Apparatus to bias a moveable tube towards a seal

Patent metadata

Field	Value
Publication number	US-10337639-B2
Application number	US-201715678646-A
Country	US
Kind code	B2
Filing date	Aug 16, 2017
Priority date	Aug 16, 2017
Publication date	Jul 2, 2019
Grant date	Jul 2, 2019

Abstract

Apparatus are disclosed to bias a tube towards a seal. An example apparatus includes a pneumatic actuator having a diaphragm plate, a yoke housing, and a tube. The tube conveys pressurized fluid between the yoke housing and the diaphragm plate, wherein a first end of the tube extends through a first seal gland in the diaphragm plate to form a seal against an outer surface of the tube and a second end of the tube extends through a second seal gland in the yoke housing to form a seal against the outer surface of the tube. The first end of the tube has a first cross-sectional area that is greater than a second cross-sectional area of the second end of the tube to bias the tube toward the yoke housing during operation of the pneumatic actuator.

First claim

What is claimed is:

1. A pneumatic actuator comprising:
a diaphragm plate;
a yoke housing; and
a tube to convey pressurized fluid between the yoke housing and the diaphragm plate, wherein a first end of the tube extends through a first seal gland in the diaphragm plate to form a seal against an outer surface of the tube and a second end of the tube extends through a second seal gland in the yoke housing to form a seal against the outer surface of the tube, and wherein the first end of the tube has a first cross-sectional area that is greater than a second cross-sectional area of the second end of the tube to bias the tube toward the yoke housing during operation of the pneumatic actuator.

2. The pneumatic actuator of claim 1 , wherein the tube has a step change in cross-sectional area between the first cross-sectional area and the second cross-sectional area.

3. The pneumatic actuator of claim 1 , wherein the tube has a tapered change in cross-sectional area between the first cross-sectional area and the second cross-sectional area.

4. The pneumatic actuator of claim 1 , wherein the first end of the tube is slidably coupled to the first seal gland and the second seal gland.

5. The pneumatic actuator of claim 1 , wherein a first passageway of the first seal gland and a second passageway of the second seal gland are shaped to enable lateral movement of the tube.

6. The pneumatic actuator of claim 5 , wherein the first seal gland or the second seal gland includes an O-ring.

7. The pneumatic actuator of claim 1 , wherein the tube has a cylindrical shape.

8. A pneumatic actuator comprising:
a diaphragm plate;
a yoke housing;
a tube to convey pressurized fluid between the yoke housing and the diaphragm plate; and
means for biasing the tube toward the yoke housing during operation of the pneumatic actuator.

9. The pneumatic actuator of claim 8 , wherein the tube has a step change in cross-sectional area between a first cross-sectional area of a first end and a second cross-sectional area of a second end.

10. The pneumatic actuator of claim 8 , wherein the tube has a tapered change in cross-sectional area between a first cross-sectional area of a first end and a second cross-sectional area of a second end.

11. The pneumatic actuator of claim 8 , wherein the means for biasing the tube toward the yoke housing is a difference in surface areas between a first end and a second end.

12. The pneumatic actuator of claim 8 , wherein the tube has a cylindrical shape.

13. The pneumatic actuator of claim 8 , wherein a first passageway of a first seal gland and a second passageway of a second seal gland are shaped to enable lateral movement of the tube.

14. The pneumatic actuator of claim 13 , wherein the first seal gland or the second seal gland includes an O-ring.

15. A pneumatic actuator comprising:
a tube to convey pressurized fluid between a yoke housing and a diaphragm plate having a first end and a second end opposite the first end, wherein the first end of the tube has a first cross-sectional area that is greater than a second cross-sectional area of the second end of the tube to bias the tube toward the yoke housing during operation of the pneumatic actuator.

16. The pneumatic actuator of claim 15 , wherein the tube has a step change in cross-sectional area between the first cross-sectional area and the second cross-sectional area.

17. The pneumatic actuator of claim 15 , wherein the tube has a tapered change in cross-sectional area between the first cross-sectional area and the second cross-sectional area.

18. The pneumatic actuator of claim 15 , wherein the pressurized fluid conveys a first force on the first end and a second force on the second end, the first force greater than the second force.

19. The pneumatic actuator of claim 15 , wherein a first passageway of a first seal gland and a second passageway of a second seal gland are shaped to enable lateral movement of the tube.

20. The pneumatic actuator of claim 19 , wherein the first seal gland or the second seal gland includes an O-ring.

Assignees

• Fisher Controls Int Llc

Inventors

• Jackson Trenton Frank

Classifications

• F16K31/1262 Primary

  one side of the diaphragm being spring loaded · CPC title

• F16K27/02

  of lift valves (for reducing the flow resistance of screw-spindle lift-valves F16K1/06) · CPC title

• F16K31/1264

  with means to allow the side on which the springs are positioned to be altered · CPC title

• F16K31/126

  the fluid acting on a diaphragm, bellows, or the like (F16K31/145, F16K31/165, F16K31/365, F16K31/385 take precedence) · CPC title