Lightweight end tooth structure universal joint easy to align teeth

Abstract

The utility model relates to the technical field of universal joint connection, and discloses a light-weight end tooth structure universal joint easy to align teeth, which comprises a rotation axis of the universal joint and an end tooth disc rotating around the rotation axis of the universal joint, a plurality of tooth parts are arranged on the end tooth disc along the rotation axis in a central symmetry manner, and the tooth parts are arranged on the end tooth disc. The tooth part comprises a tooth bottom arranged on the end-toothed disc, a tooth top is arranged at the top of the tooth bottom, symmetrical first tooth surfaces are arranged at the two opposite side ends of the tooth bottom, and symmetrical second tooth surfaces are arranged at the two opposite side ends of the tooth top. The second angle formed by the two second tooth surfaces on the tooth top is configured to be larger than the first angle formed by the two first tooth surfaces on the tooth bottom, the meshing tolerance range between the tooth parts is enlarged through the design, larger tooth alignment tolerance is allowed in the assembling process, and therefore the axial alignment operation of the gear and a matched piece is simplified, and the assembling efficiency is improved. And the adjustment frequency during assembly is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of universal joint connections, in particular to a universal joint with an end-tooth structure which is lightweight and easy to align teeth. Background Art

[0002] In traditional wheel hub and universal joint connections, internal and external splines are the dominant method. This means that precise (external) or (internal) splines must be machined at the universal joint end, increasing manufacturing complexity and cost. However, the demand for high torque transmission necessitates a thicker spline design, which inevitably increases component weight. This weight disadvantage makes this structure difficult to meet the stringent lightweight component requirements of new energy vehicles. To address the shortcomings of traditional splines, the industry is widely adopting Hirth-type end face gearing (or improved Hirth gearing) as an alternative. This design shifts the meshing surface from the radial direction (spline) to the end face, machining a precise tooth profile on the universal joint end face. This end-to-end face meshing method significantly simplifies the structure and effectively reduces component weight while maintaining the same or even higher torque capacity, making it an ideal choice for meeting the lightweight goals of new energy vehicles.

[0003] Chinese patent document CN101132934A discloses a hub / universal joint assembly with end teeth. While the proposed end-face tooth scheme achieves gapless meshing and overload protection through a specific tooth face angle of 20°-30° and optimized root / tip radius R>r, it still suffers from the following drawbacks: 1. Insufficient lightweighting: Structural innovations have not been made to reduce tooth weight, and the rounded tip / root design increases local material thickness, contradicting the extreme lightweight requirements of new energy vehicles. 2. The tooth top position is still relatively weak. 3. The self-aligning function is missing, relying on the tooth face angle for "self-centering" but lacking an integrated active guide structure. Assembly still requires manual precision alignment of the teeth, resulting in low efficiency. Therefore, this solution does not meet existing requirements. Therefore, we propose a lightweight and easy-to-align end-tooth universal joint. Utility Model Content

[0004] The utility model provides a lightweight and easy-to-align end-tooth structure universal joint with an embedded self-aligning gear mechanism, which has the beneficial effects of lighter, faster and more reliable connection, and solves the problems mentioned in the above background technology.

[0005] The utility model provides the following technical solutions: a universal joint with a lightweight and easy-to-align end-tooth structure, comprising a rotation axis of the universal joint and an end toothed disc rotating around the rotation axis of the universal joint, wherein the end toothed disc is provided with a plurality of tooth portions in a centrally symmetrical shape along the rotation axis, the tooth portion comprising a tooth bottom provided on the end toothed disc, a tooth top provided on the top of the tooth bottom, first tooth surfaces in a symmetrical shape provided at two opposite side ends of the tooth bottom, and second tooth surfaces in a symmetrical shape provided at two opposite side ends of the tooth top, an intersection angle between the extended surfaces of the two first tooth surfaces being a first angle, an intersection angle between the two second tooth surfaces being a second angle, an angle of the second angle being greater than the first angle, and a maximum angle of the second angle being less than 10 times the first angle.

[0006] In the present invention, the second angle formed by the two second tooth surfaces on the tooth top is configured to be greater than the first angle formed by the two first tooth surfaces on the tooth bottom. This design expands the meshing tolerance range between the teeth and allows a larger tooth tolerance during assembly, thereby simplifying the axial alignment operation of the gear and the mating part and reducing the number of adjustments during assembly.

[0007] As an optional solution for a lightweight and easy-to-align end tooth structure universal joint described in the utility model, the pressure angle of the first tooth surface is 15°~45°, the pressure angle of the second tooth surface is 15°~65°, and the difference between the pressure angle of the second tooth surface and the pressure angle of the first tooth surface is 0.1°~20°.

[0008] As an optional solution for a lightweight and easy-to-align end tooth structure universal joint described in the utility model, the connection between the tooth bottom and the tooth top is the tooth waist, and a connecting surface is provided between the tooth bottom and the tooth top near the tooth waist.

[0009] As an optional solution of the light-weight and easy-to-align end tooth structure universal joint described in the utility model, the maximum vertical height between the tooth top and the end tooth disc is , and the maximum vertical height between the tooth waist and the end gear disc on the same circumference is ,in, .

[0010] As an optional solution for a lightweight and easy-to-align end tooth structure universal joint described in the utility model, the end surface structure of the connecting surface is a curved surface structure, and the top of the tooth top is provided with a chamfered corner.

[0011] As an optional solution for a lightweight and easy-to-align end tooth structure universal joint described in the utility model, a large circle and a small circle are provided along the rotation axis as the center of the circle, which are located in the same horizontal plane as the bottom surface of the end gear disc, and the radius of the large circle is not less than 1.5 times the radius of the small circle. The front and rear ends of the tooth portion are respectively provided with a first end face located on the large circle and a second end face located on the small circle.

[0012] As an optional solution for a lightweight and easy-to-align end tooth structure universal joint described in the utility model, the intersection of the two first tooth surfaces and the end gear disc on the tooth bottom is two first intersection lines, the intersection of the two first tooth surfaces and the tooth waist on the tooth bottom is two second intersection lines, and the top of the tooth top is located at the intersection between the two second tooth surfaces as a third intersection line.

[0013] As an optional solution for a lightweight and easy-to-align end tooth structure universal joint described in the present invention, the two first intersection lines, the two second intersection lines and the extension lines of the third intersection line intersect, and the intersection point is the fourth point, and the fourth point is located on the rotation axis.

[0014] The utility model has the following beneficial effects:

[0015] 1. This weight-saving universal joint is connected to the gear plate, and the second angle formed by the two second tooth surfaces is configured to be greater than the first angle formed by the two first tooth surfaces. This design expands the meshing tolerance range between the teeth, allowing for a larger tooth alignment tolerance during assembly, thereby simplifying the axial alignment operation of the gear and the mating part and reducing the number of adjustments during assembly.

[0016] 2. This weight-saving universal joint is connected to the geared disc. Unlike the traditional face gear design in which the first tooth has only a single tooth flank, this design innovatively adopts a double-layer tooth flank structure, in which the first and second tooth flanks form the working contours of the tooth bottom and tooth top respectively. This double-layer configuration effectively reduces the weight of the tooth part by optimizing material distribution, thereby achieving lightweighting.

[0017] 3. This weight-saving universal joint is connected to the sprocket. The double-layer tooth side surface structure design not only reduces the overall weight of the end sprocket, but also enhances the geometric continuity of the upper part and top area of ​​the tooth through the tooth top, significantly improving the bending strength and fatigue life of the tooth top, ensuring reliability under high load conditions.

[0018] 4. This type of weight-saving universal joint is connected to the self-aligning gear plate. Through the unique geometric design of the teeth, the device can significantly reduce weight. At the same time, through the coordination of the tooth bottom and tooth top, the self-aligning mechanism is embedded, and the tooth top area is fundamentally strengthened to ensure that even under the most demanding bolt pre-tightening conditions, the risk of collision is completely avoided, achieving a lighter, faster and more reliable connection. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic diagram of the three-dimensional structure of a universal joint with an end-tooth structure that is lightweight and easy to align teeth according to the present invention;

[0020] Figure 2 This is a perspective view of a universal joint with a lightweight and easy-to-align end-tooth structure according to the present invention;

[0021] Figure 3 This is a schematic diagram of the three-dimensional structure of the tooth portion of the present invention;

[0022] Figure 4 This is a schematic cross-sectional structural diagram of the tooth top of the present invention;

[0023] Figure 5 This is a schematic cross-sectional structural diagram of the tooth bottom of the present invention;

[0024] Figure 6 It is a schematic cross-sectional structural diagram of the tooth portion of the present invention.

[0025] In the figure: 1. end gear disc; 2. rotation axis; 20. large circumference; 21. small circumference; 3. tooth portion; 30. tooth bottom; 31. tooth top; 32. tooth waist; 33. first end face; 34. second end face; 300. first tooth surface; 301. first angle; 302. first intersection line; 303. second intersection line; 310. second tooth surface; 311. second angle; 312. third intersection line; 320. connecting surface; 4. fourth point. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0027] Example 1: This example aims to solve the problem of how to increase radial strength and achieve self-alignment. Figure 1 、 Figure 2 、 Figure 3 、 Figure 4 and Figure 5, a lightweight and easy-to-align end-tooth structure universal joint, including a rotation axis 2 of the universal joint and an end toothed disc 1 rotating around the rotation axis 2 of the universal joint, a plurality of tooth portions 3 are provided on the end toothed disc 1 in a centrally symmetrical shape along the rotation axis 2. The above is the existing technology, so no further details will be given. The tooth portion 3 includes a tooth bottom 30 provided on the end toothed disc 1, a tooth top 31 is provided on the top of the tooth bottom 30, and a tooth waist 32 is connected between the tooth bottom 30 and the tooth top 31. A connecting surface 320 is provided between the tooth bottom 30 and the tooth top 31 near the tooth waist 32. This design innovatively adopts a double tooth side surface structure and adds a tooth waist 32 structure. In the tooth waist 32 area, that is, at the connecting surface 320, the equivalent stress is 40%-60% lower than that of the tooth top 31 / tooth bottom 30. The end face structure of the connecting surface 320 is a curved surface structure, and the top of the tooth top 31 is provided with a chamfer. The top of the tooth top 31 is chamfered, and the connecting surface 320 between the tooth bottom 30 and the tooth top 31 at the tooth waist 32 is set to a curved surface, so that it can rotate more smoothly when the gears are engaged, thereby reducing jamming.

[0028] In this embodiment, the tooth portion 3 is composed of a double-layer structure of a tooth bottom 30 and a tooth top 31 , and the strength of the tooth portion 3 is enhanced by increasing the thickness of the tooth waist 32 .

[0029] It should be noted that the non-curved tooth waist 32 and the non-rounded tooth top 31 can still be directly used as a weight-saving universal joint connecting the self-aligning gear disc connection structure.

[0030] Example 2: This example aims to solve the problem of how to reduce the weight of the tooth part, realize self-alignment, and reduce the difficulty of assembly. This example is an improvement made on the basis of Example 1. For details, please refer to Figure 1 、 Figure 2 、 Figure 3 、 Figure 4 、 Figure 5 and Figure 6 The connection between the tooth bottom 30 and the tooth top 31 is the tooth waist 32, and the maximum vertical height between the tooth top 31 and the end gear disc 1 is , and the maximum vertical height between the tooth waist 32 and the end gear disc 1 on the same circumference is ,in, The two opposite side ends of the tooth bottom 30 are provided with symmetrical first tooth surfaces 300, and the two opposite side ends of the tooth top 31 are provided with symmetrical second tooth surfaces 310. The intersection angle between the extended surfaces of the two first tooth surfaces 300 is a first angle 301, and the intersection angle between the two second tooth surfaces 310 is a second angle 311. The angle of the second angle 311 is greater than the first angle 301, and the maximum angle of the second angle 311 is less than 10 times the first angle 301. The pressure angle of the first tooth surface 300 is 15°~45°, the pressure angle of the second tooth surface 310 is 15°~65°, and the difference between the pressure angle of the second tooth surface 310 and the pressure angle of the first tooth surface 300 is 0.1°~20°.

[0031] In this embodiment, compared to the tooth portion 3 with a conventional single tooth flank design, the tooth portion 3 with a double-layer tooth flank structure has a tooth bottom 30 with a first tooth surface 300 and a tooth top 31 with a second tooth surface 310 with different inclination angles. This reduces the total weight of the self-aligning tooth by reducing the top material of the tooth top 31 and lowering the overall height. When the ratio of the first angle 301 to the second angle 311 is 1.5, the pressure angle difference is 15°. When the tooth portion 3 is reduced in weight by 10%, the height is reduced by 21%, and the thickness of the tooth top 31 at the same position is increased by 42%.

[0032] Moreover, the inclination angle of the second tooth surface 310 on the tooth top 31 is greater than that of the first tooth surface 300 on the tooth bottom 30. Due to its larger inclination angle, when at the same height as the tooth portion 3 designed with an ordinary single tooth side surface, the radial tooth thickness of the double-layer tooth side surface tooth portion 3 is significantly greater than that of the tooth portion 3 designed with a single tooth side surface, so it can withstand a greater axial preload during assembly, the tooth top 31 is less likely to deform, and the service life of the tooth portion 3 is significantly improved.

[0033] Example 3: This example aims to solve the problem of how to achieve self-aligning teeth and increase radial strength. This example is an improvement based on Example 1. For details, please refer to Figure 1 、 Figure 2 、 Figure 3 、 Figure 4 and Figure 5 A large circle 20 and a small circle 21 are provided along the rotation axis 2, which are located at the same horizontal plane as the bottom surface of the end gear disc 1. The radius of the large circle 20 is not less than 1.5 times the radius of the small circle 21. The front and rear ends of the tooth portion 3 are respectively provided with a first end face 33 located on the large circle 20 and a second end face 34 located on the small circle 21.

[0034] The intersection of the two first tooth surfaces 300 and the end gear disc 1 on the tooth bottom 30 is two first intersection lines 302, the intersection of the two first tooth surfaces 300 and the tooth waist 32 on the tooth bottom 30 is two second intersection lines 303, and the top of the tooth top 31 is located at the intersection between the two second tooth surfaces 310 as the third intersection line 312. The two first intersection lines 302, the two second intersection lines 303 and the extension line of the third intersection line 312 intersect, and their intersection point is the fourth point 4. The fourth point 4 is located on the rotation axis 2. The sizes of the tooth bottom 30 and the tooth top 31 gradually decrease in the direction toward the rotation axis 2.

[0035] In this embodiment: on the tooth portion 3, in the extension line of the first intersection line 302, the second intersection line 303 and the third intersection line 312 toward the fourth point 4, the second intersection line 303 is located between the first intersection line 302 and the third intersection line 312 in the axial and radial directions, until the first intersection line 302, the second intersection line 303 and the third intersection line 312 intersect. After the intersection, the three points coincide with the fourth point 4 of the rotation axis 2. At this time, the fourth point 4 and the end gear disc 1 are in the same plane, so that when meshing, the meshing object can be centered between the teeth 3 on the end gear disc 1 to reduce shaking.

[0036] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus.

[0037] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A lightweight and easy-to-align end-tooth structure universal joint, comprising a universal joint rotation axis (2) and an end tooth disc (1) rotating around the universal joint rotation axis (2), wherein the end tooth disc (1) is provided with a plurality of tooth portions (3) in a centrally symmetrical manner along the rotation axis (2), and is characterized in that: The tooth portion (3) comprises a tooth bottom (30) provided on the end tooth disc (1), and a tooth top (31) is provided on the top of the tooth bottom (30); Two opposite side ends of the tooth bottom (30) are provided with symmetrical first tooth surfaces (300), and two opposite side ends of the tooth top (31) are provided with symmetrical second tooth surfaces (310), the intersection angle between the extended surfaces of the two first tooth surfaces (300) is a first angle (301), and the intersection angle between the two second tooth surfaces (310) is a second angle (311), the angle of the second angle (311) is greater than the first angle (301), and the maximum angle of the second angle (311) is less than 10 times the first angle (301).

2. A lightweight and easy-to-align end-tooth structure universal joint according to claim 1, characterized in that: The pressure angle of the first tooth surface (300) is 15° to 45°, the pressure angle of the second tooth surface (310) is 15° to 65°, and the difference between the pressure angle of the second tooth surface (310) and the pressure angle of the first tooth surface (300) is 0.1° to 20°.

3. The lightweight and easy-to-align end-tooth structure universal joint according to claim 1, characterized in that: The connection between the tooth bottom (30) and the tooth top (31) is a tooth waist (32), and a connecting surface (320) is provided between the tooth bottom (30) and the tooth top (31) near the tooth waist (32).

4. The lightweight and easy-to-align end-tooth structure universal joint according to claim 3, characterized in that: The maximum vertical height between the tooth top (31) and the end gear disc (1) is , and the maximum vertical height between the tooth waist (32) and the end tooth disc (1) located on the same circumferential line is ,in, .

5. The lightweight and easy-to-align end-tooth structure universal joint according to claim 3, characterized in that: The end surface structure of the connecting surface (320) is a curved surface structure, and the top of the tooth top (31) is provided with a rounded corner.

6. The lightweight and easy-to-align end-tooth structure universal joint according to claim 1, characterized in that: A large circle (20) and a small circle (21) are provided along the rotation axis (2) and are located at the same horizontal plane as the bottom surface of the end toothed disc (1). The radius of the large circle (20) is not less than 1.5 times the radius of the small circle (21). The front and rear ends of the tooth portion (3) are respectively provided with a first end surface (33) located on the large circle (20) and a second end surface (34) located on the small circle (21).

7. The lightweight and easy-to-align end-tooth structure universal joint according to claim 3, characterized in that: The intersections between the two first tooth surfaces (300) and the end tooth disc (1) on the tooth bottom (30) are two first intersection lines (302), the intersections between the two first tooth surfaces (300) and the tooth waist (32) on the tooth bottom (30) are two second intersection lines (303), and the top of the tooth top (31) is located at the intersection between the two second tooth surfaces (310) as a third intersection line (312).

8. The lightweight and easy-to-align end-tooth structure universal joint according to claim 7, characterized in that: The two first intersection lines (302), the two second intersection lines (303) and the extension lines of the third intersection line (312) intersect, and the intersection point is a fourth point (4), and the fourth point (4) is located on the rotation axis (2).

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