Constant velocity joint
By designing paired inner and outer rolling member tracks, alternately setting convex and concave curvature radius is solved, and the problem of the difficulty of the medium-level constant speed joints in the prior art is difficult to take into account small mass, small packaging and high mechanical efficiency, achieving compact and efficient Joint design.
Patent Information
- Application Number
- CN202411137935.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2023-08-17
- Filing Date
- 2024-08-19
- Publication Date
- 2025-02-21
AI Technical Summary
Existing constant speed joints are difficult to take into account in the pursuit of small mass, small packaging and high mechanical efficiency, and often lead to increased package size or click noise.
A constant speed joint is designed, which includes an inner race and an outer race, which extends about a common central axis of rotation. The inner rolling member track and the outer rolling member track are arranged in a pairing relationship. The curvature radius of the inner rolling member track and the curvature radius of the outer rolling member track alternately in convex and concave shapes, and the radius of curvature can be set as a non-constant mathematical function as needed.
Achieving isospeed joints with small mass, small packages and high mechanical efficiency reduces package size and noise, meeting the needs of efficient and compact designs.
Smart Images
Figure CN119491878A_ABST
Abstract
Description
[0001] Related Applications
[0002] This application claims the benefit of U.S. Provisional Application Serial No. 63 / 533,342, filed on August 17, 2023, the entire contents of which are incorporated herein by reference. Technical Field
[0003] The present disclosure relates generally to axle assemblies for motor vehicles, and more particularly to constant velocity joints (CVJs) for axle assemblies. Background Art
[0004] There is an increasing demand for constant velocity joints (CVJs) for automotive axle joint applications to have low mass, small footprint and high mechanical efficiency. In order to improve mechanical efficiency, it is known to incorporate a straight helical ball track, however, this generally results in an increase in package size. In order to be able to reduce package size, a reduction in the helix angle may be employed, however, this generally results in an increase in rattling noise.
[0005] Therefore, there is a need for a constant velocity joint that at least overcomes the above disadvantages while having low mass, small footprint and high mechanical efficiency. Summary of the invention
[0006] One aspect of the present disclosure provides a constant velocity joint, which includes an inner race having opposite inner race sides, wherein a plurality of inner rolling member tracks follow an inner rolling member track spiral path relative to a central rotation axis. Each inner rolling member track has an inner rolling member track curvature radius extending from one of the inner race sides to another of the inner race sides. An outer race is arranged around the inner race so that the inner race and the outer race extend around a common central rotation axis. The outer race has opposite outer race sides, wherein a plurality of outer rolling member tracks follow an outer rolling member track spiral path relative to the central rotation axis. Each outer rolling member track has an outer rolling member track curvature radius extending from one of the outer race sides to another of the outer race sides. The outer rolling member track is arranged in a paired relationship with the inner rolling member track to define a plurality of rolling member raceways. At least one rolling member is arranged in each of the rolling member raceways to be rolled and received in the inner rolling member track and the outer rolling member track. At least one inner rolling member track radius of curvature has a convex radius of curvature while the mating outer rolling member track radius of curvature has a concave radius of curvature, and at least one inner rolling member track radius of curvature has a concave radius of curvature while the mating outer rolling member track radius of curvature has a convex radius of curvature.
[0007] According to another aspect of the present disclosure, a constant velocity joint is provided, the constant velocity joint comprising: an inner race; and an outer race, the outer race being arranged around the inner race so that the inner race and the outer race extend around a common central rotation axis. The inner race has opposite inner race sides, wherein a plurality of inner rolling member tracks extend from one of the inner race sides to another of the inner race sides along a spiral path relative to the central rotation axis. The outer race has opposite outer race sides, wherein a plurality of outer rolling member tracks extend from one of the outer race sides to another of the outer race sides along a spiral path relative to the central rotation axis. The outer rolling member tracks are arranged in a paired relationship with the inner rolling member tracks to define a plurality of rolling member raceways extending in a spiral relationship relative to the central rotation axis. At least one rolling member is arranged in each of the rolling member raceways to be rollingly received in the inner rolling member track and the outer rolling member track. Each of the inner rolling member tracks has an inner rolling member track curvature radius extending from one of the inner race side surfaces to another of the inner race side surfaces. Each of the outer rolling member tracks has an outer rolling member track curvature radius extending from one of the outer race side surfaces to another of the outer race side surfaces. The inner rolling member track curvature radius of at least one of the inner rolling member tracks has a radius origin offset from the central rotation axis.
[0008] These and other aspects, objects, advantages and features will become apparent to those of ordinary skill in the art from the following description taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS
[0009] The subject matter regarded as the invention is particularly pointed out and distinctly claimed in the claims at the conclusion of this specification. The foregoing and other features and advantages of the invention will be apparent from the following detailed description taken in conjunction with the accompanying drawings, in which:
[0010] Figure 1A is a cross-sectional view taken generally along a longitudinal center axis of a stroking constant velocity joint constructed in accordance with one aspect of the present disclosure;
[0011] Figure 1B It is roughly observed along line 1B Figure 1A A front view of a stroke constant velocity joint with the cage removed for clarity purposes only;
[0012] Figure 2 yes Figure 1A-1Ba front view of an inner race of a constant velocity joint of , showing an inner ball track that follows an inner ball track helical path relative to a central axis and has an inner ball track radius of curvature extending from one of the inner race sides to another of the inner race sides;
[0013] Figure 3A It is roughly along Figure 2 Observe the direction of arrow 3A Figure 2 A side view of the inner race;
[0014] Figure 3B It is roughly along Figure 3A A schematic diagram of a convex ball track path intercepted by line 3B-3B;
[0015] Figure 4A It is roughly along Figure 2 Observe the direction of arrow 4A Figure 2 A side view of the inner race;
[0016] Figure 4B It is roughly along Figure 4A The line 4B-4B is intercepted for Figure 2 A schematic diagram of the concave ball track path of the even-numbered ball tracks identified in;
[0017] Figure 5 is similar to Figure 3B , showing a convex ball track path having a non-constant, variable radius of curvature;
[0018] Figure 6 is similar to Figure 4B , showing a concave ball track path having a non-constant, variable radius of curvature;
[0019] Fig. 7A It is roughly along Figure 1B A cross-sectional view of the outer race of the constant velocity joint taken along line 7A-7A;
[0020] Figure 7B It is roughly along Fig. 7A A schematic diagram of a concave ball track path intercepted by line 7B-7B;
[0021] Fig. 8A It is roughly along Figure 1B A cross-sectional view of the outer race of the constant velocity joint taken along line 8A-8A; and
[0022] Figure 8B It is roughly along Fig. 8A Schematic diagram of the convex ball track path intercepted by line 8B-8B. DETAILED DESCRIPTION
[0023] Referring now to the accompanying drawings, in which the invention will be described with reference to specific embodiments without limiting the invention, Figure 1A-1B A stroke constant velocity joint, also referred to as a constant velocity joint (CVJ) 10, constructed in accordance with one aspect of the present disclosure is shown. The CVJ 10 includes an inner race 12 having opposing inner race sides (also referred to as inner sides 12a, 12b), with a plurality of individual inner rolling member tracks (also referred to as inner ball tracks 14) extending from one of the inner race sides 12a to the other of the inner race sides 12b. Thus, the inner ball tracks 14 are circumferentially spaced from one another in an equidistant relationship to one another around the periphery of the inner race 12. The CVJ 10 also includes an outer race 16, wherein the outer race 16 is disposed about the inner race 12 such that the inner race 12 and the outer race 16 extend about a common central axis of rotation (referred to as central axis 18). The outer race 16 has opposite outer race sides (also referred to as outer sides 16a, 16b), and a plurality of outer rolling member tracks (also referred to as outer ball tracks 20) extend from one of the outer race sides to another of the outer race sides. Therefore, the outer ball tracks 20 are circumferentially spaced apart from each other in an equidistant relationship around the inner circumference of the outer race 16. The inner ball track 14 and the outer ball track 20 are radially aligned with each other in a matching relationship (also referred to as a facing relationship or a mating relationship) to define a plurality of rolling member raceways (referred to as raceways R) therebetween, as is known in the art. A plurality of rolling members 22 (such as spherical balls) are disposed between the inner race 12 and the outer race 16, wherein at least one rolling member 22 is positioned to be rollingly received in each raceway R defined by the inner ball track 14 and the outer ball track 20. A retaining cage 23 ( Figure 1A ) to guide these rolling members 22 in their respective inner ball tracks 14 and outer ball tracks 20. Each of the inner ball tracks 14 follows an inner ball track spiral path relative to the central axis 18 and has an inner ball track curvature radius ( ) extending from one of the inner race side surfaces 12a to another of the inner race side surfaces 12b. FIG. 3A to FIG. 4B Each of the outer ball tracks 20 follows an outer ball track spiral path relative to the central axis 18 and has an outer ball track curvature radius ( ) extending from one of the outer race side surfaces 16a to another of the outer race side surfaces 16b. 7A to 8B ).
[0024] The cage 23 has a plurality of pockets corresponding to the number of rolling members 22, the size of the pockets being adapted to loosely receive the rolling members therein. The cage 23 has an outer surface 25, the size of which is adapted to be received in the aperture of the outer race 16, wherein the size of the outer surface 25 is adapted to form a gap with the generally cylindrical radially innermost cylindrical surface 30 of the outer race 16. The cage 23 has an inner surface 27, the size of which is adapted to form a gap with the radially outermost convex surface 32 of the inner race 12. The outer surface 25 and the inner surface 27 extend generally axially between the opposing cage sides 23a, 23b.
[0025] According to one aspect of the present disclosure, Figure 3A and Figure 3B As best shown in FIG. 1 , at least one inner rolling member track radius of curvature has a convex inner rolling member track radius of curvature (also referred to as a convex inner radius of curvature 24a) extending from one side 12a to an opposite side 12b, and as shown in FIG. Fig. 7A and Figure 7B As best shown in FIG. 1 , the paired outer rolling member track radius of curvature has a concave outer rolling member track radius of curvature (also referred to as concave outer radius of curvature 26a) extending from one side 16a to the opposite side 16b. Figure 4A and Figure 4B As best shown in FIG. 1 , at least one inner rolling member track radius of curvature has a concave inner rolling member track radius of curvature (also referred to as concave inner radius of curvature 24b) extending from one side 12a to the opposite side 12b, and as shown in FIG. Fig. 8A and Figure 8B As best shown in FIG. 2 , the mating outer rolling member track radius of curvature has a convex outer rolling member track radius of curvature (also referred to as a convex outer radius of curvature 26 b ).
[0026] According to one aspect of the present disclosure, every other inner ball track 14 may be configured to have a convex inner radius of curvature 24a, wherein the paired outer ball track 20 has a concave outer radius of curvature 26a, and every other inner ball track 14 may be configured to have a concave inner radius of curvature 24b, wherein the paired outer ball track 20 has a convex outer radius of curvature 26b. Thus, the convex and concave surfaces of the inner ball tracks 14 alternate with each other, and the convex and concave surfaces of the outer ball tracks 20 alternate with each other, wherein the convex inner ball tracks 14 are paired with the concave outer ball tracks 20, and the concave inner ball tracks 14 are paired with the convex outer ball tracks 20.
[0027] According to another aspect of the present disclosure, the inner ball track curvature radius (whether formed as a convex inner curvature radius 24a or a concave inner curvature radius 24b) can be formed so that the radius forming the concave curvature or the convex curvature is not constant, wherein the constant radius is Figure 5 and Figure 6Therefore, the convex inner curvature radius 24a ( Figure 5 ) and the concave inner curvature radius 24b ( Figure 6 ) may follow a second-order (also called quadratic), third-order, or higher-order polynomial mathematical function (as an example and not limitation). Thus, the convex inner curvature radius 24a ( Figure 5 ) and the concave inner radius of curvature 24b are not constant. Likewise, the outer ball track radius of curvature may be formed so that it is not constant, but follows a similar mathematical function to the inner ball track radius of curvature. The inner rolling member track radius of curvature and the outer rolling member track radius of curvature (whether they are constant or non-constant) may be arranged to be equally spaced from each other along their entirety, thereby providing a raceway R of uniform size.
[0028] According to another aspect of the present disclosure, Figure 2 As shown, every other inner rolling member track 14 may be configured to have a left-hand spiral around the central axis 18, and the outer rolling member track 20 paired with the left-hand spiral inner rolling member track 14 has a right-hand spiral around the central axis 18. In addition, every other inner rolling member track 14 may be configured to have a right-hand spiral around the central axis 18, and the outer rolling member track 20 paired with the right-hand spiral inner rolling member track 14 has a left-hand spiral around the central axis 18. Therefore, in the case where the inner ball track 14 has a left-hand spiral, the paired outer ball track 20 has a right-hand spiral, and vice versa.
[0029] According to yet another aspect of the present disclosure, at least one of the inner rolling member track curvature radii 24a, 24b and the outer rolling member track curvature radii 26a, 26b has a radius origin that is offset from (also referred to as being radially spaced from) the central axis 18. For example, Figure 3B As shown, the origin 28a of the convex inner radius of curvature 24a is arranged to be spaced apart from the central axis 18, wherein the central axis 18 is located between the origin 28a and the corresponding convex inner rolling member track 14. Figure 4B As shown, the origin 28b of the concave inner radius of curvature 24b is arranged to be spaced from the central axis 18, wherein the inner rolling member track 14 is located between its radius origin 28b and the central axis 18. The offset of the origin 28a, 28b can be combined with an inner race 12 having all convex inner radius of curvature 24a, all concave inner radius of curvature 24b, or a mixture of convex inner radius of curvature 24a and concave inner radius of curvature 24b.
[0030] The outer surface 25 and the inner surface 27 of the cage have corresponding concentric radii of curvature 34, 36, so as to have a common radial origin. The outer radius of curvature 34 is sized to form a gap with the inner surface 30 of the outer race 16, so as to allow the cage 23 to perform axial plunging movement relative to the outer race 16, and the inner radius of curvature 36 is greater than the radius of curvature of the convex surface 32 of the inner race, so as to facilitate relative pivoting movement with the inner race 12.
[0031] Although the present invention has been described in detail in conjunction with only a limited number of embodiments, it should be readily understood that the present invention is not limited to these disclosed embodiments. On the contrary, the present invention may be modified to include any number of changes, modifications, permutations, or equivalent arrangements that have not been described heretofore but are commensurate with the spirit and scope of the present invention. In addition, although various embodiments of the present invention have been described, it should be understood that various aspects of the present invention may include only some of the embodiments described. The various elements or features of a particular embodiment are generally not limited to the particular embodiment, but are interchangeable and can be used in selected embodiments where applicable, even if not explicitly shown or described. Therefore, the present invention should not be considered to be limited by the foregoing description.
Claims
1. A constant velocity joint, comprising: an inner race having opposed inner race sides, wherein a plurality of inner rolling member tracks follow an inner rolling member track spiral path relative to a central rotational axis, each inner rolling member track having an inner rolling member track radius of curvature extending from one of the inner race sides to another of the inner race sides; an outer race disposed about the inner race so that the inner race and the outer race extend about a common central axis of rotation, the outer race having opposing outer race sides, wherein a plurality of outer rolling member tracks follow an outer rolling member track spiral path relative to the central axis of rotation, each outer rolling member track having an outer rolling member track radius of curvature extending from one of the outer race sides to another of the outer race sides, the outer rolling member tracks being arranged in paired relationship with the inner rolling member tracks to define a plurality of rolling member raceways; as well as at least one rolling member disposed in each of the rolling member raceways to be rollingly received in the inner and outer rolling member tracks, wherein at least one inner rolling member track radius of curvature has a convex radius of curvature and the paired outer rolling member track radius of curvature has a concave radius of curvature, At least one of the inner rolling member track radius of curvature has a concave radius of curvature and the mating outer rolling member track radius of curvature has a convex radius of curvature.
2. The constant velocity joint of claim 1 , wherein every other inner rolling member track radius of curvature has a convex radius of curvature, wherein the paired outer rolling member track radius of curvature has a concave radius of curvature, and every other inner rolling member track radius of curvature has a concave radius of curvature, wherein the paired outer rolling member track radius of curvature has a convex radius of curvature.
3. The constant velocity joint of claim 1 , wherein every other inner rolling member track has a left-hand helix around the central rotation axis, wherein the outer rolling member track paired with the left-handed inner rolling member track has a right-hand helix around the central rotation axis, and every other inner rolling member track has a right-hand helix around the central rotation axis, wherein the outer rolling member track paired with the right-handed inner rolling member track has a left-hand helix around the central rotation axis.
4. The constant velocity joint of claim 3, wherein every other inner rolling member track radius of curvature has a convex radius of curvature, wherein the corresponding outer rolling member track radius of curvature paired with the convex radius of curvature has a concave radius of curvature, and every other inner rolling member track radius of curvature has a concave radius of curvature, wherein the corresponding outer rolling member track radius of curvature paired with the concave radius of curvature has a convex radius of curvature.
5. The constant velocity joint of claim 1, wherein the constant velocity joint is a stroke joint that allows relative axial movement between the inner race and the outer race along the central rotational axis.
6. The constant velocity joint of claim 1, wherein the inner rolling member track radius of curvature is not constant.
7. The constant velocity joint of claim 6, wherein the outer rolling member track radius of curvature is not constant.
8. The constant velocity joint of claim 7, wherein the inner and outer rolling member track radii of curvature are equidistantly spaced from one another along their entirety.
9. The constant velocity joint of claim 1, wherein at least one of the inner rolling member track radius of curvature and the outer rolling member track radius of curvature has a radius origin that is offset from the central rotational axis.
10. A constant velocity joint, comprising: an inner race having opposed inner race sides, wherein a plurality of inner rolling member tracks follow an inner rolling member track spiral path relative to a central rotational axis, each inner rolling member track having an inner rolling member track radius of curvature extending from one of the inner race sides to another of the inner race sides; an outer race disposed about the inner race so that the inner race and the outer race extend about a common central axis of rotation, the outer race having opposing outer race sides, wherein a plurality of outer rolling member tracks follow an outer rolling member track spiral path relative to the central axis of rotation, each outer rolling member track having an outer rolling member track radius of curvature extending from one of the outer race sides to another of the outer race sides, the outer rolling member tracks being arranged in paired relationship with the inner rolling member tracks to define a plurality of rolling member raceways; as well as at least one rolling member disposed in each of the rolling member raceways to be rollingly received in the inner and outer rolling member tracks, wherein the inner rolling member track radius of curvature of at least one of the inner rolling member tracks has a radius origin offset from the central axis of rotation.
11. The constant velocity joint of claim 10, wherein the central rotational axis is located between a radius origin of at least one inner rolling member track and the corresponding inner rolling member track.
12. The constant velocity joint of claim 11, wherein each inner rolling member track radius of curvature is convex.
13. The constant velocity joint of claim 11, wherein at least one inner rolling member track is located between its corresponding radius origin and the central rotational axis.
14. The constant velocity joint of claim 13, wherein at least one inner rolling member track radius of curvature is convex and at least one inner rolling member track radius of curvature is concave.
15. The constant velocity joint of claim 14, wherein every other inner rolling member track radius of curvature is convex, wherein the mating outer rolling member track radius of curvature is concave, and every other inner rolling member track radius of curvature is concave, wherein the mating outer rolling member track radius of curvature is convex.
16. The constant velocity joint of claim 10, wherein at least one inner rolling member track is located between its corresponding radius origin and the central rotational axis.
17. A constant velocity joint according to claim 16, wherein each inner rolling member track radius of curvature is concave or convex.
18. The constant velocity joint of claim 10, wherein the outer rolling member track radius of curvature of at least one of the outer rolling member tracks has a radius origin that is offset from the central axis of rotation.
19. The constant velocity joint of claim 18, wherein the central axis of rotation is located between a radius origin of at least one outer rolling member track and the corresponding outer rolling member track.
20. The constant velocity joint of claim 19, wherein at least one outer rolling member track is located between its corresponding radius origin and the central rotational axis.