Magneto-rheological series elastic actuator

Patent metadata

Field	Value
Publication number	US-10626944-B2
Application number	US-201815942256-A
Country	US
Kind code	B2
Filing date	Mar 30, 2018
Priority date	Apr 14, 2017
Publication date	Apr 21, 2020
Grant date	Apr 21, 2020

Abstract

The present disclosure discloses an actuator, comprising a first torsion spring body and a second torsion spring body, each of the first torsion spring body and the second torsion spring body comprising: an inner ring; an outer ring; and a plurality of elastic units, connected in parallel between the inner ring and the outer ring. An outer ring of the first torsion spring body and an outer ring of the second torsion spring body are rigidly connected, and an inner ring of the first torsion spring body and an inner ring of the second torsion spring body are aligned with each other. The actuator further includes a motor element and a braking element. The motor element is for providing an output torque, and is connected with the inner ring of the first torsion spring body. The braking element is for providing a braking torque, and is connected with the inner ring of the second torsion spring body.

First claim

What is claimed is:

1. An actuator, comprising:
a first torsion spring body; and
a second torsion spring body,
each of the first torsion spring body and the second torsion spring body comprising:
an inner ring;
an outer ring; and
a plurality of elastic units, connected in parallel between the inner ring and the outer ring;
the outer ring of the first torsion spring body and the outer ring of the second torsion spring body being rigidly fastened, and the inner ring of the first torsion spring body and the inner ring of the second torsion spring body being aligned,
a motor element for providing an output torque, and connected with the inner ring of the first torsion spring body; and
a braking element for providing a braking torque, and connected with the inner ring of the second torsion spring body.

2. The actuator according to claim 1 , wherein the actuator further comprises a power transmission element, the motor element is connected with the inner ring of the first torsion spring body through the power transmission element.

3. The actuator according to claim 2 , wherein the power transmission element is a planetary gearbox.

4. The actuator according to claim 1 , wherein angle sensors are respectively set at the inner ring of the first torsion spring body and an end distal from the corresponding outer ring, and the inner ring of the second torsion spring body and an end distal from the corresponding outer ring, to measure a deformation difference generated by the inner ring of the first torsion spring body and the inner ring of the second torsion spring body.

5. The actuator according to claim 4 , wherein the angle sensors comprise one or more of an absolute encoder, an incremental encoder and/or a potentiometer.

6. The actuator according to claim 1 , wherein the braking element comprises:
a rotating shaft, made of a high permeability magnetic material, and an end of the rotating shaft is connected with the inner ring of the second torsion spring body;
a coil, wound around the rotating shaft; and
a cavity, for accommodating a fluid,
wherein the fluid is capable of generating a shear stress under an electromagnetic field effect induced by the coil.

7. The actuator according to claim 6 , wherein an axial section profile of the rotating shaft is a curve and/or a segmented polyline.

8. The actuator according to claim 6 , wherein the rotating shaft is an iron core rotating shaft.

9. The actuator according to claim 6 , wherein the fluid is a magneto-rheological fluid.

10. The actuator according to claim 6 , wherein a plurality of pairs of an inner silicon steel sheet and an outer silicon steel sheet are arranged in the cavity, and the fluid is distributed in an overlapping area between the inner silicon steel sheets and the outer silicon steel sheets.

11. The actuator according to claim 10 , wherein the inner silicon steel sheets and the outer silicon steel sheets are designed in a disc form.

12. The actuator according to claim 6 , wherein two electrode ends of the coil are led out through a carbon brush respectively.

13. The actuator according to claim 6 , wherein the actuator further comprises a transmission gear set, and a first transmission gear in the transmission gear set is connected with the other end of the rotating shaft.

14. The actuator according to claim 13 , wherein the transmission gear set comprises one or more of a bevel gear, a spur gear and/or a worm gear.

15. An actuator, comprising:
a motor element, for providing an output torque;
a magneto-rheological braking element, for providing a braking torque; and
a torsion spring, connected in series between the motor element and the magneto-rheological braking element, to provide a flexible connection between the motor element and the magneto-rheological braking element, wherein the torsion spring comprises a first torsion spring body and a second torsion spring body, each of the first torsion spring body and the second torsion spring body comprises:
an inner ring;
an outer ring; and
a plurality of elastic units, connected in parallel between the inner ring and the outer ring;
wherein, the outer ring of the first torsion spring body and the outer ring of the second torsion spring body are rigidly fastened, and the inner ring of the first torsion spring body and the inner ring of the second torsion spring body are aligned.

16. The actuator according to claim 15 , wherein the magneto-rheological braking element comprises:
a rotating shaft, made of a high permeability magnetic material, and an end of the rotating shaft is connected with the inner ring of the second torsion spring body;
a coil, wound around the rotating shaft; and
a cavity, for accommodating a magneto-rheological fluid,
wherein the magneto-rheological fluid is capable of generating a shear stress under an electromagnetic field effect induced by the coil.

17. The actuator according to claim 16 , wherein the actuator further comprises a transmission gear set for changing a torque transmission direction, and a first transmission gear in the transmission gear set is connected with the other end of the rotating shaft.

18. The actuator according to claim 17 , wherein the transmission gear set comprises one or more of a bevel gear, a spur gear and/or a worm gear.

19. The actuator according to claim 16 , wherein an axial section profile of the rotating shaft is a curve and/or a segmented polyline.

20. The actuator according to claim 16 , wherein two electrode ends of the coil are led out through a carbon brush respectively.

21. The actuator according to claim 15 , wherein the actuator further comprises a power transmission element, the motor element is connected with the inner ring of the first torsion spring body through the power transmission element.

22. The actuator according to claim 21 , wherein the power transmission element is a planetary gearbox.

23. The actuator according to claim 15 , wherein angle sensors are respectively set at the inner ring of the first torsion spring body and an distal away from the corresponding outer ring, and the inner ring of the second torsion spring body and an end distal from the corresponding outer ring, to measure a deformation difference generated by the inner ring of the first torsion spring body and the inner ring of the second torsion spring body.

Assignees

• Univ Hong Kong Chinese

Inventors

• Liao Wei-Hsin
• Chen Bing
• Qin Ling
• Zhao Xuan
• Ma Hao

Classifications

• H02K7/10

  Structural association with clutches, brakes, gears, pulleys or mechanical starters · CPC title

• F16F1/3821 Primary

  characterised by adaptations to counter torsional forces · CPC title

• H02K7/1163

  where at least two gears have non-parallel axes without having orbital motion · CPC title

• A61H2003/043

  with a drive mechanism · CPC title

• F16F3/00

  Spring units consisting of several springs, e.g. for obtaining a desired spring characteristic ({F16F1/32, F16F1/34, F16F7/14 take precedence } ; if including fluid springs F16F5/00, F16F13/00) · CPC title