Worm applied to automobile linear steering system

Abstract

The utility model relates to the technical field of automobile parts, in particular to a worm applied to an automobile linear steering system, which comprises a worm body, the worm body comprises a connecting section, a meshing section and a supporting section, the connecting section and the supporting section are coaxially connected to two ends of the meshing section respectively, and the diameter of the meshing section is larger than that of the supporting section and that of the connecting section. The meshing section is mainly used for being meshed with the worm gear, the diameter of the meshing section is larger than that of the connecting section and that of the supporting section, the structural strength of the meshing section is improved, the service life of the meshing section is prolonged, and then the service life of the worm body is prolonged.

Description

Technical Field

[0001] The present application relates to the technical field of automobile parts, and in particular to a worm gear used in an automobile linear steering system. Background Art

[0002] The automotive steer-by-wire system is an advanced steering technology that uses electronic signals to transmit the driver's steering instructions instead of traditional mechanical connections. This technology is of great significance in improving vehicle handling performance, energy conservation and emission reduction, and autonomous driving.

[0003] The worm gear in the automotive steer-by-wire system is usually used in conjunction with the motor and the electronic control unit (ECU) to accurately control the steering assist according to the vehicle's driving state and the driver's input. The worm gear converts the rotational motion of the steering wheel into the rotation of the worm gear by meshing with the worm gear. The worm gear is connected to the steering shaft. When the worm gear rotates, the steering shaft also moves, thereby controlling the steering of the vehicle. The meshing of the worm gear enables the rotational motion of the steering wheel to be converted into precise linear motion, ensuring that the vehicle can be accurately steered according to the driver's intention.

[0004] Therefore, in the automobile wire-controlled steering system, the worm plays a key role in converting the driver's rotation command into the actual steering action. The current steering worm has the problem of insufficient strength, which affects the service life of the worm. Utility Model Content

[0005] In order to improve the structural strength of the worm and increase the service life of the worm, the present application provides a worm applied to an automobile linear steering system.

[0006] The present application provides a worm gear for a linear steering system of an automobile, which adopts the following technical solution:

[0007] A worm gear used in a linear steering system of an automobile comprises a worm gear body, wherein the worm gear body comprises a connecting section, a meshing section and a supporting section, wherein the connecting section and the supporting section are coaxially connected to two ends of the meshing section respectively, and the diameter of the meshing section is larger than the diameters of the supporting section and the connecting section.

[0008] By adopting the above technical solution, the meshing section is mainly used to mesh with the worm wheel. The diameter of the meshing section is larger than the diameters of the connecting section and the supporting section, which helps to improve the structural strength of the meshing section, increase the service life of the meshing section, and thus increase the service life of the worm body.

[0009] Preferably, the connection points between the two ends of the meshing section and the connecting section and the supporting section are both provided with chamfers.

[0010] By adopting the above technical solution, chamfers are provided at the connections between the two ends of the meshing segment and the connecting segment and the supporting segment, which helps to improve the stress distribution at the two ends of the meshing segment, reduce the stress concentration phenomenon at the connections between the two ends of the meshing segment and the connecting segment and the supporting segment, reduce the structural stress at the two ends of the meshing segment, improve the structural strength of the worm body, and improve the service life of the worm body.

[0011] Preferably, the connection between the chamfer 1 and the connecting section or the supporting section is provided with a rounded corner 1.

[0012] By adopting the above technical solution, fillet one is connected with chamfer one, which further improves the stress distribution at the connection between the two ends of the meshing section and the connecting section and the supporting section, reduces the stress concentration phenomenon at the connection between the two ends of the meshing section and the connecting section and the supporting section, improves the structural strength of the worm body, and improves the service life of the worm body.

[0013] Preferably, the end of the connecting section away from the meshing section is coaxially connected with the first stage, the second stage, the third stage and the spline section in sequence, and the outer periphery of the spline section is provided with a plurality of spline grooves, which are evenly distributed circumferentially around the axis of the spline section.

[0014] By adopting the above technical solution and providing a spline segment, the connection between the worm body and the driving source is facilitated.

[0015] Preferably, the diameters of the first stage, the second stage and the third stage decrease successively along the axis of the connecting section in a direction away from the meshing section.

[0016] By adopting the above technical solution, the diameters of the first stage, the second stage and the third stage decrease successively along the axis of the connecting section in the direction away from the meshing section, which makes it convenient for the bearing to be sleeved on the second stage and abut against the side surface of the first stage close to the second stage. The diameter of the second stage is larger than that of the third stage, which facilitates the positioning of the connecting piece connecting the worm body and the driving source.

[0017] Preferably, the connection between the spline segment and the third stage is transitioned through an inclined surface.

[0018] By adopting the above technical solution, the connection between the spline segment and the third stage is transitioned through an inclined surface, which helps to improve the stress distribution between the third stage and the spline segment, reduce the stress concentration phenomenon at the connection between the spline segment and the third stage, reduce the possibility of fracture at the connection between the spline segment and the third stage, and increase the service life of the worm body.

[0019] Preferably, the distance from the bottom of the spline groove to the axis of the spline segment is smaller than the diameter of the third stage, and an oil storage tank is provided at one end of the third stage close to the spline segment, and the oil storage tank is connected to the spline groove.

[0020] By adopting the above technical solution, an oil storage tank is provided to be connected with the spline groove for storing lubricating oil. When there is no external lubricating oil to be replenished, the lubricating oil in the oil storage tank can temporarily provide lubrication for the spline segment to ensure the service life of the worm body.

[0021] Preferably, the third stage is provided with an annular oil passage, the annular oil passage is connected to the oil storage tank, and the outer side wall of the annular oil passage is inclined toward the direction away from the axis of the third stage at one end close to the spline section.

[0022] By adopting the above technical solution, an annular oil channel is set to facilitate the uniform distribution of lubricating oil in each oil storage tank, and the oil is transported from the oil storage tank to each spline groove to achieve lubrication of the spline segment. The outer side wall of the annular oil channel is close to the end of the spline segment and is inclined away from the axis of the third stage. This helps the lubricating oil in the annular oil channel to move along the outer wall of the annular oil channel toward the oil storage tank when the worm body rotates.

[0023] In summary, the present application includes at least one of the following beneficial technical effects:

[0024] 1. The meshing section is mainly used to mesh with the worm wheel. The diameter of the meshing section is larger than the diameter of the connecting section and the supporting section, which helps to improve the structural strength of the meshing section and the service life of the meshing section, thereby increasing the service life of the worm body;

[0025] 2. The connection between the spline segment and the third stage is transitioned through an inclined surface, which helps to improve the stress distribution between the third stage and the spline segment, reduce the stress concentration phenomenon at the connection between the spline segment and the third stage, reduce the possibility of fracture at the connection between the spline segment and the third stage, and increase the service life of the worm body;

[0026] 3. An oil storage tank is connected to the spline groove to store lubricating oil. When there is no external lubricating oil to replenish, the lubricating oil in the oil storage tank can temporarily provide lubrication for the spline section to ensure the service life of the worm body. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the structure of a worm gear used in a linear steering system of an automobile.

[0028] Figure 2 It is a partial cross-sectional view of a worm gear used in a linear steering system of an automobile.

[0029] Figure 3 It is a partial cross-sectional view of a worm gear used in a linear steering system of an automobile.

[0030] Figure 4 It is a partial cross-sectional view of another embodiment of a worm gear used in a linear steering system of an automobile.

[0031] Description of reference numerals:

[0032] 1. Worm body; 11. Connecting section; 12. Meshing section; 13. Support section; 131. First stress relief chamfer; 14. Chamfer one; 15. Fillet one; 16. First stage; 161. Third stress relief chamfer; 162. Chamfer four; 163. Fillet four; 17. Second stage; 171. Fourth stress relief chamfer; 172. Chamfer five; 173. Fillet five; 18. Third stage; 181. Oil storage tank; 182. Annular oil channel; 183. Fillet six; 19. Spline section; 191. Spline groove; 192. Second stress relief chamfer; 193. Ring groove; 194. Fillet seven; 110. Limiting ring; 1101. Chamfer two; 1102. Fillet two; 111. Embossed groove 1111. Fillet three; 1112. Chamfer three. DETAILED DESCRIPTION

[0033] The present application is further described in detail below in conjunction with the accompanying drawings.

[0034] Reference Figure 1 The embodiment of the present application discloses a worm gear used in a linear steering system of an automobile, including a worm gear body 1. The worm gear body 1 includes a meshing section 12 and a support section 13. The support section 13 is coaxially fixedly connected to one end of the meshing section 12 along the axial direction of the meshing section 12, the diameter of the support section 13 is smaller than the diameter of the meshing section 12, and the outer periphery of the support section 13 away from the end of the meshing section 12 is provided with a first stress relief chamfer 131. A chamfer 14 is provided at the connection between the support section 13 and the meshing section 12, and a fillet 15 is provided at the connection between the chamfer 14 and the support section 13.

[0035] The outer periphery of the support section 13 is coaxially fixedly connected to the limit ring 110, and the connection between the limit ring 110 and the support section 13 is provided with a second chamfer 1101, which is located on the side of the limit ring 110 close to the meshing section 12, and a second rounded corner 1102 is provided at the connection between the second chamfer and the support section 13. An embedded groove 111 is provided on the outer periphery of the support section 13, and the embedded groove 111 is located on the side of the limit ring 110 away from the meshing section 12, and the groove wall of the embedded groove 111 close to the meshing section 12 is flush with the groove wall of the limit ring 110 close to the meshing section 12, and a third rounded corner 1111 is provided on the groove wall of the embedded groove 111 close to the meshing section 12, and a third chamfer 1112 is provided on the groove wall on the other side of the embedded groove 111.

[0036] The worm body 1 also includes a connecting section 11, which is coaxially fixedly connected to an end of the meshing section 12 away from the supporting section 13, and the diameter of the connecting section 11 is smaller than the diameter of the meshing section 12. A chamfer 14 is provided at the connection between the connecting section 11 and the meshing section 12, and a rounded corner 15 is provided at the connection between the chamfer 14 and the connecting section 11.

[0037] The worm body 1 also includes a first stage 16, a second stage 17 and a third stage 18. The first stage 16, the second stage 17 and the third stage 18 are coaxially fixedly connected to the end of the connecting section 11 away from the meshing section 12 in sequence. The diameters of the first stage 16, the second stage 17 and the third stage 18 decrease in sequence along the axis of the connecting section 11 in the direction away from the meshing section 12. The outer periphery of the end of the first stage 16 away from the meshing section 12 is provided with a third stress relief chamfer 161, and the outer periphery of the end of the second stage 17 away from the meshing section 12 is provided with a fourth stress relief chamfer 171. The connection between the first stage 16 and the connecting section 11 is provided with a chamfer 164, and the connection between the chamfer 162 and the connecting section 11 is provided with a fillet 164. The end of the second stage 17 close to the first stage 16 is provided with a chamfer 5 172, and the end of the chamfer 5 172 close to the stage is inclined in the direction close to the axis of the second stage 17, and the connection between the chamfer 5 172 and the first stage 16 is provided with a fillet 5 173. The connection between the second stage 17 and the third stage 18 is provided with a fillet 6 183.

[0038] Reference Figure 1 and Figure 2 The worm body 1 also includes a spline segment 19, which is coaxially fixedly connected to the end of the third stage 18 away from the second stage 17. The outer periphery of the end of the spline segment 19 away from the connecting segment 11 is provided with a second stress relief chamfer 192. The diameter of the spline segment 19 is larger than the diameter of the third stage 18, and the end of the spline segment 19 close to the third stage 18 is transitioned through an inclined surface.

[0039] Reference Figure 1 and Figure 3 The outer periphery of the spline segment 19 is provided with a plurality of spline grooves 191, the spline grooves 191 extend along the axis of the spline segment 19, and the plurality of spline grooves 191 are evenly distributed around the axis of the spline segment 19, and the distance from the bottom of the spline groove 191 to the axis of the spline segment 19 is less than the diameter of the third stage 18. In this embodiment, the cross section of the spline on the outer periphery of the spline segment 19 is an isosceles trapezoid.

[0040] Reference Figure 4 In another embodiment, the cross section of the outer peripheral spline of the spline segment 19 is an equilateral triangle.

[0041] Reference Figure 1 and Figure 2 The outer circumference of the spline segment 19 is coaxially provided with a plurality of annular grooves 193, which are spaced apart along the axis direction of the spline segment 19. The bottom of the annular groove 193 is flush with the bottom of the spline groove 191, and the two sides of the annular groove 193 along the axis direction of the spline segment 19 are respectively provided with fillets 194. In this embodiment, two annular grooves 193 are provided.

[0042] An oil storage tank 181 is provided at one end of the third stage 18 near the spline section 19. The oil storage tank 181 is connected to the spline groove 191. The number of the oil storage tanks 181 is the same as the number of the spline grooves 191 and they correspond one to one. The third stage 18 is provided with an annular oil passage 182. The axis of the annular oil passage 182 coincides with the axis of the third stage 18. The annular oil passage 182 is located on the side of the oil storage tank 181 away from the spline section 19. The annular oil passage 182 is connected to the oil storage tank 181. The outer side wall of the annular oil passage 182 is inclined at one end near the spline section 19 in a direction away from the axis of the third stage 18.

[0043] The implementation principle of a worm gear used in an automobile linear steering system according to an embodiment of the present application is as follows: a bearing is sleeved on the support section 13, the bearing abuts against the side surface of the limit ring 110 away from the meshing section 12, another bearing is sleeved on the outer periphery of the second stage 17, the bearing abuts against one end of the first stage 16 close to the second stage 17, the spline is used for coupling connection, the coupling abuts against one end of the second stage 17 away from the first stage 16, the annular oil passage 182 is used to store lubricating oil, when the worm body 1 rotates, the lubricating oil in the annular oil passage 182 moves in a direction away from the axis of the worm body 1 under the action of centrifugal force, slides along the outer wall of the annular oil passage 182 toward the oil storage tank 181, and then enters the spline groove 191 to lubricate the spline section 19.

[0044] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A worm gear used in a linear steering system of an automobile, characterized in that: The worm body (1) comprises a connecting section (11), a meshing section (12) and a supporting section (13); the connecting section (11) and the supporting section (13) are coaxially connected to two ends of the meshing section (12) respectively; the diameter of the meshing section (12) is larger than the diameters of the supporting section (13) and the connecting section (11).

2. The worm gear used in the automotive linear steering system according to claim 1, characterized in that: Chamfers (14) are provided at the connection points between the two ends of the meshing section (12) and the connecting section (11) and the supporting section (13).

3. The worm gear used in the automotive linear steering system according to claim 2, characterized in that: A rounded corner (15) is provided at the connection between the chamfer (14) and the connecting section (11) or the supporting section (13).

4. The worm gear used in the automotive linear steering system according to claim 1, characterized in that: One end of the connecting section (11) away from the meshing section (12) is coaxially connected in sequence to a first stage (16), a second stage (17), a third stage (18) and a spline section (19); a plurality of spline grooves (191) are provided on the outer periphery of the spline section (19); and the plurality of spline grooves (191) are evenly distributed in the circumferential direction around the axis of the spline section (19).

5. The worm gear used in the automotive linear steering system according to claim 4, characterized in that: The diameters of the first stage (16), the second stage (17) and the third stage (18) decrease in sequence along the axis of the connecting section (11) in a direction away from the meshing section (12).

6. The worm gear used in the automotive linear steering system according to claim 5, characterized in that: The connection between the spline segment (19) and the third stage (18) is transitioned through an inclined surface.

7. The worm gear used in the automotive linear steering system according to claim 6, characterized in that: The distance from the bottom of the spline groove (191) to the axis of the spline segment (19) is smaller than the diameter of the third stage (18); an oil storage groove (181) is provided at one end of the third stage (18) close to the spline segment (19); and the oil storage groove (181) is in communication with the spline groove (191).

8. The worm gear used in the automotive linear steering system according to claim 7, characterized in that: The third stage (18) is provided with an annular oil passage (182); the annular oil passage (182) is connected to the oil storage tank (181); and an end of the outer side wall of the annular oil passage (182) close to the spline section (19) is inclined in a direction away from the axis of the third stage (18).

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