CN111216117B - Nested robot integrated joint with two-stage planetary reduction structure - Google Patents

Abstract

The invention discloses a robot integrated joint with a nested two-stage planetary reduction structure, which comprises the following components: the robot comprises a motor, a speed reducer and a joint shell, wherein the joint shell is connected with a robot body or a primary limb connecting rod of the robot, and the motor and the speed reducer are arranged at two ends of the joint shell along the axial direction; the speed reducer is connected with an output shaft of the motor; the robot comprises a primary planetary transmission wheel assembly and a secondary planetary transmission wheel assembly, wherein the primary planetary transmission wheel assembly is connected with an output shaft of a motor, and the secondary planetary transmission wheel assembly is fixedly connected with a next-stage limb connecting rod of the robot; the primary planetary transmission wheel assembly and the secondary planetary transmission wheel assembly are of an inner-outer nested structure and are in transmission connection through a collar. The invention discloses a robot integrated joint with a nested two-stage planetary reduction structure, which is formed by integrally designing a motor, a reducer and a joint shell, and has the advantages of compact structure, small inertia and power generation and certain speed change capability.

Description

A robot integrated joint with a nested two-stage planetary reduction structure

Technical Field

The present invention relates to the field of robot technology, and more particularly to a robot integrated joint with a nested two-stage planetary reduction structure.

Background Art

Robot joints are used to connect robot link component units on the one hand, and provide power for the robot on the other hand. Robot joints are generally composed of drive motors, reducers, sensors and auxiliary components, joint housings and mechanical interfaces. Compared with other components in the robot system, robot joints have higher requirements for overall design, including reducing weight, reducing volume, achieving appropriate transmission ratios, and improving responsiveness.

However, at present, the design scheme commonly adopted by existing robot joint devices is to directly connect and functionally combine common components such as motors and reducers, lacking substantial integrated design, making it difficult to combine the overall mass size limit of the joint with high torque density, and the reduction ratio configuration is not flexible enough, which is also one of the key factors restricting the development of high dynamic performance bionic robots and industrial robot technology.

Therefore, how to provide a robot integrated joint with a compact nested two-stage planetary reduction structure is an urgent problem to be solved by those skilled in the art.

Summary of the invention

In view of this, the present invention provides a robot integrated joint with a nested two-stage planetary reduction structure, which integrates the motor, reducer and joint housing into an integrated design, and has the advantages of compact structure, small inertia, power generation and certain speed change capabilities.

In order to achieve the above-mentioned purpose, the present invention adopts the following technical scheme: a robot integrated joint with a nested two-stage planetary reduction structure, comprising: a motor, a reducer and a joint housing, the joint housing being connected to the robot body or the robot's upper limb connecting rod as the input end of the robot integrated joint, the motor and the reducer being arranged at both ends of the joint housing along the axial direction, and both being fixedly connected to the joint housing; the reducer being connected to the output shaft of the motor; the reducer being fixedly connected to the robot's lower limb connecting rod; the motor being the power source of the robot integrated joint, and the rotational power generated by the motor being changed in speed by the reducer as the power output of the robot joint.

Among them, the reducer is an inside-outside nested structure, including: a first-level planetary transmission wheel assembly and a second-level planetary transmission wheel assembly, the first-level planetary transmission wheel assembly is connected to the output shaft of the motor, and the second-level planetary transmission wheel assembly is fixedly connected to the next-level limb connecting rod of the robot; and the positional relationship between the first-level planetary transmission wheel assembly and the second-level planetary transmission wheel assembly is set as a parallel inside-outside nested structure and is connected through a shaft ring transmission.

Preferably, the first-stage planetary transmission wheel assembly includes: a first-stage sun gear, a first-stage planetary gear, a first-stage planet carrier and an inner ring gear, the first-stage sun gear is fixedly connected to the rotor of the motor; the first-stage sun gear is meshed with the first-stage planetary gear, the first-stage planetary gear is connected to the first-stage planet carrier through a pin shaft, the inner ring gear serves as the ring gear structure of the first-stage planetary transmission wheel assembly, the first-stage planetary gear is meshed with the inner ring gear; the first-stage planet carrier is fixedly connected to the joint housing; and the rotation axes of the first-stage sun gear and the inner ring gear are in a collinear relationship.

The secondary planetary transmission wheel assembly includes: an outer ring gear, a secondary planetary gear, a secondary planetary carrier and a secondary ring gear, the outer ring gear is fixed to the outer surface of the shaft ring, the inner surface of the shaft ring is fixedly connected to the inner ring gear, and the rotation axes of the outer ring gear, the inner ring gear and the shaft ring are in a collinear relationship; the outer ring gear serves as the sun gear structure of the secondary planetary transmission wheel assembly, meshing with the secondary planetary gear, the secondary planetary gear is connected to the secondary planetary carrier through a pin shaft, and the secondary planetary gear is meshed with the secondary ring gear; the secondary ring gear is fixedly connected to the joint housing; the secondary planetary carrier is fixedly connected to the next-level limb connecting rod of the robot, serving as the output connection end of the robot joint; the rotation axes of the outer ring gear, the secondary planetary gear and the secondary planetary carrier are in a collinear relationship.

Preferably, the inner gear ring, the shaft ring and the outer gear ring constitute a double-sided gear, the double-sided gear is a torus structure, the first-stage planetary transmission wheel assembly is located in a cylindrical cavity inside the torus structure, the second-stage planetary transmission wheel assembly is located outside the torus structure, and the first-stage planetary transmission wheel assembly and the second-stage planetary transmission wheel assembly form a parallel inside-outside nested structure in terms of positional relationship; the first-stage planetary transmission wheel assembly transmits power to the second-stage planetary transmission wheel assembly through the double-sided gear.

The rotational power input by the motor is transmitted through the power of the primary sun gear, the primary planetary gear, the inner gear ring of the double-sided gear, the outer gear ring of the double-sided gear, the secondary planetary gear, and the secondary planetary carrier, and is output by the secondary planetary carrier to the next-level limb connecting rod. Among them, the rotation axes of the primary sun gear, the double-sided gear, and the secondary planetary carrier are in a collinear relationship. The shape and position relationship between the primary planetary transmission wheel assembly and the secondary planetary transmission wheel assembly is a nested structure, and the secondary planetary transmission wheel assembly is nested outside the primary planetary transmission wheel assembly; the transmission relationship is a series structure, and the power output of the motor is transmitted to the secondary planetary transmission wheel assembly through the primary planetary transmission wheel assembly, and is output by the secondary planetary transmission wheel assembly.

Preferably, the inner gear ring and the outer gear ring are connected to the shaft ring via splines.

Preferably, the inner gear ring and the outer gear ring are connected to the shaft ring through adhesives.

The first-stage planetary transmission wheel assembly adopts a circular working mode. The rotational power is transmitted to the inner ring gear through the first-stage sun gear and the first-stage planetary gear, thereby driving the double-sided gear to rotate around the motion axis of the first-stage sun gear; during the working process, the first-stage planet carrier is fixed and the inner ring gear outputs rotational power, that is, the first-stage planetary transmission wheel assembly adopts a circular working mode.

The secondary planetary transmission wheel assembly adopts a frame-driven working mode. The rotational power of the double-sided gear is transmitted to the secondary planetary carrier through the outer ring gear and the secondary planetary gear, thereby driving the secondary planetary carrier to rotate around the motion axis of the primary sun gear, thereby realizing the power output of the robot joint; during the working process, the secondary ring gear is fixed and the secondary planetary carrier outputs rotational power, that is, the secondary planetary transmission wheel assembly adopts a frame-driven working mode.

The special positional relationship design of the primary planetary transmission wheel assembly and the secondary planetary transmission wheel assembly enables the robot joint to achieve a larger reduction ratio and higher torque density in a compact space compared to traditional planetary reducers. Under a specific number of teeth configuration, the reducer can provide a reduction ratio of 10 to 12 and high torque density within an axial dimension of 40 mm.

It can be seen from the above technical solutions that, compared with the prior art, the present invention discloses a robot integrated joint with a nested two-stage planetary reduction structure, which achieves the following technical effects:

(1) The robot joint adopts an integrated design. The functions and structures of the motor, reducer, and joint housing are designed as one piece. It has a compact structure, light weight, and can achieve high torque density.

(2) The reducer adopts an inner-outer nested structure. The first-stage planetary transmission wheel assembly and the second-stage planetary transmission wheel assembly are in parallel in terms of shape and position, and in series in terms of transmission. It can provide a reduction ratio of 10 to 12 within an axial dimension of 40 mm, realizing the flattened design of the robot joint in the axial direction, and is easy to use in compact bionic robot limbs.

(3) The double-sided gear effectively connects the primary planetary transmission wheel assembly and the secondary planetary transmission wheel assembly, and realizes a compact internal and external nested structure, effectively reducing the joint size.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

FIG. 1 is a schematic diagram of the structure provided by the present invention.

FIG. 2 is a schematic diagram of the overall assembly solution provided by the present invention.

FIG3 is a schematic diagram of the structure of the double-sided gear provided by the present invention.

FIG. 4 is a schematic diagram of a double-sided gear provided by the present invention.

FIG5 is a schematic diagram of an application scenario provided by the present invention.

Among them, the figures are as follows:

Motor, 2-reducer, 3-joint housing, 21-first-stage sun gear, 22-first-stage planetary gear, 23-first-stage planetary carrier, 24-double-sided gear, 25-second-stage planetary gear, 26-second-stage planetary carrier, 27-secondary ring gear, 241-outer ring gear, 242-inner ring gear, 243-shaft collar, 41-upper-stage limb connecting rod, 42-lower-stage limb connecting rod, 11-motor stator, 12-motor rotor.

DETAILED DESCRIPTION

The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

As shown in Figure 1, the embodiment of the present invention discloses a robot integrated joint with a nested two-stage planetary reduction structure, including a motor 1, a reducer 2, and a joint housing 3. The joint housing 3 is connected to the robot body or the upper limb link 41 of the robot as the input connection end of the robot joint. The motor 1 and the reducer 2 are respectively arranged at the two ends of the axial direction of the joint housing 3, and are respectively fixedly connected to the joint housing 3. The motor 1 is the power source of the robot joint. The rotational power generated by the motor 1 is used as the power output of the robot joint after the speed is changed by the reducer 2. The motor 1 and the reducer 2 are arranged in series to jointly constitute the internal transmission wheel assembly of the robot joint.

Fig. 2 is a schematic diagram of the overall assembly scheme of a robot integrated joint of a nested two-stage planetary reduction structure of the present invention. As shown in Fig. 2, the motor 1 includes a stator 11 and a rotor 12, wherein the stator 11 is fixedly connected to the joint housing 3, and the rotor 12 is connected to the stator 11 through a bearing, and the rotor 12 and the stator 11 can rotate relative to each other.

The reducer 2 includes a primary sun gear 21, a primary planetary gear 22, a primary planetary carrier 23, a double-sided gear 24, a secondary planetary gear 25, a secondary planetary carrier 26, and a secondary ring gear 27. The primary sun gear 21 is fixedly connected to the rotor 12. The primary planetary carrier 23 is fixedly connected to the joint housing 3, and the secondary ring gear 27 is fixedly connected to the joint housing 3. The secondary planetary carrier 26 is fixedly connected to the next-level limb link 42 of the robot, serving as the output connection end of the robot joint.

The double-sided gear 24 is a toroidal structure, including an inner gear ring 242, an outer gear ring 241 and a collar 243. The collar 243 is a toroidal structure, the inner surface of the toroidal structure of the collar 243 is fixedly connected to the inner gear ring 242, the outer surface of the toroidal structure of the collar 243 is fixedly connected to the outer gear ring 241, and the rotation axes of the collar 243, the inner gear ring 242 and the outer gear ring 241 are in a colinear relationship.

The inner gear ring 242, the primary sun gear 21, the primary planetary gear 22, and the primary planet carrier 23 together constitute a primary planetary transmission wheel assembly; the primary sun gear 21 is meshed with the primary planetary gear 22, the primary planetary gear 22 is connected to the primary planet carrier 23 through a pin shaft, and the primary planetary gear 22 is meshed with the inner gear ring 242; the outer gear ring 241 of the double-sided gear 24, the secondary planetary gear 25, the secondary planetary carrier 26, and the secondary gear ring 27 together constitute a secondary planetary transmission wheel assembly; the outer gear ring 241 acts as a secondary sun gear, which is meshed with the secondary planetary gear 25, the secondary planetary gear 25 is connected to the secondary planet carrier 26 through a pin shaft, and the secondary planetary gear 25 is meshed with the secondary gear ring 27; the rotational power input by the motor 1 is transmitted in sequence through the primary sun gear 21, the primary planetary gear 22, the inner gear ring 242, the outer gear ring 241, the secondary planetary gear 25, and the secondary planet carrier 26, and then output to the next-level limb connecting rod 42 of the robot.

Among them, the rotation axes of the primary sun gear 21 and the inner gear ring 242 are in a collinear relationship; the rotation axes of the outer gear ring 241, the secondary planetary gear 25, and the secondary planetary carrier 26 are in a collinear relationship.

The inner gear ring 242 serves as the gear ring structure of the primary planetary transmission gear assembly and meshes with the primary planetary gear 22 . The outer gear ring 241 serves as the sun gear structure of the secondary planetary transmission gear assembly and meshes with the secondary planetary gear 25 .

Specifically, the reducer 2 includes a primary planetary transmission wheel assembly and a secondary planetary transmission wheel assembly. The primary planetary transmission wheel assembly is located in the cylindrical cavity inside the torus structure of the double-sided gear 24, and the secondary planetary transmission wheel assembly is located outside the torus structure of the double-sided gear 24. The shape and position relationship between the primary planetary transmission wheel assembly and the secondary planetary transmission wheel assembly is an inside-outside nested structure, and the secondary planetary transmission wheel assembly is nested outside the primary planetary transmission wheel assembly; the transmission relationship is a series structure, and the power output by the motor 1 is transmitted to the secondary planetary transmission wheel assembly through the primary planetary transmission wheel assembly, and is output by the secondary planetary transmission wheel assembly.

The first-stage planetary transmission wheel assembly adopts a circular working mode. The rotational power output by the motor 1 is transmitted to the inner ring 242 through the first-stage sun gear 21 and the first-stage planetary gear 22, thereby driving the double-sided gear 24 to rotate around the motion axis of the first-stage sun gear 21; during the working process, the first-stage planetary carrier 23 is fixed and the inner ring 242 outputs rotational power, that is, the first-stage planetary transmission wheel assembly adopts a circular working mode.

The secondary planetary transmission wheel assembly adopts a frame-moving working mode. The rotational power of the double-sided gear 24 is transmitted to the secondary planetary carrier 26 through the outer ring gear 241 and the secondary planetary wheel 25, thereby driving the secondary planetary carrier 26 to rotate around the motion axis of the primary sun gear 21, thereby realizing the power output of the robot joint; during the working process, the secondary ring gear 27 is fixed and the secondary planetary carrier 26 outputs rotational power, that is, the secondary planetary transmission wheel assembly adopts a frame-moving working mode.

Compared with the traditional planetary gear train structure, the single disk of the present invention includes a first-stage planetary transmission wheel assembly and a second-stage planetary transmission wheel assembly in a nested relationship, and the transmission relationship of the two-stage transmission wheel assembly is in series, so that the space originally used for the single-stage planetary gear train is more fully utilized, so that the reducer has a relatively high reduction ratio. Under a specific number of teeth configuration, the reducer 2 can provide a reduction ratio of 10 to 12 within an axial dimension of 40 mm, thereby achieving a high torque density.

Figures 3 and 4 show the schematic diagram and simplified diagram of the double-sided gear structure. The double-sided gear 24 is a solid combination of an inner gear ring 242, an outer gear ring 241, and a shaft ring 243. The basic processing method is one of the following methods:

Directly process the inner gear ring 242, the outer gear ring 241, and the shaft ring 243 on the blank of the double-sided gear 24; process the inner gear ring 242, the outer gear ring 241, and the shaft ring 243 as individual parts separately, and connect the inner gear ring 242, the shaft ring 243, and the outer gear ring 241 together through splines;

Alternatively, the inner gear ring 242 , the outer gear ring 241 , and the shaft collar 243 are processed separately, and the inner gear ring 242 , the shaft collar 243 and the outer gear ring 241 are connected together by adhesive.

FIG5 is a schematic diagram of an application embodiment of a robot integrated joint of a nested two-stage planetary reduction structure of the present invention. The upper-level limb link 41 of the robot is fixedly connected to the joint housing 3, and the lower-level limb link 42 of the robot is fixedly connected to the secondary planetary frame 26. The rotational power output by the motor 1 is output to the lower-level limb link 42 of the robot after speed change by the reducer 2, thereby driving the lower-level limb link 42 of the robot to move.

It can be seen from this example that the robot integrated joint provided by the present invention has a compact structure and a simple connection scheme, and can be used for a robot high-performance bionic arm and bionic leg structure system.

In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims (4)

1. A robot integrated joint with a nested two-stage planetary reduction structure, comprising: a motor (1), a reducer (2) and a joint housing (3), wherein the joint housing (3) is fixedly connected to a robot body or a robot upper limb connecting rod (41); the reducer (2) is fixedly connected to a robot lower limb connecting rod (42); the motor (1) and the reducer (2) are arranged at two ends of the joint housing (3) along the axial direction, and are both fixedly connected to the joint housing (3); the reducer (2) is connected to an output shaft of the motor (1); characterized in that it comprises: a primary planetary transmission wheel assembly and a secondary planetary transmission wheel assembly, wherein the primary planetary transmission wheel assembly is connected to the output shaft of the motor (1), and the secondary planetary transmission wheel assembly is fixedly connected to the robot lower limb connecting rod (42); the primary planetary transmission wheel assembly and the secondary planetary transmission wheel assembly are of an inner and outer nested structure and are transmission-connected via a shaft ring (243); The first-stage planetary transmission wheel assembly comprises: a first-stage sun wheel (21), a first-stage planet wheel (22), a first-stage planet carrier (23) and an inner gear ring (242); the first-stage sun wheel (21) and the rotor (12) of the motor (1) are fixedly connected; the first-stage sun wheel (21) is meshed with the first-stage planet wheel (22); the first-stage planet wheel (22) is connected to the first-stage planet carrier (23) via a pin shaft; the first-stage planet wheel (22) is meshed with the inner gear ring (242); the first-stage planet carrier (23) is fixedly connected to the joint housing (3); and the rotation axes of the first-stage sun wheel (21) and the inner gear ring (242) are in a collinear relationship; The secondary planetary transmission wheel assembly comprises: an outer ring gear (241), a secondary planetary wheel (25), a secondary planet carrier (26) and a secondary ring gear (27); the outer ring gear (241) is fixed to the outside of the shaft ring (243), and the inside of the shaft ring (243) is fixedly connected to the inner ring gear (242); Furthermore, the rotation axes of the outer gear ring (241), the inner gear ring (242), and the shaft ring (243) are in a colinear relationship; The outer gear ring (241) meshes with the secondary planetary gear (25); the secondary planetary gear (25) is connected to the secondary planetary carrier (26) via a pin shaft; the secondary planetary gear (25) meshes with the secondary gear ring (27); the secondary gear ring (27) is fixedly connected to the joint housing (3); the secondary planetary carrier (26) is fixedly connected to the next-level limb connecting rod (42) of the robot, serving as an output connection end of the robot joint; The rotation axes of the outer gear ring (241), the secondary planetary gear (25), and the secondary planetary carrier (26) are in a collinear relationship; The inner gear ring (242), the shaft ring (243) and the outer gear ring (241) constitute a double-sided gear (24); the double-sided gear (24) is a torus structure; the first-stage planetary transmission wheel assembly is located in a cylindrical cavity inside the torus structure; the second-stage planetary transmission wheel assembly is located outside the torus structure; the first-stage planetary transmission wheel assembly and the second-stage planetary transmission wheel assembly form an inner-outer nested structure in terms of positional relationship. 2. A robot integrated joint with a nested two-stage planetary reduction structure according to claim 1, characterized in that the inner gear ring (242) and the outer gear ring (241) are connected to the shaft ring (243) through splines. 3. The robot integrated joint with a nested two-stage planetary reduction structure according to claim 1, characterized in that the inner gear ring (242) and the outer gear ring (241) are connected to the shaft ring (243) by adhesive. 4. According to the robot integrated joint of the nested two-stage planetary reduction structure described in claim 1, the first-stage planetary transmission wheel assembly is a circular motion working mode, and the rotational power is transmitted to the inner ring (242) through the first-stage sun gear (21) and the first-stage planetary gear (22), thereby driving the double-sided gear (24) to rotate around the movement axis of the first-stage sun gear (21); during the working process, the first-stage planet carrier (23) is fixed and the inner ring (242) outputs the rotational power, that is, the first-stage planetary transmission wheel assembly adopts a circular motion working mode; The secondary planetary transmission wheel assembly adopts a frame-driven working mode, and the rotational power of the double-sided gear (24) is transmitted to the secondary planetary carrier (26) through the outer ring gear (241) and the secondary planetary gear (25), thereby driving the secondary planetary carrier (26) to rotate around the movement axis of the primary sun gear (21), thereby realizing the power output of the robot joint; during the working process, the secondary ring gear (27) is fixed and the secondary planetary carrier (26) outputs the rotational power, that is, the secondary planetary transmission wheel assembly adopts a frame-driven working mode.