Patent Application
20200131994
This application relates to a method of creating an adaptor sleeve for an existing valve design to modify the existing valve such that it may be used in a new set of operating conditions, or fit in a larger bore.
Valves are utilized in any number of applications. One standard type of valve is a spool valve wherein a piston may be biased by a spring within a sleeve. There are windows in the sleeve that selectively communicate inlet and outlet ports, as the piston strokes through the sleeve.
Valves are typically designed for a particular application. As an example, the timing and desired flow through a particular valve controls the design of the windows.
However, it may be desirable to utilize a valve designed for one application in a distinct application.
A method of modifying an existing valve assembly has the step of placing a supplemental sleeve within a housing. The housing has a housing inlet window and a housing outlet window, and the supplemental sleeve has a sleeve inlet window and a sleeve outlet window. The method includes the step of placing an existing piston-sleeve set within the supplemental sleeve.
A spool valve is also disclosed.
These and other features may be best understood from the following drawings and specification.
The spool valve 24 includes an existing sleeve 30 having an inlet window 32 corresponding to chamber 28 and an outlet window 34 corresponding to chamber 26. A piston 50 is spring-biased by a spring 112 to move along an axis. A window or opening 53 in the piston 50 selectively connects windows 32 and 34. As known, pressurized fluid is supplied to a chamber 54 to cause the spool to move against the force of the spring 112 and control the flow of fluid. Valve 24 can be thought of as an existing valve assembly 202 and fits within a bore 152 in a housing 150.
This allows a valve which has previously been designed for another application to be utilized into this new application and in this larger housing bore. This can allow variation in timing and other characteristics of the valve without requiring a complete design. This can also result in variation in flow characteristics such as flow, volume or pressure.
The piston window 53 would still communicate the existing sleeve inlet window to the existing sleeve outlet window, as originally designed. The supplemental sleeve can either modify a fluid signal such as flow, volume or pressure from the housing inlet window to the existing sleeve inlet window, and/or from the existing sleeve outlet window to the housing outlet window. Alternatively, there need not be any modification in the flow characteristic and merely being received and supported within the large bore is also a benefit of this disclosure.
Also, by utilizing the supplemented sleeve 100, the relative size of the windows 102 and 104 can be changed relative to windows 32 and 34 to achieve a different schedule. As shown, the window 32 has a length 11, while the window 102 has a larger length 12. Similarly, the window 34 has a length 13 whereas the window 104 has a larger length 14. Since the lengths 12 and 14 are shorter than the lengths 11 and 13, the timing and volume of the flow through the valve may be changed to meet a desired application.
One may change the relative sizes of the window to vary the timing of porting from inlet to outlet, or alternatively to maintain existing timing and volume following the modification or repair of the housing.
Using a larger 12 and 14 may provide a same or similar flow volume and pressure, or may slightly modify the pressure drop. It could make the resulting sleeves somewhat lighter. Having a smaller 12 and 14 would allow modifying the performance characteristic of the valve then making windows 102 and 104 in the supplemental sleeve the regulating windows.
While a particular pressure regulating valve for a fuel application in a gas turbine engine is disclosed, the broad teachings of this method could extend to any number of other spool valve and piston valve applications.
A method of modifying an existing valve assembly, comprising the steps of: (a) placing a supplemental sleeve within a housing, wherein the housing has a housing inlet window and a housing outlet window, and the supplemental sleeve has a sleeve inlet window and sleeve outlet window; and
The housing inlet window and the housing outlet window are formed within the main body of a housing. The valve may be a metering valve, having a spring biasing the piston in one direction with the addition of a secondary pressure signal and a primary fluid pressure selectively biasing the piston in a direction opposed to the spring.
Although an embodiment of this invention has been disclosed, a worker of ordinary skill in this art would recognize that certain modifications would come within the scope of this disclosure. For that reason, the following claims should be studied to determine the true scope and content of this disclosure.
