BOOSTER PILOT VALVE

Abstract: A booster pilot valve operable at ultra low power levels is provided. The booster valve includes a moveable spool capable of directing a fluid flow to at least two different paths. The booster valve may be coupled to a piezotronic three-way valve, which controls the movement of the spool by redirecting a main fluid flow along different paths to create a force on the spool. The piezotronic valve is capable of actuation at very low power levels such as might be provided by a Profibus PA or other Bus system.

Description: BOOSTER PILOT VALVE RELATION TO COPENDING APPLICATIONS This Non-provisional Application claims the benefit of the Provisional Application No. 60/192, 119 filed March 24, 2000. FIELD OF THE INVENTION This invention relates generally to valve actuating methods and apparatus and, more particularly, to booster pilot valves. BACKGROUND AND SUMMARY OF THE INVENTION In recent years, industrial facilities, such as pharmaceutical or petrochemical plants, employ low-energy Bus systems to operate and control various processes. The low-energy Bus systems operate with currents ranging from 1.5 to 10 mA at an input voltage of 6 to 30 volts. The low-energy Bus systems consume less power than previously used operating and control systems. The use of low-energy Bus systems may reduce the overall operating expenses of the plants, among other advantages. With the introduction of low-energy Bus systems has also come a demand for valves that operate with the limited power supply of the Bus system. Large valves typically require a considerable amount of power to open and close, more power than may be available through the low-energy Bus system. Consequently, it has become a common practice to mount an air-powered cylinder on or near a large valve to actuate it. The air cylinder is often actuated by a solenoid or a pilot valve that is in communication with the air cylinder. The pilot valve requires much less power than conventional valve actuators. Therefore, it is desirable to design a pilot valve that operates at the extremely low power levels of low-energy Bus systems to actuate a larger valve. In addition, it is desirable that the pilot valve be compatible with a particular Bus system being used in a plant. The present invention is directed to providing a booster pilot valve operating at very low power levels to actuate a larger valve. SUMMARY OF THE INVENTION In accordance with one aspect of the present invention, a booster pilot valve includes a body and a hydraulic member. The body defines a fluid chamber. The hydraulic member is disposed in the fluid chamber and is movable by a pressurized flow between a first and a second position. The hydraulic member in the first position permits a cylinder port to communicate with a first ancillary port. The hydraulic member in the second position pennits the pressurized flow to communicate with the cylinder port. In a further embodiment, the booster pilot valve includes a secondary device operable to direct the pressurized flow. In accordance with another aspect of the present invention, a booster pilot valve includes a body and a spool. The body defines a fluid chamber having a main port and an outlet port. The spool is disposed within the fluid chamber and is movable by a pressurized flow between a closed position and an opened position. The spool in the closed position permits a secondary flow form a cylinder port to communicate with a first ancillary port. The spool in the opened position permits the pressurized flow from the main port to communication with the cylinder port. In a further embodiment, the booster pilot valve includes a secondary valve communicating with the outlet port of the body. The secondary valve is operable to direct the pressurized flow entering the main port to move the spool to the closed or opened position. The secondary valve may include a three-way valve or may include a piezotronic valve. In accordance with yet another aspect of the present invention, a booster pilot valve includes a body and a hydraulic member. The body defines a fluid chamber and includes a main port and a stem. The main port is defined in a first end of the fluid chamber, and the stem protrudes into the fluid chamber from a second end. The stem defines an outlet port aligned with the main port. The hydraulic member is disposed in the fluid chamber and is movable between opened and closed positions within the fluid chamber. The hydraulic member includes first and second surfaces and a fluid passageway. The first surface is adjacent to the first end of the fluid chamber. The second surface is adjacent to the second end of the fluid chamber. The fluid passageway is defined in the hydraulic member and extends from the first surface to the second surface. The stem is partially disposed within the fluid passageway so that the fluid passageway communicates the main port with the outlet port. The hydraulic member in the opened position permits fluid communication of the main port with a cylinder port. The hydraulic member in the closed position permits fluid communication between the cylinder port and a first ancillary port. In accordance with a further aspect of the present invention, a method of operating a valve element with a hydraulic device includes: supplying a pressurized flow into the hydraulic device; directing the pressurized flow to the valve element by selectively concentrating the pressurized flow to move the hydraulic device to an opened position; and directing a secondary flow from the valve element to an ancillary port in the hydraulic device by selectively concentrating the pressurized flow to move the hydraulic device to a closed position. The foregoing summary is not intended to summarize each potential embodiment, or every aspect of the invention disclosed herein, but merely to summarize the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS The present invention, including a preferred embodiment and other aspects, will be best understood with reference to the detailed description of specific embodiments of the invention, which follows, when read in conjunction with the accompanying drawings, in which: FIG. 1 illustrates a side view of a booster pilot valve in accordance with one aspect of the present invention. FIG. 2 illustrates a cross-sectional, detailed view of the booster pilot valve according to FIG. 1 taken along line A-A. FIG. 3A schematically illustrates the booster pilot valve in a first or closed position in relation to a main valve; FIG. 3B schematically illustrates the booster pilot valve in a second or opened position in relation to the main valve; FIG. 4 illustrates a cross-sectional view of the booster pilot valve according to FIG. 1 taken along line B-B. FIG. 5 illustrates a cross-sectional view of the booster pilot valve according to FIG. 1 taken along line C-C. FIG. 6 illustrates a cross-sectional view of the booster pilot valve according to FIG. 1 taken along line D-D. FIG. 7 illustrates a top view of the booster pilot valve according to the present invention; FIG. 8 illustrates a bottom view of the booster pilot valve according to the present invention; and FIG. 9 illustrates a perspective view of the booster pilot valve connected to a larger valve. While the invention described herein is susceptible to various modifications and alternative forms, only specific embodiments have been shown by way of example in the drawings and will be described in detail herein. However, it should be understood that the invention is not to be limited to or restricted by the particular forms disclosed herein. DETAILED DESCRIPTION OF THE INVENTION Referring to FIG. 1, a side view of a booster pilot valve illustrates one embodiment of the present invention. The booster pilot valve includes a primary valve and a secondary device. The primary valve facilitates connection with a main valve (not shown) and includes an adapter and a body. The adapter and the body portion may comprise stainless steel or other materials. The body portion may also be adapted to connect directly to a fluid source such as pressurized air. The body connects to the adapter at a first end. In the present embodiment, the diameter of body is smaller than the diameter of adapter at the first end. Located around the periphery of primary valve are an adapter recess and a body recess. Adapter recess circumscribes the adapter, and body recess circumscribes the body. Adapter recess and body recess receive seals and, respectively. The seals and, which are preferably O-ring seals, seal an annulus formed between primary valve and a main valve (not shown) when the two are connected. The secondary device is attached to the primary valve. The secondary device includes a secondary valve, which is preferably a three-way valve. More particularly, the secondary valve may preferably be a three-way piezotronic valve. In order to operate the booster pilot valve, the piezotronic valve must have compatible electronics (not shown) to accept signals from an operating platform or a network Bus (not shown). In one embodiment, the booster pilot valve may be provided with a Profibus PA operator, but other operators compatible with other Bus systems, including, but not limited to, Profibus DP, Fieldbus Foundation and DeviceNet may also be used. The operation of the primary valve, however, may not change with any alterations in electronics. With the benefit of this disclosure, one of skill in the art will recognize that the piezo-operated three-way valve may be obtained from the Automated Switch Company (ASCO), but other three-way valves may also be used. The piezotronic valve advantageously requires very little power to operate, on the order of 100 mW with currents in the range of approximately 1.5 to 10 mA, which can be provided by the low-energy Bus system. The piezotronic valve is shrouded by a cover. An electrical connector extends from cover for connection to a power source or the Bus system. The piezotronic valve and any additional electronics may also be encapsulated in epoxy within the cover for protection from the environment. Referring to FIG. 2, a cross-section of the primary valve of FIG. 1 taken along line A-A further illustrates the present invention. As before, the primary valve includes the body connected to the adapter. The primary valve further includes a hydraulic member or spool. For simplicity, the fasteners and apertures for connecting the adapter, the body and the secondary device have been omitted from FIG. 2. The adapter includes a first adapter portion and a second adapter portion. The first adapter portion connects to the secondary device, and the second adapter portion connects to the body. The first adapter portion includes the adapter recess circumscribing its periphery. The first adapter portion further includes a protrusion or stem, an outlet port and a fluid passageway. The protrusion projects from the first adapter portion into a first internal bore in the second adapter portion. The outlet port extends from a distal end of the protrusion to an opening, which communicates with the secondary device and more specifically with the piezotronic valve. The second adapter portion is connected to the first adapter portion. The second adapter portion defines the first internal bore that accommodates the protrusion or stem of the first adapter portion. The first internal bore has a greater diameter than that of the protrusion so that a second plenum is formed therebetween. The fluid passageway is shown with dashed line to illustrate fluid communication between the piezotronic valve and the second plenum. The actual location of the fluid passageway may be on a dihedral plane to the cross-sectional plane of FIG. 2. Furthermore, additional ancillary ports (not shown) may communicate the piezotronic valve with the second plenum. The second adapter portion further includes an annular extension extending therefrom. The annular extension includes a second internal bore, which communicates with the first internal bore but has a lesser diameter. The body includes the body recess and further includes a main port and cylinder ports. The body defines an internal bore having a first bore portion, a first shoulder, a second bore portion, and a second shoulder. The body is connected to the second adapter portion so that the annular extension is disposed in the first bore portion. A decrease in diameter at the first shoulder forms the second bore portion that communicates with the first bore portion. The main port communicates with the second bore portion at the second shoulder, and the cylinder ports communicate with the first bore portion at the first shoulder. The bores of the body and the internal bores of the adapter define a fluid chamber within the primary valve. The hydraulic member or spool, which may be constructed of stainless steel or other materials, is disposed within the fluid chamber of the primary valve and is movable therein. Specifically, the spool is partially disposed and movable within internal bore of the second adapter portion and partially disposed and movable within the internal bore of the annular extension. The spool is also partially disposed and movable within the second bore portion of the body. The spool includes a first surface, a second surface and a fluid passageway. A first end of the spool exhibits the first surface adjacent to the shoulder of the fluid chamber. A first plenum of the fluid chamber is defined between the first surface and the shoulder. A second end of the spool exhibits the second surface within the fluid chamber. The second plenum is further defined between the second surface and the portion of the fluid chamber in the adapter. In the present embodiment, the second surface exhibits a greater surface area than the first surface. The greater surface area of the second surface results in part from an increasing diameter of the spool. The diameter of the spool increases at a shoulder to approximately match the internal bore of the annular extension. The spool also exhibits another increase in diameter at a shoulder so that the second end approximately matches the internal bore of the first adapter portion. The fluid passageway provides for fluid communication through the interior of the spool and extends from the first surface to the second surface . The protrusion or stem of the first adapter portion is partially disposed within the fluid passageway. A filter (not shown) may be disposed in the passageway. The filter may be commercially available and may filter particles, for example, to approximately fifty microns. The fluid passageway communicates the main port with the outlet port of the primary valve. Thus, fluid (not shown) may communicate between the main port and the three-way piezotronic valve. The primary valve contains a plurality of seals used for both the connection and engagement of the components. Referring concurrently to FIGS. 2, the adapter includes the seal's, which are preferably O-ring seals. The first adapter seal seals the connection of the first adapter portion to the second adapter portion. The second adapter seal seals engagement of the protrusion with the fluid passageway of the spool. The third adapter seal seals the connection between the adapter and the body. The fourth adapter seal seals connection of the annular extension with the first internal bore of the body. The hydraulic member or spool includes a plurality of seals for the engagement of the spool with the fluid chamber of the primary valve. The spool includes a seal, which is preferably a U-cup seal, and includes the seals, which are preferably O-ring seals. The U-cup seal, disposed in an annular recess, seals engagement of the spool with the internal bore of the second adapter portion. The U-cup seal seals off fluid contained in the second plenum. The seal seals the engagement between the spool and the annular extension when the spool is appropriately positioned within the fluid chamber. With the spool in a first position as shown in FIGS. 2 and 3A, the seal lacks engagement with the internal bore. Fluid communication is thus permitted from the cylinder ports to a first annulus between the spool and the adapter extension. When the spool is moved to a second position as shown in FIG. 3B, the seal engages the internal bore of the annular extension and seals the fluid communication of the cylinder ports with the first annulus. The seal seals the engagement of the spool with the second bore portion of the body when the spool is appropriately positioned within the fluid chamber. Further details regarding the engagement of the seals in the primary valve are provided below with reference to FIGS. 3A and 3B. In a general description of the operation of the primary valve, pressurized fluid (not shown) may enter the fluid chamber of the primary valve though the main port. The pressurized fluid may concentrate in the first plenum. With the application of pressure from the pressurized fluid to the first surface, a first force may be produced that urges the spool to move within the fluid chamber and distance from the shoulder. The pressurized fluid may also pass through the fluid passageway and into the piezotronic valve via the outlet port. The pressurized fluid may be directed by the piezotronic valve to the second plenum via the fluid passageway. With the application of pressure from the pressurized fluid to the second surface, a second force may be produced that urges the spool to move within the fluid chamber and distance from the first adapter portion. Fluid in the second plenum may be further vented by communicating the piezotronic valve with the adapter recess via a first ancillary port at the adapter recess. Moreover, when the spool is in the second or closed position as shown in FIG. 2, a second fluid flow (not shown) may communicate from the cylinder ports to the first annulus, to an opening, to a second annulus, to a second ancillary port and to the body recess. The first annulus is formed between the spool and the annular extension. The opening is defined in the annular extension of the second adapter portion. The opening communicates the first annulus with the second annulus. The second annulus is formed between the annular extension and the first internal bore of the body. Only one opening is shown, but a number of similar openings may be formed circumscribing the annular extension. The second ancillary port communicates the second annulus with the body recess, where the second fluid may be vented. Further details regarding the movement of the spool, the flow of fluid and the operation of the booster pilot valve are provided below with reference to FIGS. 3 A and 3B. Referring now to FIGS. 3A-3B, the operation of the booster pilot valve is schematically illustrated. As before, the booster pilot valve includes the primary valve connected to the secondary device. The primary valve includes the adapter, the body and the movable spool as described above. The secondary device includes a secondary valve, which is shown here schematically. The secondary valve is preferably a three-way valve requiring low power levels to operate, such as the piezotronic valve as discussed above. In some embodiments, the booster pilot valve may be used in series with at least one other pilot operated valve, such as the main valve of FIGS. 3A-3B. The booster pilot valve may be capable of operating at very low power levels, but may not be able to provide an adequate flow rate of pressurized fluid to actuate a large valve in a reasonable time period. Therefore, the booster pilot valve may only actuate another pilot operated valve, which may in turn directly actuate a large valve or in some cases may actuate yet another pilot operated valve. One advantage of the booster pilot valve, however, is that it can operate at even the lowest Bus power levels, and thus begin a "stepping up" process to other pilot valves. The other pilot valve can eventually provide the necessary flow rate of pressurized fluid to ultimately operate the large valve. In other embodiments, the booster pilot valve may be the only pilot valve used. The primary valve connects to a main valve. The main valve communicates a pressurized working fluid PF to the primary valve via a main line. The pressured fluid PF represents a main flow ultimately intended to operate a large-valve actuator (not shown) or other pilot valve, such as main valve. Conventional pilot valves use flow that is controlled by or flows through only the pilot valve itself. Advantageously, the booster pilot valve of the present invention uses the pressurized flow PF to also influence the orientation of the spool, which in turn redirects the path of pressurized fluid PF in the manner described below. The main valve also communicates a second fluid CF from a cylinder (not shown) via cylinder lines. The cylinder lines communication the cylinder fluid CF between the cylinder and the booster pilot valve. The cylinder may also be in communication with main valve or other valves, and the cylinder may be, but is not limited to, a reservoir used to open/close another valve or to extend/retract a piston. The cylinder fluid CF may come from a closing cylinder (not shown) for the piloted valve or from an actuator volume (not shown) that is being exhausted. Referring to FIG. 3A, the pressurized fluid PF is constantly supplied from the main valve. The pressurized fluid PF enters the booster pilot valve through the main port and is permitted to concentrate within the first plenum between the first surface and the shoulder. The pressure of the fluid PF is transmitted to the lower surface of the spool. Consequently, the pressurized fluid PF acting against the area of the lower surface creates a first force F x on the spool. The pressurized fluid PF is also permitted to pass through the fluid passageway to the piezotronic valve via the outlet port. In FIG. 3A, the piezotronic valve is de-energized and communicates the pressurized fluid PF from the outlet port to the second plenum via the fluid passageway. The pressurized fluid PF is permitted to concentrate in the second plenum and apply pressure to the second surface. Consequently, a second force F 2 is produced on the spool that opposes the first force F x . The area of the second surface is preferably greater than the area of the first surface. Therefore, the second force F 2 on the spool is larger than the first force F,. The force differential (F 2 - Fj) tends to urge the spool to a first or closed position illustrated in FIG. 3 A when the piezotronic valve is de-energized. Designing the areas of the first and second surfaces to urge the spool to the first or closed position with the pressurized fluid PF and to overcome frictional forces is well within the ordinary skill of one in the art. With the spool in the first or closed position, the seal seals the fluid communication of the main port from the cylinder ports. The seal lacks sealed engagement with the annular extension of the adapter. Consequently, the cylinder ports are in fluid communication with the first annulus between the spool and the adapter, and the cylinder fluid CF is permitted to flow from the cylinder ports to the first annulus. From the first annulus, the cylinder fluid CF is permitted to flow through the opening in the adapter extension and into the second annulus created between the adapter extension and the body. Finally, the cylinder fluid CF may vent to the atmospheric pressure through the second ancillary port in the body recess. Thus, by de-energizing the three- way piezotronic valve, the spool of the booster pilot valve may be moved to the first or closed position with the pressurized fluid PF and may vent the cylinder fluid CF when the cylinder closes. Referring now to FIG. 3B, the path of the pressurized fluid PF within the booster pilot valve has been altered to actuate the main valve or some other valve for which main valve is a pilot. As schematically illustrated, the piezotronic valve is energized. The flow of pressurized fluid PF is restricted at the outlet port by the piezotronic valve, and the pressurized fluid PF is permitted to concentrate in the fluid chamber of the primary valve. In addition, a new flow path is created by the three-way piezotronic valve between the fluid passageway and the first ancillary port. The first ancillary port leads to atmospheric pressure at the adapter recess, enabling any pressurized fluid PF trapped in the second plenum to escape. With the fluid passageway in fluid communication with the first ancillary port, the force on the second surface subsides and only the Force F x on the first surface predominates. Consequently, the Force F t urges the spool into a second or opened position as shown in FIG. 3B. As the spool moves within the fluid chamber, the seal disengages the second bore portion of the body, and the seal engages the internal bore of the adapter extension. A gap is created between the spool and the body, which facilitates fluid communication of the pressurized fluid PF from the main port to the cylinder ports. The pressurized fluid PF is permitted to flow through the gap to the cylinder ports. The pressurized fluid PF may further act on a pressure area to drive the spool the remaining stroke within the fluid chamber. The pressurized fluid PF is then directed out of the cylinder ports, through the cylinder lines in the main valve and to the cylinder. The pressurized fluid PF may provide working pressure to actuate the main valve that may be in communication with the cylinder. Thus, by energizing the three-way piezotronic valve, the spool of the booster pilot valve may be moved to the second or opened position with the pressurized fluid PF and may actuate another larger valve. Referring now to FIGS. 4-9, the embodiment of the booster pilot valve is illustrated in a number of principle views. In the discussion that follows and for the sake of brevity, only certain features are described for each view. The same reference numerals are used in the FIGS. 4-9 to represent the same components in each view. In FIGS. 4-6, the embodiment of the booster pilot valve is illustrated in various cross-sections. FIG. 4 illustrates a cross-sectional view of the booster pilot valve according to FIG. 1 taken along line B-B. FIG. 5 illustrates a cross-sectional view of the booster pilot valve according to FIG. 1 taken along line C-C. FIG. 6 illustrates a cross- sectional view of the booster pilot valve according to FIG. 1 taken along line D-D. In FIGS. 7-9, the embodiment of the booster pilot valve is illustrated in a top view, a bottom view and a perspective view respectively. The secondary device may include a push button activation system. The system may include a manual push button, a spring, and a gasket. The manual push button may be included on the cover to activate the piezotronic valve. The spring returns the push button to the deactivated position shown in the figures. The button includes stems to guide the movement of the button within the cover. The gasket may be provided between the piezotronic valve and the button. Bolts may attach the piezotronic to the primary valve. With the benefit of this disclosure, it will be understood by one of skill in the art that the push button activation system may be omitted. Particularly illustrated in FIGS. 5 and 6, the seals as described in FIG. 2 are illustrated at differing points of cross-section than illustrated in FIG. 2. The cylinder port is shown in cross-section communicating with the first shoulder. Additionally, the opening defines a radial bore in the annular extension. The opening communicates fluid from the first annulus formed between the spool and adapter extension to the second annulus formed between the adapter extension and the body as described above. In the bottom view of FIG. 8, the location of the main port and cylinder ports are illustrated in the bottom of the body. Also, the PC board holding the piezotronic valve (not shown) and additional electronics (not shown) is visible within the cover. Particularly illustrated in FIG. 9, the booster pilot valve is shown connected to a larger valve. The booster pilot valve may pilot the larger valve; however; it will be understood by one of skill in the art with the benefit of this disclosure that booster pilot valve is not limited to piloting the larger valve, but may pilot other valves as well. While the invention has been described with reference to the preferred embodiments, obvious modifications and alterations are possible by those skilled in the related art. Therefore, it is intended that the invention include all such modifications and alterations to the full extent that they come within the scope of the following claims or the equivalents thereof.

Claims: CLAIMS: 1. A booster pilot valve, comprising: a body defining a fluid chamber; and a hydraulic member disposed in the fluid chamber and movable by a pressurized flow between a first and a second position; wherem the hydraulic member in the first position permits a cylinder port to communicate with a first ancillary port, and wherein the hydraulic member in the second position permits the pressurized flow to communicate with the cylinder port. 2. The booster pilot valve of claim 1, further comprising a secondary device operable to direct the pressurized flow. 3. The booster pilot valve of claim 2, wherein the hydraulic member defines a fluid passageway extending from a first surface to a second surface and communicating a main port with an outlet port defined in the body, the main port communicating with the pressurized flow and the outlet port communicating with the secondary device. 4. The booster pilot valve of claim 3, wherein the body comprises a stem having the outlet port and partially disposed within the fluid passageway of the hydraulic member. 5. The booster pilot valve of claim 4, wherein the secondary device directs the pressurized flow to the second surface and urges the hydraulic member to the first position. 6. The booster pilot valve of claim 5, wherein the secondary device directs the pressurized flow to the first surface and urges the hydraulic member to the second position. 7. A booster pilot valve, comprising: a body defining a fluid chamber having a main port and an outlet port; and a spool disposed within the fluid chamber and movable by a pressurized flow between a closed and an opened position; wherein the spool in the closed position permits a secondary flow form a cylinder port to communicate with a first ancillary port, and wherein the spool in the opened position permits the pressurized flow from the main port to communication with the cylinder port. 8. The booster pilot valve of claim 7, further comprising a secondary valve communicating with the outlet port of the body and operable to direct the pressurized flow entering the main port to move the spool to the closed or opened position. 9. The booster pilot valve of claim 8, wherein the secondary valve comprises a three-way valve. 10. The booster pilot valve of claim 8, wherein the secondary valve comprises a piezotronic valve. 11. The booster pilot valve of claim 10, wherein the piezotronic valve comprises a Bus operator to accept signals from a network Bus. 12. The booster pilot valve of claim 10, wherein the piezotronic valve operates using a current supply of approximately 1.5 mA to 10mA. 13. The booster pilot valve of claim 12, wherein the piezotronic valve operates using a power supply of approximately 100m W. 14. The booster pilot valve of claim 7, wherein the spool is engaged with the fluid chamber of the body with a plurality of seals. 15. The booster pilot valve of claim 7, wherein the spool defines a fluid passageway extending from a first surface to a second surface and communicating the main port to the outlet port. 16. The booster pilot valve of claim 15, wherein the body comprises a protrusion having the outlet port and partially disposed in the fluid passageway of the spool at the second surface. 17. The booster pilot valve of claim 16, wherein the pressurized flow concentrated on the second surface moves the spool to the closed position. 18. The booster pilot valve of claim 17, wherein the pressurized flow concentrated on the first surface moves the spool to the opened position. 19. A booster pilot valve, comprising: a body defining a fluid chamber, comprising: a main port defined in a first end of the fluid chamber, and a stem protruding into the fluid chamber from a second end, the stem defining an outlet port aligned with the main port; and a hydraulic member disposed in the fluid chamber and movable between an opened and a closed position within the fluid chamber, comprising: a first surface adjacent to the first end of the fluid chamber; a second surface adjacent to the second end of the fluid chamber, and a fluid passageway defined in the hydraulic member and extending from the first surface to the second surface, the stem partially disposed within the fluid passageway so that the fluid passageway communicates the main port with the outlet port; wherein the hydraulic member in the opened position permits fluid communication of the main port with a cylinder port, and wherein the hydraulic member in the closed position permits fluid communication between the cylinder port and a first ancillary port. 20. The booster pilot valve of claim 19, further comprising a three-way valve in fluid communication with the fluid chamber via the outlet port. 21. The booster pilot valve of claim 20, wherein the three-way valve comprises a piezotronic valve. 22. The booster pilot valve of claim 20, wherein the three-way valve is operable to concentrate a pressurized flow from the main port to a first plenum defined between the first surface and the first end to move the hydraulic member to the opened position. 23. The booster pilot valve of claim 20, wherein the three-way valve is operable to concentrate the pressurized flow from the main port to a second plenum defined between the second surface and the second end to move the hydraulic member to the closed position. 24. The booster pilot of claim 23, wherein a passageway in the body communicates the three-way valve with the second plenum for applying the pressurized flow to the second surface. 25. The booster pilot of claim 24, wherein a second ancillary port in the body communicates with the three-way valve for venting the pressurized flow from the second plenum. 26. The booster pilot valve of claim 19, wherein the hydraulic member is engaged with the fluid chamber with a plurality of seals. 27. The booster pilot valve of claim 26, wherein a first seal seals the main port from the cylinder port when the hydraulic member is in the closed position. 28. The booster pilot valve of claim 27, wherein a second seal seals the cylinder port from the first ancillary port when the hydraulic member is in the opened position. 29. A method of operating a valve element with a hydraulic device, comprising: supplying a pressurized flow into the hydraulic device; directing the pressurized flow to the valve element by selectively concentrating the pressurized flow to move the hydraulic device to an opened position; and directing a secondary flow from the valve element to an ancillary port in the hydraulic device by selectively concentrating the pressurized flow to move the hydraulic device to a closed position. 30. The method of claim 29, wherein selectively concentrating the pressurized flow to move the hydraulic device to the opened or closed position comprises operating a three-way valve communicating the pressurized fluid with the hydraulic device. 31. The method of claim 30, wherein moving the hydraulic device to the opened or closed position comprises applying the pressurized flow to a first or a second surface of the hydraulic device. 32. The method of claim 30, wherein directing the pressurized flow to the valve element comprises sealing the secondary flow from communicating with the ancillary port. 33. The method of claim 30, wherein directing the secondary flow to the ancillary port comprises sealing the pressurized flow from communicating with the valve element.

Inventors: LA MARCA DREW, VOLZ GREGORY J, LA MARCA, DREW, VOLZ, GREGORY, J.
Applicants: ASCO CONTROLS L P, ASCO CONTROLS, L.P.
Application year: 2001
Main classification: F15B
IPC codes: F15B13, F15B21, F16K11, F16K31