Large hollow shaft cycloid joint module

Abstract

The utility model discloses a large hollow shaft cycloid joint module, which comprises a shell, a hollow shaft and a cycloid joint, the eccentric crankshaft is arranged in the mounting space of the shell in a penetrating manner and is provided with an eccentric structure; the output end cover is arranged on the outer side of the eccentric crankshaft in a sleeving mode, and a first needle bearing is arranged between the eccentric crankshaft and the output end cover. The first cycloid gear assembly comprises a first cycloid gear and a first inner gear, the first cycloid gear is arranged on the outer side of the eccentric crankshaft in a sleeving mode through a second needle bearing, and the first inner gear is formed on the inner side face of the output end cover; the second cycloid gear assembly comprises a second cycloid gear and a second inner gear, the second cycloid gear is fixedly arranged at the bottom of the outer side of the first cycloid gear in a sleeving mode, and the second inner gear is formed on the inner wall of the shell; the eccentric balance weight wheel is fixedly arranged on the outer side of the eccentric crankshaft in a sleeving mode. The hollow shaft is fixedly arranged in the eccentric crankshaft in a penetrating mode, and a cable channel is formed in the hollow shaft. Through layout optimization of the cycloid gear and the bearing, the problems of poor rigidity and low precision in the prior art are solved.

Description

Technical Field

[0001] This utility model relates to the field of robotics technology, and in particular to a large hollow shaft cycloidal joint module. Background Technology

[0002] Currently, robots need to meet two key technical requirements in their joint modules: large hollow shafts and high rigidity. Large hollow shafts are used to accommodate various cables to meet the robot's complex wiring needs, such as power, signal, and data lines, while high rigidity is necessary to meet the robot's requirements for control precision.

[0003] There are two main solutions for existing robot joint modules: harmonic drive modules and cycloidal drive modules. Existing harmonic drive modules have the advantage of large hollow shafts, which can meet complex wiring requirements, but their structural limitations result in lower rigidity, making them unsuitable for high-precision control. Existing cycloidal reducers, due to their cycloidal gear design, have high rigidity and precision, but their design characteristics prevent them from being adapted to large hollow shafts, thus making them unsuitable for applications requiring extensive wiring. Therefore, existing robot joint modules suffer from a limitation in functionality. Utility Model Content

[0004] The technical problem to be solved by this utility model is to provide a large hollow shaft cycloidal joint module, which achieves a large hollow shaft design and improves rigidity through structural optimization, thereby taking into account both the flexibility of the wire routing and the precision of motion control, and can solve the problem of the previous single function.

[0005] To address the aforementioned technical problems, this utility model discloses a large hollow shaft cycloidal joint module, comprising a housing with an internal installation space; an eccentric crankshaft passing through the installation space of the housing, the eccentric crankshaft having an eccentric structure for transmitting power and driving the cycloidal gear; an output end cover fitted onto the outside of the eccentric crankshaft, a first needle roller bearing between the eccentric crankshaft and the output end cover to allow the output end cover to rotate around the eccentric crankshaft, and an angular contact ball bearing between the output end cover and the housing; and a first cycloidal gear assembly including a first cycloidal gear and a first internal gear, the first cycloidal gear being fitted onto the outside of the eccentric crankshaft via a second needle roller bearing to allow the first cycloidal gear to rotate on its own axis and revolve around its axis, the first internal gear being formed on the output end cover. The inner side has a first internal gear meshing with the outer bottom of the first cycloidal gear, so that the first internal gear drives the output end cover to rotate; the second cycloidal gear assembly includes a second cycloidal gear and a second internal gear, the second cycloidal gear is fixedly sleeved on the outer bottom of the first cycloidal gear, so that when the first cycloidal gear rotates and revolves around the axis, it drives the second cycloidal gear to rotate and revolve around the axis, the second internal gear is formed on the inner wall of the outer casing to limit the movement trajectory of the second cycloidal gear; the eccentric counterweight wheel is fixedly sleeved on the outer side of the eccentric crankshaft, used to compensate for the inertial torque generated by the eccentric structure and the movement of the cycloidal gear; the hollow shaft is fixedly inserted inside the eccentric crankshaft, and the interior of the hollow shaft forms a cable channel for accommodating power lines, signal lines and data lines.

[0006] The housing contains a bearing housing fixedly installed in the middle. A third needle roller bearing is provided between the bearing housing and the eccentric crankshaft, which is sleeved on the outside of the eccentric crankshaft, so that the eccentric crankshaft can rotate relative to the housing.

[0007] The rotor assembly is fixedly mounted at the bottom of the eccentric crankshaft, and the rotor assembly is located inside the housing.

[0008] The top of the output end cover is fixedly equipped with an output flange, and the middle of the output flange has a through hole that communicates with the hollow shaft.

[0009] The outer casing includes a fixed flange, an upper housing, a lower housing, and a motor bearing bracket, which are fixedly connected from top to bottom, with the bearing housing clamped between the upper housing and the lower housing.

[0010] The bottom of the first cycloidal gear extends radially to form a retaining part, and the outer peripheral side of the retaining part is formed with a plurality of retaining teeth arranged continuously in the circumferential direction. The inner side wall of the second cycloidal gear is formed with a plurality of retaining grooves arranged continuously in the circumferential direction. In the assembled state, the retaining teeth are inserted into the retaining grooves.

[0011] Among them, the eccentric structure is an eccentric wheel fitted on an eccentric crankshaft or an eccentric shaft segment formed on an eccentric crankshaft.

[0012] Among them, the tooth profiles of the first cycloidal gear, the first internal gear, the second cycloidal gear, and the second internal gear are cycloidal teeth or involute teeth.

[0013] The inner wall of the cable channel is equipped with an isolation and protective layer.

[0014] The eccentric counterweight wheel has a mounting hole through which the eccentric crankshaft passes. The wall of the mounting hole extends radially inward to form a locking protrusion. The outer circumferential side of the eccentric crankshaft has a limiting groove for the locking protrusion to be inserted.

[0015] Compared with the prior art, the embodiments of this utility model have the following beneficial effects:

[0016] (1) By optimizing the layout of the cycloidal gear and bearing, the rigidity of the module is significantly improved, supporting high-precision control and solving the problems of poor rigidity and low precision in the past.

[0017] (2) The volume of the hollow shaft is increased by more than 30%, which meets the needs of complex wiring of multiple cables and solves the problem of cable routing obstruction in the past;

[0018] (3) The eccentric counterweight effectively compensates for the inertia imbalance, reduces vibration, and extends service life. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the joint module in this utility model;

[0021] Figure 2 This is an exploded view of the joint module in this utility model;

[0022] Figure 3 This is an exploded view of the outer shell of this utility model;

[0023] Figure 4 This is a cross-sectional view of the joint module in this utility model;

[0024] Figure 5 A schematic diagram of the eccentric crankshaft in this utility model;

[0025] Figure 6 A schematic diagram of the output end cap in this utility model;

[0026] Figure 7A schematic diagram of the structure of the first cycloidal gear and the second cycloidal gear after assembly in this utility model;

[0027] Figure 8 This utility model contains a schematic diagram of the eccentric counterweight wheel. Detailed Implementation

[0028] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] The terms "first," "second," etc., in the specification, claims, and accompanying drawings of this utility model are used to distinguish different objects, not to describe a specific order. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, apparatus, product, or server that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products, or servers.

[0030] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of the present invention. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0031] This utility model discloses a specific implementation of a large hollow shaft cycloidal joint module. Please see [link / reference]. Figure 1 and Figure 2 It includes a housing 1, an output flange 21, an output end cover 4, a first cycloidal gear 61 assembly, a second cycloidal gear 62 assembly, an eccentric crankshaft 3, a hollow shaft 9, and a rotor assembly 22. An installation space is formed inside the housing 1, and the output flange 21, output end cover 4, first cycloidal gear 61 assembly, second cycloidal gear 62 assembly, eccentric crankshaft 3, hollow shaft 9, and rotor assembly 22 are all installed within this installation space inside the housing 1.

[0032] Combination Figure 3The outer casing 1 includes a fixed flange 11, an upper housing 12, a bearing seat 13, a lower housing 14, and a motor bearing bracket 15, which are fixedly connected from top to bottom. The bearing seat 13 is clamped between the upper housing 12 and the lower housing 14. Optionally, the sequential connection can be achieved by screws, which facilitates the disassembly, assembly, and maintenance of the module.

[0033] Combination Figure 4 and Figure 5 An eccentric crankshaft 3 is installed in the mounting space of the housing 1. The eccentric crankshaft 3 is provided with an eccentric structure 31, which is used to transmit power and drive the cycloidal gear. In this embodiment, the eccentric structure 31 is an eccentric shaft segment formed on the eccentric crankshaft 3. In other embodiments, the eccentric structure 31 may also be an eccentric wheel sleeved on the eccentric crankshaft 3.

[0034] Combination Figure 4 and Figure 6 The output end cover 4 is sleeved on the outside of the eccentric crankshaft 3. A first needle roller bearing 51 is provided between the eccentric crankshaft 3 and the output end cover 4. An angular contact ball bearing 54 is provided between the output end cover 4 and the outer shell 1 so that the output end cover 4 can rotate around its own axis. An output flange 21 for connecting with an external module is fixedly installed on the top of the output end cover 4. When the output end cover 4 rotates, it will drive the output flange 21 to rotate, thereby realizing the output of power.

[0035] Combination Figure 4 , Figure 6 and Figure 7 The first cycloidal gear assembly 61 includes a first cycloidal gear 61 and a first internal gear 71. The first cycloidal gear 61 is sleeved on the outside of the eccentric crankshaft 3 via a second needle roller bearing 52. This can be understood as the outer surface of the second needle roller bearing 52 being in close contact with the inner surface of the first cycloidal gear 61, and the inner surface of the second needle roller bearing 52 being in close contact with the outer surface of one end of the eccentric crankshaft 3, allowing the first cycloidal gear 61 to rotate on its own axis and revolve around its axis. The first internal gear 71 is formed on the inner surface of the output end cover 4. This can be understood as a first internal gear ring being formed on the inner surface of the output end cover 4, and the first internal gear 71 meshes with the outer bottom of the first cycloidal gear 61, causing the first internal gear 71 to drive the output end cover 4 to rotate, thus realizing power output.

[0036] Combination Figure 3 , Figure 4 and Figure 7 The second cycloidal gear assembly 62 includes a second cycloidal gear 62 and a second internal gear 72. The second cycloidal gear 62 is fixedly sleeved on the outer bottom of the first cycloidal gear 61, so that when the first cycloidal gear 61 rotates and revolves around its axis, it drives the second cycloidal gear 62 to rotate and revolve around its axis. Please see... Figure 3The second internal gear 72 is formed on the inner wall of the outer casing 1. It can be understood that the inner wall of the outer casing 1 is provided with a second internal gear ring. The second internal gear 72 meshes with the second cycloidal gear 62 and can limit the movement trajectory of the second cycloidal gear 62.

[0037] In this embodiment, please see Figure 7 The bottom of the first cycloidal gear 61 extends radially to form a retaining part. The outer peripheral side of the retaining part has a plurality of retaining teeth 63 arranged continuously in the circumferential direction. The inner side wall of the second cycloidal gear 62 has a plurality of retaining grooves 64 arranged continuously in the circumferential direction. In the assembled state, the retaining teeth 63 are inserted into the retaining grooves 64 so that the first cycloidal gear 61 and the second cycloidal gear 62 can be rigidly connected, which can effectively improve the rigidity.

[0038] Please see Figure 3 An eccentric counterweight wheel 8 is fixedly sleeved on the outside of the eccentric crankshaft 3 to compensate for the inertial torque generated by the movement of the eccentric structure 31 and the cycloidal gear. A hollow shaft 9 is fixedly inserted inside the eccentric crankshaft 3. The interior of the hollow shaft 9 forms a cable channel to accommodate power lines, signal lines, and data lines. In addition, a through hole communicating with the hollow shaft 9 is opened in the middle of the output flange 21. To improve service life, the inner wall of the cable channel is provided with an isolation protective layer to prevent the cables from contacting moving parts.

[0039] In this embodiment, please see Figure 4 The bearing housing 13 is fixedly installed in the middle position inside the housing 1. A third needle roller bearing 53 is provided between the bearing housing 13 and the eccentric crankshaft 3, which is sleeved on the outside of the eccentric crankshaft 3, so that the eccentric crankshaft 3 can rotate relative to the housing 1. The rotor assembly 22 is fixedly installed at the bottom of the eccentric crankshaft 3, and the rotor assembly 22 is located inside the housing 1.

[0040] As a preferred embodiment, the tooth profiles of the first cycloidal gear 61, the first internal gear 71, the second cycloidal gear 62, and the second internal gear 72 are cycloidal teeth or involute teeth. See [link / reference]. Figure 8 The eccentric counterweight wheel 8 has a mounting hole 81 through which the eccentric crankshaft 3 passes. The diameter of the mounting hole 81 is larger than the outer diameter of the first cycloidal gear 61. Figure 5 and Figure 8 The mounting hole 81 extends radially inward to form a locking protrusion 82. The outer peripheral side of the eccentric crankshaft 3 is provided with a limiting groove 32 for the locking protrusion 82 to be inserted. The cooperation between the locking protrusion 82 and the limiting groove 32 can play a role in preventing mistaken installation and facilitate installation. In addition, it can also limit the offset of the eccentric counterweight wheel 8 relative to the eccentric crankshaft 3 and ensure working accuracy.

[0041] The transmission process of the large hollow shaft cycloidal joint module in this embodiment is as follows: An external power source (such as a servo motor) drives the eccentric crankshaft 3 to rotate. The eccentric structure 31 on the eccentric crankshaft 3 drives the first cycloidal gear 61 and the second cycloidal gear 62 to revolve around the axis of the eccentric crankshaft 3. Due to the presence of the eccentric structure 31, the cycloidal gears rotate simultaneously while revolving. Since the second internal gear 72 (second internal gear ring) is fixed on the outer shell 1 and meshes with the external teeth of the second cycloidal gear 62, it restricts the movement trajectory of the second cycloidal gear 62. The first cycloidal gear 61 is mounted on the eccentric crankshaft 3 through a needle roller bearing. The first cycloidal gear 61 can rotate freely around its axis. The output end cover 4 is mounted in the outer shell 1 through an angular contact bearing, and the first internal gear 71 (first internal gear ring) is opened on the inner side wall of the output end cover 4. The revolution and rotation of the first cycloidal gear 61 drive the output end cover 4 to rotate around its axis through tooth meshing. The rotation of the output end cover 4 is transmitted to the external robot joint to realize power output. Due to the high reduction ratio of cycloidal gears, the output speed is significantly reduced, while the torque is greatly increased.

[0042] In this embodiment, the large hollow shaft cycloidal joint module has a hollow shaft 9 running through the entire module. The internal space accommodates power lines, signal lines, and data lines. During transmission, the cables bend freely with the joint movement, avoiding limitations on robot flexibility caused by wiring constraints. The eccentric balance block on the eccentric crankshaft 3 uses reverse mass balancing to counteract the inertial torque generated by the eccentric structure 31 and the cycloidal gear movement, reducing vibration and ensuring smooth and accurate transmission. Through optimized layout of the cycloidal gear and bearings, the module's rigidity is significantly improved, supporting high-precision control and solving the previous problems of poor rigidity and low precision.

[0043] Finally, it should be noted that the large hollow shaft cycloidal joint module disclosed in this utility model embodiment is only a preferred embodiment of this utility model and is only used to illustrate the technical solution of this utility model, not to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the various embodiments of this utility model.

Claims

1. A large hollow shaft cycloidal joint module, characterized in that, include: The outer casing has an internal space for installation. An eccentric crankshaft, which passes through the mounting space of the housing, is provided with an eccentric structure; An output end cover is sleeved on the outside of the eccentric crankshaft. A first needle roller bearing is provided between the eccentric crankshaft and the output end cover, and an angular contact ball bearing is provided between the output end cover and the outer shell. The first cycloidal gear assembly includes a first cycloidal gear and a first internal gear. The first cycloidal gear is sleeved on the outside of the eccentric crankshaft via a second needle roller bearing. The first internal gear is formed on the inner side of the output end cover and meshes with the outer bottom of the first cycloidal gear. The second cycloidal gear assembly includes a second cycloidal gear and a second internal gear. The second cycloidal gear is fixedly sleeved on the outer bottom of the first cycloidal gear, and the second internal gear is formed on the inner wall of the housing. An eccentric counterweight wheel is fixedly sleeved on the outside of the eccentric crankshaft; A hollow shaft is fixedly inserted inside the eccentric crankshaft, and a cable channel is formed inside the hollow shaft.

2. The large hollow shaft cycloidal joint module according to claim 1, characterized in that, A bearing housing is fixedly installed in the middle of the housing. A third needle roller bearing is provided between the bearing housing and the eccentric crankshaft, which is sleeved on the outside of the eccentric crankshaft, so that the eccentric crankshaft can rotate relative to the housing.

3. A large hollow shaft cycloidal joint module according to claim 1 or 2, characterized in that, A rotor assembly is fixedly mounted on the bottom of the eccentric crankshaft, and the rotor assembly is located inside the housing.

4. A large hollow shaft cycloidal joint module according to claim 1 or 2, characterized in that, An output flange is fixedly installed on the top of the output end cover, and a through hole communicating with the hollow shaft is opened in the middle of the output flange.

5. A large hollow shaft cycloidal joint module according to claim 2, characterized in that, The outer casing includes a fixed flange, an upper housing, a lower housing, and a motor bearing bracket, which are fixedly connected from top to bottom, and the bearing seat is clamped between the upper housing and the lower housing.

6. A large hollow shaft cycloidal joint module according to claim 1, characterized in that, The bottom of the first cycloidal gear extends radially to form a retaining portion, and the outer peripheral side of the retaining portion is formed with a plurality of retaining teeth arranged continuously in the circumferential direction. The inner sidewall of the second cycloidal gear is formed with a plurality of retaining grooves arranged continuously in the circumferential direction. In the assembled state, the retaining teeth are inserted into the retaining grooves.

7. A large hollow shaft cycloidal joint module according to claim 1, characterized in that, The eccentric structure is an eccentric wheel fitted on the eccentric crankshaft or an eccentric shaft segment formed on the eccentric crankshaft.

8. A large hollow shaft cycloidal joint module according to claim 1, characterized in that, The tooth profiles of the first cycloidal gear, the first internal gear, the second cycloidal gear, and the second internal gear are cycloidal teeth or involute teeth.

9. A large hollow shaft cycloidal joint module according to claim 1, characterized in that, The inner wall of the cable channel is provided with an isolation and protective layer.

10. A large hollow shaft cycloidal joint module according to claim 1, characterized in that, The eccentric counterweight wheel has a mounting hole through which the eccentric crankshaft passes. The wall of the mounting hole extends radially inward to form a locking protrusion. The outer peripheral side of the eccentric crankshaft has a limiting groove for the locking protrusion to be inserted.

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