HONING MACHINE AND METHOD FOR CARRYING OUT HONING OPERATIONS ON ORTHOGONALLY ALIGED BORES IN A WORKPIECE

Abstract

The invention relates to a honing machine and to a method for carrying out honing operations on orthogonally aligned bores in a workpiece, in particular for honing cylinder bores and a bearing race bore in a cylinder crankcase.

Description

BACKGROUND

The invention concerns a honing machine and method for carrying out honing operations on orthogonally aligned bores in a workpiece, in particular for honing of cylinder bores and a bearing race bore in a cylinder crankcase, with the characteristics of the preamble of claim 1, a honing machine with the characteristics of the preamble of claim 2, a honing machine with the characteristics of the preamble of claim 4, and a method for carrying out honing operations on orthogonally aligned bores in a workpiece, in particular for honing of cylinder bores and a bearing race bore in a cylinder crankcase, with the characteristics of the preamble of claim 8, a method with the characteristics of the preamble of claim 9, a method with the characteristics of the preamble of claim 10, and a method with the characteristics of the preamble of claim 11.

The cylinder crankcase, often referred to as a “crankcase” or “engine block”, is an integral component of combustion engines or internal-combustion engines, as they, for example, are used in personal or freight vehicles, aircraft, ships, and stationary facilities. The most common variant is the multi-cylinder engine, the pistons of which are connected to the rotating crank shaft via con rods, and which convey the force generated by the engine to the wheels, ship propellers, aircraft propellers, generators, or similar.

The cylinder crankcase is one example of a workpiece with orthogonally aligned bores.

Within the engine block are multiple cylinder bores in a straight alignment. The crank shaft in straight or V-engines is below, in a boxer engine it is between the cylinders and rests against the cylinder crankcase in the bearings of the crank shaft bearing bore. The bearings are usually slider bearings, sometimes roller bearings. In order to ensure high concentricity of the crank shaft and thus minimize unwanted signs of wear and vibrations during operation, the crank shaft must meet strict form tolerance requirements. The bearings must also be highly tolerated with regard to their size and position in the cylinder crankcase.

The relatively strict tolerances of the pertinent parts of a combustion engine and a cylinder crankcase stem from the complex functions of these parts. The shape, dimensions and surface topography of the cylinder bore largely determine the wear, friction, oil use, and emission values of the combustion engine as well as the performance and effectiveness based on the friction. The compressed combustion chamber volume mainly affects the compression of the engine. This in turn affects the performance and, due to the course of combustion, the emission values and engine sounds.

The exact position of the crank shaft relative to the pistons or cylinder bores is, among other things, important for reducing wear in highly strained engine parts. In particular, these are pistons/piston bolts, con rods, and con rod bearings on the crank shaft, as well as the bearing of the crank shaft in the cylinder crankcase. For the position of the bore axis not only the absolute position in the space, but also the angle position or orientation plays a role. For example, in control gears with a coupling, the crank shaft and entry shaft of the gear move together. This means that precise coaxiality of the two shafts is crucial for a long service life.

SUMMARY OF THE INVENTION

The task of this invention lies in the provision of a honing machine and a method for carrying out honing operations on orthogonally aligned bores in a workpiece, as with the cylinder crankcase described above, wherein the bores in a workpiece can be processed with high precision, in a short time, with a secure method, completely by means of honing.

This task is achieved with a honing machine for carrying out honing operations on orthogonally aligned bores in a workpiece, wherein the honing machine comprises:

A machine base and a machine-internal transport system arranged on the machine base.

The transport system comprises a rotary table that rotates around a vertical rotary table axis. The rotary table comprises multiple workpiece intakes. The workpiece intakes are arranged offset from one another in the circumferential direction at a radial distance from the rotary table axis such that a workpiece inserted into a workpiece intake can be successively moved along a circular path and through various workstations of the honing machine via rotation of the rotary table. In other words, the rotary table moves workpieces along a circular path from one workstation to another. The transport system facilitates the quick passage of the workpieces between the various workstations. The rotary table can be designed as an elevating rotary table. The rotary table or slab thereof can be round or have a different geometric shape, e.g., triangular or rectangular.

The machine-internal transport system, and in particular the rotary table, make it possible, for example, to load and unload the workpiece intake with one single loading station. Unlike transport machines, it is possible for the workpieces to exit the honing machine at the same location where they entered. This simplifies the loading and unloading, and in particular the coupling of the honing machine to an external conveyor system. An external conveyor system can be used, if necessary, with other honing machines and/or with other processing machines to create a production line.

To this end, at least one of the workstations is a vertical honing station comprising at least one vertical honing unit. The vertical honing unit comprises having a honing spindle with a honing tool, wherein the spindle axis is aligned parallel to the rotary table axis. The honing of a vertically aligned bore is performed via a relative motion rotating around a spindle axis and translatory along the spindle axis, between the workpiece and the honing spindle or honing tool. This relative motion is usually oscillating. The spindle is typically rotated in the bore and moved back and forth along the bore axis.

Another workstation is a horizontal honing station comprising at least one horizontal honing unit. The horizontal honing unit comprises a honing spindle with a honing tool. The honing of a horizontally aligned bore is performed via a relative motion rotating around a horizontal spindle axis and translatory along the horizontal spindle axis, between the workpiece and honing spindle or honing tool. This relative motion is usually oscillating. The spindle is typically rotated in the bore and moved back and forth along the bore axis. However, when honing the horizontally aligned bore, it may be configured that the honing tool is rotated and only translatory moved into and out of the bore one time. Typically, honing retainers of the tool are set to an oversize, meaning that they have a processing diameter that is slightly greater than the diameter of the bore being processed.

The honing machine further comprises an actuator unit. This is designed and arranged such that the actuator unit moves the workpiece in order to carry out the honing in the horizontal honing station.

The honing spindle of the horizontal honing unit can be arranged immovably in the honing machine, in particular during the honing. But it is also possible, that during the honing, in addition to the movement of the workpiece, the honing spindle of the horizontal honing unit also moves, in particular in inverted direction, to participate in the aforementioned relative motion between the workpiece and honing spindle.

The motion of the workpiece via the actuator unit can reduce the motion of the horizontal honing unit or, if the horizontal honing unit is immobile, only be limited to the rotation of the honing spindle. This increases the precision with which the honing spindle or honing tool can be used during the honing. This results in a more precise overall result of the honing operation.

Furthermore, the task at hand is also achieved with a honing machine with the characteristics of the preamble of claim 1, in particular with the characteristics of claim 1, wherein the machine-internal transport system is designed such that the workpiece is moved from the rotary table to carry out the honing in the horizontal honing station. The honing is carried out outside of the rotary table. The workpiece is transported in particular outside of the circular path where the rotary table moves the workpieces. It is possible for the workpiece to be rotated and aligned outside of the rotary table. A device for moving the workpiece from the rotary table, and that also returns the workpiece to the rotary table, is typically provided. During the movement of the rotary table, the workpiece does not leave the honing machine. The processing is typically carried out outside of the rotary table, but on the same machine base where the rotary table is also located.

Because the honing takes place outside of the rotary table, there is no transfer of unwanted vibrations and oscillations to the rotary table caused by the honing, or they are minimized. Other workpieces on the rotary table are thus also unaffected by these vibrations or oscillations. This increases the precision during the processing of the workpieces at the other workstations.

Furthermore, the task at hand is achieved with a honing machine with the characteristics of the preamble of claim 1, in particular with the characteristics of claim 1 or 2, wherein the horizontal spindle axis extends along a processing direction. The translatory relative motion during the honing occurs along an axis specified by the processing direction. The processing direction is parallel to a direction extending radially through the rotary table axis, yet is spaced from the rotary table axis. In other words, the processing direction runs along a straight line that does not pass through the center of the rotary table.

This means the horizontal honing unit can be more flexibly positioned and aligned on the honing machine. For example, multiple, in particular two horizontal honing units can be placed next to each other and/or parallel to each other on the honing machine. This results in acceleration of the entire process.

Furthermore, the task at hand is achieved with a honing machine with the characteristics of the preamble of claim 1, in particular with the characteristics of claim 1, 2, or 3, wherein the horizontal honing station comprises a workpiece intake comprising a rotational device with a rotating axis parallel to the rotary table axis, with which the alignment of the workpiece can be changed. The honing in the horizontal honing station can be carried out with a different alignment than in the vertical honing station.

This means the horizontal honing unit can be more flexible positioned and aligned on the honing machine. With an immobile workpiece or a workpiece firmly positioned on the rotary table with a fixed alignment, the position and alignment of the horizontal honing unit would be specified by the orientation or alignment of the workpiece.

With an advantageous configuration of the honing machine, all workstations of the respective honing machine are arranged on a shared machine base. The alignment of the rotary table and at least one of all the workstations on the machine base improves the compactness and speed of the honing machine.

In another advantageous variant of the honing machine, the honing machine comprises at least two vertical honing stations. At least one vertical honing station comprises one vertical honing unit moveably arranged on a portal-like carrier via sliders. All vertical honing units can also be moveably arranged on the portal-like carrier via sliders. The use of multiple vertical honing stations and/or vertical honing units facilitates the simultaneous processing of multiple vertically aligned bores. It is also possible for a vertical honing station to comprise multiple vertical honing units, so that honing operations can be simultaneously performed in multiple vertically aligned bores in a workpiece in a vertical honing station. Accordingly, honing operations can be simultaneously performed in multiple vertically aligned bores in various workpieces in various vertical honing stations. The simultaneous carrying out of multiple honing operations reduces the overall processing time of the honing machine.

At least one of the workstations can be an empty station or a workstation for carrying out other processing operations, e.g., chamfering.

In another advantageous variant of the honing machine, the honing machine comprises four workstations. The first workstation is a loading and unloading station, where a workpiece to be honed is placed on the rotary table or removed from the rotary table.

A second workstation is designed as a first vertical honing station. In particular, it can be used for pre-honing.

A third workstation is designed as a horizontal honing station. The horizontal honing operations are carried out here.

A fourth workstation is designed as the second vertical honing station. It can be used for final honing.

The transport direction of the rotary table is from the first to the second, or rather the third to the fourth, workstation. After completing the fourth workstation, the workpiece returns to the first workstation. The number of workstations and their respective design, namely as a loading/unloading station, two vertical honing stations, one horizontal honing station, optimizes the total processing time of the workpieces through as many simultaneous operations as possible, and also facilitates a honing machine as compact as possible, which works precisely. In particular, such a division can advantageously integrate the moving or tilting of the workpiece in the horizontal honing station into the work cycle. This applies accordingly to the acceleration of the workpiece when it is being moved.

Furthermore, the task at hand is achieved by the invention's method for carrying out honing operations on orthogonally aligned bores in a workpiece with the characteristics of claim 8. The workpiece is moved during the honing in the horizontal honing station. In particular, the honing spindle of the horizontal honing unit is at least kept immobile in the direction of the translatory relative motion.

The movement of the workpiece can reduce the movement of the horizontal honing unit, or, if the horizontal honing unit is immobile, limited to the rotation of the honing spindle or a honing tool arranged at the honing spindle. This increases the precision with which the honing spindle or honing tool can be used during the honing processing. This results in a more precise overall result of the honing operation. The method steps described herein partially correspond to the structural designs of the honing machines described. The benefits listed herein are also present in the method steps.

Furthermore, the task at hand is achieved with a method with the characteristics of the preamble of claim 8, in particular with the characteristics of claim 8, wherein, in order to carry out the horizontal honing, the workpiece is moved away from the rotary table, and the honing is carried out outside of the rotary table, in particular wherein the workpiece is moved outside of the circular path where the rotary table moves the workpieces.

Because the honing is carried out outside of the rotary table, there is no transfer of unwanted vibrations and oscillations to the rotary table caused by the honing, or these are minimized. Other workpieces located on the rotary table are thus unaffected by these vibrations or oscillations. This improves the precision of the processing of the workpieces at the other workstations.

Furthermore, the task at hand is achieved with a method with the characteristics of the preamble of claim 8, in particular with the characteristics of claim 8 or 9, wherein the horizontal spindle axis runs along a processing direction. The translatory relative motion during the honing occurs along this axis. The processing direction is parallel to a direction extending radially through the rotary table axis, yet is spaced from the rotary table axis. In other words, the processing direction runs along a straight line that does not pass through the rotary table axis.

This means the horizontal honing unit can be more flexibly arranged and aligned. For example, two horizontal honing units can be positioned next to and parallel to one another. It is also possible to position a horizontal honing unit and a measuring station next to and parallel to one another. This accelerates the overall process.

The task at hand is also achieved with a method with the characteristics of the preamble of claim 8, in particular with the characteristics of claim 8, 9, or 10, wherein before the horizontal honing is carried out, the alignment of the workpiece is altered. It is also possible for the alignment of the workpiece to be altered during and/or after the horizontal honing.

This means the horizontal honing unit can be more flexible arranged and aligned. In the event of an immobile or firmly positioned workpiece, the position and alignment of the horizontal honing unit would be specified by the orientation or alignment of the workpiece.

BRIEF DESCRIPTION OF THE DRAWINGS

Further characteristics, details and advantages of the invention are apparent from the wording of the claims as well as from the following description of example embodiments based on the illustrations. These show:

FIG. 1 a top view of a honing machine described by the invention;

FIG. 2 a side view of the honing machine described by the invention as shown in FIG. 1;

FIG. 3 a top view of another example embodiment of a honing machine described by the invention, and

FIG. 4 a side view of the honing machine described by the invention as shown in FIG. 3.

DETAILED DESCRIPTION

In the following description, as well as in the figures, corresponding components and elements have the same reference sign. For the sake of clarity, not all references signs are listed in all figures.

FIG. 1 shows a top view of a honing machine 10 described by the invention for carrying out honing operations on orthogonally aligned bores in a workpiece 12. The honing machine 10 comprises a machine base 14 where a transport system 16 is located. The transport system 16 comprises a rotary table 18 that rotates around a vertical rotary table axis 20. Four workpiece intakes 22 are arranged on the rotary table 18, wherein each of the workpiece intakes 22 can receive one workpiece 12. Rotation of the rotary table 18 around the rotary table axis 20 transports the workpieces 12 on a circular path. The workpieces 12 are then led to the individual workstations. Four workstations are indicated by four workpieces 12. The workstation shown on the right in FIG. 1 is a horizontal honing station 24. The horizontal honing station 24 comprises a horizontal honing unit 26 comprising a honing spindle 28 with a honing tool. The honing spindle 28 or honing tool is aligned along a horizontal spindle axis 30. The horizontal honing operation is thus carried out along this horizontal spindle axis 30.

The honing machine 10 also comprises an actuator unit 32 positioned on the machine base 14 that can move the workpiece 12 back and forth along the horizontal spindle axis 30 via a track system. During operation the workpiece 12 is moved radially away from the rotary table 18 so that there is no more direct contact between the workpiece 12 and the rotary table 18, and the rotary table is essentially vibrationally disconnected from the workpiece. Such a disconnection of the workpiece 12 prevents the transfer of the vibrations and oscillations from the horizontal honing operations via the workpiece 12 to the rotary table 18 and thus to other workpieces 12 or workstations.

Before a horizontal honing operation is carried out on the workpiece 12, the workpiece 12 is aligned in the actuator unit 32 such that a horizontally aligned bore that is to be honed is arranged along the horizontal spindle axis 30. In this example embodiment, the horizontal honing unit 26 is firmly positioned on the machine basis 14 so that the honing spindle 28 is immovable along the horizontal spindle axis 30. The honing spindle 28 or honing tool only carries out a rotation during the horizontal honing operation. The workpiece 12 is moved back and forth along the horizontal spindle axis 30 via the actuator unit 32, while the honing spindle 28 or honing tool rotates so that the honing operation can be carried out on the bore previously aligned along the horizontal spindle axis 30. After completion of the horizontal honing operation, the workpiece 12 is returned to the workpiece intake 22 of the rotary table 18 and transported to the next workstation via rotation of the rotary table 18 around its vertical rotary table axis 20.

The individual workstations can be a loading and unloading station, a vertical honing station, a measuring station, or another horizontal honing station 24. For example, the workstation indicated on the left in FIG. 1 by the workpiece 12 can be a loading and unloading station, and the workstations indicated at the top and bottom of FIG. 1 via workpieces 12 can be vertical honing stations with vertical honing units (not pictured). In particular, the workstation indicated at the top of FIG. 1 by the workpiece 12 can be used for vertical pre-honing, and the workstation indicated at the bottom of FIG. 1 by the workpiece 12 can be used for vertical final honing. At least one of the workstations can also be a measuring station, with which the honing operations carried out at the respective bores can be evaluated and monitored. But it is also possible for the measurement to be conducted with a measuring unit 34 at a workstation that is not a measuring station.

The measuring unit 34 shown in FIG. 1 is arranged on the machine base 14 via sliders such that post-measuring of the horizontal bore is possible, while, for example, the workpiece 12 is located in the workstation for vertical shape honing (see above).

FIG. 2 shows a side view of the honing machine 10 described by the invention as shown in FIG. 1. It is clear that, in order to carry out the honing in the horizontal honing station 26, the workpiece 12 is radially moved outward away from the rotary table 18 in order to achieve the aforementioned disconnection of the workpiece 12 from the rotary table 18. Furthermore, the rotary table 18 in this example embodiment is an elevating rotary table. This means that the rotary table 18 can be lowered after transporting the workpieces 12 into the next respective workstation. The workpieces 12 then remain in the respective workstations and are no longer connected with the rotary table 18. The rotary table 18 is thus not a medium by which unwanted vibrations or oscillations generated in the individual workstations can be transferred between the individual workpieces 12 or workstations.

FIG. 3 shows a top view of another example embodiment of a honing machine 10 described by the invention. Here, too, are four workstations shown, indicated by four workpieces 12, similar to the previous example embodiment. In the example embodiment shown here, the horizontal honing unit 26 is positioned on the machine base 14 such that the horizontal spindle axis 30 does not run through the rotary table axis 20. Accordingly, the workpiece 12 must be aligned along this horizontal spindle axis 30 with its horizontally aligned bore. This is done with a rotational device not further explained herein.

In this example embodiment, the horizontal honing unit 26 is moveable via tracks so that the horizontal honing unit 26, and thus the honing spindle 28, can move back and forth along the horizontal spindle axis 30 with a honing tool. In order to carry out the horizontal honing operations, the honing spindle 28 is lowered into the workpiece 12 or the bore of the workpiece 12 to be honed by moving the horizontal honing unit 26 following alignment of the workpiece 12.

After completion of the horizontal honing operation, the workpiece 12 is once again rotated by the rotational device (not pictured) so that the honing operation can be evaluated and monitored by the measuring device 34. The rotated workpiece 12 and its alignment are shown in FIG. 3 with a thin, dashed line. The measuring device 34 is also moveably positioned along an axis on the machine base 14 via tracks. The horizontal honing and post-measuring can thus be carried out at the same workstation. A separate workstation for the post-measuring or post-monitoring of the horizontal honing operations is not necessary. Nevertheless, a measuring station may be provided as a workstation where only post-measuring is carried out.

Similar to the previous example embodiment, the individual workstations can be a loading and unloading station, a vertical honing station, a (additional) measuring station, or another horizontal honing station 24.

FIG. 4 shows a side view of the honing machine 10 described by the invention as shown in FIG. 3. In this example embodiment, too, the rotary table 18 is designed as an elevating rotary table in order to prevent the transfer/spread of unwanted oscillations or vibrations via the rotary table 18.

Claims

1. Honing machine for carrying out honing operations on orthogonally aligned bores in a workpiece, comprising:

a machine base;

at least one machine-internal transport system arranged on the machine base comprising a rotary table that rotates around a vertical rotary table axis and comprises multiple workpiece intakes which are arranged offset from one another in the circumferential direction at a radial distance from the rotary table axis such that a workpiece inserted into a workpiece intake can be successively moved along a circular path and passed through various workstations of the honing machine via rotation of the rotary table;

wherein at least one of the workstations is a vertical honing station comprising at least one vertical honing unit, which has a honing spindle designed for honing of a bore aligned along a vertical direction via a relative motion rotating around a spindle axis and translatory along the spindle axis, between the workpiece and the honing spindle, wherein the spindle axis is aligned parallel to the rotary table axis;

wherein further one of the workstations is a horizontal honing station comprising at least one horizontal honing unit, which has a honing spindle designed for honing of a bore aligned along a horizontal direction via a relative motion rotating around a horizontal spindle axis and translatory along the horizontal spindle axis, between the workpiece and this honing spindle,

characterized in that the honing machine comprises an actuator unit that is arranged and designed to carry out the honing in the horizontal honing station by moving the workpiece, wherein in particular the honing spindle of the horizontal honing unit is arranged immovably in the honing machine for carrying out the honing, or that the machine-internal transport system is designed such that, to carry out the honing in the horizontal honing station, the workpiece is moved away from the rotary table, and the honing is carried out outside of the rotary table, in particular wherein the workpiece is moved outside of the circular path where the rotary table moves the workpieces.

2. Honing machine according to claim 1,

characterized in that the horizontal spindle axis extends along a processing direction and the translatory relative motion occurs along this axis during the honing, wherein this processing direction is parallel to a direction extending radially through the rotary table axis, yet is spaced from the rotary table axis.

3. Honing machine according to claim 1, characterized in that there is a rotational device in the horizontal honing station, so that the alignment of the workpiece can be changed such that the processing in the horizontal honing station can be carried out with a different alignment of the workpiece than in the vertical honing station.

4. Honing machine according to claim 1,

characterized in that all workstations of the honing machine are arranged on the machine base.

5. Honing machine according to claim 1, characterized in that the honing machine comprises at least two vertical honing stations, wherein at least one vertical honing station comprises a vertical honing unit moveably arranged on a portal-like carrier via sliders, wherein the honing units of all vertical honing stations are moveably arranged on the carrier via sliders.

6. Honing machine according to claim 1, characterized in that the honing machine comprises a first workstation designed as a loading and unloading station,

a second workstation,

wherein this is a first vertical honing station for pre-honing,

a third workstation, wherein it is the horizontal honing station, and

a fourth workstation, wherein this is a second vertical honing station for the final honing or other processing, wherein the transport direction of the rotary table is from the first to the fourth workstation and back to the first workstation.

7. (canceled)

8. Method for carrying out honing operations on orthogonally aligned bores in a workpiece, wherein the method comprises the following steps:

receipt of the workpiece at a rotary table that rotates around a vertical rotary table axis; transportation of the workpiece successively between various workstations along a circular path via rotation of the rotary table;

wherein at least one of the workstations is a vertical honing station in which a bore aligned along a vertical direction is honed via a relative motion rotating around a spindle axis and translatory along the spindle axis, between the workpiece and honing spindle, wherein the spindle axis is aligned parallel to the rotary table axis;

wherein further one of the workstations is a horizontal honing station in which a bore aligned along a horizontal direction is honed via a relative motion rotating around a horizontal spindle axis and along the horizontal spindle axis, between the workpiece and honing spindle,

characterized in that

in order to carry out the honing in the horizontal honing station, the workpiece is moved, and the honing spindle of the horizontal honing unit is held immobile at least in the direction of the translatory relative motion, or that in order to carry out the horizontal honing, the workpiece is moved away from the rotary table and the honing is carried out outside of the rotary table, wherein the workpiece is moved outside of the circular path where the rotary table moves the workpieces.

9. Method according to claim 8,

characterized in that the horizontal spindle axis runs along a processing direction and the translatory relative motion during the honing occurs along this axis, wherein this processing direction is parallel to a direction extending radially through the rotary table axis, yet is spaced from the rotary table axis.

10. Method according to claim 8, characterized in that the alignment of the workpiece is changed before the horizontal honing.

11. (canceled)

12. Method according to claim 8,

characterized in that a honing machine according to claim 1 is used to carry out the method.