A conical rolling element universal joint
By leveraging the synergistic effect of the cage unit and the elastic components, the problem of unstable relative position of the rolling elements in the universal joint is solved, achieving stable force transmission under low cost and small space, thus improving the performance and reliability of the universal joint.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- WANXIANGQIANCHAO CO LTD
- Filing Date
- 2026-03-27
- Publication Date
- 2026-06-23
AI Technical Summary
Under the conditions of low cost and small space, how to ensure that the rolling elements in the rolling element universal joint maintain the stability of their relative positions during movement, and avoid the interruption of force flow or stress concentration caused by the misalignment of individual rolling elements?
By employing the synergistic effect of the cage unit and the elastic component, the small-diameter end of the rolling assembly is precisely constrained by the retaining groove of the cage unit, and the axial preload is applied to the large-diameter end of the rolling assembly by the elastic component, thus achieving bidirectional constraint and ensuring the stable rotation of the rolling assembly within the receiving cavity.
Under low cost and small space conditions, the relative position stability of the rolling components is achieved, ensuring smooth and reliable force transmission of the universal joint, reducing production costs and minimizing friction and jamming risks.
Smart Images
Figure CN121916247B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of universal joint technology, and more specifically, to a conical rolling element universal joint. Background Technology
[0002] In the field of mechanical transmission, universal joints are key components for transmitting power at varying angles. For universal joints that rely on rolling elements for force transmission, their performance and lifespan largely depend on the coordination and consistency of these rolling elements during operation. When structural space is limited and cost is constrained, ensuring that these rolling elements maintain their preset relative positions during movement, and avoiding interruptions in force flow or stress concentration due to the misalignment of individual rolling elements, becomes a common technical challenge. This stability issue directly restricts the performance of such universal joints in low-cost, high-reliability applications.
[0003] To maintain the stable alignment of rolling elements, existing technologies often require a difficult trade-off between design precision and manufacturing cost. High-precision manufacturing and assembly can improve this problem, but significantly increase costs; while overly simplified structures struggle to effectively constrain the rolling elements under dynamic conditions, leading to unstable transmission and premature wear. Therefore, finding an effective intrinsic constraint mechanism within limited space and cost constraints to ensure all rolling elements work collaboratively as a whole, thereby achieving smooth and stable force transmission, is a key problem that those skilled in the art have long strived to solve. Summary of the Invention
[0004] To address the problem of ensuring the relative positional stability of rolling components under low-cost and compact conditions, this invention provides a conical rolling element universal joint, comprising:
[0005] cross shaft assembly;
[0006] The bushing unit is fitted onto the cross shaft assembly;
[0007] A sealing assembly is located between the bushing unit and the cross shaft assembly and is sleeved on the cross shaft assembly; the sealing assembly, the bushing unit, and the cross shaft assembly together form a receiving cavity;
[0008] The cage unit is fitted onto the cross shaft assembly and located at the end of the receiving cavity away from the sealing assembly;
[0009] Multiple rolling assemblies, the diameter of which gradually increases along a first direction; multiple rolling assemblies are disposed in a receiving cavity and spaced apart circumferentially along the cross shaft assembly; wherein, a cage unit is provided with a number of retaining grooves spaced apart circumferentially along the cross shaft assembly; the small-diameter end of the rolling assembly is located in the retaining groove and abuts against the cage unit;
[0010] The elastic component is located within the receiving cavity and between the sealing component and the rolling component; the elastic component is sleeved on the cross shaft assembly; wherein, the large diameter end of the rolling component abuts against the elastic component; the interaction force between the rolling component and the elastic component is greater than zero.
[0011] In some embodiments, the sealing assembly includes a sealing unit and a skeleton unit; the sealing unit is sleeved on the cross shaft assembly and abuts against at least a portion of the elastic component; the skeleton unit includes an integrally formed first skeleton portion and a second skeleton portion; the first skeleton portion is embedded in the sealing unit along a second direction; a portion of the second skeleton portion is embedded in the sealing unit along a first direction; wherein, one end of the second skeleton portion is connected to the first skeleton portion; the other end of the second skeleton portion extends along the first direction and abuts against the bushing unit; the first direction and the second direction are perpendicular to each other.
[0012] In some embodiments, the skeleton unit further includes a reinforcing portion; the reinforcing portion is supported at the connection between the first skeleton portion and the second skeleton portion.
[0013] In some embodiments, the bushing unit has a limiting portion on the inner peripheral wall facing the cross shaft assembly; one end of the second skeleton portion is connected to the first skeleton portion; and the other end of the second skeleton portion abuts against the limiting portion.
[0014] In some embodiments, at least a portion of the elastic component abuts against the sealing unit on the side away from the rolling component; wherein the projection of the abutment between the elastic component and the sealing unit along a first direction covers the second skeleton portion.
[0015] In some embodiments, the large-diameter end of the rolling assembly contacts the outer peripheral wall of the cross shaft assembly and the inner peripheral wall of the bushing unit.
[0016] In some embodiments, a portion of the outer peripheral side of the minor diameter end of the rolling assembly has a gap with the outer peripheral wall of the cross shaft assembly and the inner peripheral wall of the bushing unit.
[0017] In some embodiments, the bushing unit is provided with a first lubrication groove; the first lubrication groove communicates with the receiving cavity; the cage unit covers the first lubrication groove along the axial projection of the cross shaft assembly.
[0018] In some embodiments, the cage unit is provided with a second lubrication groove; the second lubrication groove is connected to the receiving cavity and the first lubrication groove respectively.
[0019] In some embodiments, one side of the cage unit has a gap with the outer peripheral wall of the cross shaft assembly; the opposite side of the cage unit contacts the inner peripheral wall of the bushing unit.
[0020] To address the problem of ensuring the relative position stability of the rolling components under low-cost and compact conditions, this invention offers the following advantages:
[0021] The cage unit and the elastic component work together to provide bidirectional axial constraint and positioning for the rolling components. The cage unit, located within the small space of the housing cavity, precisely constrains the small-diameter ends of all rolling components from one side via its retaining grooves, effectively preventing radial movement and skew. Meanwhile, the elastic component continuously applies axial preload to the large-diameter ends of the rolling components from the other side, eliminating assembly clearance between the cage unit and the rolling components and ensuring that all rolling components rotate tightly and stably within the housing cavity under dynamic conditions. This integrated dual-constraint mechanism, with its low-cost structure introduced within the small space of the housing cavity, fundamentally guarantees the stability of the relative positions of all rolling components, thereby achieving smooth and reliable force transmission in the universal joint. Attached Figure Description
[0022] Figure 1 A perspective view of a universal joint dustproof structure according to one embodiment is shown;
[0023] Figure 2 A cross-sectional view of a universal joint dustproof structure according to one embodiment is shown;
[0024] Figure 3 A partial schematic diagram (A) of a universal joint dustproof structure according to one embodiment is shown;
[0025] Figure 4 A schematic diagram of the rolling assembly of a universal joint dustproof structure according to one embodiment is shown;
[0026] Figure 5 A schematic diagram of a retainer assembly of a universal joint dustproof structure according to one embodiment is shown.
[0027] Figure label:
[0028] 10. Cross shaft assembly; 11. Cross shaft unit; 12. Journal unit; 20. Bushing assembly; 21. Bushing unit; 22. Limiting part; 23. First lubrication groove; 30. Sealing assembly; 31. Sealing unit; 32. Skeleton unit; 321. First skeleton part; 322. Second skeleton part; 40. Elastic assembly; 50. Rolling assembly; 60. Cage assembly; 61. Cage unit; 62. Cage groove; 63. Second lubrication groove. Detailed Implementation
[0029] The present disclosure will now be discussed with reference to several exemplary embodiments. It should be understood that these embodiments are discussed only to enable those skilled in the art to better understand and thus implement the present disclosure, and are not intended to imply any limitation on the scope of the disclosure.
[0030] As used herein, the term "comprising" and its variations are to be interpreted as open-ended terms meaning "including but not limited to". The term "based on" is to be interpreted as "at least partially based on". The terms "one embodiment" and "an embodiment" are to be interpreted as "at least one embodiment". The term "another embodiment" is to be interpreted as "at least one other embodiment". The terms "upper", "lower", "left", "right", "front", "rear", "top", "bottom", "inner", "outer", "vertical", "horizontal", "lateral", "longitudinal", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. These terms are primarily for the purpose of better describing this application and its embodiments and are not intended to limit the indicated devices, elements, or components to having a specific orientation or being constructed and operated in a specific orientation. Furthermore, some of the above terms may be used to indicate other meanings besides orientations or positional relationships; for example, the term "upper" may in some cases indicate a dependency or connection relationship. Those skilled in the art can understand the specific meaning of these terms in this application according to the specific circumstances. In addition, the terms "installed", "set up", "equipped with", "connected", and "linked" should be interpreted broadly. For example, it can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or an internal connection between two devices, elements, or components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances. Furthermore, the terms "first," "second," etc., are mainly used to distinguish different devices, elements, or components (the specific types and structures may be the same or different), and are not used to indicate or imply the relative importance or quantity of the indicated devices, elements, or components. Unless otherwise stated, "a plurality of" means two or more.
[0031] To achieve smooth and reliable force transmission in universal joints, existing technologies typically significantly improve the machining and assembly precision of each component, aiming to ensure the relative position stability of the rolling elements through the dimensional accuracy of the parts themselves. However, this approach not only places stringent demands on the manufacturing process, leading to a significant increase in production costs, but also makes it difficult to maintain its initial precision under long-term motion and wear. Therefore, this invention provides a tapered rolling element universal joint to solve the problem of ensuring the relative position stability of the rolling assembly 50 under low-cost and compact conditions.
[0032] Please refer to Figure 1 , Figure 2 and Figure 3An embodiment of the present invention provides a tapered rolling element universal joint, which includes: a cross shaft assembly 10, a bushing unit 21, a sealing assembly 30, a cage unit 61, a plurality of rolling assemblies 50, and an elastic assembly 40.
[0033] Specifically, the bushing unit 21 is sleeved on the cross shaft assembly 10; the sealing assembly 30 is located between the bushing unit 21 and the cross shaft assembly 10 and is sleeved on the cross shaft assembly 10; the sealing assembly 30, the bushing unit 21 and the cross shaft assembly 10 enclose a receiving cavity to form a working chamber for accommodating parts such as the rolling assembly 50 and the cage unit 61.
[0034] Specifically, the cage unit 61 is fitted onto the cross shaft assembly 10 and located at the end of the receiving cavity away from the sealing assembly 30. The receiving cavity adapts to the shape based on the gradually increasing diameter of the rolling assembly 50 along the first direction, that is, the receiving cavity has a tapered shape when viewed from a cross-sectional angle. The location of the cage unit 61 at the end of the receiving cavity away from the sealing assembly 30 allows the cage unit 61 to be manufactured with a smaller volume, which not only reduces manufacturing costs but also reduces the overall weight of the universal joint.
[0035] Multiple rolling components 50 are disposed within the receiving cavity and spaced apart circumferentially along the cross shaft assembly 10; wherein, the cage unit 61 is provided with a plurality of retaining grooves 62 spaced apart circumferentially along the cross shaft assembly 10; the small-diameter end of the rolling component 50 is located in the retaining groove 62 and abuts against the cage unit 61, so that the rolling component 50 can be positioned in the retaining groove 62, so that the rolling component 50 can rotate independently in the retaining groove 62 without interfering or colliding with adjacent rolling components 50.
[0036] The elastic component 40 is located within the receiving cavity and between the sealing component 30 and the rolling component 50. The elastic component 40 is sleeved on the cross shaft assembly 10. The large-diameter end of the rolling component 50 abuts against the elastic component 40; the interaction force between the rolling component 50 and the elastic component 40 is greater than zero, allowing the elastic component 40 to continuously apply axial preload to the large-diameter end of the rolling component 50. This not only eliminates the assembly gap between the cage unit 61 and the rolling component 50, but also ensures that all rolling components 50 can always rotate tightly and stably within the receiving cavity under dynamic operating conditions.
[0037] For details, please refer to Figure 1 , Figure 2 and Figure 3The cross shaft assembly 10 includes a cross shaft unit 11 and four journal units 12 connected to the cross shaft unit 11. The four journal units 12 are connected to the cross shaft unit 11 along two central axes, which are perpendicular to each other. A bushing unit 21, a sealing assembly 30, and a retainer unit 61 are all fitted onto the journal units 12. The sealing assembly 30, bushing unit 21, and journal units 12 together form a receiving cavity. The retainer assembly 60 includes a retainer unit 61 and retaining grooves 62. The retaining grooves 62 are spaced circumferentially on the retainer unit 61. The retainer unit 61 and the elastic assembly 40 are both located within the receiving cavity and fitted onto the journal units 12. The receiving cavity is filled with lubricating oil or grease to lubricate the rotation of the internal parts, thereby reducing friction between the parts; the specific application will vary.
[0038] Please refer to Figure 3 In this embodiment, the large-diameter end of the rolling assembly 50 contacts the outer peripheral wall of the journal unit 12 and the inner peripheral wall of the bushing unit 21 of the cross shaft assembly 10.
[0039] Furthermore, the rolling component 50 may be, for example, a conical rolling element, depending on the actual application, and is not specifically limited in this invention. The diameter of the rolling component 50 gradually increases along a first direction, which is the direction from the end face of the bushing component 20 to the elastic component 40, depending on the actual application.
[0040] Understandably, the larger diameter end of the rolling assembly 50 is the large-diameter end. This large-diameter end contacts both the outer peripheral wall of the journal unit 12 and the inner peripheral wall of the bushing unit 21, forming the main force and transmission path. It is responsible for bearing the working load and receiving the axial preload from the elastic component 40, depending on the actual application. The smaller diameter end of the rolling assembly 50 is the small-diameter end, which is constrained within the retaining groove 62 of the cage unit 61, providing precise radial positioning and guidance for the rolling assembly 50. The central axis of the rolling assembly 50 is parallel to the central axis of the journal unit 12, depending on the actual application.
[0041] Understandably, when a tapered rolling element universal joint transmits torque, the rolling component 50 has the strongest rigidity and the largest cross-sectional area at its large diameter end. This means that the force transmission path is completed through the large diameter end, allowing the rolling component 50 to withstand higher loads and making the force flow transmission more direct and efficient. This improves the load-bearing capacity and transmission rigidity of the tapered rolling element universal joint.
[0042] In this embodiment, a portion of the outer peripheral side of the small diameter end of the rolling assembly 50 has a gap with the outer peripheral wall of the cross shaft assembly 10 and the inner peripheral wall of the bushing unit 21.
[0043] Understandably, a gap exists between the outer peripheral side of the small-diameter end of the rolling assembly 50 and the outer peripheral wall of the journal unit 12 and the inner peripheral wall of the bushing unit 21. This gap ensures that the small-diameter end does not participate in the transmission of the main load, thereby avoiding damage caused by stress concentration. At the same time, this gap also provides space for the flow or thermal expansion of lubricating oil or grease, reducing the risk of friction and jamming, making the rolling assembly 50 roll more smoothly, and reducing the machining cost of the finishing of the rolling assembly 50.
[0044] Please refer to Figure 5 It is understood that the end face of the small diameter end located in the retaining groove 62 can be arc-shaped. This arc shape is adapted to the shape and depth of the retaining groove 62, so that the small diameter end can rotate in the retaining groove 62 and be positioned in the retaining groove 62 without interfering with the adjacent rolling assembly 50. The specific shape is subject to actual application and is not specifically limited in this invention.
[0045] Please refer to Figure 3 In this embodiment, one side of the retainer unit 61 has a gap with the outer peripheral wall of the journal unit 12 of the cross shaft assembly 10; the other side of the retainer unit 61 is in contact with the inner peripheral wall of the bushing unit 21.
[0046] Understandably, due to the small space inside the receiving cavity, the retainer unit 61 is only set at the end of the receiving cavity away from the sealing assembly 30, which greatly reduces the production cost of the universal joint. The elastic assembly 40, based on the axial force applied by the movement of the rolling assembly 50, also continuously applies axial preload to the large diameter end of the rolling assembly 50 from the other side, ensuring that all rolling assemblies 50 are always stably rotating inside the receiving cavity under dynamic working conditions without interfering with each other, thereby ensuring the stability of force transmission.
[0047] Meanwhile, the gap between one side of the cage unit 61 and the outer peripheral wall of the journal unit 12 provides space for the smooth rotation of the cage unit 61 within the receiving cavity, and also reserves space for the flow or thermal expansion of lubricating oil or grease, reducing the risk of friction and jamming, and making the rotation of the cage unit 61 smoother. The opposite side of the cage unit 61 contacts the inner peripheral wall of the bushing unit 21, giving the cage unit 61 a pivot point for rotation and preventing random collisions within the receiving cavity, thus ensuring stable force transmission.
[0048] Please refer to Figure 5In this embodiment, the sealing assembly 30 includes a sealing unit 31 and a skeleton unit 32; the sealing unit 31 is sleeved on the journal unit 12 of the cross shaft assembly 10 and abuts against at least a portion of the elastic component 40; the skeleton unit 32 includes an integrally formed first skeleton portion 321 and a second skeleton portion 322; the first skeleton portion 321 is embedded in the sealing unit 31 along a second direction; a portion of the second skeleton portion 322 is embedded in the sealing unit 31 along a first direction; wherein, one end of the second skeleton portion 322 is connected to the first skeleton portion 321; the other end of the second skeleton portion 322 extends along the first direction and protrudes out of the sealing unit 31, and the other end of the second skeleton portion 322 abuts against the bushing unit 21; the first direction and the second direction are perpendicular to each other.
[0049] Specifically, the second direction is the direction perpendicular to the central axis of the corresponding journal unit 12, i.e., the radial direction of the journal unit 12. The integrally formed skeleton unit 32 enhances the overall structural strength and rigidity of the sealing assembly 30. The first skeleton part 321 and the second skeleton part 322 reinforce the sealing unit 31 from the second direction and the first direction, respectively. This not only improves the sealing reliability and prevents lubricant leakage and contaminant intrusion, but also provides a stable and reliable support surface for the elastic component 40, ensuring the effective transmission of preload.
[0050] In this embodiment, at least a portion of the elastic component 40 abuts against the sealing unit 31 on the side away from the rolling component 50, providing a stable support surface for the elastic component 40. Based on this support surface, the elastic component 40 can apply an axial force to the rolling component 50, ensuring that the rolling component 50 can rotate within the receiving cavity. The projection of the abutment point between the elastic component 40 and the sealing unit 31 along the first direction covers the second skeleton portion 322.
[0051] Understandably, the force applied by the elastic component 40 to the sealing component 30 can be borne by the second skeleton part 322, rather than entirely by the flexible sealing unit 31 material. This effectively avoids the sealing lip from deforming or wearing due to excessive axial pressure. While ensuring the pre-tightening function, it also ensures the stability of the sealing unit 31 position and guarantees the sealing performance.
[0052] In this embodiment, the bushing unit 21 is provided with a limiting part 22 on the inner peripheral wall of the journal unit 12 of the cross shaft assembly 10; one end of the second skeleton part 322 is connected to the first skeleton part 321; the other end of the second skeleton part 322 abuts against the limiting part 22.
[0053] Understandably, the bushing assembly 20 includes a bushing unit 21 and a limiting part 22. The limiting groove and the limiting part 22 are provided on the inner peripheral wall of the bushing unit 21 facing the journal unit 12. The other end of the second skeleton part 322 is located in the limiting groove and abuts against the limiting part 22. The limiting part 22 ensures that the sealing assembly 30 and the elastic assembly 40 abutting against it are precisely limited in the axial direction, preventing the entire assembly from axially moving within the receiving cavity, and ensuring the accuracy and consistency of the preload application.
[0054] For example, the skeleton unit 32 further includes a reinforcing part; the reinforcing part is supported at the connection between the first skeleton part 321 and the second skeleton part 322.
[0055] Understandably, the reinforcement can enhance the mechanical strength of the skeleton unit 32 at the connection point where the stress is greatest, prevent the skeleton unit 32 from deforming or fatigue fracture under long-term exposure to the thrust of the elastic component 40 and the reaction force of the bushing unit 21, and improve the durability of the sealing component 30 and the service life of the universal joint.
[0056] In this embodiment, the bushing unit 21 is provided with a first lubrication groove 23; the first lubrication groove 23 is in communication with the receiving cavity; the cage unit 61 covers the first lubrication groove 23 by the projection of the journal unit 12 of the cross shaft assembly 10 along the axial direction.
[0057] For example, the bushing unit 21 has a boss portion along the first direction, and the cage unit 61 abuts against the boss portion. The boss portion has a connecting groove along the radial direction of the bushing unit 21, which communicates with the first lubrication groove 23. Lubricating oil or grease can be impregnated into the connecting groove from the receiving cavity or other places, and then flow into the first lubrication groove 23 through the connecting groove, which plays a lubricating role for the movement of the cage unit 61 and reduces the friction between the cage unit 61 and the bushing unit 21. The projection of the cage unit 61 along the axial direction of the journal unit 12 of the cross shaft assembly 10 covering the first lubrication groove 23 can ensure that the cage unit 61 is fully lubricated, and at the same time prevent impurities from falling directly into the first lubrication groove 23.
[0058] In this embodiment, the cage unit 61 is provided with a second lubrication groove 63; the second lubrication groove 63 is connected to the receiving cavity and the first lubrication groove 23 respectively.
[0059] Please refer to Figure 3 and Figure 4 Understandably, the grease can be smoothly guided from the first lubrication groove 23 on the bushing unit 21 through the second lubrication groove 63 on the cage unit 61 to the working contact surface of the rolling assembly 50, thus achieving precise and efficient lubrication of the core friction pair.
[0060] Those skilled in the art will understand that the above embodiments are specific examples of implementing this disclosure, and in practical applications, various changes can be made in form and detail without departing from the scope of this disclosure.
Claims
1. A conical rolling element universal joint, characterized in that, The conical rolling element universal joint includes: cross shaft assembly; A bushing unit is fitted onto the cross shaft assembly; A sealing assembly is located between the bushing unit and the cross shaft assembly and is sleeved on the cross shaft assembly; the sealing assembly, the bushing unit, and the cross shaft assembly together form a receiving cavity; A cage unit is fitted onto the cross shaft assembly and located at the end of the receiving cavity away from the sealing assembly; Multiple rolling assemblies, the diameter of which gradually increases along a first direction; the multiple rolling assemblies are disposed within the receiving cavity and spaced apart circumferentially along the cross shaft assembly; wherein, the cage unit is provided with a plurality of retaining grooves spaced apart circumferentially along the cross shaft assembly; the small-diameter end of the rolling assembly is located within the retaining groove and abuts against the cage unit; An elastic component is located within the receiving cavity and between the sealing component and the rolling component; the elastic component is sleeved on the cross shaft assembly; wherein the large-diameter end of the rolling component abuts against the elastic component; the interaction force between the rolling component and the elastic component is greater than zero; the sealing component includes a sealing unit and a skeleton unit; the sealing unit is sleeved on the cross shaft assembly and abuts against at least a portion of the elastic component; the skeleton unit includes an integrally formed first skeleton portion and a second skeleton portion; the first skeleton portion is embedded in the sealing unit along a second direction; a portion of the second skeleton portion is embedded in the sealing unit along the first direction; wherein one end of the second skeleton portion is connected to the first skeleton portion; the other end of the second skeleton portion extends along the first direction and abuts against the bushing unit; the first direction and the second direction are perpendicular to each other.
2. A conical rolling element universal joint according to claim 1, characterized in that, The skeleton unit further includes a reinforcing part; the reinforcing part is supported at the connection between the first skeleton part and the second skeleton part.
3. A conical rolling element universal joint according to claim 1, characterized in that, The bushing unit has a limiting part on its inner peripheral wall facing the cross shaft assembly; one end of the second skeleton part is connected to the first skeleton part; the other end of the second skeleton part abuts against the limiting part.
4. A conical rolling element universal joint according to claim 1, characterized in that, At least a portion of the elastic component abuts against the sealing unit on the side away from the rolling component; wherein the projection of the abutment point between the elastic component and the sealing unit along the first direction covers the second skeleton portion.
5. A conical rolling element universal joint according to claim 1, characterized in that, The large-diameter end of the rolling assembly contacts the outer peripheral wall of the cross shaft assembly and the inner peripheral wall of the bushing unit.
6. A conical rolling element universal joint according to claim 4, characterized in that, The outer peripheral side of the small diameter end of the rolling assembly has a gap with the outer peripheral wall of the cross shaft assembly and the inner peripheral wall of the bushing unit.
7. A conical rolling element universal joint according to claim 1, characterized in that, The bushing unit is provided with a first lubrication groove; the first lubrication groove is in communication with the receiving cavity; the projection of the retainer unit along the axial direction of the cross shaft assembly covers the first lubrication groove.
8. A conical rolling element universal joint according to claim 7, characterized in that, The cage unit is provided with a second lubrication groove; the second lubrication groove is connected to the receiving cavity and the first lubrication groove respectively.
9. A conical rolling element universal joint according to claim 1, characterized in that, One side of the retainer unit has a gap with the outer peripheral wall of the cross shaft assembly; the opposite side of the retainer unit is in contact with the inner peripheral wall of the bushing unit.