EP0936028B1 - Apparatus for superfinishing machined surfaces - Google Patents

Description

The invention relates to a device for superfinishing machined, especially finished or sanded Workpiece surfaces, with a clamping device for the workpiece, a finishing stone as a tool, a holder for the finishing stone, a multi-axis drive device to perform a multi-axis relative movement between the surface to be processed and the holder in one machining surface orthogonal plane, which by the coordinates X and Y is defined, and one Control unit for controlling the drive device, wherein the control unit input means for entering the Profiles of the surface to be processed as well as electronic Has computing means. Such a device according to the preamble of claim 1 is e.g. known from US-A-4,485,592. It is known that ground surfaces of Workpieces, especially of rolling bearings, in another Finished work step, which on the one hand Roughness of the surface is reduced, on the other hand the shape and Dimensional accuracy is increased. As a rule, at this finishing process down to 6 µm, in special cases even 50 µm and more material removed. Become flat surfaces processed with a flat finishing stone, the one in the plane the surface is moved. Become curved surfaces also finished with a finishing stone, the In this case, the working surface of the finishing stone is not even but the curvature of the surface to be machined is adjusted. During processing, the stone pivoted so that it is permanently flat on machined workpiece or on the workpiece to be machined Surface is applied. For this the finishing stone is in one Swiveled device clamped, the swivel axis in the The center of curvature of the surface to be machined lies. It has been shown that with such devices only a limited number of workpieces can be processed can. Workpieces with slightly curved surfaces, i.e. with surfaces whose radius of curvature is very large can not be processed with such devices because the swivel arm for swiveling the finishing stone in the Is usually too short. This is especially true for Angularly adjustable floating bearings and large spherical roller bearings. In addition, CNC processing machines are known with which Machining tools, e.g. Drills, turning tools and the like in the Space can be moved. Have such tools however point or line-shaped cutting edges, so that the Angular position of the tool relative to the workpiece it is determined by the rake angle that this rake angle however can be variable in relatively large areas. Such machines are not suitable for tools which the workpiece is not punctiform or linear flat, namely processed via a finishing stone. This finishing stone not only has to be in relation to the tool the X-Y plane but also exactly in its angular position be positioned so that the cutting surface of the Finishstones flat on the surface to be machined Surface of the workpiece rests.

The invention is therefore based on the object To provide device with which such Workpieces can be processed relatively easily.

This task is accomplished with a finishing device at the beginning mentioned type solved according to the invention in that the Holder by means of a swiveling device around the X-Y plane orthogonal virtual swivel axis can be swiveled is stored and that to the position of the finishing stone corresponding swivel angle of the holder over the Computing means can be determined and the swivel device from the control unit can be controlled.

With the device according to the invention, the finishing stone about the drive device not only in the X-Y plane process but also pivoted such that the Finish stone permanently on the surface to be processed Surface rests. The to every position of the finishing stone corresponding swivel angle is calculated using the computing means from the geometry of the surface to be machined or the profile of the workpiece. This requires in the rule of two points and the radius of curvature of the Surface. From this information the virtual Swivel angle calculated by which the finishing stone is only pivoted. Because this virtual Swivel angle a very large distance to finishing surface via the drive device in the X direction and in the Y direction procedure and in addition to an actual one Swivel axis swiveled. This movement in the plane as well Pivoting around the actual pivot axis corresponds a pivoting around the virtual pivot axis. The however, the actual pivot axis lies within the Finishing device, particularly within the Swivel device and is from a swivel bearing educated. With the device according to the invention can now workpieces can also be machined that are very large Radii of curvature have or a plane, too surface (the radius of curvature is infinite).

According to a preferred embodiment, the Swivel device integrated in the drive device. So the finishing stone is in via the drive device Move X and Y direction, which is done by the swivel device via the drive device is moved on which the holder for the finishing stone is provided. In addition, the swivel device the holder and thus the finishing stone swiveled.

However, there is also a possibility that the Swivel device is machine-proof, and in the A drive device is provided, which the holder for the finishing stone in two to each other orthogonal directions.

According to the invention, this swiveling device can be electrically e.g. via servo motors or the like, electromagnetic, can be activated hydraulically and / or pneumatically.

The device according to the invention is suitable for level and curved surfaces, in particular arcuate or toroidal curved Surfaces, as well as concave and convex Machining surfaces. In addition, surfaces be edited that are inclined so that the virtual Pan axis outside the plane of the rule annular component.

A further training provides that the holder and / or the Drive device a pressure device for the Has finishing stone. This pressure device holds the Finish stone permanently on the surface to be processed and drives it with a given force. On in this way the desired removal is achieved and the Compensation for wear of the finishing stone. Is preferred the pressure device is pneumatic or hydraulic loadable, the finishing stone also with spring force can be pressed onto the surface to be processed. A pneumatic device has the main advantage that the contact pressure is kept relatively constant relatively easily can be.

The device according to the invention is so in a variant executed that the actual pivot axis in the Contact level of the finishing stone and the one to be machined Surface lies. In a preferred embodiment the actual swivel axis lies between the Touch level and the location of the virtual swivel axis. The position of the actual pivot axis is preferred adjustable with regard to the surface to be processed.

Figur 1

eine Seitenansicht der erfindungsgemäßen Finishvorrichtung;

Figur 2

eine Draufsicht in Richtung des Pfeils II gemäß Figur 1; und

Figur 3

mehrere Werkstücke, welche mit der Vorrichtung bearbeitet werden können.

Further advantages, features and details of the invention emerge from the subclaims and the following description in which a particularly preferred exemplary embodiment is described in detail with reference to the drawing. The drawing shows:

Figure 1

a side view of the finishing device according to the invention;

Figure 2

a plan view in the direction of arrow II of Figure 1; and

Figure 3

several workpieces that can be processed with the device.

FIG. 1 shows an overall designated 1 Finishing device with a machine housing 2, in which Supply units, drives, a control unit 23 with Computing means and the like for the device 1 housed are. There is a carriage 3 on the machine housing 2 the one on a vertical guideway 4 in the Y direction (Double arrow 5) is movable. There is 3 on this carriage attached to a support arm 6, a swivel device 7, on which a swivel arm 8 about a swivel axis 9 is pivotally mounted. This swivel device 7 is Can be moved in the vertical direction via the carriage 3. Between the swivel device 7 and the support arm 6 there is another carriage 10, over which the Swivel device 7 in an orthogonal to the plane of the drawing Direction, namely in the direction of the x-axis, is movable.

There is a inside the machine housing 2 Rotary drive with an axis of rotation 11, via which one Face plate 12 can be rotated. At this Face plate 12 is a workpiece via holding devices 13 14 attached, which are rotated about the axis of rotation 11 can. The axis of rotation 11 and the central axis lie here of the workpiece 14 coaxially with each other. The swivel arm 8 has the shape of a U open at the bottom and engages its free end into the workpiece 14. At this Free end 15 is a holder 16 which one Finish stone 17 picks up. This finishing stone 17 attacks of the inner surface 18 to be machined (FIG. 2). On the finishing stone 17 lies flat over this inner surface 18 on. So he has the same on his contact surface Curvature like the inner surface 18.

The two slides 3 and 10 form one Drive device 22 for the holder 16 and the Finish stone 17 in the X direction 20 and in the Y direction 5.

In Figure 2, the finishing device 1 is in plan view in Direction of arrow II shown in Figure 1. It is clearly recognizable how the finishing stone 17 on the Inner surface 18 abuts. The holder 16 has one Pressure device 19, via which the finishing stone 17 with constant force is pressed onto the inner surface 18. The pivoting device 7 in is moved over the slide 10 Direction of double arrow 20, i.e. Move in the X direction. The two slides 3 and 10 thus allow the descent the inner surface 18 of the workpiece 14 in the x-y plane 21. About the pivoting device 7 is also the Finished stone 17 pivoted about the pivot axis 9, so that it is permanently flat on the inner surface 18 is applied. The pivot axis 9 is at a distance from Inner surface 18. When using a different shape Swivel arm 8, however, there is also the possibility that the pivot axis 9 exactly in the interface between the inner surface 18 and the finishing stone 17 comes.

With the finishing device 1 according to the invention any workpieces with flat or cylindrical ones Surfaces are processed. They usually have However, workpieces have surfaces that are cutouts Represent torus. In Figure 3 there are several outer rings (top) and inner rings (bottom) of various roller bearings shown. Figure 3a shows an angle adjustable Floating bearing, the inner surface 18 of the finishing stone 17th is processed. This finishing stone 17 is in the X direction Move 20 (vertical) and 5 (horizontal) in the Y direction and the swivel device 7 and the swivel angle α pivoted. This also applies to the outer surface 18 'of the The inner ring.

Figure 3b shows a spherical roller bearing in which the Outer ring compared to Figure 3a a smaller one Has radius of curvature. The inner ring has in this Case two inner surfaces 18 'to be machined. The figure 3c shows an axial spherical roller bearing with inclined curved surfaces 18 and 18 '. In addition, the Inner ring another surface to be machined 18 '', which is processed with a finishing stone 17 '.

Figure 3d shows a tapered roller bearing with tapered Surfaces 18 and 18 ', in which case the finishing stone is only inclined, but is not pivoted. Also here the inner ring has a second one to be machined Surface 18 '', which is finished with a finishing stone 17 ' is processed.

Figure 3e shows a cylindrical roller bearing cylindrical surfaces 18 and 18 ', here the Finishing stone 17 is neither inclined nor pivoted.

Figure 3f shows a deep groove ball bearing in which the Surfaces 18 and 18 'have very small radii of curvature have so that the finishing stone 17 in the X direction 20 and Y direction 5 is almost not moved, but the Swivel angle α is relatively large.

With the finishing device 1 according to the invention can also Thrust bearings or thrust ball bearings are machined, whereby in the case of thrust bearings, the surface to be machined is flat. Overall, it can be stated that, as in FIG shown, flat surfaces and cut-out surfaces of a Torus can be edited.

Claims (6)

1. A device for superfinishing of treated, in particular finished or ground, surfaces (18) of work pieces (14), having a clamping device (13) for the workpiece (14), a finishing block (17) as the tool, a holder (16) for the finishing block (17), a multi-axis drive device (22) for performing a multi-axis relative movement between the surface (18) to be treated and the holder (16) in a plane (21) which is orthogonal in respect to the surface (18) to be treated and is defined by the coordinates X and Y (20 and 5), as well as a control unit for controlling the drive device (22), wherein the control unit (23) has input means for inputting the profile of the surface (18) to be treated, and the control unit (23) has electronic calculating means, characterized in that by means of a pivoting device (7) the holder (16) is seated pivotable around a virtual pivot axis which is orthogonal in respect to the X - Y - plane (21), and that the pivot angle (α) of the holder (16) corresponding to the position of the finishing block (17) can be determined by means of the calculating means, and that the pivoting device (7) can be controlled from the control unit (23).
2. The device in accordance with claim 1, characterized in that the pivoting device (7) is integrated into the drive device (22).
3. The device in accordance with one of the preceding claims, characterized in that the pivoting device (7) can be electrically, electro-magnetically, hydraulically and/or pneumatically activated.
4. The device in accordance with one of the preceding claims, characterized in that the holder (16) and/or the drive device (22) has a contact pressure device (19) for the finishing block (17).
5. The device in accordance with claim 4, characterized in that the contact pressure device (19) can be charged pneumatically or hydraulically, or that it presses the finishing block (17) at the surface (18) to be worked by means of a spring force.
6. The device in accordance with one of the preceding claims, characterized in that the actual pivot axis (9) is located in the tangent plane between the finishing block (17) and the surface (18) to be treated, or lies between the tangent plane and the location of the virtual pivot axis.

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