Method and device for processing a hard-coated workpiece surface of a rotationally symmetrical workpiece

Abstract

The present invention relates to a method and a device for processing a hard-coated workpiece surface of a rotationally symmetrical workpiece (1) with at least one grinding wheel, wherein the method comprises the following steps: driving the workpiece (1) into a rotational motion around a workpiece axis of rotation (1.1), driving a grinding wheel (2a) into a rotational motion around a grinding wheel axis of rotation (2a.1), angulating the grinding wheel axis of rotation (2a.1) and the workpiece axis of rotation (1.1) to each other so that the grinding wheel axis of rotation (2a.1) and the workpiece axis of rotation (1.1) are not parallel, processing the workpiece surface with the grinding wheel (2a), wherein the grinding wheel (2a) is in contact with the workpiece surface.

Claims

1. A method for processing a hard-coated and planar workpiece surface of a rotationally disk-shaped symmetrical workpiece (1) with at least one grinding wheel, comprising the following steps: driving the workpiece (1) into a rotational motion around a workpiece axis of rotation (1.1), driving a grinding wheel (2a) into a rotational motion around a grinding wheel axis of rotation (2a.1), angulating the grinding wheel axis of rotation (2a.1) and the workpiece axis of rotation (1.1) to each other so that the grinding wheel axis of rotation (2a.1) and the workpiece axis of rotation (1.1) are not parallel, processing the workpiece surface with the grinding wheel (2a), wherein the grinding wheel (2a) is in contact with the workpiece surface, wherein an angle of incidence between the grinding wheel axis of rotation (2a.1) and the workpiece axis of rotation (1.1) is changed during the processing step while the workpiece surface is in contact with the grinding wheel.

2. The method according to claim 1, wherein the grinding wheel (2a) and the workpiece (1) are moved relative to each other in a plane perpendicular to the workpiece axis of rotation (1.1) during the processing step.

3. The method according to claim 1, wherein a second hard-coated and planar workpiece surface of the rotationally symmetrical workpiece (1) is processed with a second grinding wheel (2b) that rotates around a second grinding wheel axis of rotation (2b.1), wherein the second grinding wheel axis of rotation (2b.1) is angulated to the workpiece axis of rotation (1.1) in such a way that the workpiece axis of rotation (1.1) and the second grinding wheel axis of rotation (2b.1) are not parallel.

4. The method according to claim 3, wherein an angle of incidence between the second grinding wheel axis of rotation (2b.1) and the workpiece axis of rotation (1.1) is changed during the processing step while the second workpiece surface is in contact with the second grinding wheel.

5. The method according to claim 1, wherein the grinding wheel (2a) is dressed and/or sharpened during the processing step.

6. The method according to claim 1, wherein the workpiece axis of rotation (1.1) and the grinding wheel axis of rotation (2a.1) are aligned parallel to each other in a subsequent processing step.

7. The method according to claim 1, wherein the workpiece axis of rotation (1.1) or the grinding wheel axis of rotation (2a.1) can be swiveled around one rotational degree of freedom or around two rotational degrees of freedom for angulation purposes.

8. The method according to claim 1, wherein at least the following steps are performed in the indicated sequence: i) angulating grinding wheel axes of rotation (2a.1, 2b.1) of two grinding wheels (2a, 2b) to the workpiece axis of rotation (1.1), ii) relatively moving the workpiece to the angulated grinding wheels (2a, 2b) during a first processing step, iii) aligning grinding wheel axes of rotation (2a.1, 2b.1) to the workpiece axis of rotation (1.1), so that the grinding wheel axes of rotation (2a.1, 2b.a) and the workpiece axis of rotation (1.1) are parallel, iv) processing the workpiece in a second processing step, during which the grinding wheel axes of rotation (2a.1, 2b.a) and the workpiece axis of rotation (1.1) are parallel.

9. A device for processing a hard-coated and planar workpiece surface of a rotationally disk-shaped symmetrical workpiece (1), comprising: a workpiece driving device (3) for generating a rotational motion around a workpiece axis of rotation (1.1), at least one grinding wheel driving device (4a, 4b) for generating a rotational motion around at least one grinding wheel axis of rotation (2a.1, 2b.1) of at least one grinding wheel (2a, 2b), at least one infeed device (5) for bringing the at least one grinding wheel (2a, 2b) into contact with the workpiece surface, and at least one angulating device (6a, 6b) for angulating the at least one grinding wheel axis of rotation (2a.1, 2b.1) and the workpiece axis of rotation (1.1) to each other, so that the at least one grinding wheel axis of rotation (2a.1, 2b.1) and the workpiece axis of rotation (1.1) are not parallel, and a controller configured to change an angle of incidence between the grinding wheel axis of rotation (2a.1) and the workpiece axis of rotation (1.1) during a processing operation while the workpiece surface is in contact with the grinding wheel.

10. The device according to claim 9, wherein the at least one infeed device (5) is set up in such a way that the at least one grinding wheel (2a, 2b) and the workpiece (1) can be moved relative to each other during the processing operation in a plane perpendicular to the workpiece axis of rotation (1.1).

11. The device according to claim 9, further comprising a second grinding wheel driving device (4b) for generating a rotational motion around a second grinding wheel axis of rotation (2b.1) and a second angulating device (6b) for angulating the second grinding wheel axis of rotation (2b.1) to the workpiece axis of rotation (1.1), so that the second grinding wheel axis of rotation (2b.1) and the workpiece axis of rotation (1.1) are not parallel.

12. The device according to claim 9, comprising at least one conditioning device (7), which can be brought from an initial position into a conditioning position, so that the at least one grinding wheel (2a, 2b) can be conditioned during the processing operation.

13. The device according to claim 9, wherein the at least one angulating device (6a, 6b) is designed in such a way that the workpiece axis of rotation (1.1) or the at least one grinding wheel axis of rotation (2a.1, 2b.1) can be swiveled by exactly one rotational degree of freedom or by several rotational degrees of freedom.

14. The device according to claim 9, wherein the controller is set up to implement the following steps: driving the workpiece into the rotational motion around the workpiece axis of rotation, driving the at least one grinding wheel into the rotational motion around the at least one grinding wheel axis of rotation, angulating the at least one grinding wheel axis of rotation and the workpiece axis of rotation to each other so that the at least one grinding wheel axis of rotation and the workpiece axis of rotation are not parallel, processing the workpiece surface with the at least one grinding wheel, wherein the at least one grinding wheel is in contact with the workpiece surface.

Description

(1) The invention along with the technical environment will be exemplarily explained below based on the figures, wherein the figures only show a preferred embodiment. Shown schematically on:

(2) FIG. 1: is a device for processing a hard-coated brake disk,

(3) FIG. 2: is a detailed view of the device with an angulating device for a grinding wheel,

(4) FIG. 3: is a sectional view through the angulating device,

(5) FIG. 4: is another sectional view through the angulating device,

(6) FIG. 5: is a detailed view of the device during the conditioning of the grinding wheel, and

(7) FIG. 6: is a schematic illustration of the procedure for processing the brake disk.

(8) The device shown on FIG. 1 for processing a hard-coated workpiece 1 designed as a brake disk comprises a workpiece driving device 3, with which the brake disk 1 can be driven into a rotational motion around a workpiece axis of rotation 1.1. The device additionally comprises an infeed device 5, with which the brake disk 1 and the workpiece driving device 3 can be moved in a horizontal direction and in a vertical direction.

(9) The device additionally comprises a first grinding wheel driving device 4a, which is mounted in a first angulating device 6a, and can be used to drive a first grinding wheel 2a into a rotational motion around a grinding wheel axis of rotation 2a.1. The device additionally has a second grinding wheel driving device 4b, which is mounted in a second angulating device 6b, and can be used to drive a second grinding wheel 2b into a rotational motion around a second grinding wheel axis of rotation 2b.1. The angulating devices 6a, 6b will still be explained in detail with reference to FIGS. 2 to 4.

(10) The device additionally comprises a first conditioning device 7a, which can be brought into a conditioning position from an initial position, and used to dressed the grinding wheels 2a, 2b. The device additionally comprises a second conditioning device 7b, which likewise can be brought into a conditioning position from an initial position, and used to sharpen the grinding wheels 2a, 2b.

(11) The first angulating device 6a and a first grinding wheel driving device 4a mounted therein will now be explained in more detail with reference to FIGS. 2 to 4, wherein reference is made to the fact that the second grinding wheel driving device 4b and the second angulating device 6b have an identical structural design. The first angulating device 6a comprises an inner bearing sleeve 6a.3, in which the driving device 4a for generating a rotational motion of the first grinding wheel 2a is arranged. The inner bearing sleeve 6a.3 is mounted in a second bearing sleeve 6a.4 so that it can swivel around a first swivel axis 6a.1, while the second bearing sleeve 6a.4 is mounted in an outer sleeve 6a.5 so that it can swivel around a second swivel axis 6a.2. The first grinding wheel driving device 4a, and hence also the first grinding wheel axis of rotation 2a.1, can thus be swiveled around two rotational degrees of freedom. Provided for this purpose is a first angulating device 6a.1i, with which the inner bearing sleeve 6a.3 can be swiveled around the first swivel axis 6a.1. Additionally provided is a second angulating drive 6a.2i, with which the second bearing sleeve can be swiveled around the second swivel axis 6a.2. However, the invention can also preferably only be realized with a swivel axis, and in particular with an accompanying angulating drive.

(12) The first angulating device 6a and the second angulating device 6b can be fed in by undepicted drives in at least the horizontal direction.

(13) In order to process the brake disk 1, both the brake disk 1 and the grinding wheels 2a, 2b are rotationally driven, wherein the grinding wheels 2a, 2b are each brought into contact with a side of the brake disk 1. It is now proposed that, while processing the brake disk 1, the grinding wheels 2a, 2b be angulated in opposite directions in such a way that the first grinding wheel axis of rotation 2a.1 and the second grinding wheel axis of rotation 2b.1 not be aligned parallel to the workpiece axis of rotation 1.1. Such a nonparallel angulation of the grinding wheels 2a, 2b can take place by means of the angulating devices 6a, 6b.

(14) FIG. 6 shows an especially preferred procedure, to which the invention is not confined. The grinding wheels 2a, 2b are initially aligned with the angulating devices 6a, 6b in such a way that the first grinding wheel axis of rotation 2a.1 and the second grinding wheel axis of rotation 2b.1 are not parallel to the workpiece axis of rotation 1.1 (see upper image on FIG. 6). In addition, the brake disk 1 and the grinding wheels 2a, 2b are angulated to each other in a horizontal direction in such a way that the brake disk is located at the height between the two grinding wheels 2a, 2b.

(15) In the following (see upper and middle image on FIG. 6), the brake disk 1 and the grinding wheels 2a, 2b are moved toward each other in a horizontal direction in such a way that the angulated grinding wheels 2a, 2b each come into contact with a workpiece surface of the hard-coated brake disk 1 to be processed, and process the workpiece surfaces. The linear motion that takes place along the arrows 8a can also be referred to as a peeling motion. During the processing operation, then, both the brake disk 1 and the grinding wheels 2a, 2b are driven around their respective axes of rotation, and each grinding wheel 2a, 2b is in contact with the workpiece surfaces to be processed by it. The angulation of the grinding wheels 2a, 2b to the brake disk 1 reduces the contact surface between the respective grinding wheel 2a, 2b and the accompanying workpiece surfaces (vis--vis a parallel angulation), so that a higher pressure is present between the grinding wheel 2a, 2b and brake disk 1 in the contact zone at an identical external force. As a consequence, the brake disk 1 can be processed with a high ablation rate at reduced process forces.

(16) At the end of the peeling motion 8a, a piercing motion can take place along the arrows 8b, during which the grinding wheels 2a, 2b are moved toward the brake disk 1 parallel to the workpiece axis of rotation 1.1. In order to further improve the surface quality (dimensional accuracy, roughness) of the brake disk 1, the grinding wheel axes of rotation 2a.1, 2b.1 are initially aligned parallel to the workpiece axis 1.1 by a swiveling motion (denoted by arrows 8c) (see middle image on FIG. 6). In an additional processing step (see lower image on FIG. 6), a classic plan processing of the brake disk 1 takes places, during which the workpiece surface of the brake disk 1 to be processed and the end faces of the grinding wheels 2a, 2b used for processing are aligned parallel to each other. In order to correct a change in process force caused by the ablation, the brake disks 2a, 2b can be moved toward the brake disk 1 parallel to the workpiece axis of rotation 1.1 along the arrows 8d during this last processing step.

(17) As may also be discerned from FIG. 5, both the first conditioning device 7a for dressing the grinding wheels 2a, 2b and the second conditioning device 7b for sharpening the grinding wheels 2a, 2b are brought to a conditioning position in which the conditioning devices 7a and 7b abut against one of the grinding wheels 2a, 2b, while the brake disk 1 is being processed with the grinding wheels 2a, 2b. The grinding wheels 2a, 2b are thus conditioned during the processing operation.

REFERENCE LIST

(18) 1 Workpiece 1.1 Workpiece axis of rotation 2a First grinding wheel 2a.1 First grinding wheel axis of rotation 2b Second grinding wheel 2b.1 Second grinding wheel axis of rotation 3 Workpiece driving device 4a First grinding wheel driving device 4b Second grinding wheel driving device 5 Infeed device 6a First angulating device 6a.1 First swivel axis 6a.2 Second swivel axis 6a.1i First angulating drive 6a.2i First angulating drive 6a.3 Inner bearing sleeve 6a.4 Second bearing sleeve 6a.5 Outer sleeve 6b Second angulating device 7a First conditioning device 7b Second conditioning device 8a Peeling motion 8b Piercing motion 8c Aligning motion 8d Corrective motion