Large-swing-angle constant-speed universal joint

Abstract

The utility model relates to the field of universal joints, and discloses a universal joint with a large swing angle and a constant speed. The device comprises a star-shaped sleeve, a plurality of inner grooves are formed in the peripheral wall of the star-shaped sleeve at intervals, each inner groove comprises an arc-shaped groove and a slope arc-shaped groove which are communicated with each other, and the depth of the end, away from the slope arc-shaped groove, of each arc-shaped groove is larger than that of the end, close to the slope arc-shaped groove, of each arc-shaped groove. The depth of one end, away from the slope arc groove, of the arc groove is larger than that of one end, away from the arc groove, of the slope arc groove, and a graphite powder coating is arranged on the surface of the slope arc groove. The arc-shaped groove and the slope arc-shaped groove form two sections of grooves with different depths, and the shallow sections of the grooves enable the steel balls to adjust positions more freely when the universal joint swings by reducing radial constraint on the steel balls and increasing force arms of contact points, so that a larger swinging angle is realized; meanwhile, abrasion of the star-shaped sleeve is relieved, and the service life of the star-shaped sleeve is prolonged.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of universal joint, specifically, relates to a large swing angle constant velocity universal joint. BACKGROUND

[0002] Ball cage type universal joint is also called constant velocity universal joint, and is an important component in a transmission system. The ball cage type universal joint comprises a bell type shell, a star type sleeve, a retainer and a plurality of steel balls. The star type sleeve is provided with inner raceways in the same number as the steel balls in circumferential intervals. The steel balls move in the inner raceways, and the inner raceways determine the movement track and contact characteristics of the steel balls. The star type sleeve is connected with a transmission shaft so that the transmission shaft can rotate at a certain angle relative to the bell type shell.

[0003] If the inner raceway is shallow, the steel balls are easy to fall out. Therefore, the existing inner raceway is an arc-shaped raceway, and the depths of the arc-shaped raceway at different positions are the same. However, during the swinging of the star type sleeve relative to the bell type shell, the depths of the arc-shaped raceway at different positions are the same, so the movement of the steel balls is strictly limited in the inner raceway, the contact point is close to the bottom of the inner raceway, the lateral constraint is strong, and the swing angle of the star type sleeve is relatively small. SUMMARY

[0004] To solve at least one aspect of the above problems, the utility model provides a large swing angle constant velocity universal joint, which comprises a star type sleeve, a plurality of inner grooves are arranged on the outer circumferential wall of the star type sleeve at intervals, the inner grooves comprise arc-shaped grooves and inclined arc grooves which are connected with each other, the depth of one end of the arc-shaped groove away from the inclined arc groove is greater than the depth of one end of the arc-shaped groove close to the inclined arc groove, the depth of one end of the inclined arc groove close to the arc-shaped groove is less than the depth of one end of the inclined arc groove away from the arc-shaped groove, the depth of one end of the arc-shaped groove away from the inclined arc groove is greater than the depth of one end of the inclined arc groove away from the arc-shaped groove, and a graphite powder coating is arranged on the surface of the inclined arc groove.

[0005] Optionally, the angle between the inclined arc groove and the tangent line at one end of the arc-shaped groove close to the inclined arc groove is 1-5 degrees.

[0006] Optionally, the length of the inclined arc groove in the axial direction of the star type sleeve is 0.6 times the length of the arc-shaped groove in the axial direction of the star type sleeve.

[0007] Optionally, one end of the star type sleeve is provided with an oil injection channel, the oil injection channel is located between two adjacent inner grooves, and oil outlets which are in communication with the oil injection channel are formed in the groove walls of two adjacent inclined arc grooves.

[0008] Optionally, the large swing angle constant velocity universal joint further comprises a bell-shaped cover and a plurality of steel balls, the number of the steel balls is the same as and corresponds to the number of the inner grooves, the star-shaped sleeve and the plurality of steel balls are installed in the bell-shaped cover, and the star-shaped sleeve is close to one end of the beveled arc groove and faces the inside of the bell-shaped cover.

[0009] Optionally, the large swing angle constant velocity universal joint further comprises a retainer, the retainer is sleeved on the star-shaped sleeve, and the plurality of steel balls are positioned and arranged by the retainer.

[0010] Optionally, the bell-shaped cover is provided with an installation groove at one end, and the star-shaped sleeve, the retainer and the plurality of steel balls are installed in the installation groove.

[0011] Optionally, a plurality of outer grooves are circumferentially formed on the groove wall of the installation groove, the number of the outer grooves is consistent with and corresponds to the number of the inner grooves, and the two sides of the steel ball are located in the corresponding inner groove and outer groove.

[0012] Optionally, a ring groove is formed on the retainer, a polyurethane elastic gasket ring is sleeved in the ring groove, and the polyurethane elastic gasket ring is adapted to be in contact with the groove wall of the installation groove.

[0013] Optionally, a spline hole is formed on the star-shaped sleeve.

[0014] Compared with the prior art, the beneficial technical effects of the utility model are as follows:

[0015] 1. The arc-shaped groove and the beveled arc groove form two grooves with different depths, the shallow section (i.e. the beveled arc groove) of the groove reduces the radial constraint on the steel ball and increases the force arm of the contact point, so that the steel ball can adjust the position more freely when the universal joint swings, thereby realizing a larger swing angle.

[0016] 2. Compared with setting the beveled arc groove as a groove tangent to the arc-shaped groove and horizontal, the beveled arc-shaped groove can make the depth of the groove slightly deeper, on the one hand, the contact stress received by the star-shaped sleeve is not too concentrated, the wear is slowed down, and the service life of the star-shaped sleeve is improved, on the other hand, the steel ball can be offset further outward along the shallow groove, thereby allowing a larger angle change without leaving the track.

[0017] 3. The graphite powder coating can make the lubrication effect at the beveled arc groove better, can increase the lubrication effect when the steel ball moves at the beveled arc groove, and effectively slow down the wear at the beveled arc groove of the star-shaped sleeve.

[0018] 4. Since the beveled arc groove is located inside the bell-shaped cover, the setting of the oil injection channel can facilitate the subsequent lubricating oil to directly reach the beveled arc groove, thereby reducing the waste of lubricating oil. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 The exploded view of the star-shaped sleeve, the bell-shaped cover and the retainer in the embodiment one of the utility model;

[0020] Figure 2 The sectional view of the star-shaped sleeve, the bell-shaped cover, the steel ball and the retainer in the embodiment one of the utility model;

[0021] Figure 3 The sectional view of the star-shaped sleeve in the embodiment one of the utility model;

[0022] Figure 4 The structural view of the star-shaped sleeve in the embodiment two of the utility model;

[0023] Figure 5 The exploded view of the retainer and the polyurethane elastic gasket ring in the embodiment two of the utility model.

[0024] The figure mark explanation: 1, star-shaped sleeve;11, inner groove;12, arc-shaped groove;13, inclined arc-shaped groove;14, spline hole;15, oil injection channel;16, oil outlet;2, bell-shaped cover;21, installation groove;22, outer groove;3, steel ball;4, retainer;41, polyurethane elastic gasket ring. Specific implementation

[0025] In order to make the above purpose, features and advantages of the utility model more obvious and easy to understand, the following is combined with the attached Figures 1-5 The application is further described in detail.

[0026] The embodiment of the utility model provides a large swing angle constant speed universal joint, embodiment one: refer to Figure 1 With Figure 2 The large swing angle constant speed universal joint includes star-shaped sleeve 1, bell-shaped cover 2, steel ball 3 and retainer 4. The outer peripheral wall of star-shaped sleeve 1 is evenly provided with a plurality of inner grooves 11, and the number of steel balls 3 is same as the number of inner grooves 11 and one-to-one correspondence. Retainer 4 is sleeved on star-shaped sleeve 1 and synchronously operates with star-shaped sleeve 1, and a plurality of steel balls 3 are evenly spaced and positioned by retainer 4. Star-shaped sleeve 1, a plurality of steel balls 3 and retainer 4 are installed in bell-shaped cover 2, and star-shaped sleeve 1 can swing within a certain angle range relative to bell-shaped cover 2 through the cooperation of a plurality of steel balls 3 and inner grooves 11. Wherein, the inner groove 11 includes the arc-shaped groove 12 and the inclined arc-shaped groove 13 which are interconnected and different in depth, thereby being able to increase the swing angle of star-shaped sleeve 1 and also being able to slow down the wear of star-shaped sleeve 1.

[0027] Combined Figure 1 Refer to Figure 2 With Figure 3The depth of the inner groove 11 mentioned in the embodiment refers to the length of the inner groove 11 in the radial direction of the star sleeve 1. The arc-shaped groove 12 and the inclined arc-shaped groove 13 are arranged in the axial direction of the star sleeve 1, and the axial direction of the star sleeve 1 is the length direction of the arc-shaped groove 12 and the inclined arc-shaped groove 13. The arc-shaped groove 12 is through the star sleeve 1 away from the inclined arc-shaped groove 13, and the inclined arc-shaped groove 13 is through the star sleeve 1 away from the arc-shaped groove 12.

[0028] The depth of the end of the arc-shaped groove 12 away from the inclined arc-shaped groove 13 is greater than the depth of the end of the arc-shaped groove 12 close to the inclined arc-shaped groove 13; the depth of the end of the arc-shaped groove 12 away from the inclined arc-shaped groove 13 is greater than the depth of the end of the inclined arc-shaped groove 13 away from the arc-shaped groove 12, and the end of the star sleeve 1 close to the inclined arc-shaped groove 13 faces the inside of the bell-shaped cover 2. In this way, when the star sleeve 1 swings relative to the bell-shaped cover 2, part of the steel balls 3 will move to the inclined arc-shaped groove 13, and then due to the depth of the inclined arc-shaped groove 13 being smaller than the depth of the arc-shaped groove 12, the radial constraint force on the steel balls 3 located in the inclined arc-shaped groove 13 is smaller, so that the steel balls 3 have a larger radial movement space in the inclined arc-shaped groove 13, the contact point is closer to the edge of the inclined arc-shaped groove 13, allowing the steel balls 3 to adjust the position at a larger angle, thereby increasing the angle of swing of the star sleeve 1.

[0029] In combination with Figure 1 Referring to Figure 2 With Figure 3 If the inclined arc-shaped groove 13 is a groove tangent to the arc-shaped groove 12 and parallel to the axis of the star sleeve 1 in the horizontal direction, then the contact stress at the inclined arc-shaped groove 13 will be more concentrated, which will accelerate the wear of the bottom of the inclined arc-shaped groove 13. Therefore, the inclined arc-shaped groove 13 is arranged in an inclined state, that is, the depth of the end of the inclined arc-shaped groove 13 close to the arc-shaped groove 12 is slightly smaller than the depth of the end of the inclined arc-shaped groove 13 away from the arc-shaped groove 12, which can make the depth of the inclined arc-shaped groove 13 relatively deeper, so that part of the contact stress can be dispersed to the groove wall of the inclined arc-shaped groove 13, thereby slowing down the wear. At the same time, the steel balls 3 are not easy to come out of the inclined arc-shaped groove 13 at a larger angle change.

[0030] In combination with Figure 1 Referring to Figure 2 With Figure 3 In the embodiment, the included angle between the bottom of the inclined arc-shaped groove 13 and the tangent line between the bottom of the arc-shaped groove 12 close to the inclined arc-shaped groove 13 is X, and 1°≤X≤5°, preferably X is 4.7°, which can not only increase the swing angle of the star sleeve 1, but also slow down the wear of the bottom of the inclined arc-shaped groove 13, thereby prolonging the service life of the star sleeve 1, and the steel balls 3 are not easy to come out of the inclined arc-shaped groove 13 at the maximum swing angle.

[0031] The length of the inclined arc groove 13 along the axial direction of the star-shaped sleeve 1 is 0.6 times the length of the arc groove 12 along the axial direction of the star-shaped sleeve 1. Therefore, when the star-shaped sleeve 1 swings, some of the steel balls 3 can roll into the arc groove 12 in time. Since the arc groove 12 is relatively deep, it can better constrain the steel balls 3, thereby enabling the cage 4 to better constrain the remaining steel balls 3, making the entire star-shaped sleeve 1 more stable after swinging.

[0032] The bottom and walls of the inclined arc groove 13 are coated with graphite powder, which increases the lubrication effect of the steel ball 3 when it moves in the inclined arc groove 13, and effectively reduces the wear of the star sleeve 1 in the inclined arc groove 13.

[0033] Combination Figure 1 Reference Figure 2 and Figure 3 One end of the bell-shaped cover 2 has a mounting groove 21, in which the star-shaped sleeve 1, the retainer 4, and multiple steel columns are installed. The mounting groove 21 has multiple outer grooves 22 circumferentially oriented, the number of which corresponds to the number of inner grooves 11. The two sides of the steel ball 3 are located in the corresponding inner grooves 11 and outer grooves 22, respectively. The inner grooves 11 and outer grooves 22 work together to act as a track for the movement of the steel ball 3. Simultaneously, when the bell-shaped cover 2 rotates, the interaction between the steel ball 3 and the inner grooves 11 and outer grooves 22 drives the star-shaped sleeve 1 to rotate synchronously.

[0034] The star-shaped sleeve 1 has a spline hole 14 that passes through it. The drive shaft that needs to cooperate with the universal joint can be inserted into the spline hole 14 to achieve synchronous rotation with the star-shaped sleeve 1.

[0035] The implementation principle of a universal joint with a large swing angle and constant velocity according to an embodiment of this application is as follows: the arc-shaped groove 12 and the inclined arc-shaped groove 13 form two grooves of different depths. The shallow section of the groove (i.e., the inclined arc-shaped groove 13) reduces the radial constraint on the steel ball 3 and increases the lever arm of the contact point, allowing the steel ball 3 to adjust its position more freely during the swing of the universal joint, thereby achieving a larger swing angle. In addition, compared to setting the inclined arc-shaped groove 13 as a groove tangent to and horizontal to the arc-shaped groove 12, the inclined arc-shaped groove 12 allows the groove depth of this section to be slightly deeper. On the one hand, this prevents the contact stress on the star-shaped sleeve 1 from being too concentrated, reducing wear and improving the life of the star-shaped sleeve 1. On the other hand, the steel ball 3 can be offset further outward along the shallow groove, thereby allowing for a larger angle change without derailing.

[0036] Example 2, combined with Figure 1 Reference Figure 2 and Figure 3The difference between this embodiment and the previous embodiment is that: the star-shaped sleeve 1 has multiple oil injection channels 15 at the end away from the bottom of the mounting groove 21, each oil injection channel 15 is located between two adjacent inner grooves 11, and the oil injection channel 15 does not penetrate the star-shaped sleeve 1 along its own opening direction. The retainer 4 has an annular groove, and a polyurethane elastic gasket ring 41 is fitted inside the annular groove. The polyurethane elastic gasket ring 41 is adapted to contact the groove wall of the mounting groove 21.

[0037] Since the end of the star-shaped sleeve 1 closest to the inclined arc groove 13 faces the bottom of the mounting groove 21, adding lubricating oil is inconvenient. Therefore, by setting up an oil injection channel 15, the convenience of injecting lubricating oil into the inclined arc groove 13 can be improved. Multiple oil injection channels 15 have the same structure; the following description uses the structure of one oil injection channel 15 as an example.

[0038] Combination Figure 2 Reference Figure 4 and Figure 5 Figure 2 Figure 4 Figure 5 Each of the two adjacent inclined arc grooves 13 has an oil outlet 16 connected to the oil injection channel 15. Since the oil outlet 16 is located on the wall of the inclined arc groove 13, when a syringe or other oil injection tube is inserted into the uppermost oil injection channel 15 to inject lubricating oil, the lubricating oil will flow along the wall of the inclined arc groove 13 to the bottom of the inclined arc groove 13. Since the bottom of the inclined arc groove 13 is inclined, the lubricating oil will flow along the slope after reaching the bottom of the inclined arc groove 13, thereby coating the entire wall and bottom of the inclined arc groove 13 with lubricating oil, further improving the lubrication of the inclined arc groove 13.

[0039] The polyurethane elastic gasket ring 41 transforms the rigid contact between the retainer 4 and the bell-shaped housing 2 during the swing of the star-shaped sleeve 1 into a flexible contact, reducing noise generated when the retainer 4 and the bell-shaped housing 2 come into contact during the swing of the star-shaped sleeve 1. In addition, the polyurethane elastic gasket ring 41 has high wear resistance, thus its service life is relatively long.

[0040] In the description of this disclosure, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this disclosure and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this disclosure.

[0041] In the description of this disclosure, "multiple" means at least two, such as two, three, etc., unless otherwise expressly and specifically limited.

[0042] In this disclosure, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this disclosure according to the specific circumstances.

[0043] In this disclosure, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0044] It should be noted that when a component is referred to as "fixed to," "set on," "fixed to," or "mounted on" another component, it can be directly on the other component or there may be an intervening component. When a component is considered to be "connected to another component," it can be directly connected to the other component or there may be an intervening component. Furthermore, when a component is considered to be "fixedly connected" to another component, the connection can be detachable or non-detachable, such as through socketing, snap-fitting, integral molding, welding, etc., which are achievable in conventional technologies and will not be elaborated upon here.

[0045] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0046] The above embodiments are merely illustrative of several implementation methods of this disclosure, and their descriptions are relatively specific and detailed. However, they should not be construed as limiting the scope of the utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the inventive concept of this disclosure, and these modifications and improvements all fall within the protection scope of this disclosure.

Claims

1. A universal joint with a large swing angle and constant velocity, characterized in that: The system includes a star-shaped sleeve (1), the outer peripheral wall of which is provided with a plurality of inner grooves (11) spaced apart. The inner grooves (11) include interconnected arc-shaped grooves (12) and inclined arc-shaped grooves (13). The depth of the end of the arc-shaped groove (12) away from the inclined arc-shaped groove (13) is greater than the depth of the end of the arc-shaped groove (12) near the inclined arc-shaped groove (13). The depth of the end of the inclined arc-shaped groove (13) near the arc-shaped groove (12) is less than the depth of the end of the inclined arc-shaped groove (13) away from the arc-shaped groove (12). The depth of the end of the arc-shaped groove (12) away from the inclined arc-shaped groove (13) is greater than the depth of the end of the inclined arc-shaped groove (13) away from the arc-shaped groove (12). The surface of the inclined arc-shaped groove (13) is provided with a graphite powder coating.

2. The universal joint with large swing angle and constant velocity according to claim 1, characterized in that: The angle between the inclined arc groove (13) and the tangent of the arc groove (12) near the end of the inclined arc groove (13) is 1°-5°.

3. The universal joint with large swing angle and constant velocity according to claim 1, characterized in that: The length of the inclined arc groove (13) along the axial direction of the star sleeve (1) is 0.6 times the length of the arc groove (12) along the axial direction of the star sleeve (1).

4. The universal joint with large swing angle and constant velocity according to claim 1, characterized in that: One end of the star-shaped sleeve (1) is provided with an oil injection channel (15), which is located between two adjacent inner grooves (11). The groove walls of the two adjacent inclined arc grooves (13) are provided with oil outlets (16) that communicate with the oil injection channel (15).

5. The universal joint with large swing angle and constant velocity according to claim 1, characterized in that: It also includes a bell-shaped cover (2) and a plurality of steel balls (3), the number of steel balls (3) being the same as the number of inner grooves (11) and corresponding one-to-one. The star-shaped sleeve (1) and the plurality of steel balls (3) are all installed inside the bell-shaped cover (2), and the end of the star-shaped sleeve (1) near the inclined arc groove (13) faces the inside of the bell-shaped cover (2).

6. The universal joint with large swing angle and constant velocity according to claim 5, characterized in that: It also includes a retainer (4), which is sleeved on the star-shaped sleeve (1), and the multiple steel balls (3) are positioned and arranged through the retainer (4).

7. The universal joint with large swing angle and constant velocity according to claim 6, characterized in that: The bell-shaped cover (2) has an installation groove (21) at one end, and the star-shaped sleeve (1), the retainer (4) and the multiple steel balls (3) are all installed in the installation groove (21).

8. The universal joint with large swing angle and constant velocity according to claim 7, characterized in that: The mounting groove (21) has multiple outer grooves (22) circumferentially opened on the groove wall. The number of outer grooves (22) is the same as the number of inner grooves (11) and they correspond one-to-one. The two sides of the steel ball (3) are located in the corresponding inner grooves (11) and outer grooves (22) respectively.

9. The universal joint with large swing angle and constant velocity according to claim 7, characterized in that: The retainer (4) has an annular groove, and a polyurethane elastic pad ring (41) is fitted inside the annular groove. The polyurethane elastic pad ring (41) is adapted to contact the groove wall of the mounting groove (21).

10. The universal joint with large swing angle and constant velocity according to claim 1, characterized in that: The star-shaped sleeve (1) has a spline hole (14).

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