A planetary joint module and robot

Abstract

The present invention provides a planetary joint module and a robot, comprising a housing, a drive plate, a motor and a planetary gear train, wherein the drive plate is located at the input side of the housing, the motor is located inside the housing, and the planetary gear train is located at the output side of the housing; the drive plate is connected to the motor signal, and the motor is connected to the planetary gear train by transmission; a first encoder, the first encoder is located at the input end of the housing, and the first encoder is connected to the motor; a second encoder, the second encoder is located at the input end of the housing, and a transmission shaft is connected to the planetary gear train, and the second encoder is connected to the transmission shaft. The present invention uses a second encoder for detecting the rotation speed of the output end planetary gear train through the transmission shaft, which can be set at the input end, and occupies a common axial dimension with the first encoder for detecting the rotation speed of the input end, effectively shortening the axial dimension of the module, and making the volume more compact; the first encoder and the second encoder are used to realize dual real-time detection of the motor rotation speed and the output end rotation speed of the planetary gear train, thereby improving the control accuracy of the joint module.

Description

Technical Field

[0001] The present invention relates to the field of robot technology, and in particular to a planetary joint module and a robot. Background Art

[0002] The planetary joint module integrates the motor, planetary reducer, encoder, and drive board into one. The joint module structure is highly integrated, compact in size, and has high power density, and can be used on humanoid robots.

[0003] Currently, most arm joint modules on the market are harmonic modules, which are high in cost, weight and size. Planetary modules are mostly used in the leg joints of humanoid robots, and have a first-stage planetary reduction gear, a large diameter and a low speed ratio, and cannot be used on hand joints.

[0004] The speed control of the joint module needs to be combined with an encoder for speed measurement, but the speed measurement point in the prior art is usually single-ended, that is, it can only measure the speed of the input end or the output end, resulting in low module control accuracy. In addition, for some joint modules that measure the speed of both the input and output ends, since the speed measurement points are set at the input and output ends of the module respectively, the axial size of the joint module is also increased. Summary of the invention

[0005] The object of the present invention is to provide a planetary joint module and a robot, which can shorten the axial dimension of the module and make the volume more compact;

[0006] The present invention provides a planetary joint module, comprising a shell, and also comprising a drive plate, a motor and a planetary gear train, wherein the drive plate is located at the input side of the shell, the motor is located inside the shell, and the planetary gear train is located at the output side of the shell; the drive plate is connected to the motor signal, and the motor is connected to the planetary gear train in transmission; a first encoder, the first encoder is located at the input end of the shell, and the first encoder is connected to the motor; a second encoder, the second encoder is located at the input end of the shell, a transmission shaft is connected to the planetary gear train, and the second encoder is connected to the transmission shaft.

[0007] Furthermore, the planetary gear train includes a primary planetary gear train and a secondary planetary gear train, the primary planetary gear train is connected to the motor, and the secondary planetary gear train is connected to the primary planetary gear train.

[0008] Furthermore, hollow structures are respectively provided in the sun gears of the primary planetary gear train and the secondary planetary gear train, and the transmission shaft passes through the hollow structures to be connected to the output-end planet carrier.

[0009] Furthermore, an input magnetic ring connecting plate and an output magnetic ring connecting plate are provided at the input end of the shell, the input magnetic ring connecting plate is connected to the motor, the output magnetic ring connecting plate is connected to the transmission shaft, the magnetic ring of the first encoder is arranged on the input magnetic ring connecting plate, and the magnetic ring of the second encoder is arranged on the output magnetic ring connecting plate; the output magnetic ring connecting plate is located radially inside the input magnetic ring connecting plate, and the magnetic ring of the first encoder and the magnetic ring of the second encoder are located in the same plane.

[0010] Furthermore, the driving board is provided with a sensing chip of the first encoder and a sensing chip of the second encoder.

[0011] Furthermore, a control module is provided on the driving board, and a signal connection is formed between the control module and the motor, the sensing chip of the first encoder and the sensing chip of the second encoder.

[0012] Furthermore, the motor is a frameless torque motor, and the primary planetary gear train is built inside the motor.

[0013] Furthermore, the first-stage planetary gear train and the second-stage planetary gear train respectively include a ring gear, and the ring gear includes an inner ring and an outer ring, and the outer ring is made of a lighter material than the inner ring.

[0014] Furthermore, the inner ring is made of alloy steel, and the outer ring is made of aluminum alloy.

[0015] The invention provides a robot which adopts a planetary joint module.

[0016] The technical solution of the present invention connects a transmission shaft to the planetary gear train, thereby transmitting the rotation speed of the planetary gear train at the output end to the input end, so that the second encoder for detecting the output end rotation speed can be set at the input end, and occupies the same axial dimension as the first encoder for detecting the input end rotation speed, thereby effectively shortening the axial dimension of the module and making the volume more compact; the present invention also realizes dual real-time detection of the motor speed and the output end rotation speed of the planetary gear train through the first encoder and the second encoder, which can effectively improve the control accuracy of the joint module. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 is an internal cross-sectional view of the present invention;

[0019] Figure 2 A schematic diagram of the arrangement of the first encoder and the second encoder of the present invention;

[0020] Figure 3 It is a schematic diagram of the arrangement of the primary planetary gear train and the secondary planetary gear train of the present invention;

[0021] Figure 4 Schematic diagram of the ring gears of the primary planetary gear train and the secondary planetary gear train of the present invention;

[0022] Description of reference numerals:

[0023] 1-housing; 2-motor; 3-planetary gear train; 301-primary planetary gear train; 302-secondary planetary gear train; 303-hollow structure; 304-output end planetary carrier; 305-transmission shaft; 4-input magnetic ring connecting plate; 401-magnetic ring of the first encoder; 5-output magnetic ring connecting plate; 501-magnetic ring of the second encoder; 6-driving plate; 601-sensing chip of the first encoder; 602-sensing chip of the second encoder; 7-gear ring; 701-inner ring; 702-outer ring; 8-cross roller bearing. DETAILED DESCRIPTION

[0024] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, rather than 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.

[0025] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0026] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, "multiple" means two or more, unless otherwise clearly and specifically defined. In addition, the terms "installed", "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0027] Example 1

[0028] like Figure 1-Figure 4 As shown, the present invention provides a planetary joint module, including a shell 1, and also including a drive plate 6, a motor 2 and a planetary gear train 3, the drive plate 6 is located at the input side of the shell 1, the motor 2 is located in the shell 1, the planetary gear train 3 is located at the output side of the shell 1, the drive plate 6 is signal-connected with the motor 2, and the motor 2 is transmission-connected with the planetary gear train 3; a first encoder, the first encoder is located at the input end of the shell 1, and the first encoder is connected to the motor 2; a second encoder, the second encoder is located at the input end of the shell 1, a transmission shaft 305 is connected to the planetary gear train 3, and the second encoder is connected to the transmission shaft 305.

[0029] Specifically, in this embodiment, the driving board 6 is a PCB circuit board with an integrated encoder sensor chip, which is located at the input end signal connection and controls the rotation of the motor 2. The motor 2 is located at the input end of the housing 1 as a power source, and is output at the output end after being decelerated by the planetary gear train 3. The planetary gear train 3 includes a planetary gear reducer, including a ring gear 7, a sun gear and a planetary gear structure, which is a prior art structure and its structural principle is not repeated.

[0030] The control of the joint module requires real-time detection of the rotation speed of the motor 2 and the output end planetary carrier 304 by the encoder. Since the motor 2 and the output end planetary carrier 304 are located on both sides of the input end and the output end respectively, in the prior art, an encoder is generally set at the input end to detect the rotation speed of the motor 2, and an encoder is set at the output end to detect the rotation speed of the planetary carrier, so two sections of axial spacing will be occupied. In the present invention, a slender shaft is connected to the planetary gear train 3 as a transmission shaft 305, one end of the transmission shaft 305 is connected to the output end planetary carrier 304 of the planetary gear train 3, and the other end passes through the planetary gear train 3 and the motor 2 to extend to the input end, so that the transmission shaft 305 transmits the rotation speed of the output end planetary carrier 304 of the planetary gear train 3 to the input end, so that the second encoder for detecting the output end rotation speed can also be set at the input end, and occupies the same axial dimension (different radial position) with the first encoder for detecting the input end rotation speed, thereby effectively shortening the axial dimension of the module and making the volume more compact.

[0031] The present invention also connects the first encoder and the second encoder through the signal of the driving board 6 to realize dual real-time detection of the rotation speed of the input end motor 2 and the rotation speed of the output end planet carrier 304 of the planetary gear train 3, which can effectively improve the control accuracy of the joint module.

[0032] Example 2

[0033] The planetary gear train 3 includes a primary planetary gear train 301 and a secondary planetary gear train 302 . The primary planetary gear train 301 is connected to the motor 2 , and the secondary planetary gear train 302 is connected to the primary planetary gear train 301 .

[0034] Specifically, in this embodiment, the planetary gear train 3 adopts a two-stage planetary gear transmission. The speed of the motor 2 is decelerated by the first-stage planetary gear train 301 and then decelerated by the second-stage planetary gear train 302. The total reduction ratio can reach 30-50, and the maximum speed ratio can reach 100.

[0035] Example 3

[0036] A hollow structure 303 is provided in the sun gear of the primary planetary gear train 301 and the secondary planetary gear train 302, respectively, and the transmission shaft 305 passes through the hollow structure 303 and is connected to the output end planet carrier 304. An input magnetic ring connecting plate 4 and an output magnetic ring connecting plate 5 are provided at the input end of the housing 1, the input magnetic ring connecting plate 4 is connected to the motor 2, and the output magnetic ring connecting plate 5 is connected to the transmission shaft 305. The magnetic ring 401 of the first encoder is arranged on the input magnetic ring connecting plate 4, and the magnetic ring 501 of the second encoder is arranged on the output magnetic ring connecting plate 5; the output magnetic ring connecting plate 5 is located radially inside the input magnetic ring connecting plate 4, and the magnetic ring 401 of the first encoder and the magnetic ring 501 of the second encoder are located in the same plane. The driving board 6 is provided with a sensing chip 601 of the first encoder and a sensing chip 602 of the second encoder. The driving board 6 is provided with a control module, and the control module is signal-connected with the motor 2, the sensing chip 601 of the first encoder, and the sensing chip 602 of the second encoder.

[0037] Specifically, in the present embodiment, one end of the transmission shaft 305 is connected to the output end planet carrier 304 of the secondary planetary gear train 302 and rotates therewith, and the transmission shaft 305 body passes through the hollow structure 303 in the sun gear of the primary planetary gear train 301 and the secondary planetary gear train 302, extends to the input end of the module and is connected to the output magnetic ring connecting plate 5, so that the output end planet carrier 304 drives the output magnetic ring connecting plate 5 located at the input end to rotate through the transmission shaft 305.

[0038] The input magnetic ring connecting plate 4 and the output magnetic ring connecting plate 5 are both annular structures and rotate independently; the output magnetic ring connecting plate 5 is located radially inside the input magnetic ring connecting plate 4. The input magnetic ring connecting plate 4 is driven to rotate by the motor 2, and the output magnetic ring connecting plate 5 is driven to rotate by the output end planetary frame 304. The two have different rotation speeds, and thus the magnetic ring 401 of the first encoder and the magnetic ring 501 of the second encoder have different rotation speeds, but the axial dimensions they occupy are the same. This shortens the axial dimension of the module and makes the volume more compact.

[0039] Furthermore, the driving board 6 is arranged outside the input magnetic ring connecting board 4 and the output magnetic ring connecting board 5 (the input magnetic ring connecting board 4 and the output magnetic ring connecting board 5 are located between the driving board 6 and the motor 2), and the sensing chip 601 of the first encoder and the sensing chip 602 of the second encoder are arranged on the driving board 6, and are respectively located at different radial positions. That is, the axial dimension required by the sensing chip 602 of the second encoder is also integrated into the axial dimension required by the sensing chip 601 of the (original) first encoder, thereby further shortening the axial dimension of the module and making the volume more compact.

[0040] The drive board 6 can also be provided with a control circuit and a control chip, etc., to receive the rotation speed of the first encoder and the second encoder through an electrical signal connection, etc., and then output a control strategy through the real-time rotation speed of the two points, and send it to the control system of the motor 2 through an electrical signal connection, etc., to improve the control accuracy of the joint module through the dual encoder configuration. The encoder and the drive board 6 are integrated into a PCB board, which has a compact structure and shortens the axial size of the module.

[0041] Example 4

[0042] The motor 2 is a frameless torque motor, and the primary planetary gear train 301 is built inside the motor 2 .

[0043] Specifically, the motor 2 adopts a frameless torque motor, and the first-stage planetary gear train 301 is built inside the motor, which can further shorten the axial size of the module; and the output end is supported by a single cross roller bearing 8 to reduce the axial gear (conventionally double bearing support), which can further shorten the axial size of the module.

[0044] Example 5

[0045] The primary planetary gear train 301 and the secondary planetary gear train 302 respectively include a gear ring 7, and the gear ring 7 includes an inner ring 701 and an outer ring 702, and the outer ring 702 is made of a lighter material than the inner ring 701. The inner ring 701 is made of alloy steel, and the outer ring 702 is made of aluminum alloy.

[0046] Specifically, in this embodiment, the gear ring 7 is made into a split gear ring 7, the teeth of the inner ring 701 are made of alloy steel to meet the strength and life requirements; the outer ring 702 is made of aluminum alloy to reduce the weight of the gear ring 7; the entire module structure is made of aluminum alloy or engineering plastic materials as much as possible to reduce the weight of the joint module while meeting the strength requirements.

[0047] Example 6

[0048] The present invention provides a robot, which adopts the planetary joint module in Embodiment 1 to Embodiment 5. The other parts of the robot can adopt the existing technical structure, which will not be described in detail.

[0049] Working principle of the present invention:

[0050] One end of the transmission shaft 305 is connected to the output end planet carrier 304 of the secondary planetary gear train 302 and rotates therewith, and the transmission shaft 305 body passes through the hollow structure 303 in the sun gear of the primary planetary gear train 301 and the secondary planetary gear train 302, extends to the input end of the module and is connected to the output magnetic ring connecting plate 5, so that the output end planet carrier 304 drives the output magnetic ring connecting plate 5 located at the input end to rotate through the transmission shaft 305, so that the dual encoder magnetic ring adopts a nested arrangement form, and the second encoder for detecting the output end speed can be set at the input end, and occupies the same axial dimension with the first encoder for detecting the input end speed, and the magnetic ring is in the same plane, thereby effectively shortening the axial dimension of the module and making it more compact. This joint module integrates a frameless motor, a two-stage planetary reducer, a dual encoder, a motor 2, and a cross roller bearing 8; the entire joint module has a compact structure, a small size, a high power density, and a light weight, which meets the use requirements of the humanoid robot for the joint module.

[0051] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A planetary joint module, comprising a housing, characterized in that: It also includes a drive plate, a motor and a planetary gear train, wherein the drive plate is located at the input side of the housing, the motor is located inside the housing, and the planetary gear train is located at the output side of the housing; the drive plate is connected to the motor signal, and the motor is connected to the planetary gear train in a transmission manner; A first encoder, the first encoder is located at an input end of the housing, and the first encoder is connected to the motor; The second encoder is located at the input end of the housing, a transmission shaft is connected to the planetary gear train, and the second encoder is connected to the transmission shaft.

2. The planetary joint module according to claim 1, characterized in that: The planetary gear train includes a primary planetary gear train and a secondary planetary gear train, the primary planetary gear train is connected to the motor, and the secondary planetary gear train is connected to the primary planetary gear train.

3. The planetary joint module according to claim 2, characterized in that: A hollow structure is respectively provided in the sun gear of the primary planetary gear train and the secondary planetary gear train, and the transmission shaft passes through the hollow structure and is connected to the output-end planet carrier.

4. The planetary joint module according to claim 3, characterized in that: An input magnetic ring connecting plate and an output magnetic ring connecting plate are provided at the input end of the housing, the input magnetic ring connecting plate is connected to the motor, the output magnetic ring connecting plate is connected to the transmission shaft, the magnetic ring of the first encoder is arranged on the input magnetic ring connecting plate, and the magnetic ring of the second encoder is arranged on the output magnetic ring connecting plate; The output magnetic ring connecting plate is located radially inside the input magnetic ring connecting plate, and the magnetic ring of the first encoder and the magnetic ring of the second encoder are located in the same plane.

5. The planetary joint module according to claim 4, characterized in that: The driving board is provided with a sensing chip of the first encoder and a sensing chip of the second encoder.

6. The planetary joint module according to claim 5, characterized in that: A control module is provided on the driving board, and a signal connection is established between the control module and the motor, the sensing chip of the first encoder and the sensing chip of the second encoder.

7. The planetary joint module according to claim 2, characterized in that: The motor is a frameless torque motor, and the primary planetary gear train is built inside the motor.

8. The planetary joint module according to claim 2, characterized in that: The primary planetary gear train and the secondary planetary gear train respectively include a ring gear, and the ring gear includes an inner ring and an outer ring, and the outer ring is made of a lighter material than the inner ring.

9. The planetary joint module according to claim 8, characterized in that: The inner ring is made of alloy steel, and the outer ring is made of aluminum alloy.

10. A robot, characterized in that: A planetary joint module as described in any one of claims 1 to 9 is adopted.

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