Fluid flow control damper assembly

• US 20020179159A1
• Filed: 04/04/2002
• Published: 12/05/2002
• Est. Priority Date: 04/04/2001
• Status: Active Grant

• Current Assignee: Abco Consulting, Inc.
• Original Assignee: Abco Consulting, Inc.
• Inventors: Zelczer, Alex
• Granted Patent: US 6,817,378 B2
• Time in Patent Office: Days
• US Class Current: 137/601.09
• CPC Class Codes: F15B 15/1428 Cylinders F15B15/1438 takes precedence
• CPC Class Codes: F15B 15/1447 Pistons; Piston to piston rod assemblies
• CPC Class Codes: F16K 1/221 specially adapted operating means therefor operating means per se F16K31/00
• CPC Class Codes: F16K 31/122 the fluid acting on a piston F16K31/143, F16K31/163, F16K31/363, F16K31/383 take precedence
• CPC Class Codes: Y10T 137/87475 Adjacent plate valves always parallel
• CPC Class Codes: Y10T 137/87499 Fluid actuated or retarded

Abstract

A fluid flow control damper assembly having a damper vane and a piston actuator is relatively easy to install when the outer surface of a duct is inaccessible. The piston actuator includes a powder metal piston, lacking an elastomeric (for example, rubber) seal, that is closely received within a glass cylinder. The glass cylinder has a fitting that closes one end of the cylinder and is connectable to a pneumatic control system. A drive rod is connected between the piston and the damper vane to move the damper vane between an open position and a closed position.

Claims

1. A damper assembly comprising:

a housing having a passage therethrough, and a pair of vanes mounted in the housing and movable between an open position and a closed position, wherein when the vanes are in the open position, airflow through the passage is substantially free from interference by the vanes, and when the vanes are in the closed position airflow through the passage is substantially zero.

2. A damper assembly as set forth in claim 1, wherein the damper assembly further comprises an actuator assembly mounted to the housing and connected to the vanes to move the vanes between the open and closed positions.

3. A damper assembly as set forth in claim 2, wherein in the closed position each vane closes half the width of the passage.

4. A damper assembly as set forth in claim 3, wherein the vanes are pivotally mounted to the housing about pivot lines extending near the center of the housing.

5. A damper assembly as set forth in claim 4, wherein in the open position, the vanes are substantially contained within the housing.

6. A damper assembly as set forth in claim 2, wherein the actuator assembly includes an actuator having a piston movable within a cylinder and a linkage interconnecting the vanes and the piston such that movement of the piston in the cylinder causes movement of the vanes.

7. A damper assembly as set forth in claim 6, wherein the actuator, includes a piston-cylinder actuator connected to the linkage;

the piston-cylinder actuator including the piston and the cylinder that have cooperating nonelastomeric sliding sealing surfaces which provide essentially friction-free axial movement of the piston relative to the cylinder.

8. A damper assembly as set forth in claim 7, wherein the cooperating sealing surfaces include a substantially continuous inner circumferential surface of the cylinder, and a substantially continuous outer circumferential surface of the piston.

9. A damper assembly as set forth in claim 6, wherein the piston is formed of a material selected from the group including metal, powdered metal, resin, glass, and polymer.

10. A damper assembly as set forth in claim 9, wherein the sealing surface of the piston has a friction-reducing coating.

11. A damper assembly as set forth in claim 6, wherein the cylinder is formed of a material selected from the group including metal, powdered metal, resin, glass, and polymer.

12. A damper assembly as set forth in claim 11, wherein the sealing surface of the cylinder has a friction-reducing coating.

13. A damper assembly as set forth in claim 6, wherein the piston-cylinder actuator is a pneumatic piston-cylinder actuator.

14. A damper assembly as set forth in claim 13, wherein the piston-cylinder actuator includes a fitting at one end of the cylinder to connect the actuator to a pneumatic control system.

15. A damper assembly as set forth in claim 6, further comprising a bracket that supports the piston-cylinder actuator.

16. A damper assembly as set forth in claim 15, wherein the piston-cylinder actuator includes a fitting at one end of the cylinder that has a threaded portion for mounting the actuator relative to the base.

17. A damper assembly as set forth in claim 1, wherein the damper vanes lie in substantially parallel planes when both damper vanes are in the open position.