CN-224209981-U - Joint actuator and gear reducer thereof

Abstract

The utility model discloses a gear reducer which comprises a sun gear shaft, a planet carrier and a gear ring, wherein the sun gear is arranged on the sun gear shaft, the planet carrier comprises an inner planet carrier and an output planet carrier, the inner planet carrier is fixedly connected with the output planet carrier, a plurality of planet gear shafts are arranged between the inner planet carrier and the output planet carrier, a large planet gear meshed with the sun gear and a small planet gear meshed with the gear ring are arranged on the planet gear shafts, and the pitch circle diameter of the large planet gear is larger than that of the small planet gear. The utility model also discloses a joint actuator, which comprises a shell, wherein the shell is internally provided with a motor component and the gear reducer, the motor component comprises a stator and a rotor sleeved in the stator, a central through hole is arranged in the rotor, a transmission piece which rotates synchronously with the rotor is arranged in the central through hole, the transmission piece is in transmission connection with a sun gear shaft, and a gear ring is fixedly arranged in the shell. The joint actuator provided by the utility model can not increase the radial size under the condition of meeting the requirement of large transmission ratio.

Inventors

• YU SANCHENG
• NI ZHONGMING
• LU XIANGHONG
• Chen Hengkun
• XU YINBO

Assignees

• 重庆蓝黛精密部件有限公司

Dates

Publication Date

20260508

Application Date

20250530

Claims (10)

1. 1. The gear reducer is characterized by comprising a sun gear shaft, a planet carrier and a gear ring; The planet carrier comprises an inner planet carrier and an output planet carrier, the inner planet carrier is fixedly connected with the output planet carrier, a plurality of planet wheel shafts are arranged between the inner planet carrier and the output planet carrier, a large planet gear meshed with the sun gear and a small planet gear meshed with the gear ring are arranged on the planet wheel shafts, and the pitch circle diameter of the large planet gear is larger than that of the small planet gear.
2. 2. The gear reducer of claim 1, wherein a relief gap is provided between the inner planet carrier and the output planet carrier for relieving the large planet gear.
3. 3. The gear reducer of claim 1, wherein the output planet carrier is provided with an output flange.
4. 4. The joint actuator is characterized by comprising a shell, wherein a motor assembly and the gear reducer according to any one of claims 1-3 are arranged in the shell, the motor assembly comprises a stator and a rotor sleeved in the stator, a central through hole is formed in the rotor, a transmission piece which rotates synchronously with the rotor is arranged in the central through hole, the transmission piece is in transmission connection with a sun gear shaft, and the gear ring is fixedly arranged in the shell.
5. 5. The joint actuator of claim 4 wherein the housing comprises a shell and an end cap that is mounted to the shell.
6. 6. The joint actuator of claim 5 wherein the drive member comprises a drive shaft, a first bearing is disposed between one end of the drive shaft and the housing, a second bearing is disposed between the second end and the inner planet carrier, and the drive shaft rotates in synchronization with the sun gear shaft.
7. 7. The joint actuator of claim 6 wherein a middle portion of the drive shaft is provided with a drive portion coupled to the rotor.
8. 8. The joint actuator of claim 5 wherein a third bearing is disposed between the end cap and the output carrier, the third bearing being a cross roller bearing.
9. 9. The joint actuator of claim 4 wherein the pitch circle diameter of the large planet gear is: Wherein D 2 is the pitch diameter of the large planetary gear, D 2a is the addendum circle diameter of the large planetary gear, D 1 is the pitch diameter of the sun gear, D is the inner diameter of the housing at the position corresponding to the large planetary gear, and delta is the radial width of the reserved gap between the large planetary gear and the housing.
10. 10. The joint actuator of claim 9 wherein the pitch circle diameter of the pinion gear is: d 3 ＝d 4 ―(d 1 +d 2 ) Wherein d 3 is the pitch diameter of the minor planet gear, and d 4 is the pitch diameter of the gear ring.

Description

Joint actuator and gear reducer thereof Technical Field The utility model belongs to the technical field of robots, and particularly relates to a joint actuator and a gear reducer thereof. Background The robot joint actuator is used as a core power component of a robot system and bears the key function of converting electric energy into mechanical motion, and the performance of the robot joint actuator directly influences the motion precision, the load capacity, the response speed and the overall reliability of the robot. From the technical standpoint, a typical joint actuator is generally composed of modules such as a driving motor, a speed reducing mechanism, a sensor system, a control unit, and the like, which are precisely integrated to realize functions such as torque amplification, motion conversion, closed-loop control, and the like. With the continuous expansion of the application scene of the robot, the performance requirements on the joint actuator are increasingly diversified and severe from industrial manufacturing to medical service, space exploration to home service. The mechanical deceleration type joint actuator has a dominant role in the field of industrial robots for a long time, and is technically characterized in that the reduction of the output rotating speed of a motor and the amplification of torque are realized through a gear meshing principle. The actuator generally adopts a three-stage structure, wherein a high-speed end provides original power for a servo motor, a middle stage realizes variable speed and torque conversion for a precision speed reducer, and an output end integrates a position/torque sensor to form closed-loop control. According to different types of the speed reducing mechanism, the main flow scheme can be divided into three categories of a harmonic speed reducer, a planetary speed reducer and an RV speed reducer, and the three categories have distinct performance characteristics and application scenes. The planetary reducer adopts a multistage gear parallel split structure, has the advantages of high rigidity and large bearing capacity, and is commonly used in large-load industrial robots. However, if the existing planetary reducer is required to realize a larger transmission ratio, the radial dimension is increased, and the application of the planetary reducer in a space-limited scene is limited. Disclosure of Invention In view of the above, an object of the present utility model is to provide a joint actuator and a gear reducer thereof, which can meet the requirement of a large transmission ratio without increasing the radial dimension. In order to achieve the above purpose, the present utility model provides the following technical solutions: The utility model relates to a gear reducer, which comprises a sun gear shaft, a planet carrier and a gear ring; The planet carrier comprises an inner planet carrier and an output planet carrier, the inner planet carrier is fixedly connected with the output planet carrier, a plurality of planet wheel shafts are arranged between the inner planet carrier and the output planet carrier, a large planet gear meshed with the sun gear and a small planet gear meshed with the gear ring are arranged on the planet wheel shafts, and the pitch circle diameter of the large planet gear is larger than that of the small planet gear. Further, a yielding clearance for yielding the large planet gear is arranged between the inner planet carrier and the output planet carrier. Further, an output flange is arranged on the output planet carrier. The utility model also provides a joint actuator, which comprises a shell, wherein a motor assembly and the gear reducer are arranged in the shell, the motor assembly comprises a stator and a rotor sleeved in the stator, a central through hole is formed in the rotor, a transmission piece which rotates synchronously with the rotor is arranged in the central through hole, the transmission piece is in transmission connection with the sun gear shaft, and the gear ring is fixedly arranged in the shell. Further, the housing includes a shell and an end cap that is mounted over the shell. Further, the transmission piece comprises a transmission shaft, a first bearing is arranged between one end of the transmission shaft and the shell, a second bearing is arranged between the second end of the transmission shaft and the inner planet carrier, and the transmission shaft and the sun gear shaft synchronously rotate. Further, a transmission part connected with the rotor is arranged in the middle of the transmission shaft. Further, a third bearing is arranged between the end cover and the output planet carrier, and the third bearing adopts a crossed roller bearing. Further, the pitch circle diameter of the large planetary gear is: Wherein D 2 is the pitch diameter of the large planetary gear, D 2a is the addendum circle diameter of the large planetary gear, D 1 is the pitch diameter of the sun gear, D is the inner diamete