CN219549415U - Ball-type synchronous universal joint and shaft assembly - Google Patents

Abstract

The present utility model relates to a ball-type synchronous universal joint and a shaft assembly, the ball-type synchronous universal joint having at least a joint outer member. In at least one cross section of the outer joint part extending transversely to the axis of rotation, at least one sub-region of each support surface extends along a diameter at a common nominal dimension; wherein each of the sub-regions extends across at least three segments along the circumferential direction; wherein the second section is arranged between the first section and the third section along the circumferential direction; wherein a narrow tolerance is specified for the second section and a larger tolerance is specified for the first section and the third section, respectively, relative to the nominal size.

Description

Ball-type synchronous universal joint and shaft assembly

Technical Field

The present utility model is directed to a ball and socket joint (kugelgliichlaufgelenk). The present ball-and-socket synchronous joint (hereinafter also referred to as joint) is used in the case of motor vehicles, in particular in side shaft assemblies or longitudinal shaft assemblies. In addition to this, the ball-type synchro-gimbal can be used in all other applications where ball-type synchro-gimbal has been used so far. Preferably, the ball-type synchro-joint is a ball-type synchro-motion joint (kugeleichlaufverskiebegengel).

Background

In particular in the case of motor vehicles, ball-type synchronous (displacement) universal joints are used in the region of the longitudinal shaft assembly, but also in the sideshaft assembly. The longitudinal shaft is used to transfer drive from the transmission to an axle (Achse). In particular, the transmission is arranged in a front region of the motor vehicle, and a longitudinal shaft assembly extending along a longitudinal axis of the motor vehicle is used to transmit drive force from the transmission to the rear axle. In the case of a longitudinal shaft assembly, a smaller bending angle of the universal joint is generally required, in particular 0 to 10 degrees. The sideshafts serve to transmit the drive force from the transmission or differential to the wheels, i.e. essentially parallel to the axles of the motor vehicle. The side shaft extends transversely to the longitudinal axis of the motor vehicle. In the case of a sideshaft, a large bending angle of the ball-type synchronous displacement joint is generally required, in particular an angle of 0 to 32, preferably 3 to 20.

The ball-type synchronous universal joint of the type considered here comprises a joint outer part having a rotational axis and an outer ball track (ball track of the ball-type synchronous mobile universal joint located on the outside) and a joint inner part having an inner ball track (ball track of the ball-type synchronous mobile universal joint located on the inside) and a plurality of torque-transmitting balls which are guided in the outer ball track and the inner ball track assigned to one another, respectively, and a cage which is provided with a plurality of cage windows which each receive one or more balls of the balls.

At least a portion of the outer ball track and at least a portion of the inner ball track may have a track tilt angle (of arbitrary orientation) with respect to the rotational axis.

If the ball-type synchronous joint is in a stretched position or arrangement (i.e. the joint inner part is not bent relative to the joint outer part), a movement of the joint inner part relative to the joint outer part along a common rotational axis is possible in the case of a ball-type synchronous moving joint, such that said rotational axes remain coaxially arranged to each other.

In the case of a ball-and-socket synchronous displacement joint, the joint inner part can be displaced by a total displacement distance along the rotational axis relative to the joint outer part.

In particular, the ball track bottoms of each ball track (i.e. the regions of the ball track which are arranged with maximum spacing from the rotational axis in the case of the outer ball track, respectively; the regions of the ball track which are arranged with minimum spacing from the rotational axis of the joint inner part in the case of the inner ball track), respectively, have a constant spacing in the radial direction relative to the rotational axis along the displacement path.

However, the following embodiments of ball-and-socket synchronous motion universal joints are also known: in this embodiment, the ball track bottom does not have a constant spacing from the axis of rotation. In this case, the distance from the axis of rotation is identical, in particular (only) for ball tracks lying opposite one another, but is not constant here over the displacement path or along the ball tracks.

The balls in the ball tracks perform track-guided movements (e.g., rolling, sliding, etc.) as the inner joint part of the ball synchronous motion joint moves relative to the outer joint part. The distance of movement of the cage is here ideally half the travel distance of the inner joint part relative to the outer joint part. In particular in the case of ball-type synchronous displacement universal joints, this displacement travel is limited by the physical stop of the inner part of the universal joint (ball hub) on the cage (ball cage) by contact of the parts of the universal joint.

In the case of the arrangement of a ball-type synchronous joint for the operation of the ball-type synchronous joint, the components of the joint are arranged in a defined arrangement relative to one another. In this arrangement of the components, the balls are arranged in defined areas of the ball tracks. That is, the arrangement does not include an assembled state or a service state in which the universal joints are bent or pulled apart or pushed together in a particular manner, for example in terms of assembly or accessibility.

When bending the inner joint part of the ball and socket synchronous joint, the inner joint part is pivoted from a stretched position (the rotational axis of the outer joint part and the rotational axis of the inner joint part being arranged coaxially to each other) into an (deflected) bent position. The rotational axis of the outer joint part and the rotational axis of the inner joint part then form a bending angle (not equal to "0").

Friction occurs between the outer joint part and the inner joint part or the cage when bending the ball joint and when the outer joint part moves relative to the inner joint part in the case of a ball joint. This friction occurs in particular on the support surfaces, for example between the outer ball tracks on the outer joint part, on which the inner joint part or the cage is supported with respect to the radial direction. Due to the provided contact of the joint outer part and the joint inner part or the cage, etc., these contact surfaces are very accurate, i.e. narrow tolerances are provided for these contact surfaces, so that a high cost is thereby incurred in the production of the ball-and-socket joint.

In this case, there is also a need to take into account increasingly stringent environmental requirements in the manufacture of motor vehicles, which require an increasingly better efficiency in the drive train sector. In ball-type synchronous joints, there is always a sliding movement in the cage track or on the support surface, while there is mainly a rolling movement in the ball track. Since the losses caused by rolling movements are generally much smaller than those caused by sliding friction, it is expedient in particular to improve the sliding friction surface in the case of measures for increasing the efficiency. Due to warpage when heat treating the ball-and-socket joint, it may occur: at the contact point of the cage with the outer part of the joint or at the contact point of the cage with the inner part of the joint, there is no longer a defined contact behavior, for which, for example, edge loading (Kantenbelastungen) may occur, as a result of which the grease film is scraped off and thus the friction value is increased during the movement of the parts of the ball-and-socket joint.

In particular in the field of mass production of motor vehicles, the requirements for all components increase in terms of installation space, weight and/or costs to be achieved. Thus, there is a long-felt need for: this type of joint has also been developed further in respect of the requirements mentioned.

Disclosure of Invention

The object of the present utility model is to solve at least partially the problems described in connection with the prior art. In particular, a ball-type synchronous joint should be provided which has as little friction as possible during operation, wherein, however, the production costs are reduced at the same time.

This is achieved by means of the ball-type synchronous joint according to the utility model. Further advantageous configurations of the utility model are given in the dependent claims. The features specified individually in the claims can be combined with one another in any technically meaningful way and can be supplemented by the facts explained in the description, wherein further embodiment variants of the utility model are disclosed.

A ball-type synchronous joint is advantageous in this respect, which has at least a joint outer part, a joint inner part or additionally a cage, which has a rotational axis and has an outer ball track, and which has an inner ball track and a plurality of torque-transmitting balls, which are guided in the outer ball track and the inner ball track assigned to one another, respectively, the cage being provided with a plurality of cage windows, which each receive one or more of the balls; wherein the outer ball tracks are arranged on the inner circumferential surface of the outer part of the universal joint and are arranged here in a distributed manner along the circumferential direction and extend at least in an axial direction parallel to the rotational axis; wherein a support surface for contacting the inner part of the joint or the cage is arranged between the two outer ball tracks; wherein, in at least one cross section of the outer part of the joint, which cross section extends transversely to the axis of rotation, at least one sub-region of each support surface extends along the diameter with a common nominal dimension; wherein each sub-region extends in a circumferential direction across at least three sections; wherein the second section is arranged between the first section and the third section along the circumferential direction; wherein a narrow tolerance is specified for the second section and a larger tolerance is specified for the first section and the third section, respectively, relative to the nominal size.

In particular, in cross section, the second section extends in a circumferential direction over a first angular range, wherein the first section and the third section each extend over a second angular range, which is smaller than the first angular range.

In particular, in the cross section, the maximum dimensional deviation from the nominal size is defined by corresponding tolerances; wherein the maximum dimensional deviation in the first section and the third section is at least twice the maximum dimensional deviation in the second section.

In particular, the tolerance only allows for dimensional deviations greater than the nominal dimensions.

In particular, in cross section, the transition between the support surface and the ball track is defined by a radius or a radius.

In particular, a modification of the segments of the support surface (cage rail) or of the prescribed tolerances of the segments is proposed such that the individual segments are no longer part of a cylindrical surface, but rather are designed such that they only contact the contact surfaces of the other parts of the joint in the second middle section, which surfaces are provided for contact. In this way, a defined contact is achieved even in the case of warping, avoiding edge supportAnd fresh lubrication material is brought into the contact site by the grease wedge as the parts of the universal joint move. For this purpose, the segments or sections of the cage rail do not have to have a convex shape as shown, but a radius greater than half the diameter of the cage rail or a shape similar thereto is also sufficient. In particular, only the tolerances can be adjusted in such a way that the desired geometry is preferably achieved.

In particular, the outer part of the joint is a forging; in this case, at least the support surface arranged in the cross section is formed exclusively by forging, i.e. in particular without mechanical post-processing.

In particular, the ball-type synchronous joint is a ball-type synchronous displacement joint, wherein the total displacement distance of the joint inner part relative to the joint outer part is at least 5 mm and preferably at most 100 mm, preferably at least 8 mm and at most 80 mm, particularly preferably at most 50 mm or at most 30 mm.

The total travel distance is in particular a part of the following ball path: during the set running of the ball-type synchronous mobile joint, the ball can/should be arranged in the ball track. In this case, the total displacement path does not include, in particular, the so-called end region of the ball track, in which functional limitations of the ball-type synchronous displacement universal joint already exist when the ball is arranged there. The travel range that can be achieved depends on the track inclination angle and the diameter of the ball.

According to a particularly advantageous configuration of the ball-and-socket joint, at least a part of the outer ball track and at least a part of the inner ball track can have a track inclination angle (of arbitrary orientation) with respect to the rotational axis. This means that the ball moves along the ball track not only in the axial direction (parallel) along the rotation axis, but also (transversely thereto) in the circumferential direction. Such a track inclination angle supports the control performance of the joint with respect to the ball, so that the position of the ball in the axial direction is determined at any point in time when the ball-type synchronous movement joint is running. In particular, at least one track pair is implemented, which comprises an outer ball track and an inner ball track, which have balls arranged between them and have track inclination angles of different orientations, such that the outer ball track intersects the inner ball track.

In particular, the cross section is arranged in an axial section of the outer part of the joint, in which axial section the balls are arranged in operation provided for the ball-type synchronous joint.

In particular, the ball-type synchronous universal joint has at least four balls. Ball-type synchronous universal joints have at least 6 or 6+n (n=1, 2,3, …) balls.

The foregoing description is directed to the basic construction and/or function of a ball-and-socket joint.

A shaft assembly is further proposed, comprising at least the described ball-and-socket joint and a first shaft connected to an outer part of the joint and a second shaft connected to an inner part of the joint.

A motor vehicle is also proposed, which has at least one ball-type synchronous universal joint proposed here. In particular, the ball-type synchronous universal joint is proposed for use in passenger vehicles.

As a precautionary measure, the ordinal terms ("first", "second" …) used herein are used primarily (only) to distinguish between a plurality of items, parameters or processes of the same type, i.e. in particular without necessarily predefining the relevance and/or order of these items, parameters or processes to each other. If correlation and/or order is desired, this is explicitly described herein or will be apparent to those skilled in the art upon studying the specifically described configuration.

Drawings

The utility model and the technical field are described in detail below with the aid of the figures. It should be noted that the present utility model should not be limited by the illustrated embodiments. In particular, it is also possible to extract some aspects of the facts explained in the figures and to combine them with other components and recognitions from the description and/or the figures, as long as they are not explicitly described. Like reference numerals designate like items so that the description from other figures can be considered as supplementary if necessary. The drawings schematically show:

fig. 1: the ball-type synchronous universal joint is shown in section in a view along the axis of rotation;

fig. 2: the outer part of the ball-and-socket joint according to fig. 1 is shown in section in a view along the axis of rotation and in a side view in section;

fig. 3: details Z of the outer part of the joint according to fig. 2 are shown in section in a view along the axis of rotation, and

fig. 4: the outer part of the joint according to fig. 1 to 3 is shown in a side view in section.

Detailed Description

Fig. 1 shows a ball-type synchronous universal joint 1 in a view along a rotational axis 3. Fig. 2 shows the joint outer part 2 of the ball-and-socket joint 1 according to fig. 1 in section in a view along the axis of rotation 3. Fig. 3 shows a detail Z of the joint outer part 2 according to fig. 2 in a view along the rotation axis 3 in section. Fig. 4 shows the outer joint part 2 according to fig. 1 to 3 in a side view in section B-B according to fig. 2. Fig. 1 to 4 are explained together below.

The ball-type synchronous joint 1 comprises a joint outer part 2, which has a rotational axis 3 and an outer ball track 4, a joint inner part 5, which has an inner ball track 6 and a plurality of torque-transmitting balls 7, which are guided in the outer ball track 4 and the inner ball track 4, respectively, which are assigned to one another, and additionally a cage 8, which is provided with a plurality of cage windows 9, which each receive one of the balls 7. The outer ball tracks 4 are arranged on the inner circumferential surface 10 of the joint outer part 5 and are arranged here in a distributed manner along the circumferential direction 11 and extend at least in an axial direction 12 parallel to the rotational axis 3.

A support surface 13 for contacting the cage 8 is arranged between the two outer ball tracks 4. In a cross section 14 of the joint outer part 2 extending transversely to the axis of rotation 3, at least one sub-region 15 of each support surface 13 extends along a diameter 16 with a common nominal dimension. Each of the sub-regions 15 extends across at least three sections 18, 19, 20 along the circumferential direction 11; wherein the second section 19 is arranged between the first section 18 and the third section 20 along the circumferential direction 11. A narrow tolerance 21 is provided for the second section 19 and a larger tolerance 22 is provided for the first section 18 and the third section 20, respectively, relative to the nominal dimension 17.

The second section 19 extends in the cross section 14 along the circumferential direction 11 over a first angular range 23, wherein the first section 18 and the third section 20 each extend over a second angular range 24, which is each smaller than the first angular range 23.

In the cross section 14, a maximum dimensional deviation from the nominal dimension 17 is defined by the respective tolerances 21, 22, wherein the maximum dimensional deviation in the first section 18 and the third section 20 is at least twice as large as in the second section 19.

The tolerances 21, 22 only achieve a dimensional deviation greater than the nominal dimension 17.

In the cross section 14, the transition between the support surface 13 and the ball tracks 4, 6 is defined by a radius 25.

The ball-type synchronous joint 1 is a ball-type synchronous displacement joint, wherein the total displacement travel 26 is defined by a corresponding maximum displacement of the joint inner part 5 relative to the joint outer part 2 along the rotational axis 3. The cross section 14 is arranged in an axial section 27 of the joint outer part 2, in which the ball 7 is arranged in operation provided for the ball-type synchronous joint 1.

In fig. 1, a shaft assembly 28 is indicated, which comprises at least the illustrated ball-and-socket joint 1 as well as a first shaft 29 connected to the joint outer part 2 and a second shaft 30 connected to the joint inner part 5.

List of reference numerals

1 ball type synchronous universal joint

2 Universal joint outer part

3 axis of rotation

4 external ball tracks (of joint external part)

5 Universal Joint inner part

6 (of inner part of joint) inner ball tracks

7 ball

8 retainer

9 cage window

10 inner peripheral surface

11 circumferential direction

12 axial direction

13 support surface

14 cross section

15 subregions

16 diameter

17 nominal size

18 first section

19 second section

20 third section

21 narrow tolerance

22 large tolerance

23 first angular range

24 second angular range

25 radius

26 total travel

27 axial section

28-axis assembly

29 first shaft

And a second axis 30.

Claims (10)

1. Ball-type synchronous universal joint (1) having at least a joint outer part (2) which has a rotational axis (3) and has an outer ball track (4), a joint inner part (5) which has an inner ball track (6) and a plurality of torque-transmitting balls (7) which are guided in the outer ball track (4) and the inner ball track (6) which are assigned to one another, respectively, or additionally having a cage (8) which is provided with a plurality of cage windows (9) which each receive one or more of the balls (7); wherein the outer ball track (4) is arranged on an inner circumferential surface (10) of the joint outer part (2) and is arranged here in a distributed manner along a circumferential direction (11) and extends at least along an axial direction (12) parallel to the rotational axis (3); wherein a support surface (13) for contacting the joint inner part (5) or the cage (8) is arranged between the two outer ball tracks (4); wherein, in at least one cross section (14) of the outer joint part (2) extending transversely to the rotational axis (3), at least one sub-region (15) of each support surface (13) extends along a diameter (16) with a common nominal dimension (17); wherein each of the sub-regions (15) extends across at least three sections (18, 19, 20) along the circumferential direction (11); wherein the second section (19) is arranged along the circumferential direction (11) between the first section (18) and the third section (20); wherein a narrow tolerance (21) is defined for the second section (19) and a larger tolerance (22) is defined for the first section (18) and the third section (20) with respect to the nominal dimension (17).

2. Ball-type synchronous joint (1) according to claim 1, wherein in the cross-section (14) the second section (19) extends along the circumferential direction (11) within a first angular range (23), wherein the first section (18) and the third section (20) each extend within a second angular range (24) which is respectively smaller than the first angular range (23).

3. Ball-type synchronous joint (1) according to any of the preceding claims, wherein in the cross section (14) a maximum dimensional deviation from the nominal dimension (17) is defined by respective tolerances (21, 22); wherein the maximum dimensional deviation in the first section (18) and the third section (20) is at least twice the maximum dimensional deviation in the second section (19).

4. Ball-type synchronous joint (1) according to any of the preceding claims, wherein the tolerance (21, 22) only achieves a dimensional deviation greater than the nominal dimension (17).

5. Ball-type synchronous joint (1) according to any of the preceding claims, wherein in the cross section (14) the transition between the bearing surface (13) and the outer ball track (4) is defined by a radius (25).

6. Ball-type synchronous joint (1) according to any of the preceding claims, wherein the joint outer part (2) is a forging; wherein at least the support surface (13) arranged in the cross section (14) is formed exclusively by forging, i.e. in particular without mechanical post-treatment.

7. Ball-type synchronous joint (1) according to any of the preceding claims, wherein the ball-type synchronous joint (1) is a ball-type synchronous mobile joint, wherein the total travel (26) of the joint inner part (5) relative to the joint outer part (2) is at least 5 mm.

8. Ball-type synchronous joint (1) according to any of the preceding claims, wherein the cross section (14) is arranged in an axial section (27) of the joint outer part (2), in which axial section the ball (7) is arranged in operation provided for the ball-type synchronous joint (1).

9. Ball-type synchronous joint (1) according to any of the preceding claims, wherein the ball-type synchronous joint (1) has at least four balls (7).

10. Shaft assembly (28) comprising at least a ball-type synchronous joint (1) according to any of the preceding claims 1 to 9 and a first shaft (29) connected to the joint outer part (2) and a second shaft (30) connected to the joint inner part (5).