Abstract: In an automatic transmission (AT) in which an input shaft (Input) and an output gear (Output) are disposed on the same axis and three clutches (C1-C3) and two brakes (B1, B2) are selectively operated to provide six forward speeds, first and second planetary gear sets (GS1, GS2) are configured to consistently reduce the speed of input rotation and output the speed-reduced rotation, thereby enabling downsizing of them. The first and second planetary gear sets (GS1, GS2) are arranged in a transmission case at both the axial ends thereof. Third and fourth planetary gear sets (GS3, GS4) are connected to each other to have four rotation elements in combination, thereby constituting a Simpson planetary gear train. One of the four rotation elements (a fourth carrier (PC4) in an illustrated example) is connected to the output gear (Output).

Abstract: An automatic transmission comprises first, second and third gear sets 10, 20, 30 each formed as a single-pinion type planetary gear set, first and second clutches 40, 50, and first, second and third brakes 60, 70, 80. A first sun gear 11, a first ring gear 14, a second ring gear 24, a third sun gear 31 and a first carrier 13 are continuously interconnected with a second sun gear 21, a second carrier 23, a third carrier 33, an input shaft 4 and an output gear 7, respectively. The first clutch 40 is operable to selectively connect and disconnect the first sun gear 11 and the second sun gear 21 to/from the input shaft 4, and the second clutch 50 is operable to selectively connect and disconnect the first ring gear 14 and the second carrier 13 to/from the input shaft 4. The first brake 60 is operable to selectively connect and disconnect the first ring gear 14 and the second carrier 23 to/from a casing 6.

Abstract: On an input shaft are provided in order from a side of an engine a torque converter with a lock-up clutch, a first planetary gear set as a multiplying mechanism, a counter drive gear outputting a rotational drive force to a countershaft, a second planetary gear set as a speed-change element, a third planetary gear set as a speed-change element. Accordingly, there can be provided an automatic transmission for six forward speeds with plural planetary gear sets, clutches and brakes that can properly reduce a clutch capacity and restrain gear noises with its compact and light-weighted structure.

Abstract: There are provided a first planetary gear set including a first sun gear, a first carrier, and a first ring gear; a second planetary gear set including a second sun gear, a second carrier, and a second ring gear; and a third planetary gear set including a third sun gear, a third carrier, and a third ring gear. A first forward speed ratio is established with the engagement of a third brake and a first clutch; a second forward speed ratio is established with the engagement of a first brake and the first clutch; a third forward speed ratio is established with the engagement of a second brake and the first clutch; a fourth forward speed ratio is established with the engagement of the first clutch and a second clutch; a fifth forward speed ratio is established with the engagement of the second brake and the second clutch; and a sixth forward speed ratio is established with the engagement of the first brake and the second clutch.

Abstract: A burn-in test signal path is provided in parallel with an ordinary signal path with respect to an analog circuit. A signal waveform converting circuit for converting a burn-in test signal of a digital waveform into a burn-in test signal of an analog waveform is provided in the burn-in test signal path. The ordinary signal path is controlled to switch over to the burn-in test signal path in the burn-in test of the analog circuit.

Abstract: A transmission apparatus is disclosed which can improve the locking response speed of a lockup clutch when an engine is driven by the output side, without largely changing the structure of the lockup clutch or the like. In the lockup clutch of this transmission apparatus, fixing portions (21a) for a support member (24) of a damper spring (23) are fixed to a plurality of portions on a predetermined circumference of a piston (21) which are inside a friction member (22). Projections (21b) extending in the radial direction are formed, at those positions of the lockup piston (21) which are inside the friction member (22) and sandwiched by the fixing portions (21a) for the support member (24) of the damper spring (23), to project toward a front cover.

Abstract: There is provided an automatic transmission comprising a first shaft capable of receiving torque from an engine, and four planetary gear sets arranged coaxially on the first shaft and in series in an axial direction of the first shaft. Each of the four planetary gear sets has a single sun gear and a single ring gear. Further, the automatic transmission comprises an output wheel arranged coaxially on the first shaft, and capable of outputting torque transmitted from the engine through some of the four planetary gear sets. The output wheel is arranged between two of the four planetary gear sets. Accordingly, the noise or vibration from the planetary gear sets in the automatic transmission may be reduced, while the overall length of the first shaft may be made shorter, and the overall size of the automatic transmission may be made smaller.

Abstract: In an automatic transmission (AT) in which an input shaft (Input) and an output gear (Output) are disposed on the same axis and three clutches (C1-C3) and two brakes (B1, B2) are selectively operated to provide six forward speeds, first and second planetary gear sets (GS1, GS2) are configured to consistently reduce the speed of input rotation and output the speed-reduced rotation, thereby enabling downsizing of them. The first and second planetary gear sets (GS1, GS2) are arranged in a transmission case at both the axial ends thereof. Third and fourth planetary gear sets (GS3, GS4) are connected to each other to have four rotation elements in combination, thereby constituting a Simpson planetary gear train. One of the four rotation elements (a fourth carrier (PC4) in an illustrated example) is connected to the output gear (Output).

Abstract: A transmission apparatus is disclosed which can improve the locking response speed of a lockup clutch when an engine is driven by the output side, without largely changing the structure of the lockup clutch or the like. In the lockup clutch of this transmission apparatus, fixing portions (21a) for a support member (24) of a damper spring (23) are fixed to a plurality of portions on a predetermined circumference of a piston (21) which are inside a friction member (22). Projections (21b) extending in the radial direction are formed, at those positions of the lockup piston (21) which are inside the friction member (22) and sandwiched by the fixing portions (21a) for the support member (24) of the damper spring (23), to project toward a front cover.

Abstract: An automatic transmission control system provided with a speed sensor for monitoring an input speed to the automatic transmission, on one hand, prohibits gear shifts only to gears which are provided by alternately locking and unlocking two friction coupling elements at a timing determined essentially based on an input speed when an failure of the speed sensor occurs and, on the other hand, permits gear shifts to gears which are provided in participation of the one-way clutch by alternately locking and unlocking the two friction coupling elements, a timely alternate lock and unlock operation of the two friction coupling elements being spontaneously caused by the unlock operation of one of the two friction coupling elements and gear shifts to gears which are provided by locking one of the two friction coupling elements and unlocking the other with common pressure or unlocking one of the two friction coupling elements and locking the other with common pressure.

Abstract: An apparatus for controlling an automatic transmission is disclosed. A 2nd speed is established in which hydraulic pressure is supplied only into an engaging chamber of a 2-4 brake by a first duty solenoid valve so that the brake is applied. A 3rd speed is established in which the hydraulic pressure is supplied into a releasing chamber of the brake and a hydraulic chamber of a 3-4 clutch by a second duty solenoid valve under the condition of the hydraulic pressure being supplied into the engaging chamber of the brake so that the brake is released and the 3-4 clutch is engaged. When the 2nd speed is changed to the 3rd speed, a controller increases the hydraulic pressure supplied into the releasing chamber of the brake and the hydraulic chamber of the 3-4 clutch in a case where a failure, in which the first solenoid valve is fixed under a condition that the first solenoid valve supplies the hydraulic pressure into the engaging chamber, is detected.

Abstract: An automatic transmission control system for an automotive automatic transmission including a speed sensor for detecting a vehicle speed of the vehicle, a load sensor for detecting a load acting on the driving torque generator, a torque sensor for detecting input torque transmitted to the automatic transmission from the driving torque generator, first working fluid pressure control communicating both a first friction coupling element's unlocking pressure chamber and a second friction coupling element's pressure chamber with the working fluid source in the hydraulic pressure control system for controlling supply of working fluid pressure to and from both the unlocking pressure chambers and a second working fluid pressure control in the fluid path communicating both the first friction coupling element's locking pressure chamber with the working fluid source for controlling supply of working fluid pressure to and from the first friction coupling element's locking pressure chamber.

Abstract: An automatic transmission control system for an automatic transmission including a hydraulic pressure control circuit which supplies locking and unlocking pressures selectively to a plurality of friction coupling elements to lock and unlock the selected friction coupling elements, changing a torque transmission path in a transmission gear mechanism to provide available gears, a specific one of which is achieved by locking and unlocking simultaneously specific friction coupling elements.

Abstract: A torque responsive hydraulic control system for an automatic transmission with a plurality of hydraulically actuated friction control elements. A working hydraulic pressure in the elements is controlled during shifting such that a pressure in a first element is removed after a specific state of the element is achieved. The removal being responsive to the torque of an input shaft of the transmission, the expiration of a specific time period, or a position of the throttle valve of a driving engine.

Abstract: An automatic transmission control system, which includes a 2-4 brake having a servo apply fluid chamber and a servo release fluid chamber and a 3-4 clutch having a fluid chamber and causes a 3-2 shift by engaging the 2-4 brake and disengaging the 3-4 clutch, controls engaging pressure for the 3-4 clutch by way of controlling servo apply pressure for the 2-4 brake to disengage the 3-4 brake so as thereby to increase turbine speed during the 3-2 gear shift and, at near the end of the 3-2 gear shift, brings the 2-4 brake into engagement. During control of disengagement of the 3-4 clutch, the pressure difference between servo apply pressure and servo release pressure is changed to become greater at the beginning of the gear shift.

Abstract: A control system of an automatic transmission includes a torque converter, a lock-up clutch for directly connecting input and output members of the torque converter, a pressure control valve which changes a hydraulic pressure to control an engaging force of the lock-up clutch, and a pressure regulator, disposed in an engaging passage, which supplies hydraulic pressure to engage a frictional element. The pressure regulator adjusts a primary pressure and produces an output hydraulic pressure corresponding to a control pressure introduced into a control port of the pressure regulator. A control pressure supply device is provided for introducing the control pressure, controlled by the pressure control valve, into the control port of the pressure regulator. The number of parts can be reduced without producing any inconvenience.

Abstract: An automatic transmission control system including a hydraulic pressure control circuit which supplied locking and unlocking pressure to selectively lock and unlock the selected friction coupling elements so as to change a torque transmission path in the transmission gear mechanism and thereby to provide desired gears, a specific one of which is achieved by locking and unlocking simultaneously specific friction coupling elements.

Abstract: A control system for an automatic transmission having at least a friction coupling element which is coupled with a hydraulic pressure increasing by way of a leveled transitional pressure has an accumulator which discharge a high level of pressure accumulated therein into the friction coupling element during a gear shift under the condition where the line pressure is low.

Abstract: A control system for an automatic transmission having friction coupling elements, at least one of which is locked in 3rd and 4th gears and unlocked in 1st and 2nd gears, includes a first shift valve shiftable between 3rd and 4th gears, and second shift valve shiftable between in 2nd gear and 1st gear in which engine brake available, and a solenoid valve providing control pressure which is selectively directed to these shift valves and cause them to shift so as to lock or unlock the friction coupling elements.

Abstract: A control system for an automatic transmission having a transmission gear mechanism and a plurality of friction coupling elements which are selectively locked and unlocked with hydraulic oil to change power transmission paths to place the automatic transmission into desired available gears, a first one of the friction coupling elements having a locking pressure chamber and an unlocking pressure chamber and being locked when operating oil is supplied into only the locking pressure chamber and unlocking when operating oil is coincidentally supplied into the locking pressure chamber and the unlocking pressure chamber, and a second one of the friction coupling elements having a locking/unlocking pressure chamber in communication, with the unlocking pressure chamber of the first friction coupling element and being locked only when operation oil is supplied into the locking/unlocking pressure chamber.