High-torque and high-precision ultrasonic motor with self-protection function and implementation mode thereof

Patent metadata

Field	Value
Publication number	US-11764705-B2
Application number	US-202217863907-A
Country	US
Kind code	B2
Filing date	Jul 13, 2022
Priority date	Oct 12, 2021
Publication date	Sep 19, 2023
Grant date	Sep 19, 2023

Abstract

A high-torque and high-precision ultrasonic motor with a self-protection function and an implementation mode of the high-torque and high-precision ultrasonic motor are provided. In the device, a gasket encloses an output shaft of an ultrasonic motor body. A harmonic reducer encloses a shell of the ultrasonic motor body. A motor shaft penetrates through the ultrasonic motor body. The end, close to the motor shaft, of the ultrasonic motor body is defined as a top end, and the bottom end of the motor shaft is sequentially enclosed with an encoder support and a high-precision encoder assembly. The gasket, the harmonic reducer, the encoder support and the high-precision encoder assembly are sequentially arranged from the ultrasonic motor body to the bottom end of the motor shaft. After the ultrasonic motor body decelerates and increases torque, the motor shaft outputs rotating speed and torque.

First claim

What is claimed is:

1. A high-torque and high-precision ultrasonic motor with a self-protection function, comprising an ultrasonic motor body, a gasket, a harmonic reducer, a motor shaft, an encoder support and a high-precision encoder assembly, wherein
the gasket is sleeved on an output shaft of the ultrasonic motor body, the harmonic reducer is sleeved to a shell of the ultrasonic motor body, the motor shaft penetrates through the ultrasonic motor body, an end, close to the motor shaft, of the ultrasonic motor body is defined as a top end, and a bottom end of the motor shaft is sequentially sleeved with the encoder support and the high-precision encoder assembly; and
the gasket, the harmonic reducer, the encoder support and the high-precision encoder assembly are sequentially arranged from the ultrasonic motor body to the bottom end of the motor shaft.

2. The high-torque and high-precision ultrasonic motor with a self-protection function according to claim 1 , wherein the ultrasonic motor body comprises a stator seat, a bearing end cover, a second bearing, a stator assembly, a stator gland, a first bearing, a flexible rotor assembly, a rotor shaft, a pre-pressure adjusting gasket, an auxiliary adjusting gasket, an input friction disc, an output friction disc assembly, an output shaft, a pre-pressure adjusting nut, a shell and a third bearing, a threaded hole coaxial with the motor shaft is formed in the center of the shell close to the bottom end of the motor shaft, and a third bearing is embedded in the pre-pressure adjusting nut and inserted in the threaded hole formed in the center of the shell;
the output shaft is coaxially and fixedly connected with the output friction disc assembly, and the output shaft and the motor shaft coaxially penetrate through the third bearing embedded in the pre-pressure adjusting nut;
a bearing hole coaxial with the motor shaft is formed in the center of the stator seat, the depth of the bearing hole is ½-⅘ of the thickness of the first bearing, the first bearing is embedded in the bearing hole formed in the center of the stator seat, and the rotor shaft and the motor shaft coaxially penetrate through the stator seat and the first bearing; and
the stator assembly is further arranged on the surface of the stator seat, the upper surface of an inner ring of the stator assembly is covered with the stator gland, and the flexible rotor assembly and the input friction disc are sequentially arranged on the surface of the stator assembly and sleeved on the rotor shaft.

3. The high-torque and high-precision ultrasonic motor with a self-protection function according to claim 2 , wherein
the stator assembly comprises a flexible printed board, a piezoelectric ceramic piece and a stator, and the flexible printed board, the piezoelectric ceramic piece and the stator are coaxially and sequentially sleeved on a convex cylinder arranged in the stator seat from the top end of the motor shaft to the bottom end of the motor shaft; and
the flexible rotor assembly comprises a friction material, a rotor and damping rubber, and the friction material, the rotor and the damping rubber are coaxially and sequentially stacked in the direction from the top end of the motor shaft to the bottom end of the motor shaft.

4. The high-torque and high-precision ultrasonic motor with a self-protection function according to claim 3 , wherein
the rotor shaft penetrates through the first bearing and is of a hollow structure, the pre-pressure adjusting gasket is arranged between the first bearing and the rotor shaft, and the auxiliary adjusting gasket is arranged between the first bearing and the flexible rotor assembly.

5. The high-torque and high-precision ultrasonic motor with a self-protection function according to claim 4 , wherein
the bearing gland is arranged at the spigot end, close to the top end of the motor shaft, of the stator seat, and the second bearing is coaxially arranged on the inner side of the bearing gland;
the input friction disc is arranged on the surface of an inner web plate of the rotor and is fixedly connected with the rotor shaft; and
the output friction disc assembly is stacked on the surface of the input friction disc and comprises an output friction disc and a friction plate, and an inner web plate of the output friction disc is fixedly arranged on the output shaft penetrating through the third bearing.

6. The high-torque and high-precision ultrasonic motor with a self-protection function according to claim 2 , wherein
the ultrasonic motor body comprises two friction pairs, the tooth surface of the stator assembly and the friction material surface of the flexible rotor assembly form the first friction pair which is an ultrasonic motor driven friction pair, and the outer ring surface of the input friction disc and the surface of the friction plate of the output friction disc assembly form the second friction pair which is a torque protection device friction pair; and
the torque protection device friction pair is a torque limiting protection device of the ultrasonic motor body.

7. The high-torque and high-precision ultrasonic motor with a self-protection function according to claim 6 , wherein
the harmonic reducer comprises a wave generator, a flexible gear, a steel wheel, a special-shaped bearing and a sealing ring, the wave generator is coaxially sleeved on the output shaft with the central axis of the motor shaft as the central line, and the gasket is arranged between the output shaft and the wave generator;
one end face of the steel wheel is coaxially and fixedly installed on the end face of a special-shaped bearing inner ring, and the other end face of the steel wheel is fixedly connected with a flange plate of the motor shaft; the flexible gear is coaxially and fixedly installed on the end face of a special-shaped bearing outer ring, and meanwhile the special-shaped bearing outer ring and the flexible gear are coaxially and fixedly installed on the shell; and
the sealing ring is embedded between the special-shaped bearing outer ring and the steel wheel.

8. The high-torque and high-precision ultrasonic motor with a self-protection function according to claim 7 , wherein the high-precision encoder assembly comprises an encoder coded disc and an encoder shell;
the encoder coded disc is fixedly arranged at the position, close to the bottom end, of the motor shaft in a sleeving mode, and the coded disc is covered with the encoder shell, wherein the encoder support is coaxially installed on the special-shaped bearing outer ring, and the encoder shell and the encoder support are fixed; and
the encoder shell also comprises an encoder reading head.

9. An implementation mode of the high-torque and high-precision ultrasonic motor with a self-protection function according to claim 1 , wherein the output shaft of the ultrasonic motor body outputs rotating speed and torque to the wave generator of the harmonic reducer, the rotating speed and torque are output through the motor shaft, and the high-precision encoder assembly feeds back the output rotating speed and angle position information of the motor shaft.

10. The implementation mode of the high-torque and high-precision ultrasonic motor with a self-protection function according to claim 9 , wherein the ultrasonic motor body comprises a stator seat, a bearing end cover, a second bearing, a stator assembly, a stator gland, a first bearing, a flexible rotor assembly, a rotor shaft, a pre-pressure adjusting gasket, an auxiliary adjusting gasket, an input friction disc, an output friction disc assembly, an output shaft, a pre-pressure adjusting nut, a shell and a third bearing, a threaded hole coaxial with the motor shaft is formed in the center

Assignees

• Nuaa Super Control Tech Co Ltd
• Univ Nanjing Aeronautics & Astronautics

Inventors

• Yang Lin
• Yang Mojian
• Zhao Chunsheng

Classifications

• H02N2/0065 Primary

  Friction interface (friction linings F16D69/00) · CPC title

• H02N2/163 Primary

  Motors with ring stator · CPC title

• H02N2/12 Primary

  Constructional details · CPC title

• H02N2/10

  producing rotary motion, e.g. rotary motors · CPC title

• H02N2/123

  Mechanical transmission means, e.g. for gearing · CPC title