EP0248983A1 - Method and apparatus for rolling profiles in cylindrical work pieces - Google Patents

Abstract

For the transverse rolling of a profiled workpiece (10), for example a gearwheel, rolling jaws (1, 2) are movably mounted on tool carriers (5, 6). Both tool carriers (5, 6) are mounted jointly on two crankshafts (18, 19) on mutually offset crank pins (20, 21, 22, 23) and are driven to perform synchronous movements in opposite directions. Separately from this, the rolling jaws (1, 2) are driven to perform tangential rolling movements. <IMAGE>

Description

The invention relates to a method for transverse rolling of profiled rotation profiles, in particular gear wheels, by means of rolling jaws which are driven by a feed movement composed of a radial feed component and a tangential rolling component to form a rolling movement on the workpiece.

The known rolling processes for the production of profiled rotary profiles, in particular gear wheels (DIN 8583), have in common that the rolling jaws are driven in a lifting movement in which they deform the workpiece material. The tool surfaces engaging with the workpiece can form, for example, an external toothing, a straight toothed rack or an internal toothing. The penetration process of the individual tool teeth into the workpiece material depends on the one hand on the tool geometry and on the other hand on the stroke movement of the tool.

Each tool tooth penetrates the workpiece several times during the cyclical machining process. With increasing deformation of the workpiece, not only does the workpiece surface in contact with the tool increase; there is also increasing solidification of the workpiece material. Both factors result in an increased resistance to the penetration of the tool tooth. In addition, different volumes of material are deformed with each penetration process. This has a significant impact on the mechanical properties of the shaped workpiece tooth and leads to errors in the resulting tooth geometry.

The engagement of the tool toothing in the workpiece takes place in the known methods according to the theoretically predetermined rolling ratios of toothings in which the tooth penetration path is a cycloid; it is completely ignored here that the actual engagement conditions as a result of the deformation processes deviate significantly from these theoretical engagement relationships.

This also applies to a known method of the type mentioned (DE-PS 19 05 949). A revolving stroke movement of the tools is achieved by mounting each roller jaw on two synchronously driven crankshafts. However, this type of tool drive does not allow adaptation to the particular requirements of the shaping process.

The object of the invention is therefore to design a method of the type mentioned at the outset in such a way that an optimal adaptation to the respective requirements of the deformation process is made possible.

This object is achieved in that each roller jaw is driven to a tangential rolling movement, which is controlled separately by the radial feed movement. This makes it possible to use these two tool movements, namely the tangential rolling movement and the radial feed movement, as a function of the to optimally control the respective penetration state. For the first time, this not only takes into account the workpiece geometry aimed for as the final state, but also the flow processes of the material in every intermediate state between the first tool intervention and the completion of the profile to be created.

The radial feed movement and the tangential rolling movement are preferably controlled in such a way that approximately the same material volumes are deformed in each unit of time. It has been shown that the control criterion of the constant deformation volumes leads to particularly good work results, in particular with regard to the manufacturing accuracy, but also the tool and machine stress.

If one speaks in this connection of the separate control of the tangential rolling movement and the radial feed movement, it should be noted that this does not have to be a purely tangential rolling movement and / or a purely radial feed movement. In many cases, the radial feed movement will still have a tangential movement component, as is already the case, for example, with the known crankshaft drive of the rolling jaws, and the tangential rolling movement will have a radial movement component, for example if the rolling jaws are guided on a curved path.

According to a preferred embodiment of the invention, the radial feed movement of all the rolling jaws takes place continuously and synchronously and the tangential rolling movement of each rolling jaw is controlled separately. The control process is considerably simplified in that the control intervention takes place depending on the deformation conditions only with the tangential drive of the rolling jaws, but not with the radial drive.

The invention further relates to an advantageous device for performing the method. Starting from a known device (DE-PS 19 05 949) with at least two rolling jaws, each of which is received on a tool carrier, which is mounted on eccentric crank pins of two synchronously driven crankshafts and can be driven in a circular movement parallel to itself Device according to the invention, characterized in that the rolling jaws are movably mounted on the tool carriers and are each connected to a controllable drive device, and that both tool carriers are mounted on crankshafts, each offset from one another by 180 °, in each case on two crankshafts.

The mounting of the two tool carriers on the two crankshafts not only achieves a machine structure that is considerably simpler than the known device; the machine structure is also much more stable and stiffer, because the force flow of the considerable forces occurring during the deformation process is closed in a short way; It should be emphasized here in particular that the power flow is not conducted via the bearing of the crankshafts on the machine frame, but is short-circuited in the two tool carriers. This largely prevents the opposing rolling jaws from springing open during the shaping process; This is the only way to achieve a control of the tangential rolling movement of the rolling jaws that is adapted to the deformation process.

The drive linkage of both tool carriers via two common crankshafts ensures precise synchronization easily and without play.

Further advantageous embodiments of the inventive concept are the subject of further dependent claims.

• Fig. 1 in stark schematisierter Darstellungsweise eine Vorrichtung zum Querwalzen von profilierten Rota­tionsprofilen,
• Fig. 2 einen horizontalen Schnitt durch eine konstruktive Ausführungsform einer derartigen Vorrichtung,
• Fig. 3 einen Schnitt längs der Linie III-III in Fig. 2 und
• Fig.4-7 in jeweils um 90° zueinander versetzten Dreh­stellungen der Kurbelwellen in vereinfachter Dar­stellungsweise eine Vorrichtung zum Querwalzen von profilierten Rotationsprofilen, wobei jeweils die Darstellung a) einen horizontalen Schnitt ähnlich der Fig. 2, die Darstellung b) eine Stirn­ansicht und die Darstellung c) eine räumliche, auseinandergezogene Anordnung der wesentlichen Teile der Vorrichtung zeigt.

The invention is explained in more detail below using exemplary embodiments which are illustrated in the drawing:

• 1 in a highly schematic representation, a device for transverse rolling of profiled rotation profiles,
• 2 shows a horizontal section through a constructive embodiment of such a device,
• Fig. 3 is a section along the line III-III in Fig. 2 and
• Fig. 4-7 in each case offset positions of the crankshafts by 90 ° to each other in a simplified representation, a device for transverse rolling of profiled rotation profiles, the representation a) a horizontal section similar to FIG. 2, the representation b) an end view and the representation c) shows a spatial, exploded arrangement of the essential parts of the device.

According to the highly schematic representation according to FIG. 1, two rolling jaws 1, 2 designed as flat jaws, which on one side have straight tool teeth 3 or 4, are each received on a tool carrier 5 or 6. They are guided on linear guideways 7 and 8 respectively. The two tool carriers 5, 6 are mounted on a machine frame 9 such that they can be moved relative to one another. The rolling jaws 1, 2 are in engagement with a workpiece 10 arranged therebetween, which is mounted in a bearing 11 fixed to the frame and can be moved axially, this axial movement even being the main movement of the forming process.

A drive device 12 drives the two tool carriers 5, 6 synchronously with an opposite, radial feed movement. In each case a separate drive device 13 or 14 drives the rolling jaws 1 or 2 along the guideways 7 or 8 for tangential rolling movements.

The drive devices 12, 13 and 14 are controlled by a control device 15 in such a way that the tool carriers 5, 6 carry out their radial feed movement continuously and synchronously, preferably in cyclical movement sequences. The drive devices 13, 14 are controlled such that the tangential rolling movements of the rolling jaws 1, 2 are controlled synchronously with the cyclical radial feed movement, but as a function of the respective stage of the deformation process.

1 only serves to explain the control and movement sequence, the following FIGS. 2 to 7 show a device for carrying out the method according to the invention in a constructive embodiment.

The two tool carriers 5 and 6 carry the rolling jaws 1 and 2 on the two parallel, vertical guide tracks 7 and 8, which are provided with roller bearings 16, 17 in the exemplary embodiment shown. Each tool carrier 5 and 6 is on two common crankshafts 18, 19 mounted, which can be driven synchronously, for example, by a gear 20 only indicated in FIG. 2. Further possibilities are the crankshaft gears connecting the two crankshafts 18, 19 or two separate drives on the two crankshafts 18, 19, the two tool carriers effecting the forced synchronization as crankshaft gears. Each tool carrier 5 or 6 is mounted on each crankshaft 18 or 19 on an eccentric crank pin 20, 21 or 22, 23. The two crank pins 20, 22 and 21, 23 of each crankshaft 18 and 19 are offset from one another by 180 °.

If the crankshafts 18, 19 are driven synchronously and in the same direction, both tool carriers 5, 6 each perform angularly synchronous movements symmetrically with respect to one another by 180 °, all points of the tool carriers 5, 6 moving parallel to one another on circular paths whose radius is equal to the eccentricity of the Crank pin is 20 to 23. The drive devices 13 and 14 (FIG. 3) drive the rolling jaws 1, 2 designed as flat jaws for tangential rolling movements. These tangential rolling movements take place at the beginning of the forming process, i.e. if the division of the toothing to be produced is determined, asymmetrical to each other.

In the central area of the deformation process, i.e. If the profile to be produced is already partially shaped, the tangential rolling movements of the rolling jaws 1, 2 are preferably carried out symmetrically to one another. At this stage of the deformation process, however, the tooth profile produced would always be asymmetrical or unequal if the rolling motion was always the same. This can be prevented by the tangential rolling movement of the rolling jaws 1, 2 taking place in the opposite direction during the subsequent movement cycle of the tools.

The two crankshafts 18, 19 are each mounted on the frame in two bearing blocks 24. A central bore 25 in each tool carrier 5 or 6 enables the axial insertion and advancement of the workpiece 10.

4 to 7 show four successive positions of the previously described machine parts during a single one of several successive machining cycles.

4 shows the crankshafts 18, 19 in the angular position 0 °, in FIG. 5 in the angular position 90 °, in FIG. 6 in the angular position 180 ° and in FIG. 7 in the angular position 270 °. The resulting positions of the two tool carriers 5, 6 and - in each case in the representations a) and b) - the radial positions of the rolling jaws 1, 2 relative to the workpiece 10 can be seen.

For the sake of simplicity of illustration, the roller jaws 1, 2 are omitted in the illustrations c); the tool carriers 5, 6 and the respective front bearing blocks 24 are shown partially cut away.

Instead of the illustrated design of the rolling jaws 1, 2 as flat jaws and / or the linear design of the guideways 7, 8, rolling jaws with curved machining surfaces, in particular concave or convex circular arcs, can also be selected. It is also possible to accommodate the rolling jaws in rotary bearings on the tool carriers 5, 6 and to design the drive devices 13, 14 as rotary drives, while in the illustrated exemplary embodiments only translatory drives were indicated for this purpose, which can be hydraulic cylinders, rack drives or spindle drives, for example.

The separate control of the three drive devices 12, 13 and 14 makes it possible to achieve significantly better workpiece geometries than known methods and devices. In addition to the favorable influence on the forming process itself, the subsequent calibration process is of great importance.

Examples of the machining of externally profiled, massive workpieces have been described. Instead, it is also possible to produce internally profiled rotation profiles, for example internally toothed sleeves, only a corresponding design of the rolling jaws being necessary. Even thin-walled workpieces can be profiled on the inside and outside at the same time, a profiled mandrel being used for the inner profile.

Claims (10)

1. A method for transverse rolling of profiled rotary profiles, in particular gears, by means of rolling jaws which are driven by a feed movement composed of a radial feed component and a tangential rolling component to form a rolling movement on the workpiece, characterized in that each rolling jaw (1, 2) is tangential Rolling movement is driven, which is controlled separately from the radial feed movement. 2. The method according to claim 1, characterized in that the control of the radial feed movement and the tangential rolling movement takes place in such a way that approximately the same material volumes are deformed in each time unit. 3. The method according to claim 1, characterized in that the radial feed movement of all the rolling jaws (1, 2) takes place continuously and synchronously and that the tangential rolling movements of each rolling jaw (1, 2) are controlled separately. 4. The method according to claim 3, characterized in that in the control of the tangential rolling movement of each roll jaw (1, 2), a tangential movement component already carried out together with the radial feed movement is taken into account. 5. The method according to any one of claims 1 to 4, characterized in that the tangential rolling movements of the rolling jaws (1, 2) are controlled synchronously with the cyclical radial feed movement. 6. Apparatus for carrying out the method according to one of claims 1 to 5 with at least two rolling jaws, each of which is received on a tool carrier, which is mounted on eccentric crank pins of at least two synchronously driven crankshafts and can be driven in a circular movement parallel to itself, characterized in that the rolling jaws (1, 2) are movably mounted on the tool carriers (5, 6) and are each connected to a controllable drive device (13, 14) and in that both tool carriers (5, 6) are each mounted on both crankshafts (18 , 19) are mounted on crank pins (20, 22 and 21, 23), respectively, which are offset by 180 °. 7. The device according to claim 6, characterized in that the rolling jaws (1, 2) on the tool carriers (5, 6) on rectilinear guideways (7, 8) are mounted. 8. The device according to claim 7, characterized in that the rolling jaws (1, 2) are flat jaws. 9. The device according to claim 6, characterized in that the rolling jaws are each received in a rotary bearing on the tool carrier (5, 6). 10. The device according to claim 6, characterized in that the crankshafts (18, 19) can be driven at a constant speed and that a control device (15), the drive devices (13, 14) of the two rolling jaws (1, 2) synchronously, but separately controls each other depending on a predetermined control function.

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