WO2024188584A1

WO2024188584A1 - Geared motor

Info

Publication number: WO2024188584A1
Application number: PCT/EP2024/053915
Authority: WO
Inventors: Sven Wurzer; Stefan Hannet
Original assignee: Sew-Eurodrive Gmbh & Co. Kg
Priority date: 2023-03-14
Filing date: 2024-02-15
Publication date: 2024-09-19
Also published as: DE102024104310A1

Abstract

The invention relates to a geared motor, comprising: • - a shaft, • - an adapter shaft (1), • - a toothing part (42), wherein: the adapter shaft is hollow; the adapter shaft has a clamping region (5) and a connection region (6); the shaft is inserted in the connection region; the toothing part (42) has a running toothing and a pin axially adjacent to the running toothing or axially spaced apart from the running toothing, said pin having external toothing, in particular a knurl toothing; the pin is connected to the adapter shaft in an interlocking manner; the adapter shaft has a slot (8); the slot (8) extends in the circumferential direction over a circumferential angle which is between 90° and 270°; the slot is formed in an uninterrupted manner through the adapter shaft in the radial direction.

Description

Gear motor

Description:

The invention relates to a geared motor.

It is commonly known that a geared motor has a gearbox driven by an electric motor.

The closest state of the art is a geared motor known from JP 2014- 1 835 A.

From DE 100 03 923 A1 a method for connecting a hub to a shaft is known.

From DE 196 20 330 A1 a gear fastening on a shaft is known.

A radial clamping hub is known from DE 101 55 581 A1.

The invention is therefore based on the object of developing a geared motor, wherein the geared motor should be designed to be compact.

According to the invention, the object is achieved in the geared motor according to the features specified in claim 1.

Important features of the invention in the geared motor are that the geared motor has a shaft, in particular a rotor shaft, an adapter shaft, a toothed part, in particular a sun gear, wherein the adapter shaft is hollow, wherein the adapter shaft has a clamping area and a connecting area, wherein the shaft is inserted into the clamping area, in particular protrudes through the clamping area, and is non-positively connected to the clamping area, wherein the toothed part has a running toothing, in particular an involute toothing, and a pin which is axially adjacent to the running toothing or axially spaced from the running toothing and which has an external toothing, in particular a knurled toothing, wherein the pin is positively connected to the adapter shaft, in particular in that the external toothing is cut into the adapter shaft, wherein the adapter shaft has a slot, wherein the slot extends in the circumferential direction over a circumferential angle whose amount is between 90° and 270°, wherein the slot is formed continuously through the adapter shaft in the radial direction, in particular wherein the radial direction is related to the axis of rotation of the shaft and the circumferential direction is also related to the axis of rotation of the shaft.

The advantage here is that the slot separates the clamping area from the connection area, thus facilitating elastic deformation of the clamping area. In addition, the normal direction of the slot plane of the slot is aligned parallel to the axial direction. This means that the shaft extends through the clamping area into the connection area. In the connection area, the adapter shaft can be centered to the shaft and in the clamping area a force-fit connection is made to transmit the torque of the shaft to the adapter shaft, which then transmits this torque to the sun gear via the pin of the sun gear. The advantage of the invention is a compact design in that the force-locking connection on the adapter shaft is formed as one piece. This is because the clamping area of the adapter shaft is formed as one piece with the connection area. This means that no separate clamping ring is necessary.

In addition, the gear motor can be designed compactly because the sun gear of the planetary gear is directly inserted into the adapter shaft, into which the rotor shaft of the electric motor is also inserted as a shaft. The rotation axis of the sun gear and the rotor shaft are thus aligned coaxially with each other. In particular, the shaft and the rotor shaft are only slightly axially spaced from each other, so that the gear motor can be designed compactly.

In an advantageous embodiment, the slot is arranged axially between the clamping area and the connection area. The advantage here is that the elasticity of the clamping area is improved and the adapter shaft can still be made in one piece.

In an advantageous embodiment, the adapter shaft has a stepped bore which has a first region in the axial direction in front of the step of the stepped bore and a second region in the axial direction behind the step, wherein the pin of the sun gear is accommodated in the second region, in particular wherein the clear inner diameter of the first region is larger than the clear inner diameter of the second region, wherein the shaft projects into the first region. It is advantageous that the pin is axially spaced from the shaft.

In an advantageous embodiment, the running gear of the sun gear is axially spaced from the area covered by the journal in the axial direction, in particular, the running gear is in engagement with the respective gearing of planetary gears, which are arranged rotatably mounted in a planet carrier acting as an output shaft and are in engagement with a ring gear connected in a rotationally fixed manner to the housing part of the transmission. The advantage here is that the sun gear with its Pin can be connected to the adapter shaft and transmits the torque to the planetary gears with its running gear.

In an advantageous embodiment, the inner ring of a bearing is placed on the adapter shaft, the outer ring of which is accommodated in an adapter housing of the gear motor, in particular where the bearing is a roller bearing. The advantage here is that the adapter shaft is rotatably mounted by means of the bearing and thus the sun gear is mounted via the adapter shaft, which is also supported by means of the shaft.

In particular, the positive connection area between the journal and the adapter shaft covered an axial area that overlaps with or is contained in the area covered by the bearing in the axial direction. The advantage here is that the journal can be supported more robustly via the adapter shaft.

In an advantageous embodiment, the area covered by the pin or its external toothing in the axial direction is encompassed by the area covered by the second area in the axial direction. The advantage here is that the pin is received in the adapter shaft in a form-fitting manner. The external toothing of the pin is preferably cut into the adapter shaft and is thus connected very rigidly. In addition, a high torque can be transmitted.

In an advantageous embodiment, the area covered by the bearing in the axial direction overlaps with the area covered by the second area in the axial direction. The advantage here is that the pin is accommodated in the second area and the bearing is also attached in the same axial area. High forces can therefore be introduced into this corresponding axial area of the adapter shaft, for which purpose the adapter shaft also has an increased wall thickness.

In an advantageous embodiment, the axial position of the step of the stepped bore is included in the area covered by the bearing in the axial direction. The advantage here is that the step does generate a notch effect, but the bearing reinforces the adapter shaft in the corresponding axial area. In an advantageous embodiment, the radial wall thickness of the adapter shaft in the area covered by the second area in the axial direction is greater than the radial wall thickness of the adapter shaft in the area of the adapter shaft adjacent to the second area. The advantage here is that forces can be introduced into the thickened section of the connection area from the sun gear on the one hand and from the bearing on the other.

In an advantageous embodiment, the radial wall thickness of the adapter shaft in the area covered by the second area in the axial direction is greater than the radial wall thickness in the remaining section of the connection area. The advantage here is that forces can be introduced into the thickened section of the connection area from the sun gear on the one hand and from the bearing on the other.

In an advantageous embodiment, the axial width of the slot is at least five times smaller than the clear inner diameter of the first region and/or the outer diameter of the shaft in the region covered by the clamping region in the axial direction. The advantage here is that the slot is narrow and the gear motor can therefore be designed to be compact.

In an advantageous embodiment, three axially directed bores, in particular blind holes, are introduced into the clamping area, in particular wherein the bore axis of each of the three bores is aligned parallel to the axis of rotation of the shaft, in particular wherein the three bores are each designed as blind holes introduced from the axial end face of the clamping area and in particular all three are arranged at the same radial distance, in particular wherein the middle of the three bores in the circumferential direction has a smaller distance, in particular circumferential angular distance, from a second of the three bores than from the third of the three bores, in particular wherein one of the three bores functions as a balance of the radially directed semi-continuous slot. The advantage here is that balancing of the slot and the axial slot is made possible in a simple manner. In an advantageous embodiment, the clamping area has an axial slot that runs through the clamping area in the axial direction and in the radial direction, through which a clamping screw protrudes. The advantage here is that the clamping area can be shrunk onto the shaft to create the force-locking connection.

In an advantageous embodiment, the screw head of the clamping screw rests on a step of the clamping area, which is arranged in the clamping area on the first side of the axial slot, wherein on the other side, in particular the second side, of the axial slot the clamping area has a threaded area through which the clamping screw protrudes and into which the clamping screw is screwed. The advantage here is that the function of a clamping ring is integrated into the adapter shaft.

In an advantageous embodiment, a limiting element, in particular a bolt, is fastened in the clamping area and protrudes from the clamping area, wherein the limiting element limits the screw head in the screw axis direction and/or the limiting element rests on the side of the screw head facing away from the threaded area, in particular for spreading the axial slot, wherein the clamping screw, in particular on the side of the threaded area facing away from the screw head of the clamping screw and/or in the area of the clamping screw protruding from the clamping area, in particular facing away from the axial slot, has an annular groove in which a locking ring is arranged in a form-fitting manner, in particular snapped in, in particular for limiting the spreading of the axial slot. The advantage here is that it is possible to spread the axial slot and a spreading limit is provided to protect the adapter shaft.

In an advantageous embodiment, the axial slot opens into the slot, wherein the circumferential angle range covered by the axial slot in the circumferential direction is contained in the circumferential angle range covered by the slot in the circumferential direction, in particular, wherein the axial slot covered in the circumferential direction

Circumferential angle range in the circumferential direction is spaced on both sides from the ends of the

Slot in the circumferential direction covered circumferential angle range, in particular where the slot plane of the axial slot is aligned perpendicular to the slot plane of the slot. The advantage here is that the clamping area of the adapter shaft is designed to be sufficiently elastic. In addition, failure of the adapter shaft is prevented because the axial slot does not open into the slot at the end of the slot, but at a distance in the circumferential direction, thus reducing the notch effect in the area around the opening area.

In an advantageous embodiment, the area covered by the shaft in the axial direction overlaps with the area covered by the bearing in the axial direction, in particular the shaft is accommodated in the first area, in particular in the area covered by the bearing in the axial direction, with a precise fit and/or without play. The advantage here is that the shaft supports the adapter shaft from the radial inside and thus stiffens the bearing receiving area of the adapter shaft, which also surrounds the pin of the sun gear.

In an advantageous embodiment, the pin is axially spaced from the first area. The advantage here is that the sun gear does not protrude into the first area of the blind hole, in particular the further area of the blind hole, and thus leaves the shaft enough space to protrude as close as possible to the bearing in the axial direction and thus stabilize and stiffen the adapter shaft from the inside.

Further advantages arise from the subclaims. The invention is not limited to the combination of features in the claims. The person skilled in the art will recognize further useful combination options of claims and/or individual claim features and/or features of the description and/or the figures, in particular from the task and/or the task arising from a comparison with the prior art. The invention will now be explained in more detail using schematic illustrations:

Figure 1 shows an adapter shaft 1 of a gear motor according to the invention in an oblique view.

Figure 2 shows a cross-section of the adapter shaft 1.

Figure 3 shows a side view of the adapter shaft 1.

Figure 4 shows a section of the planetary gear.

Figure 5 shows a top view of the cutaway planetary gear.

Figure 6 shows a further oblique view of the adapter shaft 1 from a first viewing direction, so that an oblique groove 60 introduced into the clamping area 5 is visible.

Figure 7 shows a further oblique view of the adapter shaft 1 from a second viewing direction, so that an oblique groove 60 introduced into the clamping area 5 is visible.

Figure 8 shows a cutting plane A-A which cuts through the half-slot 8.

Figure 9 shows a cross section through the adapter shaft 1, wherein the cutting plane of the cross section marked according to Figure 8 bisects a half slot 8 of the adapter shaft 1.

As shown in the figures, the adapter shaft 1 has a clamping area 5 which is separated from a connection area 6 by means of the half-slot 8, i.e. a radially directed semi-continuous slot. The normal of the slot plane of the half-slot 8 is aligned parallel to the axial direction, in particular parallel to the axis of rotation of the adapter shaft 1. The adapter shaft 1, together with its annular clamping region 5 and its bush-shaped connecting region 6, is formed in one piece, in particular in one part.

A shaft, in particular the rotor shaft of an electric motor of the gear motor, can be inserted into the clamping area 5 and connected in a force-locking manner by actuating a clamping screw 2.

The pin section of a sun gear of a planetary gear of the geared motor, which is in particular toothed with a knurled toothing, can be inserted into the connection area 6 and thus connected in a form-fitting manner. In this way, the adapter shaft 1 can be used as a coupling between the driving rotor shaft and the sun gear 42.

The clamping area has an axial slot which extends through the clamping area 5 in the axial direction and in the radial direction and through which the clamping screw 2 protrudes.

The screw head of the clamping screw 2 rests on a step which is arranged in the clamping area 5 on the first side of the axial slot.

On the other side of the axial slot, the clamping area has a threaded area through which the clamping screw 2 protrudes and into which the clamping screw 2 is screwed.

In the area of the clamping screw 2 protruding from the threaded area, a locking ring 4 is arranged, which is snapped into an annular groove of the clamping screw 2 and thus acts as a spreading limiter.

This is because a bolt 3, which is inserted into a hole in the clamping area, the hole axis of which is aligned perpendicular to the screw axis of the clamping screw 2, serves to limit the screw head of the clamping screw 2. This prevents the screw head from moving out of the bolt 3 when the clamping screw 2 is unscrewed from the threaded area, and thus the axial slot is widened until the locking ring 4 rests against the clamping area and prevents further expansion. This prevents the clamping area from being destroyed. The screw head of the clamping screw 2 preferably has a hexagon socket so that the clamping screw 2 can be easily operated using an external hexagon tool.

In addition, three axially directed bores 20 are provided in the clamping area, which are intended for balancing the adapter shaft 1.

The three bores 20 are each designed as blind holes introduced from the axial front side of the clamping area and preferably all three are arranged at the same radial distance.

The middle of the three bores 20 in the circumferential direction has a smaller distance, in particular circumferential angular distance, from a second of the three bores 20 than from the third of the three bores 20.

By selecting the number of three holes 20, one of the three holes can be provided for balancing the radially directed semi-through slot.

The axial direction is always parallel to the axis of rotation of the shaft and/or the sun gear 42. The radial direction, the respective radial distance and the circumferential direction are also each related to the axis of rotation of the shaft and/or the sun gear 42.

The screw axis of the clamping screw 2 is aligned perpendicular to the axis of rotation of the shaft and/or the sun gear 42. In addition, the bore axis of the bore receiving the bolt 3 is also aligned perpendicular to the axis of rotation of the shaft and/or the sun gear 42.

As shown in Figures 4 and 5, the gear of the geared motor has a housing part 44 which is connected to an adapter housing 40 to which a bearing flange of the electric motor of the geared motor can be connected, wherein the bearing flange is connected to a stator housing of the electric motor. A bearing of the rotor shaft of the electric motor is accommodated in the bearing flange, whereby the rotor shaft can be inserted into the hollow area of the clamping area and can be connected in a force-fitting manner by actuating the clamping screw 2.

For this purpose, the adapter shaft 1 is hollow and has an axially continuous blind hole. To accommodate the rotor shaft, the blind hole has a first axial area arranged axially in front of a step of the blind hole. The clear diameter of the first axial area of the blind hole is larger than the clear diameter of the second area arranged axially behind the step of the blind hole.

The sun gear 42 is inserted with its externally toothed pin into the second area of the adapter shaft, wherein the external toothing of the pin is cut into the material of the adapter shaft, in particular in the second area.

A bearing 41 is pushed onto the adapter shaft 1 and is accommodated in the adapter housing 40. In particular, the bearing 41 is positioned against a step on the outer surface of the adapter shaft 1.

The area covered by the bearing 41 in the axial direction comprises the area covered by the second area in the axial direction and/or the area covered by the pin of the sun gear 42 in the axial direction.

The area covered by the bearing 41 in the axial direction overlaps with the area covered by the first area in the axial direction.

The area covered by the first area in the axial direction comprises the area covered by the clamping area 5 in the axial direction and overlaps with the area covered by the connecting area 6 in the axial direction.

The rotor shaft projects axially into the first region to such a depth that the region covered by the rotor shaft in the axial direction includes the region covered by the semi-continuous slot in the axial direction and the region covered by the clamping region 5 in the axial direction. The running gear of the sun gear 42, which is axially spaced from the pin area, is in engagement with the gears of planetary gears, which are also in engagement with the internal gear of a ring gear that is connected in a rotationally fixed manner to the housing part 44. The planetary gears are rotatably mounted on a planet carrier, which itself is rotatably mounted to the housing part 22 and functions as the output shaft 43 of the planetary gear of the geared motor.

In the axial direction, the holes 20 are spaced apart from the second region. Accordingly, the clamping region 5 is also spaced apart from the second region in the axial direction.

It is important in the invention that the step of the stepped bore is arranged in the area covered by the bearing in the axial direction. In this way, a greater wall thickness can be achieved in the area covered by the first area in the axial direction than in the remaining connection area 6. The sun gear 42 and the bearing can thus be accommodated in a very rigid area of the adapter shaft 1. This area of the bearing mount and the mount of the sun gear 42 is therefore very rigid, whereas the transition to the clamping area is more elastic, particularly due to the semi-continuous slot.

The semi-continuous slot extends by 180° in the circumferential direction and passes completely through the hollow adapter shaft 1 in the radial direction. Preferably, the axial width of the semi-continuous slot differs from the slot width of the axial slot by a maximum of 50%.

As shown in Figure 6, the oblique groove 60 arranged diametrically to the axial slot of the clamping area 5 narrows the clamping area 5 and thus increases its elasticity. In particular, the oblique groove 60 cuts through an edge of the clamping area 5 and is arranged in the circumferential direction between two of the holes 20. The oblique groove 60 can advantageously contribute to the balancing of the adapter shaft 1 depending on the dimensioning, i.e. groove depth, especially since it is not axially continuous. As shown in Figure 9, the half-slot 8 has at its first end in the circumferential direction a first slot end 91 which is designed to be straight, and at its other end a second slot end 90 which is designed to be straight, in particular not curved.

The first slot end 91 and the second slot end 90 are therefore designed to be purely radially directed. As the radial distance increases, the second slot end 90 always has the same constant circumferential angular position.

In a further embodiment, however, only the second slot end 90 is designed to be straight as shown in Figure 9. The first slot end 91, on the other hand, is designed to be curved.

The first slot end 91 has a circumferential angle that increases monotonically, in particular strictly monotonically, with increasing radial distance. Thus, the circumferential angle range covered by the half slot 8 increases monotonically, in particular strictly monotonically, with increasing radial distance. In this way, the adapter shaft 1 has a higher load capacity, in particular higher forces can be transmitted.

Since the adapter shaft 1 is hollow, the half-slot 8 is limited by the front slot end (90, 91) in the circumferential direction and the rear slot end (90, 91) arranged at the other end of the half-slot 8.

However, it is also important that the oblique groove 60 is not axially continuous but that the area covered by the oblique groove 60 in the axial direction is shorter than the area covered by the clamping area 5 in the axial direction, which includes the area covered by the oblique groove 60 in the axial direction.

In further embodiments according to the invention, the step of the stepped bore is arranged axially centrally in the area covered by the bearing 41 in the axial direction. This achieves increased stability. List of reference symbols

1 adapter shaft

2 clamping screw

3 bolts

4 Retaining ring

5 Clamping range

6 Connection area

7 Axial slot

8 Half slot

20 Bore

40 adapter housing

41 warehouses

42 Sun gear

43 output shaft, planet carrier

44 Housing part

60 bevel groove

90 second slot end

91 first slot end

Claims

Patent claims:

1. Geared motor, comprising a shaft, in particular a rotor shaft, an adapter shaft, a toothed part, in particular a sun gear, the adapter shaft being hollow, the adapter shaft having a clamping region and a connecting region, the shaft being inserted into the clamping region, in particular protruding through the clamping region, and being connected to the clamping region in a force-locking manner, the toothed part having a running toothing, in particular an involute toothing, and a pin axially adjacent to the running toothing or axially spaced from the running toothing, which has an external toothing, in particular a knurled toothing, characterized in that the pin is positively connected to the adapter shaft, in particular in that the external toothing is cut into the adapter shaft, the adapter shaft having a slot, the slot extending in the circumferential direction over a circumferential angle, the amount of which is between 90° and 270°, the slot being formed continuously through the adapter shaft in the radial direction, in particular the radial direction being directed towards the axis of rotation of the shaft and the circumferential direction is also related to the axis of rotation of the shaft.

2. Geared motor according to claim 1, characterized in that the slot is arranged axially between the clamping region and the connecting region.

3. Geared motor according to one of the preceding claims, characterized in that the adapter shaft has a stepped bore which has a first region in the axial direction in front of the step of the stepped bore and a second region in the axial direction behind the step, wherein the pin of the sun gear is received in the second region, in particular wherein the clear inner diameter of the first region is larger than the clear inner diameter of the second region, wherein the shaft projects into the first region.

4. Geared motor according to one of the preceding claims, characterized in that the running teeth of the sun gear are axially spaced from the area covered by the pin in the axial direction, in particular wherein the running teeth are in engagement with the respective teeth of planetary gears which are rotatably mounted in a planet carrier acting as an output shaft and are in engagement with a ring gear connected in a rotationally fixed manner to the housing part of the gear.

5. Geared motor according to one of the preceding claims, characterized in that the inner ring of a bearing is placed on the adapter shaft, the outer ring of which is accommodated in an adapter housing of the geared motor, in particular wherein the bearing is a rolling bearing, in particular wherein the positive connection region between the pin and the adapter shaft covers an axial region which overlaps with the region covered by the bearing in the axial direction or is contained in it.

6. Geared motor according to one of the preceding claims, characterized in that the region covered by the pin or its external toothing in the axial direction is encompassed by the region covered by the second region in the axial direction.

7. Geared motor according to one of the preceding claims, characterized in that the region covered by the bearing in the axial direction overlaps with the region covered by the second region in the axial direction and/or that the axial position of the step of the stepped bore is included in the region covered by the bearing in the axial direction.

8. Geared motor according to one of the preceding claims, characterized in that the radial wall thickness of the adapter shaft in the region covered by the second region in the axial direction is greater than the radial wall thickness of the adapter shaft in the region of the adapter shaft adjacent to the second region, and/or that the radial wall thickness of the adapter shaft in the region covered by the second region in the axial direction is greater than the radial wall thickness in the remaining section of the connection region.

9. Geared motor according to one of the preceding claims, characterized in that the axial width of the slot is at least five times smaller than the clear inner diameter of the first region and/or the outer diameter of the shaft in the region covered by the clamping region in the axial direction.

10. Geared motor according to one of the preceding claims, characterized in that three axially directed bores, in particular blind holes, are introduced into the clamping area, in particular wherein the bore axis of each of the three bores is aligned parallel to the axis of rotation of the shaft, in particular wherein the three bores are each designed as blind holes introduced from the axial end face of the clamping area and in particular all three are arranged at the same radial distance, in particular wherein the middle one of the three bores in the circumferential direction has a smaller distance, in particular circumferential angular distance, from a second of the three bores than from the third of the three bores, in particular wherein one of the three bores functions as a balance for the radially directed semi-continuous slot.

11. Geared motor according to one of the preceding claims, characterized in that the clamping area has an axial slot which passes through the clamping area in the axial direction and in the radial direction and through which a clamping screw protrudes, and/or that the screw head of the clamping screw rests on a step of the clamping area which is arranged in the clamping area on the first side of the axial slot, wherein on the other side, in particular the second side, of the axial slot the clamping area has a threaded area through which the clamping screw protrudes and into which the clamping screw is screwed.

12. Geared motor according to one of the preceding claims, characterized in that a limiting element, in particular a bolt, is fastened in the clamping area and protrudes from the clamping area, wherein the limiting element limits the screw head in the screw axis direction and/or the limiting element rests on the side of the screw head facing away from the threaded area, in particular for spreading the axial slot, wherein the clamping screw, in particular on the side of the threaded area facing away from the screw head of the clamping screw and/or in the area of the clamping screw protruding from the clamping area, in particular facing away from the axial slot, has an annular groove in which a locking ring is arranged in a form-fitting manner, in particular snapped in, in particular for limiting the spreading of the axial slot.

13. Geared motor according to one of the preceding claims, characterized in that the axial slot opens into the slot, wherein the circumferential angle range covered by the axial slot in the circumferential direction is contained in the circumferential angle range covered by the slot in the circumferential direction, in particular wherein the circumferential angle range covered by the axial slot in the circumferential direction is spaced apart on both sides in the circumferential direction from the ends of the circumferential angle range covered by the slot in the circumferential direction, in particular wherein the slot plane of the axial slot is aligned perpendicular to the slot plane of the slot.

14. Geared motor according to one of the preceding claims, characterized in that an oblique groove is arranged in the clamping area, in particular diametrically opposite the axial slot, in particular thus spaced 180° from the axial slot in the circumferential direction, in particular wherein the area covered by the oblique groove in the axial direction is contained in the area covered by the clamping area in the axial direction.

15. Geared motor according to one of the preceding claims, characterized in that the half-slot (8) has a first slot end (91) at its first end in the circumferential direction, which is designed to be straight in the radial direction, and a second slot end (90) at its other end, which is designed to be curved, in particular so that the second slot end (90) has a circumferential angular position that increases monotonically, in particular strictly monotonically, with increasing radial distance and the first slot end (91) has a circumferential angular position that is constant with increasing radial distance, and/or that the area covered by the shaft in the axial direction overlaps with the area covered by the bearing in the axial direction, in particular wherein the shaft is received in the first area, in particular in the area covered by the bearing in the axial direction, with a precise fit and/or without play, and/or that the pin is axially spaced from the first area.