Device for finishing rolling elements

Abstract

Device (10) for finishing rolling elements (12), comprising a pair (28) of rollers (32, 34) which are driven to rotate about respective roller axes (36, 38), which rollers jointly cause the rolling element (12) to rotate about a rolling element axis (14) through contact of their respective roller surfaces (40, 42) with the outer surface (48) of a rolling element (12) to be finished, comprising a finishing tool (50) which has an active surface (52) which can be fed along a feed axis (54) in the direction of the outer surface (48) of the rolling element (12) and can be pressed against the outer surface (48), comprising an oscillation drive (60) for driving the finishing tool (50) along an oscillation axis (62), wherein, viewed along the feed axis (54), the oscillation axis (62) and the Rolling body axis (14) intersect each other and are arranged at an angle to each other, characterized in that a blocking device (64) is provided,which blocks a transport movement of the rotating rolling body (12) along a transport axis (20) parallel to the roller axes (36, 38) against a transport direction directed from an inlet (22) to an outlet (24) of the device (10).

Description

The invention relates to a device for finish machining of rolling bodies, having a pair of rollers which are driven rotatably about respective roller axes and which, together by contact of their respective roller surfaces with the lateral surface of a rolling body to be finish machined, set the rolling body in rotation about a rolling body axis, having a finishing tool which has an effective surface which can be adjusted along an adjustment axis in the direction of the lateral surface of the rolling body and can be pressed against the lateral surface, having an oscillation drive for driving the finishing tool along an oscillation axis.Such a device is known from EP 3 100 823 B1. It makes it possible to rotate rolling bodies with the aid of roller pairs and at the same time to transport them in a direction parallel to the axis of the rolling body. To produce a profile of the rolling bodies that is rounded at least at the edges, the roller surfaces have a complex profile with which the rolling bodies are transported along a wave-shaped transport axis and, as seen in the transport direction at the height of the finishing tools, are in each case raised further in the direction of the effective surfaces of the finishing tools than in a region between two finishing tools. This method is also known as a "continuous process" and has the disadvantage that longer workpieces require a correspondingly long transport path, in particular if a greater rounding of the profile with a correspondingly increased material removal of the rolling element is desired.From DE 195 43 941 C1 a device with the features of the preamble of claim 1 is known.The object of the present invention is to provide a simple and compact device which makes it possible to provide relatively long rolling bodies with a profiled outer surface.This object is achieved by a device having the features of claim 1.The device according to the invention makes it possible to provide relatively long rolling bodies with a profiled lateral surface without this being associated with the disadvantages known from a continuous process (long transport path, long device, low material removal).The profiling of the lateral surface is in particular a lateral surface profile which is logarithmic or "quasi-logarithmic", at least along a partial length of the profile of the rolling body. For example, in the case of cylindrical rolling bodies which are used for a cylindrical roller bearing, it is conceivable for a central region of the profile of the lateral surface to be straight and to delimit a cylindrical central region, which is adjoined in each case by a region of logarithmic tapering on both sides. The latter regions can merge into an edge rounded portion in the region of the lateral end faces of the rolling body.In a preferred embodiment of the invention, it is provided that the roller surfaces and the jacket surface have a profile which is complementary to one another. This means that, viewed at least along a partial length of the profile, the roller surfaces and the lateral surface bear against one another along a contact line (deviating from the prior art mentioned at the beginning, in which a workpiece is supported only at the height of a contact point along its profile of the lateral surface). For example, it is possible for the roller surfaces to have cylindrical or frustoconical regions which interact with the cylindrical or frustoconical lateral surface of a workpiece.A simple construction of the device results if the oscillation axis is oriented parallel to the transport axis. This is advantageous in particular when a plurality of finishing tools are arranged, as viewed along the transport axis, which finish partial regions of a workpiece that are offset with respect to one another and / or different workpieces.In particular in connection with the aforementioned alignment of the oscillation axis parallel to the transport axis, it is preferred if the two roller surfaces are inclined in the same direction with respect to the transport axis when viewed along the feed axis. In the case of a parallel alignment of the oscillation axis with respect to the transport axis, the inclination of the roller surfaces and the geometry of the lateral surface of the rolling body determine the angle between the oscillation axis and the rolling body axis. Such an angle can be at least 2°, for example. The angle can be, for example, at most approximately 30°.In a further preferred embodiment, it is provided that the roller body axis, as viewed along the feed axis of the finishing tool, is oriented parallel to the transport axis, which enables a particularly simple transport of the roller body.A further preferred embodiment of the invention provides that a rotational position of the finishing tool can be adjusted around the feed axis, in particular by means of a rotational position drive. This enables a particularly variable finish machining of also different workpieces and shell surface profiles.The device according to the invention enables a compact construction with which, for example, only one workpiece is machined in each case. Due to the compactness of the device, however, it is possible and advantageous to provide at least two pairs of rollers, as seen along the transport axis, with rollers driven rotatably about respective roller axes and / or for the rollers of at least one pair of rollers to have at least two roller surfaces, as seen along the transport axis. In this way, viewed along the transport axis, a plurality of mutually offset lateral surfaces of a workpiece can be machined simultaneously and / or a plurality of workpieces can be machined simultaneously.It is correspondingly advantageous if at least two finishing tools are provided distributed along the transport axis for finishing a rolling body or a section of a rolling body.To further simplify the structure of the device, it is proposed that the at least two finishing tools can be driven in an oscillating manner along mutually parallel oscillation axes by means of a common oscillation drive. These mutually parallel oscillation axes can also be aligned with one another, which is advantageous in particular when the oscillation axis is aligned in a direction parallel to the transport axis.It is furthermore preferred if the blocking device has at least one blocking element in the form of a stop. Preferably, this stop rotates together with a roller about its roller axis and is formed in particular integrally with the roller. This enables a low-wear rolling of an end face of the rolling body against the stop of the likewise rotating roller.Further features and advantages of the invention are the subject matter of the following description and the graphical representation of a preferred exemplary embodiment.The drawing shows FIG. 1 shows a perspective view of an embodiment of a device for finish machining rolling bodies; FIG. 2 is a plan view of an arrangement with a pair of rollers and a rolling element; FIG. 3 shows a front view of the rolling element and a roller of the arrangement according to FIG. 2 ; and FIG. 4 is a top view corresponding to FIG. 2, wherein a horizontally cut finishing tool is additionally shown.In the drawing, a device for finish machining rolling elements is denoted overall by the reference sign 10. The device 10 serves for finish machining of workpieces in the form of rolling bodies 12. the rolling bodies 12 are rotationally symmetrical with respect to a rolling body axis 14 and extend between a first end 16 and a second end 18, see FIGS. 2 to 4, as viewed along the rolling body axis 14.The rolling bodies 12 can be transported between an inlet 22 and an outlet 24 of the device 10, as seen along a transport axis 20, in particular using a lifting comb 26 which is known per se and therefore not described in any further detail.The apparatus 10 includes a first pair 28 of rollers; optionally, a second pair 30 of rollers is provided. The roller pair 28 has a first roller 32 and a second roller 34, which are driven rotatably about respective roller axes 36, 38 by means of a drive which is known per se and is therefore not illustrated.The rollers 32, 34 each have a circumferential surface 40, 42 which is, for example, frustoconical and which preferably each bear along a contact line 44, 46 against a circumferential surface 48 of the rolling bodies 12, cf. FIG. 3.The device 10 comprises at least one finishing tool 50, in particular in the form of a finishing stone. The finishing tool 50 has an effective surface 52 facing the lateral surface 48 of the rolling body 12. This effective surface can be adjusted along an adjustment axis 54 in the direction of the circumferential surface 48 of the rolling body 12 and pressed against the circumferential surface 48. For this purpose, a feed drive known per se and therefore not described in more detail is provided.The device 10 further comprises at least one rotary position drive 56, compare FIG. 1, by means of which a finishing stone 50 can be adjusted in its rotary position around the feed axis 54.In the apparatus 10 shown in the drawing, two finishing tools 50 are provided, which are associated with a pair 28 of rollers. The second pair of rollers 30 is likewise assigned two finishing tools 50 in a corresponding manner.The rotary position drives 56 of the finishing tools 50 are held on a holder 58, which extends substantially parallel to the transport axis 20.The holder 58 is held on an oscillation drive 60 which drives the holder 58 in an oscillating manner along an oscillation axis 62.In the exemplary embodiment shown, the oscillation axis 62 runs parallel to the transport axis 20, but it is possible to arrange the oscillation axis 62 inclined to the transport axis 20 as viewed along the feed axes 54 of the finishing tools 50, by providing a bearing at an angle to one another between the holder 58 and the oscillation drive 60, and furthermore to set the effective surfaces 52 of the finishing stones 52 parallel to such an inclined oscillation axis 62 by means of the rotary position drives 26.The apparatus 10 further comprises a blocking device 64, which in the simplest case is formed by a stop 66 of a roller 32 and / or 34 extending radially outwards with respect to a roller surface 42. The stop 66 serves for the contact of a partial section of an end face 18 of the rolling element 12, compare FIGS. 2 and 3. The stop 66 preferably extends completely around the roller axis 38 as viewed in the circumferential direction.In particular for the case of a mutually parallel alignment of the oscillation axis 62 and the transport axis 20, it is preferred if the roller surfaces 40, 42 are inclined in the same direction with respect to the transport axis 20 as viewed along the feed axis 54 (perpendicular to the plane of the drawing in FIG. 2 ). This inclination in the same direction makes it possible to incline the rolling body axis 14 by an angle 68 relative to the transport axis 20, as viewed along the feed axis 54. This angle 68 then corresponds, when the oscillation axis 62 is oriented parallel to the transport axis 20, to the angle between the oscillation axis 62 and the rolling body axis 14, as seen along the feed axis 54 (runs perpendicular to the plane of the drawing in FIG. 4 ).For finish machining of a rolling body 12, the lifting comb 26 is equipped with rolling bodies 12 and, as viewed along the transport axis 20, is introduced into the device 10 from the inlet 22. In this case, the rolling bodies 12 or their rolling body axles 14 are arranged above a horizontal plane spanned by the roller axles 36, 38. As soon as the rolling bodies 12 are arranged at the height of the roller surfaces 40, 42 as seen along the transport axis 20 and an end surface 18 of a rolling body 12 comes into contact with the stop 66 of a roller 34, the lifting comb 26 can be lowered downwards, so that a rolling body 12 is accommodated between the two roller surfaces 40 and 42 and is pressed against the stop 66 as seen along the transport axis 20.For finishing the outer surface 48 of the workpiece of the rolling body 12, the finishing tool 50 is lowered with its effective surface 52 from a spaced position in the direction of the outer surface 48 until the effective surface 52 comes into contact with the outer surface 48. The rollers 32, 34 are driven in the rotational direction, such that the rolling bodies 12 rotate about respective rolling body axes 14. By pressing the effective surface 52 against the lateral surface 48 and by simultaneous movement of the effective surface 52 in a direction parallel to the oscillation axis 62, a cross-ground structure characteristic for the finishing process is produced on the respective rotating lateral surfaces 48 of the rolling bodies 12.Due to the angular arrangement (as seen along the feed axis 54) of the oscillation axis 62 and the rolling element axis 14, the lateral surface 48 is provided with a rounded profile, for example a logarithmic profile.In a further embodiment, not shown in the drawing, it is possible to align the roller body axis 14 of a roller body 12 parallel to the transport axis 20, as seen along the feed axis 54. An angular arrangement between the oscillation axis 62 and the rolling body axis 14 can then be set by means of the rotary position drive 56.

Claims

Device (10) for finish machining of rolling bodies (12), having a pair (28) of rollers (32, 34) which are driven rotatably about respective roller axes (36, 38) and which, together by contact of their respective roller surfaces (40, 42) with the lateral surface (48) of a rolling body (12) to be finish machined, set the rolling body (12) in rotation about a rolling body axis (14), having a finishing tool (50) which has an effective surface (52) which can be adjusted in the direction of the lateral surface (48) of the rolling body (12) along an adjustment axis (54) and can be pressed against the lateral surface (48), having an oscillation drive (60) for driving the finishing tool (50) along an oscillation axis (62), wherein, as seen along the adjustment axis (54), the oscillation axis (62) and the rolling body axis (14) intersect one another and are arranged at an angle to one another, characterized in that, a blocking device (64) is provided which blocks a transport movement of the rotating rolling body (12) along a transport axis (20) parallel to the roller axes (36, 38) counter to a transport direction directed from an inlet (22) to an outlet (24) of the device (10).Device (10) according to claim 1, characterised in that the roller surfaces (40, 42) and the lateral surface (48) have a profile which is complementary to one another.Device (10) according to claim 1 or 2, characterised in that the oscillation axis (62) is oriented parallel to the transport axis (20).Device (10) according to one of the preceding claims, characterized in that the two roller surfaces (40, 42), as viewed along the feed axis (54), are inclined in the same direction with respect to the transport axis (20).Device (10) according to claim 1 or 2, characterised in that the rolling body axis (14), as seen along the feed axis (54) of the finishing tool (50), is oriented parallel to the transport axis (20).Device (10) according to one of the preceding claims, characterized in that a rotational position of the finishing tool (50) can be adjusted around the feed axis (54), in particular by means of a rotational position drive (56).Device (10) according to one of the preceding claims, characterized in that, as seen along the transport axis (20), at least two pairs (28, 30) with rollers (32, 34) driven rotatably about respective roller axes (36, 38) are provided and / or in that the rollers (32, 34) of at least one pair (28, 30) of rollers have at least two roller surfaces (40, 42), as seen along the transport axis (20).Device (10) according to one of the preceding claims, characterized in that at least two finishing tools (50) are provided for finishing a respective rolling body (12) or at least a portion of a rolling body (12), which finishing tools are arranged distributed along the transport axis (20).Device (10) according to claim 8, characterised in that the at least two finishing tools (50) can be driven in an oscillating manner along mutually parallel oscillation axes (62) by means of a common oscillation drive (60).Device (10) according to one of the preceding claims, characterized in that the blocking device (64) has at least one blocking element in the form of a stop (66) which is preferably rotatable together with a roller (34) about its roller axis (38) and is in particular formed integrally with the roller (34).

Images