Patent Application
20140319402
Pilot valves are commonly used to provide fluid flow to actuate larger flow valves which can control higher flow rates. The fluid being controlled is most often compressed gas or hydraulic fluid.
While existing valves are suitable for their intended purpose, the need for improvement remains, particularly in providing a pilot control valve that may utilize the structural features of a common piston cylinder to support and actuate the valve.
According to one embodiment of the invention, a valve assembly is provided including a generally hollow cylinder coupled to an axially aligned piston chamber. The cylinder defines an internal void extending from one side of the cylinder to another side of the cylinder. The cylinder includes at least one fluid inlet path and at least one fluid outlet path. A shuttle is arranged within the internal void of the cylinder. The shuttle is slidable between a first position and a second position around an axially located piston rod of the piston chamber. A generally sealed chamber exists between a portion of the shuttle and the cylinder. When the shuttle is in the second position, the chamber fluidly couples the fluid inlet path and the fluid outlet path to provide a controllable fluid flow into and out of the cylinder.
The subject matter, which is regarded as the invention, is particularly pointed out and distinctly claimed in the claims at the conclusion of the specification. The foregoing and other features, and advantages of the invention are apparent from the following detailed description taken in conjunction with the accompanying drawings in which:
The detailed description explains embodiments of the invention, together with advantages and features, by way of example with reference to the drawings.
Reference is made to the following U.S. patent application Ser. No. 13/448,340, filed on Apr. 16, 2012 the entire contents of which are incorporated herein by reference thereto. Reference is also made to U.S. Pat. No. 8,156,655, issued on Apr. 17, 2012, the entire contents of which are also incorporated herein by reference thereto. U.S. Pat. No. 8,156,655 also claims priority to U.S. Provisional Application Ser. No. 60/986,865 filed on Nov. 9, 2007, the entire contents of which are also incorporated herein by reference thereto.
In accordance with exemplary embodiments of the present invention, a fluid valve is disclosed. In an exemplary embodiment, the fluid valve is coupled to a common piston cylinder 1 and is configured to control a flow of compressed gas in a manner similar to a pneumatic switch when operated.
Referring now to
The valve assembly 15 includes a valve shuttle 10 that is slidable relative to an internal void within the cylinder of fluid valve assembly 15. As a result of the contour of the valve shuttle 10, an internal chamber 19 is formed by the space between the surface of the valve shuttle 10 and an internal surface of the valve assembly 15. The internal chamber 19 is fluidly coupled to a fluid inlet port 8 of the fluid valve assembly 15. Shuttle sealing members 14, 16, such as O-rings or an elastomeric diaphragm for example, are positioned adjacent the opposing ends of the valve shuttle 10 and are configured to seal any compressed gas within the internal chamber 19, thereby inhibiting gas flow beyond the chamber 19. Also, arranged within the valve assembly 15, in contact with an end of the pilot valve shuttle 10, is a biasing mechanism 6, such as a compression spring for example, mounted to a spring holder 5. When the fluid valve assembly 15 is in a first, non-operational state, as illustrated in
Referring now to
The fluid valve assembly 15 is transformed from a non-operational state to an operational state by the motion of the piston 18 and the piston rod 13 within the piston cylinder 1. The gas flow and associated motion dynamics of a piston 18 within piston cylinder 1 are known to a person having ordinary skill in the art. In one embodiment, the cylinder of the fluid valve assembly 15 includes a vent hole 17 that allows any compressed gas from the motion of the valve shuttle 10 between the first position and the second position to escape without creating a backpressure that would inhibit movement of the shuttle 10.
The valve assembly 15 is configured to transition between the non-operation and operational states illustrated in the FIGS. When the pneumatic piston rod 13 is moved generally away from the fluid valve assembly 15, the biasing force applied by biasing mechanism 11 on the shuttle 10 is removed. In turn, by releasing the force applied to the shuttle 10, the internal biasing mechanism 6 will bias the valve shuttle 10 back to the first position adjacent the end plate 4. When the valve shuttle 10 returns to the first position, the sealing members 14 and 16 mounted on the valve shuttle 10 are repositioned to again inhibit compressed gas from flowing to exit port 7.
The valve assembly 15 typically actuates at the end of travel of the piston rod 13 when it has moved inwardly toward the piston body. In embodiments where it is desirable to actuate the valve assembly 15 prior to the end of inward travel of the piston rod 13, a spacer or spring, such as biasing mechanism 11 for example, is located around a portion of the piston rod 13 to actuate the valve assembly 15. Inclusion of a spacer or biasing mechanism 11 reduces the distance traveled before the actuating force supplied by piston rod 13 and end effector 12 contacts shuttle 10, and therefore reduces the travel distance required to transform the valve assembly 15 from a non-operational to an operational state.
The valve assembly 15 described herein is a fluid control valve that can function as a fluid switch. The valve assembly 15 utilizes the structural features of a common piston cylinder to support and to actuate the valve, thereby eliminating or substantially reducing the use of additional mounting and actuating hardware. In the exemplary embodiment, the valve assembly 15 is integrally mounted to a piston cylinder 1 and is actuated by the piston rod 13 thereof In addition, the physical relationship between piston cylinder 1 and valve assembly 15 substantially reduces the cost and complexity and alignment problems associated with prior art valves, which utilize additional hardware to separately mount and separately align valves. Another advantage is that the valve assembly 15 may be mounted on either or both ends of a dual ended piston cylinder 1, thereby providing gas switching flow signals at either or both ends, that is, any end of the piston cylinder 1 where the piston rod 13 protrudes.
While the invention has been described in detail in connection with only a limited number of embodiments, it should be readily understood that the invention is not limited to such disclosed embodiments. Rather, the invention can be modified to incorporate any number of variations, alterations, substitutions or equivalent arrangements not heretofore described, but which are commensurate with the spirit and scope of the invention. Additionally, while various embodiments of the invention have been described, it is to be understood that aspects of the invention may include only some of the described embodiments. Accordingly, the invention is not to be seen as limited by the foregoing description, but is only limited by the scope of the appended claims.
This application claims priority to U.S. Provisional Patent Application Ser. No. 61/810,440, filed Apr. 10, 2013, the contents of which are incorporated herein by reference thereto.
| Number | Date | Country | |
|---|---|---|---|
| 61810440 | Apr 2013 | US |
