Motor reduction mechanism

Abstract

The application provides a motor speed reduction mechanism, which comprises a shell, a sun shaft arranged in the shell, a plurality of planet shafts and two floating tooth block groups. The sun shaft is arranged along the shell axis, the plurality of planet shafts are arranged in a circle around the sun shaft, the middle part of each planet shaft is provided with a first helical tooth part which is in threaded engagement with the inner wall of the shell, and the two ends of each planet shaft are provided with a second helical tooth part which is in engagement with the tooth block group. The tooth block group comprises a plurality of radially floating arc-shaped tooth blocks, each arc-shaped tooth block is inserted into a groove on the shell through a connecting part and is reset by an elastic gasket. The application has the advantages of compact structure and stable transmission, the tooth block group can realize error compensation and impact buffering during engagement, and the service life and operation reliability are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of motor transmission, and in particular to a motor reduction mechanism with floating compensation and buffering functions. Background Art

[0002] Motor reduction mechanisms are widely used in industrial automation equipment, smart curtains, smart door controls, and other fields. Coaxial multi-stage planetary reduction mechanisms are particularly common, offering compact design and high transmission efficiency. In the prior art, a typical planetary reduction mechanism typically consists of a sun shaft driven by a motor, multiple planetary shafts surrounding it, and an internal gear ring fixed to the inside of a housing. The meshing of the planetary shafts with the sun shaft and internal gear ring enables the regulation and transmission of speed and torque.

[0003] However, in traditional designs, the internal gear ring often utilizes a rigid, integrally molded ring structure, which is unable to provide floating compensation based on actual operating conditions. During actual operation, if there are manufacturing and assembly errors in the gears, thermal expansion caused by temperature rise, or meshing shock caused by load fluctuations, the rigid ring gear structure is unable to absorb and buffer these uncertainties. This can easily lead to meshing instability, increased noise, localized wear on the tooth surfaces, and even structural damage, affecting the long-term stable operation of the equipment. Summary of the Invention

[0004] The present invention provides a motor reduction mechanism, which aims to solve the problems in the prior art of the traditional internal gear ring structure, such as high rigidity, inability to perform floating compensation, and susceptibility to unstable meshing and early damage to the tooth surface.

[0005] The motor reduction mechanism provided by the present invention comprises:

[0006] A cylindrical shell, which is axially divided into a middle section located in the middle and two end sections located on both sides of the middle section, the middle section is provided with an axially extending internal thread structure, and the inner circumferential wall of each end section is provided with a plurality of grooves spaced apart along the circumference;

[0007] Two tooth block groups are respectively arranged in the two end sections, each tooth block group includes a plurality of arcuate tooth blocks that can be circumferentially assembled to form an annular inner gear ring structure for meshing, and a connecting portion extending radially outward is provided on the outer arc surface of each arcuate tooth block, the connecting portion is inserted into a groove provided one-to-one with the connecting portion, and an elastic gasket is provided between the connecting portion and the bottom surface of the groove, and a first gap is provided between the outer arc surface of each arcuate tooth block and the inner circumferential wall of the corresponding end section to allow the arcuate tooth block to float in the radial direction, and the elastic gasket is used to provide a radially inward elastic reset force to the arcuate tooth block;

[0008] a sun shaft, which axially passes through the housing and can be driven to rotate by the motor;

[0009] A plurality of planetary shafts are arranged circumferentially around the sun shaft at intervals, each planetary shaft having a first spiral tooth portion in the middle and two second spiral tooth portions at both ends, the first spiral tooth portion of each planetary shaft meshing with the sun shaft and the internal thread structure on the middle section, the two second spiral tooth portions of each planetary shaft meshing with the sun shaft, and at the same time, the two second spiral tooth portions of each planetary shaft respectively meshing with the annular inner gear ring formed by the two gear block groups;

[0010] Each groove is a dovetail groove, and each groove is provided with an open side on the end surface of the end section away from the middle section. The connecting portion can be inserted into the corresponding groove from the open side. An annular pressure plate is provided at each end of the housing to prevent the connecting portion of the arc-shaped tooth blocks in the two tooth block groups from escaping from the groove from the open side.

[0011] The inner diameter of the annular pressure plate is slightly smaller than the outer diameter of the annular inner gear ring formed by the gear block group to form a limiting shoulder;

[0012] A clip is provided on the connecting part of each arc-shaped tooth block, and a slot that engages with the clip is provided on the side wall of one side of each groove, which is used to limit the radial floating range of the arc-shaped tooth block under normal load. The other side of each groove along the axial direction is an open side and is closed by an annular pressure plate, and each connecting part can move axially in the groove; when the axial load on the arc-shaped tooth block reaches a preset threshold, the connecting part moves axially to disengage the clip from the slot, thereby releasing the restriction on the radial floating of the arc-shaped tooth block, and an elastic reset part is provided between each connecting part and the annular pressure plate, and the elastic reset part is used to provide an elastic reset force in the axial direction to the connecting part.

[0013] Preferably, the connecting portion and the arc-shaped tooth block are integrally formed.

[0014] Preferably, the elastic gasket and the elastic reset member are integrally formed and arranged on the connecting portion.

[0015] Preferably, the elastic gasket and the elastic reset member are made of rubber, silicone or polyurethane.

[0016] Preferably, a buffer gasket and / or a second gap is provided between any two adjacent arc-shaped tooth blocks in each tooth block group.

[0017] Preferably, each spiral tooth of the second spiral tooth portion is provided with a plurality of concave notches at intervals along its extending direction.

[0018] Preferably, both ends of each planetary shaft are passed through a planetary carrier plate, and the planetary carrier plates are respectively arranged in two end sections of the housing.

[0019] One or more technical solutions provided in the present invention have at least the following technical effects or advantages:

[0020] 1. The present invention changes the traditional integral inner gear ring into a plurality of arc-shaped tooth blocks assembled circumferentially, and allows each arc-shaped tooth block to float radially under the action of an elastic reset mechanism, thereby effectively adapting to the meshing deviation caused by gear assembly errors, thermal expansion and transient load fluctuations, and improving the stability and life of the overall meshing; and because each arc-shaped tooth block is reset by an elastic gasket, the meshing rigidity is reduced, so that the reduction mechanism has a certain buffering performance during operation, reduces the gear impact load, helps to reduce meshing noise and reduce tooth surface wear; and the connecting portion of the arc-shaped tooth block is inserted into the groove on the housing, and in some embodiments, a dovetail groove and end face opening structure can be adopted, combined with a pressure plate limit installation, to facilitate the assembly and replacement of the arc-shaped tooth block, and flexible and convenient maintenance operations.

[0021] 2. By providing a buckle on the connecting part of the arc-shaped tooth block and cooperating with the slot provided in the groove, under normal load, the buckle and the slot cooperate to limit the radial floating range of the arc-shaped tooth block, ensuring the meshing accuracy and stability; when subjected to a large axial load (such as the axial component force generated by the spiral teeth), the connecting part releases the clamping restriction under axial movement, releasing the radial floating of the arc-shaped tooth block to buffer the load impact and avoid structural damage. After the load is released, it returns to its original position through the elastic reset member, and has good automatic protection and self-reset capabilities. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a structural schematic diagram of the motor reduction mechanism of the present invention;

[0023] Figure 2 It is a side view of the motor reduction mechanism of the present invention;

[0024] Figure 3 for Figure 2 AA section view in the figure;

[0025] Figure 4 for Figure 3 BB section view in the figure;

[0026] Figure 5 A schematic structural diagram of the housing of the motor reduction mechanism of the present invention;

[0027] Figure 6 Schematic diagram of the structure of the planetary shaft of the motor reduction mechanism of the present invention.

[0028] Explanation of the reference numerals: 10, housing; 11, middle section; 12, end section; 121, first gap; 122, groove; 123, slot; 20, arc-shaped tooth block; 21, connecting portion; 211, buckle; 22, second gap; 30, elastic gasket; 40, annular pressure plate; 50, sun shaft; 60, planetary shaft; 61, first spiral tooth portion; 62, second spiral tooth portion; 621, concave notch; 70, planetary carrier plate; 80, elastic reset member. DETAILED DESCRIPTION

[0029] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0030] like Figures 1 to 6 As shown, the present invention provides a motor reduction mechanism, which includes a housing 10, a gear block group, a sun shaft 50, a plurality of planetary shafts 60 and other supporting components.

[0031] The housing 10 is generally cylindrical and axially divided into three sections: a central section 11 and two end sections 12 located on either side of the central section 11. The inner circumferential wall of the central section 11 is provided with an axially extending internal thread structure for meshing with the first helical tooth portion 61 on the planetary shaft 60, thereby achieving the helical meshing drive function of the central section.

[0032] A number of grooves 122 are evenly arranged along the circumferential direction on the inner peripheral wall of each end section 12. These grooves 122 are preferably dovetail groove structures, and an opening is provided on the end face of the end section 12 away from the middle section 11, so that the connecting portion 21 of the arc-shaped tooth block 20 can be inserted and assembled into the groove 122 from the end face direction. The groove 122 is used to accommodate the connecting portion 21 on the arc-shaped tooth block 20 corresponding thereto. The connecting portion 21 extends radially outward from the outer arc surface of the arc-shaped tooth block 20 and is detachably inserted into the corresponding groove 122. An elastic gasket 30 is provided between the connecting portion 21 and the bottom surface of the groove 122 to provide a radially inward elastic reset force so that the arc-shaped tooth block 20 has radial floating ability.

[0033] Furthermore, if Figure 4 As shown, a first gap 121 is provided between the connecting portion 21 and the groove 122, so that the arc-shaped tooth block 20 is in an internal pressure floating state under a non-load state, which can compensate for the manufacturing error, thermal expansion or small displacement caused by load fluctuations during the gear meshing process, effectively reduce the meshing noise and extend the service life of the tooth surface.

[0034] Each end section 12 is equipped with a tooth block assembly, each consisting of several arcuate tooth blocks 20 assembled to form an annular inner gear ring. These arcuate tooth blocks 20 are assembled through high-precision machining of their end faces to form a continuous meshing surface, which meshes with the second helical tooth portion 62 on the corresponding planetary shaft 60.

[0035] An annular pressure plate 40 is provided on each end surface of the housing 10. The inner diameter of the annular pressure plate 40 is slightly smaller than the outer diameter of the inner gear ring formed by the gear block assembly, thereby forming a limiting shoulder in the structure to prevent the connecting portion 21 and the arcuate gear block 20 from escaping from the groove 122. The annular pressure plate 40 can be fastened by thread or snap-on installation to facilitate subsequent maintenance.

[0036] In a preferred embodiment, a buckle 211 is provided on the connecting portion 21, and a matching slot 123 is provided on the side wall of the groove 122. The matching structure of the buckle 211 and the slot 123 limits the axial movement of the connecting portion 21 under normal working conditions, thereby limiting the radial floating stroke of the arc-shaped tooth block 20. When subjected to an axial load exceeding a preset threshold (for example, due to the meshing tooth design, a significant axial component force is generated during the rapid start-stop process), the buckle 211 can be disengaged from the slot 123, causing the connecting portion 21 to undergo axial displacement, thereby releasing the floating restriction of the arc-shaped tooth block 20 and allowing it to obtain a larger radial avoidance space to release its radial degree of freedom to absorb the meshing offset. This adaptive unlocking floating structure can effectively alleviate the meshing impact under sudden load scenarios and protect the operating safety and life of the gear system.

[0037] The connecting portion 21 and the curved tooth block 20 are preferably formed in one piece to improve overall structural strength and processing consistency. In another alternative, the connecting portion 21 can be made as an independent part and fixedly connected to the curved tooth block 20 by means of a keyway, screws, etc., to facilitate quick replacement or local repair.

[0038] In a further embodiment, the elastic gasket 30 and the elastic return member 80 can be designed as an integrally formed elastic return assembly. The elastic return assembly can be made of a flexible polymer material such as rubber, silicone, or polyurethane, exhibiting excellent fatigue life and damping performance. This elastic return assembly provides radial return under normal operating conditions and, when the buckle 211 and slot 123 structure are unlocked, also provides axial elastic cushioning, achieving bidirectional, controllable, and flexible support.

[0039] In order to enhance the overall splicing stability between the arc-shaped tooth blocks 20, a buffer gasket may be provided or a second gap 22 may be retained between any two adjacent arc-shaped tooth blocks 20 to prevent the splicing stress from being transmitted between the arc-shaped tooth blocks 20, thereby improving the noise control effect and enhancing the system's adaptability to thermal expansion.

[0040] The planetary shafts 60 are evenly arranged around the sun shaft 50. Figure 6 As shown, each planetary shaft 60 has a central first helical tooth section 61 for meshing with the sun shaft 50 and the internal thread structure of the intermediate section 11. Second helical tooth sections 62 are located at each end of each planetary shaft 60, meshing with the two tooth block groups, respectively. To enhance lubrication and meshing flexibility, each helical tooth on the second helical tooth section 62 is provided with a number of recessed notches 621 spaced along its extension, forming an interrupted tooth structure. This creates an oil film-retaining cavity and chip clearance, enhancing meshing lubrication and operational stability.

[0041] Both ends of each planetary shaft 60 are inserted into the planetary carrier plate 70 , which is fixedly mounted in the two end sections 12 of the housing 10 and serves as an output component for torque transmission and load support, providing a symmetrical arrangement and dynamic balance for the system.

[0042] In summary, the motor reduction mechanism of the present invention achieves structural high-tolerance meshing capability and dynamic impact mitigation function by introducing a floating gear block group into a fixed inner ring gear structure, combined with an elastic reset component, an adaptive unlocking structure and an intermittent tooth planetary shaft design. It is suitable for high-precision and high-reliability driving scenarios such as smart door control, automatic curtains, robot joints and industrial automation.

[0043] This specification and drawings are merely illustrative of the present application and are intended to cover any and all modifications, variations, combinations, or equivalents within the scope of this application. Obviously, those skilled in the art may make various modifications and variations to this application without departing from the scope of this application. Thus, this application is intended to include such modifications and variations as fall within the scope of this application and its equivalents.

Claims

1. A motor reduction mechanism, characterized in that: include: A cylindrical shell (10) is axially divided into a middle section (11) located in the middle and two end sections (12) located on both sides of the middle section (11), wherein the middle section (11) is provided with an axially extending internal thread structure, and the inner peripheral wall of each end section (12) is provided with a plurality of grooves (122) distributed at intervals along the circumferential direction; Two tooth block groups are respectively arranged in two end sections (12), each tooth block group includes a plurality of arc-shaped tooth blocks (20) that can be circumferentially spliced ​​to form an annular inner gear ring structure for meshing, a connecting portion (21) extending radially outward is provided on the outer arc surface of each arc-shaped tooth block (20), the connecting portion (21) is inserted into a groove (122) arranged in a one-to-one correspondence therewith, and an elastic gasket (30) is provided between the connecting portion (21) and the bottom surface of the groove (122), a first gap (121) is provided between the outer arc surface of each arc-shaped tooth block (20) and the inner peripheral wall of the corresponding end section (12) to allow the arc-shaped tooth block (20) to float in the radial direction, and the elastic gasket (30) is used to provide a radially inward elastic reset force to the arc-shaped tooth block (20); a sun shaft (50) which axially penetrates the housing (10) and can be driven to rotate by a motor; A plurality of planetary shafts (60) are arranged at intervals around the sun shaft (50), each planetary shaft (60) is provided with a first spiral tooth portion (61) in the middle and two second spiral tooth portions (62) at both ends, the first spiral tooth portion (61) of each planetary shaft (60) is meshed with the sun shaft (50) and the internal thread structure on the middle section (11), the two second spiral tooth portions (62) of each planetary shaft (60) are meshed with the sun shaft (50), and at the same time, the two second spiral tooth portions (62) of each planetary shaft (60) are respectively meshed with the annular inner gear ring formed by the two gear block groups; Each groove (122) is a dovetail groove. Each groove (122) is provided with an open side on an end surface of the end section (12) away from the middle section (11). The connecting portion (21) can be inserted into the corresponding groove (122) from the open side. An annular pressure plate (40) is provided at each end of the housing (10) to prevent the connecting portion (21) of the arc-shaped tooth blocks (20) in the two tooth block groups from escaping from the groove (122) from the open side. The inner diameter of the annular pressure plate (40) is slightly smaller than the outer diameter of the annular inner gear ring formed by the gear block group, so as to form a limiting shoulder; A buckle (211) is provided on the connecting portion (21) of each arc-shaped tooth block (20), and a clamping groove (123) is provided on the side wall of one side of each groove (122) to be clamped with the buckle (211) for limiting the radial floating range of the arc-shaped tooth block (20) under normal load. The other side of each groove (122) along the axial direction is an open side and is closed by the annular pressure plate (40). Each connecting portion (21) can move axially in the groove (122) in which it is located; when the axial load on the arc-shaped tooth block (20) reaches a preset threshold, the connecting portion (21) moves axially to disengage the buckle (211) from the clamping groove (123), thereby releasing the restriction on the radial floating of the arc-shaped tooth block (20), and an elastic reset member (80) is provided between each connecting portion (21) and the annular pressure plate (40), and the elastic reset member (80) is used to provide an elastic reset force in the axial direction to the connecting portion (21).

2. The motor reduction mechanism according to claim 1, characterized in that: The connecting portion (21) and the arc-shaped tooth block (20) are integrally formed.

3. The motor reduction mechanism according to claim 1, characterized in that: The elastic gasket (30) and the elastic reset member (80) are integrally formed and arranged on the connecting portion (21).

4. The motor reduction mechanism according to claim 3, characterized in that: The elastic gasket (30) and the elastic reset member (80) are made of rubber, silicone or polyurethane material.

5. The motor reduction mechanism according to claim 1, characterized in that: A buffer pad and / or a second gap (22) is provided between any two adjacent arc-shaped tooth blocks (20) in each tooth block group.

6. The motor reduction mechanism according to claim 1, characterized in that: Each spiral tooth of the second spiral tooth portion (62) is provided with a plurality of concave notches (621) at intervals along its extension direction.

7. The motor reduction mechanism according to claim 1, characterized in that: Both ends of each planetary shaft (60) are passed through a planetary carrier plate (70), and the planetary carrier plate (70) is respectively arranged in two end sections (12) of the housing (10).

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