Damper and electric tail door supporting rod

Abstract

The damper comprises a shell, a fixing sleeve, a rotating shaft, an end cover and an elastic piece, the shell is provided with a containing cavity extending along the axis, and one end of the shell is provided with a first through hole communicated with the containing cavity; the fixing sleeve is fixedly arranged in the containing cavity and comprises a rotating cavity and a first annular groove annularly formed in the outer side of the rotating cavity, and a first wear-resistant conical surface is formed on the inner wall of the rotating cavity; the rotating shaft is rotationally arranged in the rotating cavity, a second wear-resistant conical surface is formed on the outer wall of the rotating shaft, the first wear-resistant conical surface is in friction connection with the second wear-resistant conical surface, and the rotating shaft is provided with a shaft hole coaxial with the first through hole; the end cover is movably arranged at the opening of the containing cavity and can move in the axis direction to be close to or away from the fixing sleeve. The elastic piece is arranged in the first annular groove, and the end, close to the end cover, of the elastic piece abuts against the end cover. The damper is simple in structure, the assembling difficulty can be reduced, and the production efficiency can be improved.

Description

Technical Field

[0001] This utility model relates to the field of automotive parts technology, and in particular to a damper and an electric tailgate strut. Background Technology

[0002] As a modern automotive intelligent feature, the power tailgate strut is widely used due to its convenience and practicality. To improve the support performance of the power tailgate strut and achieve hovering at any opening or closing angle, most power tailgate struts incorporate a damper. In existing technology, the damper housing contains multiple layers of friction pads, and frictional damping is achieved through spring preload. This structure is complex, with numerous components, resulting in high cost, and assembly is also complex, impacting production efficiency. Utility Model Content

[0003] To address the aforementioned problems, the purpose of this utility model is to design a damper and an electric tailgate strut, which has a simple structure, reduces assembly difficulty, and improves production efficiency.

[0004] The objective of this utility model is achieved through the following technical solution:

[0005] Design a damper, including:

[0006] The housing has a receiving cavity extending along an axis, and one end of the housing is provided with a first through hole communicating with the receiving cavity;

[0007] A fixing sleeve is fixedly disposed in the accommodating cavity. The fixing sleeve includes a rotating cavity and a first annular groove arranged around the outer side of the rotating cavity. The inner wall of the rotating cavity forms a first wear-resistant conical surface.

[0008] A rotating shaft is rotatably disposed within the rotating cavity. The outer wall of the rotating shaft forms a second wear-resistant conical surface. The first wear-resistant conical surface and the second wear-resistant conical surface are in frictional connection. The rotating shaft is provided with a shaft hole coaxial with the first through hole.

[0009] An end cap is movably disposed at the opening of the accommodating cavity and can move along the axial direction to approach or move away from the fixed sleeve.

[0010] An elastic element is disposed within the first annular groove, and one end of the elastic element near the end cap abuts against the end cap.

[0011] The damper designed in this scheme moves the end cap along the axial direction within the accommodating cavity to move away from or closer to the fixed sleeve, adjusting the preload of the elastic element pressed against the fixed sleeve, thereby changing the friction between the rotating shaft and the fixed sleeve, achieving stepless switching of the damping force from "soft damping" to "hard damping". The conical fit design of the first wear-resistant conical surface of the fixed sleeve and the second wear-resistant conical surface of the rotating shaft increases the friction contact area, avoids local stress concentration, and reduces the wear rate. The conical structure has self-correcting characteristics during rotation, compensating for axial misalignment caused by assembly errors or thermal deformation, ensuring uniform distribution of damping force. By setting a first annular groove in the fixed sleeve to limit and fix the elastic element, it is easier to install the elastic element into the fixed sleeve during assembly. Then, the end cap encapsulates the fixed sleeve, rotating shaft, and elastic element within the accommodating cavity, reducing assembly difficulty. The outer shell integrates the fixed sleeve, rotating shaft, and elastic element into a single cavity; the axial layout saves installation space and is suitable for embedded installation. When the damper of this solution is installed in the outer sleeve of the electric tailgate strut, the lead screw of the electric tailgate strut is fixedly connected to the shaft hole and passes through the end cover. The lead screw is connected to the output end of the drive motor. The drive motor drives the lead screw to rotate, which in turn drives the shaft to rotate. The fixed sleeve remains stationary relative to the outer shell. The relative rotation between the shaft and the fixed sleeve generates friction, which in turn generates a damping torque on the lead screw, increasing the effective internal resistance of the electric tailgate strut and giving the car tailgate a good hovering effect.

[0012] Furthermore, the first annular groove includes an inclined wall extending obliquely from the bottom to the top.

[0013] By setting an inclined wall, the opening width at the top of the first annular groove is made wider than the width at the bottom of the groove, making it easier to assemble the elastic element into the first annular groove.

[0014] Furthermore, the end cap includes an end plate and a connecting plate circumferentially disposed around the end plate, with one end of the elastic member abutting against the end plate.

[0015] The end cap is an integral structure, and the end plate is the direct bearing surface of the elastic element. The end plate adopts a planar contact design with the elastic element to ensure uniform distribution of preload.

[0016] Furthermore, the outer wall of the connecting plate is provided with an external thread, and the inner wall of the accommodating cavity is provided with an internal thread that matches the external thread.

[0017] The threaded fit between the outer wall of the connecting plate and the inner wall of the accommodating cavity, through a dual mechanism of mechanical locking and stepless adjustment, improves the damper's assembly accuracy, dynamic stability, and maintainability. Fine-tuning of the end cap's axial displacement is achieved by rotating the end cap, precisely controlling the compression of the elastic element. The self-locking characteristic of the threaded pair ensures that the preload does not loosen under vibration.

[0018] Furthermore, the end plate has a second through hole, which is coaxial with the shaft hole.

[0019] The second through hole is located in the middle of the end plate and is coaxial with the shaft hole. After the lead screw passes through the shaft hole of the rotating shaft, it passes through the second through hole again and connects to the output end of the drive motor.

[0020] Furthermore, the end plate is provided with an inner baffle on the side near the elastic member. The inner baffle is arranged around the second through hole, and the inner baffle and the connecting plate enclose each other to form a second annular groove for accommodating the end of the elastic member.

[0021] The end cap has a second through hole around the inner baffle and forms a second annular groove with the connecting plate to achieve precise positioning of the end of the elastic element. The first annular groove and the second annular groove cooperate to form a limiting cavity for the elastic element, which constrains the assembly position of the elastic element, suppresses radial displacement under high-frequency vibration, and ensures that the preload is uniformly transmitted along the axis.

[0022] Furthermore, the outer periphery of the fixing sleeve is provided with a plurality of first limiting protrusions, and the inner wall of the accommodating cavity is provided with limiting grooves corresponding one-to-one with the limiting protrusions.

[0023] Multiple sets of first limiting protrusions are provided on the outer periphery of the fixed sleeve, forming a mechanical interlocking structure with the corresponding limiting grooves on the inner wall of the accommodating cavity. Through geometric constraint reinforcement, the micro-displacement of the fixed sleeve under vibration, impact, or thermal expansion is suppressed, ensuring uniform contact pressure between the first and second wear-resistant conical surfaces. The first limiting protrusions adopt a guide chamfer design, which, together with the flared structure of the limiting groove inlet, enables blind insertion assembly of the fixed sleeve, shortening the assembly time and eliminating the need for precision adjustment tooling.

[0024] Furthermore, the inner wall of the cavity extends a plurality of second limiting protrusions along the axial direction from the bottom near the first through hole, and the limiting groove is formed between two adjacent second limiting protrusions.

[0025] By setting a second limiting protrusion on the inner wall of the accommodating cavity, the structure is strengthened, which can improve the strength of the outer shell compared to setting a limiting groove on the inner wall of the accommodating cavity.

[0026] Furthermore, the inner wall of the shaft hole is provided with an internal spline.

[0027] The end of the lead screw is a splined shaft. The splined part of the splined shaft weds into the inner spline of the shaft hole, thereby achieving a stable connection between the lead screw and the rotating shaft, ensuring the stability of the damping torque output and reducing the deviation of the forward and reverse torque.

[0028] This utility model also designs an electric tailgate support rod, including the aforementioned damper.

[0029] The electric tailgate strut also includes a lead screw and an outer sleeve. The outer sleeve is fixed inside the outer sleeve. The lead screw passes through the first through hole and connects to the shaft hole, and passes through the second through hole. The end of the lead screw passing through the second through hole is connected to the output end of the drive motor through a transmission structure.

[0030] Compared with the prior art, the beneficial effects of this utility model are:

[0031] The damper designed in this scheme moves the end cap along the axial direction within the accommodating cavity to move away from or closer to the fixed sleeve, adjusting the preload of the elastic element pressed against the fixed sleeve, thereby changing the friction between the rotating shaft and the fixed sleeve, achieving stepless switching of the damping force from "soft damping" to "hard damping". The conical fit design of the first wear-resistant conical surface of the fixed sleeve and the second wear-resistant conical surface of the rotating shaft increases the friction contact area, avoids local stress concentration, and reduces the wear rate. The conical structure has self-correcting characteristics during rotation, compensating for axial misalignment caused by assembly errors or thermal deformation, ensuring uniform distribution of damping force. By setting a first annular groove in the fixed sleeve to limit and fix the elastic element, it is easier to install the elastic element into the fixed sleeve during assembly. Then, the end cap encapsulates the fixed sleeve, rotating shaft, and elastic element within the accommodating cavity, reducing assembly difficulty. The outer shell integrates the fixed sleeve, rotating shaft, and elastic element into a single cavity; the axial layout saves installation space and is suitable for embedded installation. When the damper of this solution is installed in the outer sleeve of the electric tailgate strut, the lead screw of the electric tailgate strut is fixedly connected to the shaft hole and passes through the end cover. The lead screw is connected to the output end of the drive motor. The drive motor drives the lead screw to rotate, which in turn drives the shaft to rotate. The fixed sleeve remains stationary relative to the outer shell. The relative rotation between the shaft and the fixed sleeve generates friction, which in turn generates a damping torque on the lead screw, increasing the effective internal resistance of the electric tailgate strut and giving the car tailgate a good hovering effect. Attached Figure Description

[0032] Figure 1 This is an exploded view of the structure of a damper according to an embodiment of the present invention.

[0033] Figure 2 This is a cross-sectional view of a damper according to an embodiment of the present invention.

[0034] Figure 3 This is a top view of the outer casing of an embodiment of the present invention.

[0035] Figure 4 This is a schematic diagram of the structure of the fixing sleeve according to an embodiment of the present invention.

[0036] Figure 5 This is a schematic diagram of the end cap structure according to an embodiment of the present invention.

[0037] Illustration: 1. Outer shell; 11. Receiving cavity; 111. Internal thread; 112. Second limiting protrusion; 113. Limiting groove; 12. First through hole; 2. Fixing sleeve; 21. Rotating cavity; 22. First annular groove; 221. Inclined wall; 23. First wear-resistant conical surface; 24. First limiting protrusion; 3. Rotating shaft; 31. Second wear-resistant conical surface; 32. Shaft hole; 321. Internal spline; 4. End cap; 41. End plate; 411. Second through hole; 412. Inner baffle; 42. Connecting plate; 421. External thread; 43. Second annular groove; 5. Elastic element. Detailed Implementation

[0038] To facilitate understanding of this invention, a more comprehensive description will be provided below with reference to the accompanying drawings. The drawings illustrate preferred embodiments of the invention. However, this invention can be implemented in many different forms and is not limited to the embodiments described herein.

[0039] like Figures 1 to 5 As shown, this embodiment provides a damper, including a housing 1, a fixing sleeve 2, a rotating shaft 3, an elastic element 5, and an end cap 4. The housing 1 has a cylindrical structure and a receiving cavity 11 extending along the axis. One end of the housing 1 is provided with a first through hole 12 communicating with the receiving cavity 11. The fixing sleeve 2 is fixedly disposed in the receiving cavity 11. The fixing sleeve 2 includes a rotating cavity 21 and a first annular groove 22 surrounding the outside of the rotating cavity 21. The inner wall of the rotating cavity 21 forms a first wear-resistant conical surface 23. The rotating shaft 3 is rotatably disposed in the rotating cavity 21. Inside, the outer wall of the rotating shaft 3 forms a second wear-resistant conical surface 31, and the first wear-resistant conical surface 23 is frictionally connected to the second wear-resistant conical surface 31. The rotating shaft 3 is provided with a shaft hole 32 coaxial with the first through hole 12. The diameter of the first through hole 12 is larger than the diameter of the shaft hole 32. The inner wall of the shaft hole 32 is provided with an internal spline 321. The end cap 4 is movably disposed at the opening of the accommodating cavity 11 and can move along the axial direction to approach or move away from the fixed sleeve 2. The elastic element 5 is disposed in the first annular groove 22, and the end near the end cap 4 abuts against the end cap 4. The first annular groove 22 includes an inclined wall 221 extending inclinedly from the bottom to the top. By setting the inclined wall 221, the width of the top opening of the first annular groove 22 is greater than the width of the bottom of the groove, making it easier to assemble the elastic element 5 into the first annular groove 22.

[0040] Specifically, the elastic element 5 can be a compression spring, wave spring, or other stretchable elastic structure. The rotating shaft 3 and the fixing sleeve 2 can be made of carbon fiber material after heat treatment, which has a high carbon content, is lightweight, and has high strength. The first wear-resistant conical surface 23 and the second wear-resistant conical surface 31 can be coated with a wear-resistant resin layer to enhance wear resistance.

[0041] like Figure 2 and Figure 5As shown, the end cap 4 includes an end plate 41 and a connecting plate 42 surrounding the end plate 41. The end plate 41 has a second through hole 411, which is coaxial with the shaft hole 32. The end cap 4 has an inner baffle 412 on the side near the elastic member 5, which surrounds the second through hole 411. The inner baffle 412 and the connecting plate 42 enclose each other to form a second annular groove 43 for accommodating the end of the elastic member 5. One end of the elastic member 5 abuts against the end plate 41. The end cap 4, through the inner baffle 412 surrounding the second through hole 411 and the second annular groove 43 formed by the connection plate 42, achieves precise positioning of the end of the elastic member 5. The first annular groove 22 and the second annular groove 43 cooperate to form a limiting cavity for the elastic member 5, constraining the assembly position of the elastic member 5, suppressing radial displacement under high-frequency vibration, and ensuring that the preload is uniformly transmitted along the axis. The end cap 4 is an integral structure, and the end plate 41 is the direct bearing surface of the elastic element 5. A planar contact design is used between the end cap 41 and the elastic element 5 to ensure uniform distribution of preload. The outer wall of the connecting plate 42 has an external thread 421, and the inner wall of the accommodating cavity 11 has an internal thread 111 that matches the external thread 421. The threaded fit design between the outer wall of the connecting plate 42 and the inner wall of the accommodating cavity 11, through a dual mechanism of mechanical locking and stepless adjustment, improves the damper's assembly accuracy, dynamic stability, and maintainability. Rotating the end cap 4 allows for fine-tuning of its axial displacement, precisely controlling the compression of the elastic element 5. The self-locking characteristic of the threaded pair ensures that the preload does not loosen under vibration.

[0042] like Figure 4 As shown, the outer periphery of the fixing sleeve 2 is provided with multiple first limiting protrusions 24, and the inner wall of the accommodating cavity 11 extends multiple second limiting protrusions 112 along the axial direction from the bottom near the first through hole 12. A limiting groove 113 is formed between two adjacent second limiting protrusions 112. The multiple sets of first limiting protrusions 24 on the outer periphery of the fixing sleeve 2 form a mechanical interlocking structure with the corresponding limiting grooves 113 on the inner wall of the accommodating cavity 11. Through geometric constraint reinforcement, the micro-displacement of the fixing sleeve 2 under vibration, impact or thermal expansion is suppressed, ensuring uniform contact pressure between the first wear-resistant conical surface 23 and the second wear-resistant conical surface 31. The first limiting protrusions 24 adopt a guide chamfer design, which, together with the flared structure of the entrance of the limiting groove 113, enables blind insertion assembly of the fixing sleeve 2, shortening the assembly time and eliminating the need for precision adjustment tooling. By providing second limiting protrusions 112 on the inner wall of the accommodating cavity 11, the structure is strengthened. Compared with the method of digging limiting grooves on the inner wall of the accommodating cavity 11, the strength of the outer shell 1 can be improved.

[0043] This utility model also provides an electric tailgate strut, including the aforementioned damper, lead screw, and outer sleeve. The outer sleeve 1 is fixed inside the outer sleeve. The lead screw passes through the first through hole 12 and connects to the shaft hole 32, and passes through the second through hole 411. The end of the lead screw passing through the second through hole 411 is connected to the output end of the drive motor through a transmission structure. The end of the lead screw is a splined shaft, and the splined part of the splined shaft weds into the inner spline 321 of the shaft hole 32, thereby achieving a stable connection between the lead screw and the rotating shaft, ensuring the stability of the damping torque output, and reducing the deviation of the forward and reverse torque.

[0044] The damper provided by this utility model moves along the axial direction within the accommodating cavity 11 via the end cap 4 to move away from or closer to the fixed sleeve 2, adjusting the preload of the elastic element 5 pressed against the fixed sleeve 2, thereby changing the frictional force between the rotating shaft 3 and the fixed sleeve 2, achieving stepless switching of the damping force from "soft damping" to "hard damping". The conical fit design of the first wear-resistant conical surface 23 of the fixed sleeve 2 and the second wear-resistant conical surface 31 of the rotating shaft 3 increases the frictional contact area, avoids local stress concentration, and reduces the wear rate. The conical structure has self-correcting characteristics during rotation, compensating for axial misalignment caused by assembly errors or thermal deformation, ensuring uniform distribution of damping force. By providing a first annular groove 22 to limit and fix the elastic element 5 within the fixed sleeve 2, it is easier to install the elastic element 5 into the fixed sleeve 2 during assembly. Then, the end cap 4 encapsulates the fixed sleeve 2, rotating shaft 3, and elastic element 5 within the accommodating cavity 11, reducing assembly difficulty. The outer casing 1 integrates the fixing sleeve 2, the rotating shaft 3, and the elastic element 5 into a single cavity. The axial layout saves installation space and is suitable for embedded installation. When the damper of this solution is installed in the outer sleeve of the electric tailgate strut, the lead screw of the electric tailgate strut is fixedly connected to the shaft hole 32 and passes through the end cover 4. The lead screw is connected to the output end of the drive motor. The drive motor drives the lead screw to rotate, which in turn drives the rotating shaft 3 to rotate. The fixing sleeve 2 remains stationary relative to the outer casing 1. The relative rotation between the rotating shaft 3 and the fixing sleeve 2 generates friction, which in turn generates a damping torque on the lead screw, increasing the effective internal resistance of the electric tailgate strut and giving the car tailgate a good hovering effect.

[0045] In the description of this utility model, it should be understood that terms such as "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model 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 utility model.

[0046] Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, the inclusion of "first," "second," etc., in a feature may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0047] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A damper characterized by, include: The housing has a receiving cavity extending along an axis, and one end of the housing is provided with a first through hole communicating with the receiving cavity; A fixing sleeve is fixedly disposed in the accommodating cavity. The fixing sleeve includes a rotating cavity and a first annular groove arranged around the outside of the rotating cavity. The inner wall of the rotating cavity forms a first wear-resistant conical surface. A rotating shaft is rotatably disposed within the rotating cavity. The outer wall of the rotating shaft forms a second wear-resistant conical surface. The first wear-resistant conical surface and the second wear-resistant conical surface are in frictional connection. The rotating shaft is provided with a shaft hole coaxial with the first through hole. An end cap is movably disposed at the opening of the accommodating cavity and can move along the axial direction to approach or move away from the fixed sleeve. An elastic element is disposed within the first annular groove, and one end of the elastic element near the end cap abuts against the end cap.

2. The damper of claim 1, wherein The first annular groove includes an inclined wall that extends at an angle from bottom to top.

3. The damper of claim 1, wherein The end cap includes an end plate and a connecting plate circumferentially disposed on the end plate, and one end of the elastic member abuts against the end plate.

4. The damper of claim 3, wherein The outer wall of the connecting plate is provided with external threads, and the inner wall of the accommodating cavity is provided with internal threads that match the external threads.

5. The damper of claim 3, wherein The end plate has a second through hole, which is coaxial with the shaft hole.

6. The damper according to claim 5, characterized in that, The end plate is provided with an inner baffle on the side near the elastic member. The inner baffle is arranged around the second through hole, and the inner baffle and the connecting plate form a second annular groove to accommodate the end of the elastic member.

7. The damper of claim 1, wherein The outer periphery of the fixed sleeve is provided with a plurality of first limiting protrusions, and the inner wall of the accommodating cavity is provided with limiting grooves corresponding one-to-one with the limiting protrusions.

8. The damper of claim 7, wherein, The inner wall of the cavity extends a plurality of second limiting protrusions along the axial direction from the bottom near the first through hole, and the limiting groove is formed between two adjacent second limiting protrusions.

9. The damper of claim 1, wherein, The inner wall of the shaft hole is provided with an internal spline.

10. An electric tailgate stay bar, characterized by, Includes the damper as described in any one of claims 1-9.

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