Pressure Balance Valve

Abstract

The valve includes a first seal seat, a second seal seat, and a fluid flow path across the first seal seat. A seal is in sealing contact with the first seal seat and the second seal seat. An actuator is adjacent to the first seal seat and operable to deflect the seal to permit fluid flow through the flow path. The seal defines a through passageway fluidly connecting the first seal seat to a pressure balance cavity behind the seal in the second seal seat.

Description

[Background technology]

[0001] Liquid rocket engines and other types of engines are powered by one or more combustible fluids that are supplied to a combustion chamber. For example, the fluids may be transported from a storage tank through a series of supply lines to the combustion chamber. The flow rate of the fluids is adjusted depending on the desired operation of the engine. In this regard, one or more flow control valves, such as poppet valves or pintle valves, are known to manage the flow rate of the fluids. Summary of the Invention [Means for solving the problem]

[0002] A valve according to one example of the present disclosure includes a first seal seat, a second seal seat, and a fluid flow path across the first seal seat. A seal is in tight contact with the first seal seat and the second seal seat. An actuator is adjacent to the first seal seat and operable to deflect the seal to permit fluid flow through the flow path. The seal defines a through-passage fluidically connecting the first seal seat to a pressure balance cavity in the second seal seat behind the seal.

[0003] In a further embodiment of any of the foregoing embodiments, the seal has a first seal side in seal with the first seal seat and a second seal side opposite the first seal side in seal with the second seal seat, and the through passage fluidly connects the first seal side and the second seal side.

[0004] In a further embodiment of any of the preceding embodiments, the second seal side remains in intimate contact with the second seal seat even when the actuator is actuated to deflect the seal.

[0005] In a further embodiment of any of the preceding embodiments, the seal is elastomeric.

[0006] In a further embodiment of any of the preceding embodiments, the seal defines a central axis and the through passage is coaxial with the central axis.

[0007] In a further embodiment of any of the preceding embodiments, the first sealing seat is coaxial with the central axis and includes a port through which the pintle portion of the actuator extends.

[0008] In a further embodiment of any of the preceding embodiments, the pintle portion has a through-hole that is coaxial with the central axis and fluidly connected to the through-passage of the seal.

[0009] In a further embodiment of any of the preceding embodiments, the flow passage extends between the pintle portion and the first sealing seat.

[0010] In a further embodiment of any of the foregoing embodiments, the seal is elastomeric and has a first seal side that is in intimate contact with a first seal seat and a second seal side opposite the first seal side that is in intimate contact with a second seal seat. A through passage fluidly connects the first seal side to the second seal side. The seal defines a central axis, and the through passage is coaxial with the central axis. The first seal seat includes a port coaxial with the central axis, through which a pintle portion of the actuator extends. The pintle portion has a throughbore that is coaxial with the central axis and is fluidly connected to the seal's through passage, and a flow passage extends between the pintle portion and the first seal seat.

[0011] A valve according to one example of the present disclosure includes a first seal seat, a second seal seat, and a fluid flow path across the first seal seat. The seal has a closed state in which it seals against the first seal seat to block fluid flow through the flow path and an open state in which it is biased against the first seal seat to allow fluid flow through the flow path. The seal seals against the second seal seat in both the open and closed states. An actuator is adjacent to the first seal seat and is operable to bias the seal to move from the closed state to the open state. The seal defines a through passageway fluidically connecting the first seal seat to a pressure balance cavity behind the seal at the second seal seat. The through passageway allows fluid to flow into the pressure balance cavity in the closed state, creating a pressure balance across the seal.

[0012] In a further embodiment of any of the preceding embodiments, the seal has a first seal side that seals against a first seal seat in the closed state and a second seal side opposite the first seal side that seals against a second seal seat in the open and closed states, and the through passage fluidly connects the first seal side and the second seal side.

[0013] In a further embodiment of any of the preceding embodiments, the seal is elastomeric.

[0014] In a further embodiment of any of the preceding embodiments, the seal defines a central axis and the through passage is coaxial with the central axis.

[0015] In a further embodiment of any of the preceding embodiments, the first sealing seat is coaxial with the central axis and includes a port through which the pintle portion of the actuator extends.

[0016] In a further embodiment of any of the preceding embodiments, the pintle portion has a throughbore coaxial with the central axis and fluidly connected with the through passage of the seal.

[0017] In a further embodiment of any of the preceding embodiments, the flow passage extends between the pintle portion and the first sealing seat.

[0018] The present disclosure may include one or more of the individual features disclosed above and / or below, either alone or in any combination thereof.

[0019] The various features and advantages of the present disclosure will become apparent to those skilled in the art from the following detailed description and drawings, which are not to scale and can be briefly described as follows. [Brief explanation of the drawings]

[0020] [Figure 1] FIG. 2 is a diagram illustrating an example of a pressure balance valve. DETAILED DESCRIPTION OF THE INVENTION

[0021] In this disclosure, where appropriate, identical reference numbers refer to identical elements, and reference numbers increased by 100 or multiples thereof refer to modified elements that are understood to have the same features and advantages as the corresponding elements.

[0022] FIG. 1 schematically illustrates a pressure balance valve 20. The valve 20 may be used, but is not limited to, to control the flow of gaseous or liquid fluids in a rocket engine. The valve 20 generally includes a seal 22 disposed between a first seal seat 24 and a second seal seat 26. The valve 20 defines a flow path (P) across the first seal seat 24 for fluid flow therethrough. Although not shown, the seal 22 and seal seats 24 / 26 are housed within a valve housing, which may also include an inlet port to the valve 20 and an outlet port from the valve 20.

[0023] In this example, the seal 22 is cylindrical and defines a central axis A, but the seal 22 is not limited to this shape and can have a different shape, such as a polyhedron. Each of the seal seats 24 / 26 is an upright ridge having a shape complementary to the shape of the seal 22. For example, in the case of a cylindrical seal 22, the seal seats 24 / 26 are circular. In the case of a polyhedron seal 22, the seal seats 24 / 26 may be polygonal, having the same number of sides as the cross-section of the polyhedron, or the seal seats 24 / 26 may be circular but fit within the cross-section of the polyhedron. The tips of the ridges on the seal seats 24 / 26 function as sealing surfaces. The seal 22 has a first seal side 22a at one axial end and a second seal side 22b at the opposite axial end. In the closed state shown, the first seal side 22a is in intimate contact with the first seal seat 24 to block flow through the flow path P. The second sealing side 22b is in intimate contact with the second sealing seat 26 and maintains sealing contact in both the closed and open states of the valve 20. Thus, the seal 22 is sandwiched between the sealing seats 24 / 26.

[0024] Seal 22 further defines a through-passage 22c from first seal side 22a to second seal side 22b, generally coaxial with axis A. Through-passage 22c fluidly connects first seal seat 24 to a pressure balance cavity 28 in second seal seat 26 behind seal 22. Pressure balance cavity 28 is bounded on its sides by raised portions of second seal seat 26.

[0025] An actuator 30 is provided adjacent the first seal seat 24. The actuator 30 includes a pintle portion 30a and can be electromagnetically actuated via an electric current to move the pintle portion 30a relative to the seal 22. For example, the actuator 30 can be actuated to move the pintle portion 30a toward the seal 22, thereby deflecting the seal 22 from a static home state to a deflected state, as shown by the dashed line L. When the pintle portion 30a is retracted from the seal 22, the seal 22 returns to its home state. In this regard, the seal 22 is made of an elastomer that can elastically recover from the deflected state to its home state. For example, elastomers include, but are not limited to, fluoroelastomers (FKM) and ethylene propylene diene monomers (EPDM).

[0026] The actuator 30 is selectively actuated via electrical current to switch the valve 20 between a closed state and an open state. In the closed state, the pintle portion 30a is retracted and exerts no actuating force on the seal 22. In this state, the seal 22 contacts and seals against the first seal seat 24, blocking (e.g., preventing) flow through the flow path P. When the actuator 30 is actuated to press the pintle portion 30a against the seal 22, the seal 22 deflects, transitioning from the closed state to an open state. In the open state, the deflection of the seal 22 moves it away from the first seal seat 24, thereby permitting flow through the flow path P between the first seal seat 24 and the exterior of the pintle portion 30a, as shown. By controlling the stroke length of the pintle portion 30a, the seal 22 can be deflected by different amounts, increasing or decreasing flow through the flow path P.

[0027] The first seal seat 24 includes a port 24a coaxial with the central axis A. The port 24a is surrounded on its side by a raised portion of the first seal seat 24. A pintle portion 30a extends through the port 24a. The pintle portion 30a includes a through-hole 30b that is also coaxial with the central axis A. The through-hole 30b opens into the flow path P upstream of the first seal seat 24 and is fluidly connected to the pressure balance cavity 28 via the through-hole 22c of the seal 22. Thus, during operation of the valve 20, fluid pressure is applied to both the first seal side 22a and the second seal side 22b. In this regard, when the valve 20 is in a closed state, the areas of the first seal side 22a and the second seal side 22b exposed to the fluid are substantially equal, maintaining pressure balance across the seal 22. That is, the pressure that the fluid exerts on the end of the seal 22 at the first seal seat 24 is equal to the pressure that the fluid exerts on the end of the seal 22 at the second seal seat 26, so the net fluid pressure on the seal 22 is zero.

[0028] This pressure balance makes the valve 20 substantially insensitive to fluid pressure. For example, if the seal 22 did not have the through passage 22c and pressure balance cavity 28, the fluid would only exert pressure on the first seal side 22a near the first seal seat 24. As a result, if the net fluid pressure on the seal 22 were sufficiently high, it could unintentionally deflect the seal 22 and cause a fluid leak. Therefore, the pressure balance within the valve 20 and the valve 20's substantial insensitivity to fluid pressure avoids this problem.

[0029] Although the illustrated examples show combinations of features, not all of them need to be combined to realize the benefits of various embodiments of the present disclosure. In other words, systems designed in accordance with embodiments of the present disclosure do not necessarily include all of the features shown in the figures or all of the parts shown schematically in the figures. Furthermore, selected features of one embodiment can be combined with selected features of other embodiments.

[0030] The foregoing description is exemplary rather than limiting in nature. Variations and modifications to the disclosed examples will become apparent to those skilled in the art that do not necessarily depart from the disclosure. The scope of legal protection given to this disclosure can only be determined by studying the following claims.

Claims

1. a first sealing sheet, a second sealing sheet, and a fluid flow path across the first sealing sheet; a seal in intimate contact with the first sealing sheet and the second sealing sheet; an actuator adjacent the first seal seat and operable to deflect the seal to permit fluid flow through the flow passage; Equipped with The seal defines a through passageway fluidly connecting the first seal seat to a pressure balance cavity behind the seal at the second seal seat.

2. 2. The valve of claim 1, wherein the seal has a first seal side in sealing contact with the first seal seat and a second seal side opposite the first seal side in sealing contact with the second seal seat, and the through passage fluidly connects the first seal side and the second seal side.

3. 3. The valve of claim 2, wherein the second seal side remains in intimate contact with the second seal seat when the actuator is actuated to deflect the seal.

4. 10. The valve of claim 1, wherein the seal is elastomeric.

5. 2. The valve of claim 1, wherein the seal defines a central axis and the through passage is coaxial with the central axis.

6. 6. The valve of claim 5, wherein the first sealing seat includes a port coaxial with the central axis and through which a pintle portion of the actuator extends.

7. 7. The valve of claim 6, wherein the pintle portion has a through-bore coaxial with the central axis and fluidly connected to the through-bore of the seal.

8. 8. The valve of claim 7, wherein the flow passage extends between the pintle portion and the first seal seat.

9. 2. The valve of claim 1, wherein the seal is elastomeric, the seal has a first seal side sealed against the first seal seat and a second seal side opposite the first seal side sealed against the second seal seat, the throughway fluidly connects the first seal side and the second seal side, the seal defines a central axis, the throughway is coaxial with the central axis, the first seal seat includes a port coaxial with the central axis through which a pintle portion of the actuator extends, the pintle portion has a throughbore coaxial with the central axis and fluidly connected to the throughbore in the seal, and the flow passage extends between the pintle portion and the first seal seat.

10. a first sealing sheet, a second sealing sheet, and a fluid flow path across the first sealing sheet; a seal having a closed state in which it seals against the first seal seat to block fluid flow through the flow path and an open state in which it deflects against the first seal seat to allow fluid flow through the flow path, the seal being in close contact with the second seal seat in both the open and closed states; an actuator adjacent the first seal seat and operable to deflect the seal to move from the closed position to the open position; Equipped with the seal defines a through passageway fluidly connecting the first seal seat to a pressure balance cavity in the second seal seat behind the seal, the through passageway, in a closed state, allowing fluid to flow into the pressure balance cavity to create a pressure balance across the seal.

11. 11. The valve of claim 10, wherein the seal has a first seal side that seals against the first seal seat in the closed state and a second seal side opposite the first seal side that seals against the second seal seat in the open state and the closed state, and the through passage fluidly connects the first seal side and the second seal side.

12. 11. The valve of claim 10, wherein the seal is elastomeric.

13. 11. The valve of claim 10, wherein the seal defines a central axis, and the through passage is coaxial with the central axis.

14. 14. The valve of claim 13, wherein the first sealing seat includes a port coaxial with the central axis and through which a pintle portion of the actuator extends.

15. 15. The valve of claim 14, wherein the pintle portion has a throughbore coaxial with the central axis and fluidly connected to the through passage of the seal.

16. 16. The valve of claim 15, wherein the flow passage extends between the pintle portion and the first seal seat.

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