Servo motor elastic heat-conducting bushing, assembling assembly and assembling method

Abstract

This invention discloses a servo motor elastic thermally conductive bushing, an assembly assembly, and an assembly method. The bushing body is made of a high thermal conductivity elastic material, with a circumferential groove, an integrated axial sealing structure, and an integrally formed axial anti-detachment structure at the end. The bushing is interference-fitted between the servo motor and the narrow, thin-walled mounting hole. The circumferential groove absorbs the interference and accommodates thermal expansion, preventing deformation of the mounting base. The integrated sealing and anti-detachment structure eliminates the need for additional accessories, saving assembly space. The assembly assembly is specifically designed for robot joint thin-walled cavities, high power density, and high-frequency vibration conditions. It is easy to assemble and combines multiple functions such as efficient heat conduction, vibration buffering, dustproof sealing, and axial anti-detachment. It features a simplified structure, stable performance, and strong practicality, specifically adapting to the demanding operating conditions of next-generation robots, improving equipment operational stability and service life.

Description

Technical Field

[0001] This invention belongs to the field of precision servo motor supporting components, precision assembly, vibration buffering and heat dissipation technology. Specifically, it relates to an elastic heat-conducting bushing structure that is adapted to narrow and thin-walled assembly spaces and has the functions of thermal expansion self-adaptation, integrated sealing and limiting, and efficient heat conduction and vibration reduction. It is especially suitable for the special working conditions of humanoid robots, quadruped robots with thin-walled and narrow joint cavities, high power density, long-term continuous operation, and high-frequency alternating vibration. It can also be extended to similar harsh assembly scenarios such as UAV servo motors and small precision servo transmission mechanisms. Background Technology

[0002] Thin-walled, narrow assembly structures for humanoid and quadrupedal robots have been widely used for many years. Early models had low power density, low heat generation, and mostly operated intermittently. Conventional structures such as segmented thermal conductive silicone pads, open elastic sleeves, and direct coating of thermal conductive gel could meet basic heat dissipation, simple protection, and assembly requirements, and were suitable for the relatively relaxed operating conditions in the early days.

[0003] With the technological iteration of the robotics industry, joint mechanisms are continuously evolving towards extreme lightweighting, thinner shells, and higher power density motors. Simultaneously, higher demands are placed on the stability, reliability, and service life of equipment under long-term continuous operation and high-frequency start-stop alternating vibration conditions. Under these demanding conditions, conventional thermally conductive and vibration-damping assembly structures are gradually revealing their performance limitations: conventional segmented thermally conductive structures are susceptible to displacement and warping due to vibration, leading to discontinuous heat conduction paths and reduced heat dissipation efficiency; ordinary non-grooved elastic bushings are difficult to adapt to radial interference fits, and the thermal expansion of rubber materials can easily compress the thin-walled mounting base, causing deformation of the mounting base and motor sluggishness; independent sealing and limiting parts require additional assembly space, conflicting with the integrated design requirements of narrow cavities; ordinary elastic sleeves lack integrated anti-detachment structures, making them prone to axial movement and loosening failure under long-term alternating vibration.

[0004] Based on the aforementioned industry development needs and the performance limitations of existing conventional structures, there is an urgent need to propose a special elastic thermally conductive bushing structure that is structurally simplified, adaptable to narrow and thin-walled spaces, and capable of interference fit assembly, thermal expansion self-adaptation, efficient heat conduction, high-frequency vibration reduction, and integrated sealing to prevent detachment, in order to meet the stringent operating requirements of next-generation robot joints. Summary of the Invention

[0005] The purpose of this invention is to address the limitations of existing conventional assembly structures in adapting to the harsh conditions of robot joints with narrow walls, high power density, and high-frequency vibration. This invention provides a servo motor elastic heat-conducting bushing, assembly assembly, and assembly method that are structurally reasonable, easy to assemble, and have stable performance. It achieves integrated assembly without additional auxiliary parts and takes into account multiple functions such as heat conduction, shock absorption, sealing, anti-detachment, and thermal expansion self-adaptation.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] I. Elastic thermally conductive bushing structure

[0008] A servo motor elastic thermal conductive bushing includes a bushing body, which is made of a highly thermally conductive, insulating, flame-retardant, and oil-resistant elastic silicone rubber material (e.g., Shore hardness 50±5A), possessing excellent elastic deformation capability, thermal conductivity and heat dissipation performance, and environmental adaptability.

[0009] The outer or inner circumferential surface of the bushing body is provided with circumferential grooves. The circumferential grooves are spaced apart or continuously arranged along the bushing axis. The groove cross-section adopts a circular arc, rectangular, trapezoidal or V-shaped structure. The groove depth is 30% to 70% of the bushing body wall thickness, which ensures the overall strength of the structure and provides sufficient deformation space.

[0010] The bushing body is integrated with an axial sealing structure in the axial region of the circumferential groove. The axial sealing structure adopts one of the following two forms:

[0011] 1. The circumferential groove is not completely through the bushing axial direction. The solid section of the groove that is not through is within the assembly mating area. After the assembly is compressed, the solid section forms an axial seal to achieve dust and oil medium barrier.

[0012] 2. The circumferential groove is fully continuous along the axial direction of the bushing. One or more annular sealing ribs are integrally formed at the axial end of the bushing or in the outer circumferential mating section. During assembly, the sealing ribs are deformed under pressure to form an axial seal.

[0013] The bushing body has non-grooved, non-elastic deformation zones at both axial ends. The non-elastic deformation zones at the ends are integrally formed with an axial anti-detachment structure. The axial anti-detachment structure is an annular flange, an annular stop, or a snap-locking limit structure. Its outer diameter in the free state is larger than the diameter of the assembly and installation hole.

[0014] As a preferred embodiment, an annular transition groove can be integrally formed between the inelastic deformation zone and the elastic compensation zone with the circumferential groove. The annular transition groove provides clearance space for the radial shrinkage deformation of the axial anti-detachment structure, avoids assembly interference during the press-fitting process, and ensures smooth assembly.

[0015] The bushing body adopts an integrated vulcanized molding structure. The elastic compensation area and the end non-elastic deformation area can be integrally molded using elastic materials of the same hardness. For heavy-duty working conditions, a heterogeneous composite structure can also be adopted, that is, the end non-elastic deformation area uses an elastic material with a hardness slightly higher than that of the elastic compensation area, and is composited into one piece through a co-vulcanization process, taking into account both elastic deformation and rigid limiting requirements.

[0016] Furthermore, the circumferential groove can be filled with a solid or paste-like heat-conducting medium. After assembly, the heat-conducting medium is sealed in the groove cavity, which further improves the radial heat conduction efficiency of the bushing and enhances the heat dissipation effect of the motor.

[0017] II. Assembly Structure

[0018] A servo motor elastic thermal conductive bushing assembly includes a servo motor, a mounting base, and the aforementioned elastic thermal conductive bushing. The mounting base specifically refers to a narrow, thin-walled mounting structure such as a robot joint thin-walled shell or a drone servo motor shell.

[0019] The elastic thermally conductive bushing is fitted between the outer periphery of the servo motor and the mounting hole of the mounting base with an interference fit. After assembly, the circumferential groove is in an elastic compression deformation state, absorbing the radial interference while reserving space for thermal expansion. The axial sealing structure fits tightly against the mating surface to form a stable seal. After the end axial anti-detachment structure is assembled, it elastically rebounds and abuts against the end face of the mounting base or the motor shaft shoulder to achieve axial limiting and anti-detachment.

[0020] The overall assembly does not require additional seals, fasteners, limit rings or other auxiliary parts, forming an integrated assembly structure that integrates gap compensation, efficient heat conduction, vibration buffering, dustproof sealing and axial anti-detachment, and is fully adaptable to the integrated assembly needs of narrow and thin-walled spaces.

[0021] III. Assembly Method

[0022] An assembly method for a servo motor elastic thermal conductive bushing specifically includes the following steps:

[0023] S1. Selection Pre-processing: Based on the outer diameter of the robot joint servo motor and the mounting hole diameter of the mounting base, select the appropriate specification of elastic heat-conducting bushing, clean the inner and outer walls of the bushing, the outer surface of the servo motor, and the inner wall of the mounting hole to remove oil, dust and other impurities, and ensure that the mating surfaces are clean.

[0024] S2. Pre-assembly positioning: The elastic heat-conducting bushing is coaxially fitted onto the outside of the servo motor. Relying on the elastic clamping force of the bushing itself, the coaxial pre-positioning with the motor is achieved. Alternatively, a guide fixture can be used to smoothly press the servo motor into the inner hole of the bushing.

[0025] S3. Overall Press Fitting: The servo motor with the elastic heat-conducting bushing is positioned by the coaxial guide tool and pressed into the mounting hole of the mounting base in an overall coaxial manner; during the pressing process, the circumferential groove adapts to elastic deformation to absorb the radial interference, and the end axial anti-detachment structure is squeezed radially by the mounting hole to pass smoothly through the mounting hole without assembly jamming.

[0026] S4. Positioning and Limiting Fixing: After the servo motor and bushing are pressed into place, the axial anti-detachment structure at the end is released from the compression constraint of the mounting hole, elastically rebounds and resets, forming abutment limit with the end face of the mounting base or the shoulder of the motor shaft, and axial anti-detachment is achieved by relying on the bushing's own structure.

[0027] Beneficial effects

[0028] 1. This invention achieves radial interference absorption and thermal expansion space reservation through circumferential groove structure design, avoiding the compression of thin-walled mounting base by thermal expansion of rubber material, effectively preventing deformation of mounting base and motor operation jamming, and adapting to the stable operation requirements of robot joints in the full temperature range;

[0029] 2. The integrated axial sealing and axial anti-loosening structure eliminates the need for additional seals, limiters, and fasteners, greatly simplifying the assembly structure, saving assembly space in narrow cavities, and achieving integrated assembly with high assembly efficiency and strong stability.

[0030] 3. It adopts a special high thermal conductivity elastic silicone rubber material, and the full-circle full-coverage structure ensures a continuous heat conduction path and uniform heat dissipation. At the same time, it has excellent vibration buffering performance, effectively reducing the impact of alternating vibration of the motor and improving the joint operation stability and service life.

[0031] 4. The structure is simple, the one-piece molding process is mature, the assembly method is simple and easy, no complicated tooling is required, it is suitable for mass production, and it is specifically optimized for the harsh working conditions of robot joints with narrow and thin walls, high power density, and high frequency vibration, making it highly targeted and practical. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the structure of the bushing body of the present invention (showing the circumferential groove 11, the inelastic deformation zone 12, and the annular transition groove 13).

[0033] Figure 2 This is a radial assembly diagram of the assembly assembly of the present invention (showing that the bushing 1 is assembled between the servo motor 2 and the mounting base 3, and the anti-detachment structure 12 abuts against the end face of the mounting base).

[0034] Figure Labels

[0035] 1-Bushing body; 11-Circumferential groove; 12-Non-elastic deformation zone (including anti-detachment structure); 13-Annular transition groove; 2-Servo motor; 3-Mounting base. Detailed Implementation

[0036] The dimensions and structural parameters involved in the following embodiments are merely examples and do not limit the scope of protection of the present invention. Those skilled in the art can make flexible adjustments according to actual working conditions.

[0037] Example 1

[0038] A servo motor elastic thermally conductive bushing, wherein the bushing body 1 is integrally molded from Shore 50±5A high thermal conductivity, flame retardant and oil-resistant silicone rubber (as an example, the hardness can be adjusted according to the working conditions), and an arc-shaped circumferential groove 11 is formed on the outer circumferential surface, the depth of the groove 11 being 50% of the wall thickness of the bushing body 1. The groove 11 is provided with multiple non-through structures in the axial direction (for example, multiple circumferential arc grooves are arranged at intervals along the axial direction), and the solid section of the non-through section is located in the mating area between the bushing 1 and the mounting hole, and is radially compressed during assembly to form a continuous axial sealing surface. The non-elastic deformation areas 12 at both ends of the bushing are integrally molded with annular flange-type anti-detachment structures, and an annular transition groove 13 is preferably provided between the elastic compensation area and the non-elastic deformation area 12.

[0039] In this embodiment, bushing 1 is specifically designed for the thin-walled cavity of the humanoid robot joint. It is interference-fitted between the servo motor 2 and the mounting base 3, ensuring smooth press-fitting. After reaching the correct position, it automatically limits the position, and there are no thermal expansion or overpressure issues throughout the process. It also provides stable thermal conductivity, shock absorption, sealing, and anti-detachment performance.

[0040] Example 2

[0041] A servo motor elastic thermal conductive bushing has a bushing body 1 with a heterogeneous composite structure. The elastic compensation area is made of Shore 50±5A high thermal conductivity silicone rubber, and the end non-elastic deformation area 12 is made of Shore 65±5A elastic rubber. The bushing is co-vulcanized and integrally molded. A rectangular circumferential groove 11 is opened on the outer periphery. The groove 11 is through-type and the end of the bushing is integrally formed with an annular sealing rib. The groove 11 can be filled with a paste-like thermal conductive medium to improve heat dissipation efficiency.

[0042] In this embodiment, bushing 1 is suitable for heavy-duty quadruped robot joints, which combines rigid limiting and elastic deformation, has excellent heat dissipation performance, and does not have problems such as movement, looseness, or sealing failure under long-term high-frequency vibration conditions.

Claims

1. A resilient thermally conductive sleeve for a servo motor, comprising a sleeve body, characterised in that: The bushing body is made of a high thermal conductivity elastic material, and its outer or inner circumferential surface is provided with a circumferential groove. The bushing body is provided with an axial sealing structure in the axial section of the circumferential groove. The bushing body is interference-fitted between the outer circumference of the servo motor and the mounting hole. The circumferential groove can generate elastic deformation when subjected to radial pressure to absorb the compression deformation caused by the radial interference. At the same time, the cavity inside the groove accommodates the thermal expansion volume generated by the working temperature rise of the high thermal conductivity elastic material. The axial end of the bushing body is provided with a non-elastic deformation zone, and the non-elastic deformation zone is integrally formed with an axial anti-detachment structure.

2. The elastomeric thermally conductive bushing for a servo motor of claim 1, wherein: The axial sealing structure is a solid sealing section formed by a non-through circumferential groove, or an annular sealing rib integrally formed by a bushing.

3. The elastomeric thermally conductive bushing for a servo motor of claim 1, wherein: The axial anti-detachment structure is an annular flange, an annular retaining edge, or an inverted limiting structure, with its outer diameter in the free state being larger than the diameter of the mounting hole.

4. The servo motor elastic thermal conductive bushing according to claim 1, characterized in that: An annular transition groove is provided between the inelastic deformation zone and the elastic compensation zone with a circumferential groove, which provides clearance space for the radial shrinkage deformation of the axial anti-detachment structure.

5. The servo motor elastic thermal conductive bushing according to claim 1, characterized in that: The circumferential groove has a cross-section that is arc-shaped, rectangular, trapezoidal, or V-shaped, and the groove depth is 30% to 70% of the bushing body wall thickness.

6. The servo motor elastic thermal conductive bushing according to claim 1, characterized in that: The bushing body is an integrally molded structure. The elastic compensation area and the non-elastic deformation area are integrally vulcanized using materials of the same hardness, or are co-vulcanized and composite molded using heterogeneous elastic materials.

7. The servo motor elastic thermal conductive bushing according to claim 1, characterized in that: The circumferential groove is filled with a solid or paste-like thermally conductive medium.

8. A servo motor elastic thermal conductive bushing assembly, characterized in that: It includes a servo motor, a mounting base, and the elastic thermally conductive bushing as described in any one of claims 1-7; the mounting base is a thin-walled shell of a robot joint or a servo motor shell of a drone, the elastic thermally conductive bushing is interference-fitted between the servo motor and the mounting base, and the axial anti-detachment structure abuts and limits the end face of the mounting base or the shoulder of the motor shaft.

9. A method for assembling the assembly according to claim 8, characterized in that, Includes the following steps: S1. Clean the mating surfaces of the elastic thermal conductive bushing, servo motor, and mounting base to remove impurities and oil stains; S2. Coaxially mount the elastic thermally conductive bushing onto the outside of the servo motor to complete the pre-positioning; S3. Using a guide fixture, press the servo motor with bushings into the mounting hole of the mounting base. S4. After pressing into place, the axial anti-detachment structure elastically rebounds to achieve axial limiting and complete the assembly.

10. A robot or drone, characterized in that: It includes a robot body or a drone body, and the servo motor elastic thermal conductive bushing assembly as described in claim 8; the assembly is disposed at the joint of the robot or inside the servo motor of the drone.

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