Compact planetary cycloid joint module

Abstract

The invention discloses a compact type planet cycloid joint module. The compact type planet cycloid joint module comprises a first-stage planet wheel speed reducing mechanism, a second-stage cycloid pin wheel speed reducing mechanism and a driving component. A hollow eccentric input shaft of the second-stage cycloidal-pin wheel speed reducing mechanism serves as an output shaft of the first-stage planet wheel speed reducing mechanism, and coaxial transmission is achieved. The hollow eccentric input shaft of the second-stage cycloidal-pin wheel speed reducing mechanism and the output shaft of the first-stage planet wheel speed reducing mechanism share one shaft, so that the axial size of the joint module is small, the module is compact, and the rigidity is improved; an output shaft of a first-stage planet wheel speed reducing mechanism is reduced, meanwhile, a large-diameter hollow eccentric input shaft is adopted, and the weight of the joint module is reduced.

Description

Technical Field

[0001] The invention relates to a mechanical transmission mechanism, and in particular to a joint module used as a collaborative robot and a humanoid robot. Background Art

[0002] The joint module is the core component of collaborative robots and humanoid robots, which determines the performance and life of the robot. The joint modules on the current market are composed of a drive part and a reducer part axially connected, mainly planetary reducer joint modules, harmonic joint modules, and cycloid joint modules. Planetary joint modules and cycloid joint modules have a small reduction ratio, that is, the reduction ratio of planetary joint modules is generally within 20, while the reduction ratio of cycloid joint modules is within 40. In addition, the longitudinal and axial dimensions of the joint module are large, the hollow diameter of the shaft is small, and it is not easy to use; the harmonic joint module has the disadvantages of insufficient rigidity, poor impact resistance, and low power density. In addition, there is a hollow RV reducer joint module. The RV reducer is a high-precision transmission device consisting of a planetary gear reducer front stage and a cycloid pinwheel reducer rear stage. The transmission machinery with self-locking function under certain conditions is one of the most commonly used reducers. It has the characteristics of large transmission ratio, low vibration, low noise and low energy consumption, so it is widely used in mechanical reduction devices of production process equipment in various industries. In order to further achieve a large reduction ratio, there is also a three-stage rotating joint module formed by axially connecting the RV reducer to a planetary gear assembly and a driving part. Although the RV reducer joint module, or the three-stage rotating joint module formed by axially connecting the RV reducer to a planetary gear assembly and a driving part has a large reduction ratio, the "RV reducer" and "planetary gear assembly" of this structure are separate independent components, and then axially connected to form a joint module. This results in an increase in the axial length of the joint module, a decrease in support stiffness, poor coaxiality, a small hollow diameter, etc., which affects the performance and life of the joint module.

[0003] Therefore, this field needs to design a joint module with a more compact structure, lighter weight, higher rigidity and larger hollow diameter to meet the current market demand. Summary of the invention

[0004] In order to solve the technical problems that the joint module structure is not compact enough, the rigidity is not high, and the hollow diameter of the shaft is not large, the present invention provides a compact planetary cycloid joint module with a more compact structure, light weight, higher rigidity, and a large hollow diameter of the shaft.

[0005] The present invention provides a compact planetary cycloid joint module, comprising a first-stage planetary gear reduction mechanism, a second-stage cycloid pinwheel reduction mechanism and a driving component, characterized in that the hollow eccentric input shaft of the second-stage cycloid pinwheel reduction mechanism is used as the output shaft of the first-stage planetary gear reduction mechanism, that is, the two reduction mechanisms are coaxially driven. The hollow eccentric input shaft of the second-stage cycloid pinwheel reduction mechanism and the output shaft of the first-stage planetary gear reduction mechanism share a common shaft, so that the axial dimension of the joint module is small, the module is compact, and the rigidity is improved; the output shaft of the first-stage planetary gear reduction mechanism is reduced, and the weight of the module is reduced.

[0006] Preferably, the first-stage planetary gear reduction mechanism comprises an axially flat sun gear and an internal gear, an axially flat planetary gear disposed between the sun gear and the internal gear, and an axially flat planetary disc connected to the planetary gear pin, wherein the planetary disc is connected to one end of the hollow eccentric input shaft for transmission. The overall axial structure of the first-stage planetary gear reduction mechanism is made axially flat, and in particular, the output member is made into an axially flat planetary disc. Moreover, one end of the hollow eccentric input shaft of the second-stage cycloid pinwheel reduction mechanism is axially embedded in the planetary disc, so that the axial dimension of the joint module is small, the module is compact, the rigidity is improved, the weight is reduced, and the transmission is reliable.

[0007] Preferably, the planetary disc and one end of the hollow eccentric input shaft are connected and driven by a spline. The two components are connected and driven by a coaxial spline, which is convenient to install and has high transmission rigidity and reliability.

[0008] Preferably, the planetary disc and one end of the hollow eccentric input shaft are connected and driven by threads. The two components are connected and driven by coaxial threads, which is simple to manufacture and install and has reliable transmission.

[0009] Preferably, the planetary disc and one end of the hollow eccentric input shaft are connected and driven by interference fit. The two components are connected and driven by coaxial interference fit, which is simple to manufacture and has strong adaptability.

[0010] Preferably, the rotating shaft of the sun gear is a hollow shaft and is coaxially driven with the output shaft of the driving component. The input shaft of the first-stage planetary gear reduction mechanism and the output shaft of the driving component share a common shaft, so that the axial dimension of the joint module is small, the module is compact, and the rigidity is improved; the input shaft of the first-stage planetary gear reduction mechanism is reduced, and the weight of the module is reduced.

[0011] Preferably, the second-stage cycloid pinwheel reduction mechanism comprises a pin-cycloid meshing mechanism disposed on the hollow eccentric input shaft, plate-shaped output connection components disposed on both sides of the pin-cycloid meshing mechanism, and a fixed connection component disposed on the outer circle of the output connection component. The plate-shaped structure is used as the output connection component, so that the axial size of the second-stage cycloid pinwheel reduction mechanism is reduced, the structure is compact, the weight is light, and the rigidity is improved.

[0012] Preferably, the driving component is a frameless torque motor, the shaft of which is coaxial with the hollow shaft of the sun gear of the first-stage planetary gear reduction mechanism, and the rotor of the frameless torque motor is arranged on the hollow shaft. The shaft of the motor and the input shaft of the first-stage planetary gear reduction mechanism share the same shaft, so that the axial size of the joint module is reduced, the structure is compact, the weight is light, and the rigidity is improved.

[0013] Preferably, the hollow eccentric input shaft is a large diameter hollow shaft, wherein the hollow diameter is larger than the diameter of the hollow shaft of the sun gear. The hollow eccentric input shaft is made into a large diameter hollow shaft, which not only facilitates wiring, but also greatly reduces the weight of the shaft, which is conducive to lightweighting of the product.

[0014] Preferably, the first-stage planetary gear reduction mechanism is a multi-stage planetary gear reduction mechanism or a multi-stage NGW mechanism. The present invention can use a variety of planetary gear reduction structures connected with the second-stage cycloid pinwheel reduction mechanism to form a joint module, which is suitable for various working conditions.

[0015] A single cycloid pinwheel reduction mechanism is a transmission mechanism with a small tooth difference in which multiple teeth are engaged. It has the characteristics of large reduction ratio, stable transmission and good rigidity. However, its transmission ratio is generally between 30 and 50, which is difficult to meet the large reduction ratio requirements of humanoid robots and collaborative robots. It is necessary to superimpose a first-stage reduction ratio mechanism to meet the requirements of large reduction ratio. The present invention adopts a planetary gear reduction mechanism as the first stage and superimposes it with a cycloid pinwheel reduction mechanism to meet the requirements of large reduction ratio, large meshing rigidity, stable transmission and low noise. Mainly, each part of the planetary gear reduction mechanism adopts an axially flattened structural design, especially the output member is set as an axially flat planetary disc, which has high rigidity and small axial size. The input shaft of the cycloid pinwheel reduction mechanism and the output shaft of the planetary gear reduction mechanism share a shaft transmission structure, omitting the output shaft of the planetary gear reduction mechanism. At the same time, the planetary disc and the hollow eccentric input shaft are connected and driven by splines, threads or interference fits, and the structure is simple and the axial connection size is short. In addition, the input shaft of the planetary gear reduction mechanism, that is, the rotating shaft of the sun gear, and the output shaft of the frameless torque motor share a shaft. That is, a cycloidal pinwheel reduction mechanism and a planetary gear reduction mechanism are axially embedded, and a planetary gear reduction mechanism and a frameless motor are axially embedded in a structural manner, thereby reducing the axial size of the entire shutdown module. Moreover, the first-stage planetary gear reduction mechanism and the driving component omit the outer shell of the original independent components, and the radial size is reduced; the hollow eccentric input shaft is a large-diameter hollow shaft, and the hollow diameter is larger than the diameter of the hollow shaft of the sun gear. In addition to facilitating wiring, the large-diameter hollow structure can also reduce the weight of the joint module. As a result, the structure of the present invention is more compact, light in weight, strong in supporting rigidity, high in assembly coaxiality, low in noise, more stable in operation, high in torque density, long in life, and more competitive. The present invention is used as a miniaturized joint module, which can meet the requirements of miniaturization, large hollow, high rigidity, and high life. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A three-dimensional diagram of an embodiment of a joint module of the present invention;

[0017] Figure 2 for Figure 1 A cross-sectional view of

[0018] Figure 3 It is a cross-sectional view of the cycloid pinwheel reduction mechanism in the joint module of the present invention;

[0019] Figure 4 It is a cross-sectional view of the planetary gear reduction mechanism in the joint module of the present invention;

[0020] Figure 5 for Figure 4 A stereoscopic diagram of the right projection;

[0021] Figure 6 for Figure 4A three-dimensional diagram of the left projection;

[0022] Figure 7 A three-dimensional diagram of a planetary disk of a planetary gear reduction mechanism;

[0023] Figure 8 A three-dimensional diagram of the large diameter hollow eccentric input shaft of the cycloid pinwheel reduction mechanism.

[0024] In the figure:

[0025] 1- Second stage cycloid pinwheel reduction mechanism;

[0026] 11-needle swing engagement mechanism;

[0027] 12-Hollow eccentric input shaft;

[0028] 13- output connection component;

[0029] 14-Fixed connecting parts;

[0030] 2-First stage planetary gear reduction mechanism;

[0031] 21- planetary gear pin;

[0032] 22-planetary disk;

[0033] 23- planetary gear;

[0034] 24-internal gear;

[0035] 25-Sun gear;

[0036] 26-hollow shaft;

[0037] 3-Frameless torque motor;

[0038] 4- Dust cover. DETAILED DESCRIPTION

[0039] In order to make the purpose, technical solution and advantages of the present invention clearer, the present invention is described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the following specific embodiments are only used to explain the present invention and do not constitute a limitation to the present invention.

[0040] As attached Figure 1 , Figure 2 As shown, the present invention provides a compact planetary cycloid joint module, comprising a second-stage cycloid pinwheel reduction mechanism 1, a first-stage planetary gear reduction mechanism 2, a driving component 3 and a dust cover 4, which are axially connected in sequence. Figure 3The second-stage cycloid pinwheel reduction mechanism 1 comprises a hollow eccentric input shaft 12, a pin-swing meshing mechanism 11 arranged on the hollow eccentric input shaft 12, and output connection components 13 arranged on both sides of the pin-swing meshing mechanism 11. The pin-swing meshing mechanism 11 is connected to the plate-shaped output connection components 13 on both sides through a plurality of annularly arranged pins. When the hollow eccentric input shaft 12 rotates, the output connection component 13 is driven to rotate through the pin-swing meshing mechanism 11 to output power. A fixed connection component 14 is provided on the outer circle of the output connection component 13.

[0041] like Figure 2 , Figure 4 , Figure 5 , Figure 6 As shown, the first-stage planetary gear reduction mechanism 2 includes an axially flat sun gear 25 and an internal gear 24, four axially flat planetary gears 23 arranged between the sun gear 25 and the internal gear 24, and an axially flat planetary disc 22 connected to the planetary gear pin 21. The planetary disc 22 is coaxially connected to the right end of the hollow eccentric input shaft 12 of the second-stage cycloid pinwheel reduction mechanism 1 for transmission. The right end of the hollow eccentric input shaft 12 is axially embedded in the planetary disc 22 for connection and transmission.

[0042] like Figure 7 , Figure 8 As shown, the coaxial connection between the right end of the hollow eccentric input shaft 12 and the planetary disk 22 can be transmitted by spline connection. The coaxial connection between the right end of the hollow eccentric input shaft 12 and the planetary disk 22 can also be transmitted by threaded connection. The coaxial connection between the right end of the hollow eccentric input shaft 12 and the planetary disk 22 can also be transmitted by interference fit connection. As needed, the connection between the right end of the hollow eccentric input shaft 12 and the planetary disk 22 can be connected in a variety of ways. As long as the hollow eccentric input shaft 12 can be axially embedded in the planetary disk 22 for connection and transmission.

[0043] like Figure 2 , Figure 4As shown, each part in the planetary gear reduction mechanism of the present invention adopts an axially flattened structural design, especially the output member is set as an axially flat planetary disc, which has high rigidity and small axial size. The input shaft of the cycloid pinwheel reduction mechanism and the output shaft of the planetary gear reduction mechanism share a common shaft transmission structure, omitting the output shaft of the planetary gear reduction mechanism and reducing the weight of the joint module. At the same time, the planetary disc and the hollow eccentric input shaft are connected and driven by splines, threads or interference fits, and the structure is simple and the axial size is short; that is, the axial size of the entire shutdown module can be reduced by adopting a structural mode in which the cycloid pinwheel reduction mechanism and the planetary gear reduction mechanism are axially embedded. When the sun gear 25 of the first-stage planetary gear reduction mechanism 2 rotates with input torque, the four planetary gears 23 rotate around the sun gear and between the sun gear 25 and the internal gear 24, and the planetary disc 22 connected to the planetary gear 23 through the planetary gear pin 21 also rotates around the axis of the sun gear 25. At the same time, the planetary disc 22 drives the hollow eccentric input shaft 12 connected to one side thereof to rotate, thereby causing the second-stage cycloid pinwheel reduction mechanism 1 to transmit, and the output connecting component 13 on the right side thereof rotates to output power. According to actual needs, the first-stage planetary gear reduction mechanism can also be a multi-stage planetary gear reduction mechanism or a multi-stage NGW mechanism to adapt to various use occasions.

[0044] like Figure 2 As shown, the driving component 3 is a frameless torque motor, and the shaft of the motor shares a common shaft with the hollow shaft 26 of the sun gear 25 of the first-stage planetary gear reduction mechanism 2, that is, the right side of the flat sun gear 25 is connected to the hollow shaft 26 as a whole, and the rotor of the frameless torque motor is arranged on the hollow shaft 26. The hollow shaft 26 is both the motor output shaft of the driving component 3 and the input shaft of the first-stage planetary gear reduction mechanism 2. Then, a rotating shaft is omitted, and the weight is reduced. When the frameless torque motor is powered on, the hollow shaft 26 rotates together with the sun gear 25, thereby driving the first-stage planetary gear reduction mechanism 2 to transmit, and then the planetary disk 22 drives the hollow eccentric input shaft 12 to rotate, so that the second-stage cycloid pinwheel reduction mechanism 1 is transmitted and the output connecting component 13 on its right side rotates to output power. The input shaft of the first-stage planetary gear reduction mechanism of the present invention shares a common shaft with the output shaft of the frameless torque motor. That is, the axial dimension of the entire shutdown module can also be reduced by adopting the structural mode of axially embedding the planetary gear reduction mechanism and the frameless motor. The hollow eccentric input shaft 12 is a large diameter hollow shaft, and the hollow diameter is larger than the diameter of the hollow shaft 26 of the sun gear. In addition to being convenient for wiring, the large diameter hollow structure can also reduce the weight of the joint module, and the size of the hollow can be designed and adjusted as needed. In addition, the first-stage planetary gear reduction mechanism 2 and the drive component 3 omit the outer shell of the original independent components, reducing the radial size and also reducing the weight of the joint module.

[0045] Compared with the existing joint modules, the present invention has a more compact and lightweight structure, strong support rigidity, high assembly coaxiality, low noise, smoother operation, high torque density, long life, and is more competitive. The present invention is used as a miniaturized joint module to meet the requirements of miniaturization, large hollow, high rigidity, and high life.

[0046] It should be noted that the terms used in this specification are only for describing specific embodiments and are not intended to limit the present invention. Unless otherwise specifically stated, the relative arrangement, numerical expressions and numerical values ​​of the technical features and steps described in these embodiments do not limit the scope of protection of the present invention. For the technology, methods and equipment known to ordinary technicians in the relevant field, this specification is not discussed in detail, but in appropriate cases, the technology, methods and equipment should be regarded as part of this specification. Any specific value in this specification should be interpreted as being merely exemplary and not constituting a limitation of the present invention.

[0047] For the convenience of description, the terms describing the position used in the specification, such as "above...", "to the left of...", "in front of...", etc., are only used to describe the spatial position relationship between a certain component and other components of the embodiment shown in the figure. When the position of the component is different, the relative position will change. Therefore, the position relationship of the embodiment of the drawing should not constitute a limitation to the present invention.

[0048] In addition, it should be noted that the words "first", "second" and the like used in the specification are only used to distinguish similar components, and there is no order of precedence, so they cannot be understood as limiting the scope of protection of the present invention. The above description is only a specific implementation of the present invention. It should be pointed out that any modification, equivalent substitution and change made within the spirit and framework of the present invention should be included in the scope of protection of the present invention.

Claims

1. A compact planetary cycloid joint module, comprising a first-stage planetary gear reduction mechanism, a second-stage cycloid pinwheel reduction mechanism and a driving component, characterized in that: The hollow eccentric input shaft of the second-stage cycloid pinwheel reduction mechanism is used for coaxial transmission with the output shaft of the first-stage planetary gear reduction mechanism.

2. The compact planetary cycloid joint module according to claim 1, characterized in that: The first-stage planetary gear reduction mechanism includes an axially flat sun gear and an internal gear, an axially flat planetary gear arranged between the sun gear and the internal gear, and an axially flat planetary disc connected to the pin shaft of the planetary gear. The planetary disc is connected to one end of the hollow eccentric input shaft for coaxial transmission.

3. The compact planetary cycloid joint module according to claim 2, characterized in that: The planetary disc is connected to one end of the hollow eccentric input shaft for transmission via a spline.

4. The compact planetary cycloid joint module according to claim 2, characterized in that: The planetary disc is connected to one end of the hollow eccentric input shaft for transmission via threads.

5. The compact planetary cycloid joint module according to claim 2, characterized in that: The planetary disc is connected and driven with one end of the hollow eccentric input shaft through interference fit.

6. The compact planetary cycloid joint module according to claim 2, characterized in that: The rotating shaft of the sun gear is a hollow shaft, which is coaxially driven with the output shaft of the driving component.

7. The compact planetary cycloid joint module according to claim 1, characterized in that: The second-stage cycloid pinwheel reduction mechanism comprises a pin-cycloid meshing mechanism arranged on the hollow eccentric input shaft, a plate-shaped output connecting component arranged on both sides of the pin-cycloid meshing mechanism, and a fixed connecting component arranged on the outer circle of the output connecting component.

8. The compact planetary cycloid joint module according to claim 1, characterized in that: The driving component is a frameless torque motor, the shaft of which is coaxial with the hollow shaft of the sun gear of the first-stage planetary gear reduction mechanism, and the rotor of the frameless torque motor is arranged on the hollow shaft.

9. The compact planetary cycloid joint module according to claim 2, characterized in that: The hollow eccentric input shaft is a large-diameter hollow shaft, wherein the hollow diameter thereof is larger than the diameter of the hollow shaft of the sun gear.

10. The compact planetary cycloid joint module according to claim 1, characterized in that: The first-stage planetary gear reduction mechanism is a multi-stage planetary gear reduction mechanism or a multi-stage NGW mechanism.

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