Rotary piston type actuator

Patent metadata

Field	Value
Publication number	US-10030679-B2
Application number	US-201614992845-A
Country	US
Kind code	B2
Filing date	Jan 11, 2016
Priority date	Feb 27, 2013
Publication date	Jul 24, 2018
Grant date	Jul 24, 2018

Abstract

A rotary actuator includes a first housing defining a first arcuate chamber having a first cavity, a first fluid port in fluid communication with the first cavity, and an open end. A rotor assembly is rotatably journaled in the first housing and having a rotary output shaft and a first rotor arm extending radially outward from the rotary output shaft. An arcuate-shaped first piston is disposed in the first housing for reciprocal movement in the first arcuate chamber through the open end, wherein a first seal, the first cavity, and the first piston define a first pressure chamber, and a first portion of the first piston contacts the first rotor arm.

First claim

What is claimed is:

1. A plural unitarily mounted cylinder type rotary actuator comprising:
a first housing defining:
a first arcuate chamber having a first open end; and
a second arcuate chamber having a second open end and oriented in the opposite rotational direction as the first arcuate chamber;

a rotor assembly rotatably journaled in said first housing and comprising a rotary output shaft and a first rotor arm extending radially outward from the rotary output shaft; and
a unitary piston assembly comprising an arcuate-shaped first piston and an arcuate-shaped second piston, disposed in said first housing for reciprocal movement in the first arcuate chamber through the first open end and for reciprocal movement in the second arcuate chamber through the second open end, wherein a first seal, the first cavity, and the first piston define a first pressure chamber, a second seal, the second cavity, and the second piston define a second pressure chamber, and a first portion of the unitary piston assembly contacts the first rotor arm.

2. The rotary actuator of claim 1 , wherein the second piston is oriented in the opposite rotational direction as the first piston.

3. The rotary actuator of claim 1 , wherein application of pressurized fluid to the first pressure chamber urges the first piston partially outward from the first pressure chamber to urge rotation of the rotary output shaft in a first direction, and rotation of the rotary output shaft in a second direction opposite that of the first direction urges the first piston partially into the first pressure chamber to urge pressurized fluid out the first fluid port.

4. The rotary actuator of claim 1 , wherein application of pressurized fluid to the first pressure chamber urges the first piston partially outward from the first pressure chamber to urge rotation of the rotary output shaft in a first direction, and application of pressurized fluid to the second pressure chamber urges the second piston partially outward from the second pressure chamber to urge rotation of the rotary output shaft in a second direction opposite from the first direction.

5. The rotary actuator of claim 1 , wherein the first seal is disposed about an interior surface of the first open end.

6. The rotary actuator of claim 1 , wherein the second seal is disposed about an interior surface of the second open end.

7. The rotary actuator of claim 1 , wherein the first seal is disposed about the periphery of the first piston.

8. The rotary actuator of claim 1 , wherein the second seal is disposed about the periphery of the second piston.

9. The rotary actuator of claim 1 , wherein the first seal provides load bearing support for the first piston.

10. The rotary actuator of claim 1 , wherein the first housing is formed as a one-piece housing.

11. The rotary actuator of claim 1 , wherein at least one of the first seal and the second seal is a one-piece seal.

12. The rotary actuator of claim 1 , wherein at least one of the first piston and the second piston is solid in cross-section.

13. The rotary actuator of claim 1 , wherein at least one of the first piston and the second piston is at least partly hollow in cross-section.

14. The rotary actuator of claim 13 , wherein a structural member inside a selected one of the first piston is located between two cavities inside the selected piston.

15. The rotary actuator of claim 1 , wherein at least one of the first piston and the second piston has one of a square, rectangular, ovoid, elliptical, or circular shape in cross-section.

16. The rotary actuator of claim 1 , the first housing further defines a first fluid port in fluid communication with the first cavity and a second fluid port in fluid communication with the second cavity.

17. The rotary actuator of claim 1 , wherein the first arcuate chamber and the second arcuate chamber define at least a portion of an ellipse having a plane, wherein a rotational axis of the output shaft is not perpendicular to the plane.

18. A rotary actuator comprising:
a first housing defining:
a first arcuate chamber comprising a first cavity and an open end, wherein the first housing defining the first arcuate chamber is formed from a single piece of material; and
a second arcuate chamber comprising a second cavity, and a second fluid port in fluid communication with the second cavity;

an arcuate-shaped first piston disposed in said first housing for reciprocal movement in the first arcuate chamber through the open end, wherein a first seal, the first cavity, and the first piston define a first pressure chamber; and
an arcuate-shaped second piston disposed in said first housing for reciprocal movement in the second arcuate chamber and oriented in the same rotational direction as the first piston, wherein a second seal, the second cavity, and the second piston define a second pressure chamber.

19. The rotary actuator of claim 18 , wherein application of pressurized fluid to the first pressure chamber urges the first piston partially outward from the first pressure chamber.

20. The rotary actuator of claim 18 , further comprising a second housing disposed about the first housing and having a second fluid port, wherein the first housing, the second housing, the seal, and the first piston define a second pressure chamber.

21. The rotary actuator of claim 20 , wherein application of pressurized fluid to the first pressure chamber urges the first piston partially outward from the first pressure chamber in a first direction, wherein application of pressurized fluid to the second pressure chamber urges the first piston partially into the first pressure chamber in a second direction opposite from the first direction.

22. The rotary actuator of claim 18 , wherein the first seal is disposed about an interior surface of the open end.

23. The rotary actuator of claim 18 , wherein the first seal is disposed about the periphery of the first piston.

24. The rotary actuator of claim 18 , wherein the first seal provides load bearing support for the first piston.

25. The rotary actuator of claim 18 , wherein the first seal is a one-piece seal.

26. The rotary actuator of claim 18 , wherein the first piston is solid in cross-section.

27. The rotary actuator of claim 18 , wherein the first piston is at least partly hollow in cross-section.

28. The rotary actuator of claim 27 , wherein a structural member inside the first piston is located between two cavities inside the first piston.

29. The rotary actuator of claim 18 , wherein the first piston has one of a square, rectangular, ovoid, elliptical, or circular shape in cross-section.

Assignees

• Woodward Inc

Inventors

• Kim Joseph H
• O'Hara Robert P
• Hydari Shahbaz H
• Sobolewski Pawel A

Classifications

• F15B15/125 Primary

  of the curved-cylinder type · CPC title

• F15B15/06 Primary

  for mechanically converting rectilinear movement into non- rectilinear movement · CPC title

• B64C13/40

  using fluid pressure · CPC title