS2), in that the internal gear (13) of the first planetary gear set (RS1) is connected with the internal gear (23) of the second planetary gear (RS2), in that the sun gear (11) of the first planetary gear set (RS1) is made immobile, in that the input drive shaft (1), by means of a fifth shift element (E) is connectable with the carrier (45) of the planet gears (42) of the fourth planetary gear (RS4), which is connected to the internal gear (33) of the third planetary gear set (RS3), in that the input drive shaft (1), by means of a second shift element (B) is connectable with the sun gear (41) of the fourth planetary gear set (RS4), in that the carrier (15) of the first planetary gear set (RS1) and the carrier (25) of the second planetary gear set (RS2), by means of a first shift element (A) are connectable with the sun gear (31) of the third planetary gear set (RS3) and by means of a sixth shift element (F) are connectable with the sun gear (41) of the fourth planetary gear set (RS4), in that the sun gear (21) of the second planetary gear set (RS2), by means of a third shift element (C) is connectable with the fourth planetary gear set (RS4) and by means of a fourth shift element (D) is connectable with the carrier (45) of the fourth planetary gear set (RS4) and also with the internal gear (33) of the third planetary gear set (RS3) and in that the internal gear (43) of the sun gear (41) of the fourth planetary gear set (RS4) is connected to the carrier (35) of the planet gears (32) of the third planetary gear set (RS3) and also with the output drive shaft (2), (See FIG. 7A).

11. The multi-step transmission according to claim 1, wherein the input drive shaft (1) is connected with the sun gear (21) of the second planetary gear set (RS2) and also connected with the carrier (15′) of the inner planet gears (12′) of the first planetary gear set (RS1), in that the carrier (15′) of the inner planet gears (12′) of the first planetary gear set (RS1) is connected with the carrier (15″) of the outer planet gears (12″) of the first planetary gear set (RS1), in that the carrier 25 of the planet gears (22) of the second planetary set (RS2) are made immobile and connected with the sun gear (11) of the first planetary gear set (RS1), in that the input drive shaft (1) by means of a first shift element (A) is connectable with the sun gear (31) of the third planetary gear set (RS3), in that the internal gear (23) of the second planetary gear set (RS2) by means of a third shift element (C) is connectable with the sun gear (41) of the fourth planetary gear set (RS4), in that the internal gear (13) of the first planetary gear set (RS1), by means of a second shift element (B) is connectable with the sun gear (41) of the fourth planetary gear set (RS4), in that the input drive shaft (1) by means of a fifth shift element (E) is made connectable with the carrier (45) of the planet gears (42) of the fourth planetary gear set (RS4), in that the carrier (45) of the fourth planetary gear set (RS4) is connected to the internal gear (33) of the third planetary gear set (RS3) and by means of a fourth shift element (D) is made immobile, in that the sun gear (41) of the fourth planetary gear set (RS4) by means of a sixth shift element (F) is made immobile and in that the carrier (43) of the fourth planetary gear set (RS4) is connected with the carrier (35) of the planet gears (32) of the third planetary gear set (RS3) as well as with the output drive shaft (2), (See FIG. 8A).

12. The multi-step transmission according to claim 1, wherein the input drive shaft (1) is connected with the sun gear (21) of the second planetary gear set (RS2), in that the outer planet gears (22″) of the second planetary gear set (RS2) are coupled with the planet gears (12) of the first planetary gear set (RS1), in that the sun gear (11) of the first planetary gear set (RS1) is made immobile, in that the input drive shaft (1), by means of a second shifting element (B) can be connected with the sun gear (41) of the fourth planetary gear set (RS4) and by means of a fifth shifting element (E) can be connected with the carrier (45) of the planet gears (42) of the fourth planetary gear set (RS4), which is connected with the internal gear (33) of the third planetary gear set (RS3), in that the common carrier (15) of the outer planet gears (22″) of the second planetary gear set (RS2) and the planet gears (12) of the first planetary gear set (RS1) is connected with the carrier (25′) of the inner planet gears (22′) of the second planetary gear set (RS2) and by means of a sixth shift element (F) can be connected with the sun gear (41) of the fourth planetary gear set (RS4), in that the internal gear (13) of the first planetary gear set (RS1) is connected with the internal gear (23) of the second planetary gear set (RS2) and by means of a fourth shift element (D) can be connected with the carrier (45) of the fourth planetary gear set (RS4) and by means of a third shift element (C) can be connected with the sun gear (41) of the fourth planetary gear set (RS4), in that the common carrier (15) for outer planet gears (22′) of the second planetary gear set (RS2) and the planet gears (12) of the first planetary gear set (RS1) by means of a first shift element (A) can be connected with the sun gear (31) of the third planetary gear set (RS3), and in that the internal gear (43) of the fourth planetary gears (RS4) is connected to the carrier (35) of the sun gear (32) of the third planetary gear set (RS3) and to the output drive shaft (2), (See FIG. 15A).

13. The multi-step transmission according to claim 1, wherein the input-side gear set (VS) is comprised of a non-shiftable planetary gear set (RS1), which produces on its output-side, a speed of rotation (n1), which, besides the input speed of rotation (n) of the input drive shaft, optionally can be shifted in such a manner to at least one of the two shiftable planetary gear sets (RS3, RS4) which act upon the output gear sets (NS) by means of selective closure of the shift elements (A to F), that, for the shift change from one gear into the following respective higher or lower gear of the two immediately activated shifting elements in respect to which only one shift element is open and one shift element is closed, whereby at least seven forward gears are formed and the number of the forward gears is at least greater by two than the number of the shift elements.

14. The multi-step transmission according to claim 13, wherein the sun gear (11) of the input-side planetary gear set (RS1) is connected with the input drive shaft (1), in that the carrier (15′) of the inner planet gears (12′) of the input-side planetary gear set (RS1) is made immobile and is connected to the carrier (15″) of the outer planet gears (12″) of the input-side planetary gear set (RS1), in that the input drive shaft (1), by means of a fifth shift element (E) is connectable with the carrier (45) of the second output-side planetary gear set (RS4), whereby the carrier (45) of the second output-side planetary gear set (RS4) is connected with the carrier (35′) of the inner planet gears (32′) of the second output-side planetary gear set (RS3) and with the carrier (35″) of the outer planet gears (32″) of the second output-side planetary gear set (RS3) and by means of a fourth shift element (D) can be immobilized, in that the input drive shaft (1), by means of a second shift element (B) can be connected with the sun gear (41) of the second output-side planetary gear set (RS4), in that the inner planet gears (12′) and the carrier (15″) of the outer planet gears (12″) of the input-side planetary gear set (RS1), by means of a third shift element (C) are connectable with the sun gear (41) of the second output-side planetary gear set (RS4), in that the internal gear (13) of the input-side planetary gear set (RS1), by means of a sixth shift element (F) is connectable with the sun gear (41) of the second output-side planetary gear set (RS4) and by means of a first shift element (A) is connectable with the sun gear (31) of the of the first output-side planetary gear set (RS3), in that the internal gear (43) of the second output-side planetary gear set (RS4) is connected with the internal gear (33) of the first output-side planetary gear set (RS3) and with output drive shaft (2), and in that the outer planet gears (32″) of the first output-side planetary gear set (RS3) and the planet gears (42) of the second output-side planetary gear set (RS4) are coupled together, (See FIG. 9A).

15. The multi-step transmission according to claim 13, wherein the sun gear (11) of the input-side planetary gear set (RS1) is connected with input drive shaft (1), in that the internal gear (13) of the input-side planetary gear set (RS1) is made immobile, in that the input drive shaft (1), by means of a first shift element (A) can be connected with the sun gear (31) of the first output-side planetary gear set (RS3) and by means of a fifth shift element (E) can be connected with the carrier (45) of the planet gears (42) of the second output-side planetary gear set (RS4), in that the carrier (45) of the second output-side planetary gear set (RS4) is connected with internal gear (33) of the first output-side planetary gear set (RS3), in that the carrier (45) of the second output-side planetary gear set (RS4) and the internal gear (33) of the first output-side planetary gear set (RS3), by means of a fourth shift element (D) can be connected with the carrier (15) of the planet gears (12) of the input-side planetary gear set (RS1), in that the sun gear (41) of the second output-side planetary gear set (RS4), by means of a third shift element (C) can be made immobile, in that the carrier (15) of the planet gears (12) of the input-side planetary gear set (RS1) by means of a second shift element (B) is connectable with the sun gear (41) of the second output-side planetary gear set (RS4) and in that the internal gear (43) of the second output-side planetary gear set (RS4) is connected with the carrier (35) of the planet gears (32) of the first planetary gear set (RS3) and with the output drive shaft (2), (See FIG. 12A).

16. The multi-step transmission according to claim 13, wherein the sun gear (11) of the input-side planetary gear set (RS1) is connected with the input drive shaft (1), in that the carrier (15′) of the inner planet gears (12′) and the carrier (15″) of the outer planet gears (12″)of the input-side planetary gear set (RS1) are connected with one another and made immobile, in that the carrier (35′) of the inner planet gears (32′) of the first output-side planetary gear set (RS3) is connected with the carrier (35″) of the outer planet gears (32″) of the first output-side planetary gear set (RS3) and is connected with the carrier (45) of the planet gears (42) of the second output-side planetary gear set (RS4), in that the connected carriers (35′, 35″, 45) of the first and second output-side planetary gear sets (RS3, RS4), by means of a fourth shift element (D) are connectable with the internal gear (13) of the input-side planetary gear set (RS1), in that the input drive shaft (1), by means of a first shift element (A) is connectable with the sun gear (31) of the first output-side planetary gear set (RS3), in that the input drive connected carrier ( 35″, 35′, 45) of the first and second output-side planetary gear set (RS3, RS4), in that the sun gear (41) of the second output-side planetary gear set (RS4), by means of a third shift element (C) can be made immobile, in that the internal gear (13) of the input-side planetary gear set, by means of second shift element (B) is connectable with the sun gear (41) of the second output-side planetary gear set (RS4) and in that the internal gear (33) of the first output-side planetary gear set (RS) and the first output-side planetary gear set (RS3) and the internal gear (43) coupled thereto of the second output-side planetary gear set (RS4) are connected with the output drive shaft (2), (See FIG. 13A).

17. The multi-step transmission according to claim 13, wherein the internal gear (13) of the input-side planetary gear set (RS1) is connected with the input drive shaft (1), in that the sun gear (11) of the input-side planetary gear set (RS1) is made immobile, in that the input drive shaft (1) by means of a fifth shift element (E) is connectable with the carrier (45) of the planet gears (42) of the second output-side planetary gear set (RS4), whereby the carrier (45) is connected with the sun gear (31) of the first output-side planetary gear set (RS3) and by means of a first shift element (A) is connectable with the internal gear (33) of the first output-side planetary gear set (RS3), whereby the internal gears (33, 43) of the first and second output-side planetary gear sets (RS3, RS4) are connected to one another and whereby the carrier (15) of the input-side planetary gear set (RS1), by means of a second shift element (B) is connectable with the sun gear (41) of the second output-side planetary gear set (RS4) and by means of a fourth shift element (D) is connectable with the carrier (35) of the planet gears (32) of the first output-side planetary gear set (RS3) is connected with the output drive shaft (2), (See FIG. 14A).

18. The multi-step transmission according to claim 1, wherein the input-side gear set (VS) is comprised of three non-shiftable, coupled planetary gear sets (RS1, RS2a, RS2b), whereby the three said planetary gear sets (RS1, RS2a, RS2b) produce as output three speeds of rotation (n1, n2, n2b) besides the input speed of rotation (n) of the input drive shaft (1). These are optionally shiftable by selective closure of the shift elements (A to G) into at least one of the two shiftable planetary gear sets (RS3, RS4) of the output-side gear set (NS) which act on the output drive shaft (2) in such a manner, that for shifting from one gear into the next following higher or lower gear of the two just activated shift elements, respectively, in each case only one shift element closes and an additional shift element opens and in that at least seven forward gears are formed.

19. The multi-step transmission according to claim 18, wherein the number of the forward gears is at least greater by 2 than the number of the shift elements (A to G).

20. The multi-step transmission according to claim 18, wherein as an input-side gear set (VS), a first input-side planetary gear set (RS1), a second input-side planetary gear set (RS2a) and a third input-side planetary gear set (RS2b) are provided, which forms a non-shiftable, three-carrier, five-shaft gear train, wherein at least one shaft runs with the input speed of rotation (n) of the input drive shaft (1) and at least one further shaft is stationary, and in that the output-side gear set (NS) is a shiftable two-carrier, four-shaft gear set, which encompasses a first output-side planetary gear set (RS3) and a second output-side planetary gear set (RS4).

21. The multi-step transmission according to claim 18, wherein the first input-side planetary gear set (RS1) is connected with the input drive shaft (11), in that the outer planet gears (22b″) of the third input-side planetary gear set (RS2b) and the planetary gears (22a) of the second input-side planetary gear set (22a) of the second input-side planetary gear side (RS2a) are coupled with one another, in that the common carrier (25b″) of the planet gears (22a) of the second input-side planetary gear set (RS2a) and the outer planet gears (22b″) of the third input-side planetary gear set (RS2b) is connected with the carrier (25b′) of the inner planet gears (22b′) of the third input-side planetary gear set (RS2b) and with the carrier (15) of the planetary gears (12) of the first input-side planetary gear set (RS1), in that the internal gear (13) of the first input-side planetary gear set (RS1) and the sun gear (21b) of the third input-side planetary gear set (RS2b) are made immobile, in that the internal gear (23a) of the second input-side planetary gear set (RS2a) and the internal gear (23b) of the third input-side planetary gear set (RS2b) by means of a fourth shift element (D) are made connectable with the carrier (45) of the planet gears (42) of the second output-side planetary gear set (RS4), in that the carrier (45) of the second output-side planetary gear set (RS4) is connected with the internal gear (33) of the first output-side planetary gear set (RS3), in that the internal gear (23a) of the second input-side planetary gear set (RS2) and the internal gear (23b) of the third input-side planetary gear set (RS2b), by means of a sixth shift element (F) is connectable with the internal gear (43) of the second output-side planetary gear set (RS4), in that the input drive shaft (1), by means of a first shift element (A) can be connected with the sun gear (41) of the second output-side planetary gear set (RS4) and with the therewith connected sun gear (31) of the first output-side planetary gear set (RS3), and by means of a fifth shift element (E) can be connected with the carrier (45) of the second output-side planetary gear set (RS4), in that the internal gear (43) of the second output-side planetary gear set (RS4), by means of a third shift element (C) is made immobile, the sun gear (21a) of the second input-side radial gear set (RS2), by means of a second shift element (B) is connectable with the internal gear (43) of the second output-side planetary gear set (RS4), which the common carrier (25b″) of the planet gears (22a) of the second input-side planetary gear set (RS2a) and the outer planet gears (22b″) of the third input-side planetary gear set (RS2b) by means of a seventh shift element (G) is connectable with the internal gear (43) of the second output-side planetary gear set (RS4) and the carrier (35) of the planet gears (32) of the first output-side planetary gear set (RS3) is connected with the output drive shaft (2), (See FIG. 10A).

22. The multi-step transmission according to claim 1, wherein the input gear set (VS) is comprised of at least four, non-shiftable, coupled planetary gear sets (RS1a, RS1b, RS2a, RS2b), which, deliver on their output-side four speeds of rotation (n1a, n1b, n2a, n2b), which, besides the input rotary speed (n) of the input drive (1), optionally, on at least one of the two shiftable output-side planetary gear sets (RS3, RS4) which act on the output drive shaft (2) of the output gear set (NS), by means of selective closure of the shift elements (A to H) are shiftable in such a manner, that for a shift change from one gear into the next contiguous higher or lower gear of the two just activated shift elements, respectively, only one shift element is closed and another shift element is open, and that at least seven forward gears are formed.

23. The multi-step transmission according to claim 22, wherein the number of the forward gears is at least about two greater that is the number of the shift elements (A to H).

24. The multi-step transmission according to claim 22, wherein as an input-side gear set (VS) a first input-side planetary gear set (RS1a), a second input-side planetary gear set (RS1b), a third input-side planetary gear set (RS2a) and a fourth input-side planetary gear set (RS2b) are provided, which form a non-shiftable gear drive which possesses four carriers and six shafts, wherein at least one shaft with the input speed of rotation (n) of the input drive shaft (1) runs, and at least one of the additional shafts is made immobile, and in that the shiftable output gear set (NS) is a shiftable two-carrier, four shaft drive, which encompasses a first output-side planetary gear set (RS3) and a second output-side planetary gear set (RS4).

25. The multi-step transmission according to claim 22, wherein the planet gears (12a) of the first input-side planetary gear set (RS1a) are coupled with the outer planet gears (12b″) of the second input-side planetary gear set (RS1b), whereby the common carrier (15b″) of the planet gears (12a) of the first input-side planetary gear set RS1a and the outer planet gears (12b″) of the second input-side planetary gear set (RS1b) is connected with the carrier (15b′) of the inner planet gears (12b′) of the second input-side planetary gear (RS1b), in that the planet gears 22a of the third input-side planetary gear set (RS2a) are coupled with the outer planet gears (22b″) of the fourth input-side planetary gear set (RS2b), whereby the common carrier (25b″) of the planet gears (22a) of the third input-side planetary gear set (RS2a) and the outer planet gears (22b″) of the fourth input-side planetary gear set (RS2b) is connected with the carrier (25b′) of the inner planet gears (22b′) of the fourth input-side planetary gear set (RS2b) and is also connected to the common carrier (15b″) for the planet gears (12a) of the first input-side planetary gear set (RS1a) and the outer planet gears (12b″) of the second input-side planetary gear set (RS1b), in that the input drive shaft (1) is connected with the sun gear (11b) of the second input-side planetary gear set (RS1b) and with the sun gear (21a) of the third input-side planetary gear set (RS2a), in that the sun gear (11a) of the first input-side planetary gear set (RS1a) is made immobile, in that the internal gear (13a) of the first input-side planetary gear set (RS1a) is connected with the internal gear (13b) of the second input-side planetary gear set (RS1b) and by means of a second shift element (B) can be connected with the sun gear (41) of the second output-side planetary gear set (RS4), in that the input drive shaft (1) by means of a first shift element (A) is connectable with sun gear (31) of the first output-side planetary gear set (RS3) and by means of a fifth shift element (E) can be connected with the internal gear (33) of the first output-side planetary gear set (RS3), which is connected with the carrier (45) of the planet gears (42) of the second output-side planetary gear set (RS4), in that the sun gear (21b) of the fourth input-side planetary gear set (RS2b), by means of a first shift element (D) is connectable with the internal gear (33) of the first output-side planetary gear set (RS3) and with the carrier (45) of the second output-side planetary gear set (RS4) and by means of a sixth shift element (F) is connectable with the sun gear (41) of the second output-side planetary gear set (RS4), in that the carrier (25″) of the outer planet gears (22″) of the fourth input-side planetary gear set (RS2b), by means of an eighth shifting element (H) is connectable with the sun gear (41) of the second output-side planetary gear set (RS4), in that the internal gear (23a) of the third input-side planetary gear set (RS2b) is connected with the internal gear (23b) of the fourth input-side planetary gear set (RS2b) and by means of a seventh shift element (G) is connectable with the sun gear (41) of the second output-side planetary gear set (RS4), in that the sun gear (41) of the second output-side planetary gear set (RS4), by means of a third shift element (C) can be immobilized and in that the carrier (35) of the planet gears (32) of the first output-side planetary gear set (RS3) is connected with the internal gear (43) of the second output-side planetary gear set (RS4) and is also connected with the output drive shaft (2), (See FIG. 11A).

26. The multi-step transmission according to claim 22, wherein the input drive shaft (1) is connected with the sun gear (11a) of the first input-side planetary gear set (RS1a) in that the outer planet gears (12a″) of the first input-side planetary gear set (RS1a), the planet gears (12b) of the second input-side planetary gear set (RS1b), the planet gears (22a) of the third input-side planetary gear set (RS2a) and the planet gears (22b) of the fourth input-side planetary gear set (RS2a) are constructed as a stepped planet gear, in that the carrier (15a′) of the inner planet gears (12a′) of the first input-side planetary gear set (RS1a) is connected with the carrier (15a″) of the outer planet gears (12a″) of the first input-side planetary gear set (RS1a), with the carrier (15b) of the planet gears (12b) of the second input-side planetary gear set (RS1b), with the carrier (25a) of the planet gears (22a) of the third input-side planetary gear set (RS2a) and with the carrier (25b) of the planet gears (22b) of the fourth input-side planetary gear set (RS2b), and by means of a seventh shift element (G) is connectable with the sun gear (41) of the second output-side planetary gear set (RS4), in that the sun gear. (11b) of the second input-side planetary gear set (RS1B) is made immobile, in that the sun gear (41) of the second output-side planetary gear set (RS4) by means of a third shift element be made immobile, in that the internal gear (23a) of the third input-side planetary gear set (RS2a) by means of an eighth shift element (H) is connectable with the sun gear (41) of the second output-side planetary gear set (RS4), in that the input drive shaft (1) by means of a first shift element (A) is connectable with the sun gear (31) of the first output-side planetary gear set (RS3), in that the internal gear (13a) of the first input-side planetary gear set (RS1a) and the internal gear (13b) of the second input gear side planetary gear set RS1b) are connected with one another and by means of a second shift element (B) are connectable with the sun gear (41) of the second output-side planetary gear set (RS4), in that the connected carriers (15a″, 15a′) of the outer and inner planet gears (12a″, 12a′) of the first input-side planetary gear set, by means of a fourth shift element D are connectable with the carrier (35′) of the inner planet gears (32′) of the first output-side planetary gear set (RS3), in that the outer planet gears (32″) of the first output-side planetary gears (RS3) and the planet gears (42) of the second output planetary gear set (RS4) are coupled together, in that the carrier (35″) of the outer planet gears (32″) of the first output-side planetary gear set (RS3) is connected with the carrier (35′) of the inner planet gears (32′) of the first output-side planetary gear set (RS3) and the carrier (45) of the planet gears (42) of the second output-side planetary gear set (RS4), and by means of a fifth shift element (E) is connectable with the input drive shaft (1), in that the sun gear (21b) of the fourth input-side planetary gear set (RS2b), by means of a sixth shift element (F) is connectable with the sun gear (41) of the second output-side planetary gear (RS4) and in that the internal gear (33) of the first output-side planetary gear set (RS3) and the internal gear (43) of the second output-side planetary gear set (RS4) are connected in common with the output drive shaft (2), (See FIG. 16A).

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**Patent History**

**Patent number**: RE43315

**Type:**Grant

**Filed**: Oct 11, 2000

**Date of Patent**: Apr 17, 2012

**Assignee**: ZF Friedrichshafen AG (Friedrichshafen)

**Inventor**: Peter Ziemer (Tettnang)

**Primary Examiner**: Sherry Estremsky

**Attorney**: Davis & Bujold, P.L.L.C.

**Application Number**: 11/529,692

**Classifications**

**Current U.S. Class**:

**Transmission Includes Three Relatively Rotatable Sun Gears (475/275)**

**International Classification**: F16H 3/62 (20060101);