Patent Publication Number: US-2023147379-A1

Title: Variable pressure control valve

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims the benefit of Indian Provisional Patent Application No. 202111050731, filed on Nov. 5, 2021, the disclosure of which is incorporated herein by reference in its entirety. 
     TECHNICAL FIELD 
     The present disclosure relates generally to a system and method of controlling pressure conditions during fuel tank activities, specifically to pressure-operated control valves that respond to fuel pressure. 
     BACKGROUND 
     Various systems and devices are used to control back pressure during filling of aircraft fuel tanks. Aircrafts are adapted for inflight refueling and have a fuel duct or manifold that can lead to a number of separate fuel tanks. 
     In aircraft refueling operations, a service vehicle is connected to a refueling hose to pump fuel into an aircrafts fuel tanks. While connected, there may be fuel pressure in the fuel line. This fuel pressure is monitored and controlled by hose end control valves (HECV). The hose end control valves provide pressure limitation at an outlet to protect aircrafts from over pressurization and surge while refueling. The hose end control valves admit fuel into the fuel tank while open and automatically close in response to the rise in back pressure in the manifold or fuel duct when the fuel tank is full. 
     Hose end control valves are capable of operating at multiple pressure ratings. As such, customers can choose from a variety of pressure settings to tailor control systems to their requirements. These pressure settings are important to prevent damage to fuel tanks or dangerously high-pressure surges in the fuel line. 
     Typically, to change pressure settings of a HECV, the customer would disassemble the HECV in order to replace a spring inside the HECV chamber with a different spring that has a load requirement for achieving a different pressure setting. This can be time consuming and inefficient. 
     Accordingly, there is a need for a variable hose end control valve whereby various pressure settings are achievable simply and quickly without disassembling the hose end control valve. 
     SUMMARY 
     The present disclosure relates to variable Hose End Control Valves (HECVs) that provide pressure limitation to protect an aircraft while refueling. The variable HECV is a single device that can provide different pressure settings to tailor to a customer&#39;s control system without having to disassemble the HECV to replace an internal spring that achieves a different pressure setting. That is, unlike traditional HECVs that require the use of multiple springs to achieve different pressure ratings, the variable HECV has a compensator that can vary compression of a single spring allowing for spring adjustment within the variable HECV to achieve the desired pressure rating without disassembling the variable HECV. 
     One aspect of the present disclosure relates to a valve assembly for controlling fluid flow. The valve assembly includes a valve body that has an inlet end and an outlet end. The valve body defines a chamber and a piston is positioned within the chamber and is movable between an open position to open the valve body and a closed position to close the valve body. A spring is mounted (e.g., captured) between the piston and a spring adjustment member and functions to bias the piston toward an open position. A portion of the spring adjustment member is accessible through the inlet end of the valve body so as to be engageable by a tool to facilitate rotation of the spring adjustment member to vary compression of the spring for setting a spring pressure rating. In certain examples, back-pressure from the outlet end acts on the piston against the bias of the spring to move the piston to a closed position when the backpressure exceeds a pressure limit set by a load setting of the spring. 
     Another aspect of the present disclosure relates to a valve assembly for controlling flow from a pressurized source to a tank. The valve assembly includes a valve body that has an inlet end and an outlet end. The valve body defines fluid passages for receiving fluid flow between the inlet and outlet ends. A piston is mounted within the valve body to control the fluid flow. The piston is movable between an open position and a closed position. A cap member mounts at the inlet end of the valve body. 
     A compensator device is housed within the cap member. The cap member mounts the compensator device within the valve body. The compensator device is accessible through the inlet end of the valve. 
     A spring is between the piston and the compensator device. The spring biases the piston toward the open position and the spring is compressed when the piston moves to the closed position. One end of the spring can be received within the cap. The compensator device is configured to axially rotate relative to the cap to vary compression of the spring to achieve a desired spring pressure rating. In one example, the compensator device is coupled to the cap by a threaded connection. In one example, the cap can plug an end of a spring chamber (e.g., a centrally located passage in which the spring, the cap and the piston are at least partially positioned) adjacent the inlet end of the valve. 
     A further aspect of the present disclosure relates to a valve assembly for controlling flow of liquid from a pressured supply into a tank. The valve assembly includes a valve body that has an inlet end and an opposite outlet end. A piston is operative to close the valve assembly in response to a rise in fluid back pressure when a predetermined liquid level is reached in the tank. A spring is mounted (e.g., captured) between the piston and a spring adjustment member. A portion of the spring adjustment member is accessible through the inlet end of the valve body so as to be engageable by a tool to facilitate axial movement of the spring adjustment member to vary compression of the spring to achieve a spring pressure rating. 
     These and other features and advantages will be apparent from a reading of the following detailed description and a review of the associated drawings. A variety of additional aspects will be set forth in the description that follows. The aspects can relate to individual features and to combinations of features. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the broad concepts upon which the examples disclosed herein are based. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings, which are incorporated in and constitute a part of the description, illustrate several aspects of the present disclosure. A brief description of the drawings is as follows. 
         FIG.  1    is a perspective view depicting an outlet end of a variable pressure control valve in accordance with principles of the present disclosure. 
         FIG.  2    is a perspective view depicting an inlet end of the variable pressure control valve of  FIG.  1   . 
         FIG.  3    is an outlet end view of the variable pressure control valve of  FIG.  1   . 
         FIG.  4    is a cross-sectional view taken along line  4 - 4  of  FIG.  3   . 
         FIG.  4 A  is a cross-sectional view of the variable pressure control valve of  FIG.  4    with a compensator set at a first pressure-setting position and the variable pressure control valve in an open position. 
         FIG.  4 B  is a cross-sectional view of the variable pressure control valve of  FIG.  4    with the compensator set at the first pressure-setting position and the variable pressure control valve in a closed position. 
         FIG.  5    is an enlarged view of a portion of  FIG.  4   . 
         FIG.  6    is a perspective view depicting an inlet end view of a cap and compensator device in accordance with the principles of the present disclosure. 
         FIG.  7    is a perspective view depicting an outlet end view of the cap and compensator device of  FIG.  6   . 
         FIG.  8    illustrates an exploded view showing the compensator device of  FIGS.  6  and  7    exploded from the cap. 
         FIG.  9    illustrates the compensator device of  FIGS.  6  and  7    from the perspective of the inlet end of the valve. 
         FIG.  10    illustrates the compensator device of  FIGS.  6  and  7    from the perspective of the outlet end of the valve. 
         FIG.  11    is a cross-sectional view of the variable pressure control valve of  FIG.  4    showing the valve in an open position with the compensator set at a second pressure-setting position. 
         FIG.  12    is a cross-sectional view of the variable pressure control valve of  FIG.  4    showing the valve in a closed position with the compensator set at the second pressure-setting position. 
         FIG.  13    is a perspective view of another example variable pressure control valve in accordance with the principles of the present disclosure, the example includes two housing pieces. 
         FIG.  14    is an exploded view of the variable pressure control valve of  FIG.  13   . 
         FIG.  15    is a cross-sectional view of the variable pressure control valve of  FIG.  13    showing a cap, a compensator device, spring and piston in accordance with the principles of the present disclosure. 
         FIG.  16    is an enlarged view of a portion of  FIG.  15   . 
         FIG.  17    is an exploded view showing the cap and compensator device of  FIG.  15   . 
         FIGS.  18 - 19    are perspective views illustrating the compensator device of  FIG.  15    mounted within the cap. 
         FIG.  20    is a cross-sectional view of the variable pressure control valve of  FIG.  15    showing the piston in an open position and the compensator at a first pressure-setting position. 
         FIG.  21    is a cross-sectional view of the variable pressure control valve of  FIG.  20    showing the piston in a closed position and the compensator at a first pressure-setting position. 
         FIG.  22    is a cross-sectional view of the variable pressure control valve of  FIG.  15    showing the piston in the open position and the compensator device axially moved to a second pressure-setting position to further compress the spring. 
         FIG.  23    is a cross-sectional view of the variable pressure control valve of  FIG.  22    showing the piston in the closed position and the compensator device axially moved to the second pressure-setting position. 
     
    
    
     DETAILED DESCRIPTION 
     The present disclosure relates to a variable pressure control valve designed to react to changes in outlet pressure to protect an aircraft during refueling. Pressure limiting is a function of a spring housed within the variable pressure control valve that loads a piston (e.g., a slidable member that can be pressure driven) to limit pressure sensed at the variable pressure control valve outlet. 
     The advantageous feature of the variable pressure control valve according to the present disclosure is the ability to provide a variety of pressure ratings suitable for refueling of fuel receiving tanks such as those mounted in airplanes. The variable pressure control valve eliminates the need for disassembly to change out one spring for another to achieve a different pressure setting. As such, it is not necessary to provide multiple springs or valves to tailor control systems to a customer&#39;s requirements. Rather, the variable pressure control valve of the present disclosure includes a spring adjustment member to change compression of a single spring to achieve varied pressure ratings without disassembly of the variable pressure control valve. 
       FIGS.  1 - 3    illustrate a variable pressure control valve  10  (e.g., a pressure regulator valve or a hose end control valve) in accordance with the principles of the present disclosure. The variable pressure control valve  10  includes a valve body  12  with an inlet end  14  and an opposite, outlet end  16 . The valve body  12  is preferably formed of cast metal, such as, aluminum. In the example depicted, the valve body  12  is a single housing, although alternatives are possible. In other examples, the variable pressure control valve  10  may include two separate housing pieces (see  FIG.  13   ). 
     The valve body  12  defines a fluid passage arrangement  18  with fluid passages  20  (see  FIG.  4   ) for receiving fluid flow between the inlet and outlet ends  14 ,  16 . The fluid passages  20  extend about a central region of the valve body as the passages  20  extend between the inlet and outlet ends  14 ,  16 . The inlet end  14  of the valve body  12  is provided with a collar structure  22  for mating with a hose (not shown) of a fuel tank supply. A variety of inlet fittings (e.g., threaded fittings) or quick disconnect adapters are available to mate industry standard hose connections at the inlet end  14  of the valve body  12 . 
     A nozzle (not shown), such as Eaton&#39;s Carter product line nozzle models 64348, 64200, 64201, or 64349, can be mated at the outlet end  16  of the valve body  12  to directly interface with an underwing of an aircraft for fueling. A variety of threaded outlet adapter fittings may also be available for alternative installations away from a nozzle. 
     The variable pressure control valve  10  includes a piston  24  visible through the outlet end  16  of the valve body  12 . The piston  24  is slidably mounted within the valve body  12  between an open position (see  FIG.  4 A ) and a closed position (see  FIG.  4 B ). The piston  24  is configured to limit pressure sensed at the outlet end  16  of the valve body  12  or inlet of a nozzle on which the variable pressure control valve  10  is mounted. That is, the piston  24  is designed to react to changes of outlet pressure or back pressure on the aircraft side to close the valve if the back pressure reaches a predetermined level/limit during fueling with the predetermined level/limit being set by an amount of compression of a spring of the valve. The amount of compression of the spring can be adjusted via a compensator of the valve. 
     During fueling of a stationary aircraft, fuel under pressure from a fuel source is permitted to pass through a hose and the variable pressure control valve  10  connected thereto. Next, fuel passes through a fuel line and nozzle upon opening of the variable pressure control valve  10  to enter fuel tanks mounted under wings of the aircraft. The aircraft fuel tanks can be filled with fuel, at which point, the piston  24  of the variable pressure control valve  10  moves to the closed position to prevent further delivery of fuel into the fuel line. That is, while the fuel tanks are being filled to a desired level, fuel pressure in the line can rise such that the fuel will be forced to surge and the position of the piston  24  is moved to the closed position so as to cut off the flow of fuel. When fuel pressure is equalized again, the piston  24  can be opened in preparation of another fueling operation. The open position being the default state of the variable pressure control valve  10 . 
     The variable pressure control valve  10  helps to maintain a desirable flow of fuel at a predetermined constant pressure. A typical pressure range can be from 35 to 50 pounds per square inch (psi). The variable pressure control valve  10  is designed to control pressure when the back or downstream fuel pressure becomes within range of its control. 
     Turning to  FIGS.  4 ,  4 A,  4 B  cross-sectional views of the variable pressure control valve  10  is depicted. The variable pressure control valve  10  is configured to limit pressure as a function of a spring  26  mounted within the valve body  12 . In certain examples, the spring  26  can be a helical compression spring that compresses on application of a load. The spring  26  loads the piston  24  of the variable pressure control valve  10 . Biasing force exerted on the piston  24  is by the spring  26  which urges the piston  24  towards its open position. Back pressure changes during fueling can urge the piston  24  toward its closed position in opposition to the spring  26 . That is, the piston  24  is operative to close the variable pressure control valve  10  in response to a rise in fluid back pressure when a predetermined liquid level is reached in the tank. 
     The piston  24  can include a head portion  28  and a shaft portion  30 . The variable pressure control valve  10  can include a fixed sleeve  32  bolted within the valve body  12  via fasteners  34  to support the shaft portion  30  of the piston  24 . When the back pressure from the aircraft becomes within control of the variable pressure control valve  10 , the piston  24  can be urged toward the closed position such that the head portion  28  bottoms out and seals against a shoulder  36  of the valve body  12 . Once sealed, the piston  24  closes off the fluid passages  20  to stop the flow of fuel. The shoulder  36  can include circumferential grooves  38  for receiving O-ring type sealing members  40  or any other suitable sealing mechanism. The O-ring sealing members  40  can be made of Teflon or the like, a well-known material of low coefficient of friction. As depicted in  FIG.  5   , the piston  24  is supported relative to the valve body  12  via an annular, split spring ring  42  (e.g., a bearing that also provides sealing and can include an annular seal) and is limited in its sliding movement by a piston ring  44 . 
     A hollow plug or cap  46  can be positioned within the valve body  12  adjacent the inlet end  14 . A central spring passage (e.g., a spring cavity  92 ) is defined within the valve body  12  and is sealed relative to the passage arrangement  18 . An end of the central spring passage adjacent the inlet end  14  of the valve body  12  is closed by the cap  46 . In certain examples, the cap  46  can be in threaded connection with the valve body  12 , although alternatives are possible. In other examples, the cap  46  may be connected to the valve body  12  via a quick disconnect assembly such as a snap ring. 
     Turning to  FIGS.  6 - 7   , the cap  46  includes a main body  48  and an extension portion  50  that extends from the main body  48 . The extension portion  50  of the cap  46  defines a cylindrical recess  52 . In certain examples, when the cap  46  is connected to the valve body  12  and the piston  24  is in the closed position, the recess  52  can receive the shaft portion  30  of the piston  24  and can function as a piston guide or cylinder. In other examples, a shaft portion of a piston may not engage or contact a cap mounted in the valve body. For example, piston  24   a  shown in  FIG.  23    does not engage or contact any portion of cap  46   a  when spring  26   a  is in a maximum compression state. An end of the spring  26  can be contained in the recess  52 . 
     The extension portion  50  can be provided with external threads  54  that threadedly engage internal threads of the valve body  12  to provide a threaded connection  56  (see  FIG.  4   ). For example, internal threads of the valve body  12  can be adjacent the inlet end  14  for receiving the extension portion  50  of the cap  46  to threadedly engage the external threads  54  thereof. 
     The main body  48  of the cap  46  has an external wrench interface  59  such as flats that permits applying torque to the cap  46  when connecting to the valve body  12 . Once the cap  38  is completely secured within the valve body  12 , the main body  48  of the cap  46  can be positioned flush with a shoulder  58  (see  FIG.  4   ) of the valve body  12 . 
     Turning to  FIGS.  8 - 10   , the variable pressure control valve  10  includes a compensator device  60  (e.g., an adjuster nut, a spring adjustment member) which can be mounted within the recess  52  of the cap  46 . The compensator device  60  is generally T-shaped with a head portion  62  and a stem portion  64 . The head portion  62  can be rounded, as shown. The compensator device  60  can be secured within the cap  46  via a threaded connection  66  (see  FIG.  4   ). The head portion  62  can have fine pitch threads  68  formed on an outer surface  70  thereof to facilitate precision axial movement of the compensator device  60  within the cap  46 . That is, the fine pitch threads  68  allow the compensator device  60  to be adjusted gradually or in small increments relative to the cap  46 . The fine pitch threads  68  of the compensator device  60  threadedly engage internal threads  72  (see  FIG.  7   ) formed in the cap  46  to provide the threaded connection  66 . In one example, the threading between the cap  46  and the valve body  12  can be opposite threaded as compared to the threaded connection  66  between the compensation device  60  and the cap  46 . 
     The main body  48  of the cap  46  defines an opening  74  for receiving the stem portion  64  of the compensator device  60 . Thus, the stem portion  64  extends through the main body  48  and can be accessible at the input end  14  of the valve body  12  when the adapter/fitting is removed from the variable pressure control valve  10 . A seal can be provided between the stem portion  64  and the cap  46  at the opening  74  for providing sealing between the cap  46  and the stem portion  64 . 
     Referring again to  FIG.  4 A , the spring  26  is depicted with minimal load (e.g., zero load) being applied thereon. That is, the head portion  62  of the compensator device  60  can be bottomed out inside of the cap  46  to be flushed therewith such that zero load is applied on the spring  26 . When the compensator device  60  is in this far left position relative to the cap  46 , the spring has a 35 psi-compression rating. When it is desired to change the spring pressure rating to something higher, the compensator device  60  can be adjusted axially to apply a load on the spring  26  to meet customer control pressure requirements. Of course, depending upon application, springs having other ranges of pressure ratings could also be used. 
     Referring to  FIGS.  11 - 12   , the spring  26  is biased between the compensator device  60  and the piston  24 . The compensator device  60  is designed to control how much the spring  26  is pressurized by axially changing position of the compensator device  60  inside the cap  46 . That is, the compensator device  60  can be turned clockwise or counterclockwise about a central axis X relative to the cap  46  to axially move from the bottomed-out position shown in  FIG.  4 A  to compress the spring  26  to meet required pressure ratings. As such, the compensator device  60  eliminates the need to have separate springs with different pressure ratings for various applications. With the compensator device  60 , a single spring  26  can be used to achieve different pressure ratings. As such, the variable pressure control valve  10  can be used with various applications without disassembly. 
     The stem portion  64  of the compensator device  60  can include a visual indicator  76  at a distal end  78  thereof. In certain examples, the visual indicator  76  includes multiple indication grooves  76   a ,  76   b ,  76   c  circumferentially defined on the stem portion  64  of the compensator device  60  to indicate a specific pressure setting, although alternatives are possible. For example, the indication grooves  76   a - c  can represent pressure ratings 45, 48, and 50 psi, respectively. 
     The stem portion  64  defines a torque transmitting feature  80  such as a hex feature adjacent the visual indicator  76  for turning the compensator device  60 . The torque transmitting feature  80  of the compensator device  60  can be accessible through the inlet end  14  of the valve body  12  once an operator removes a hose fitting or adapter mounted on the variable pressure control valve  10 . Once the hose adapter/fitting is removed from the inlet end  14  of the variable pressure control valve  10 , an operator may take a tool, such as a screwdriver, wrench, or an Allen key, and insert it into the torque transmitting feature  80  of the stem portion  64  to threadedly adjust the compensator device  60  axially. The compensator device  60  can be turned or rotated clockwise or counterclockwise about the central axis X to make fine adjustments relative to the cap  46  to set the spring  26  to a desired pressure rating. Turning the compensator device  60  to either the left or right may either decrease the space between the compensator device  60  and the piston  24  so that the spring  26  is smaller (i.e., tight, compressed) or increase the space between the compensator device  60  and the piston  24  so that the spring  26  is larger (i.e., looser). 
     The compensator device  60  can be turned until the desired indication groove  76   a - c  is flush with an outer surface  82  of the cap  46  to set the spring pressure rating at either 45, 48, or 50 psi. The variable pressure control valve  10  can be adjusted in the field to achieve the spring pressure rate desired. For example, to set the variable pressure control valve  10  at 45 psi, the compensator device  60  can be adjusted from the position shown in  FIG.  4 A  to a position in which the indication groove  76   a  is flush with the outer surface  82  of the cap  46  to set the spring  26  with a 45-psi compression rating. 
     To set the variable pressure control valve  10  at 48 psi, the compensator device  60  is adjusted by turning the Allen key in the torque transmitting feature  80  clockwise to axially move the compensator device  60  relative to the cap  46  until the indication groove  76   b  is flush with the outer surface  82  of the cap  46  to set the spring  26  with a 48-psi compression rating. 
     To set the variable pressure control valve  10  at 50 psi, the compensator device  60  continues to be adjusted axially about the central axis X until the indication groove  76   c  is flush with the outer surface  82  of the cap  46  to set the spring  26  at a 50-psi compression rating as shown in  FIG.  11   .  FIG.  12    shows the spring  26  at its maximum 50-psi compression rating with the piston  24  in the closed position. When a maximum load (i.e., 50-psi compression rating) is applied on the spring  26 , the head of the compensator device  60  is generally centered within the cap  46 .  FIGS.  4 A and  4 B  show the spring  26  at its minimal 35-psi compression rating. One end of the spring  26  can be contained in the cap  46  while the opposite end of the spring  26  can be contained in the shaft portion  30  of the piston  24 . 
     Teflon™ washers  84  can be positioned at opposing ends  86 ,  88  of the spring  26  to eliminate any friction or torsional influence on the compensator device  60  during operation. The overall length of the spring  26  between the compensator device  60  and the piston  24  or spring cavity  92  can be manipulated as shown in  FIGS.  11  and  12    to achieve a desired pressure rating without any torsional influence. 
     The variable pressure control valve  10  may also include a breather plug  90  that is typically used during defueling operations. For example, the breather plug  90  allows the piston  24  to be blocked so that fuel can flow from the outlet end  16  toward the inlet end  14 . 
       FIGS.  13 - 23    depict another example variable pressure control valve  10   a  in accordance with the principles of the present disclosure. The variable pressure control valve  10   a  has the same features as the variable pressure control valve  10  of  FIGS.  1 - 12    except it includes a two-part valve body. As such, similar reference numbers will be used to describe like elements. 
     Referring to  FIG.  14   , the variable pressure control valve  10   a  includes a first valve housing piece  12   a  and a second housing piece  12   b . The first and second valve housing pieces  12   a ,  12   b  are connected together via fasteners  102 . The first and second valve housing pieces  12   a ,  12   b  can be machined pieces. The valve  10   a  has a more elongate configuration between opposite inlet and outlet ends  14   a ,  16   a  as compared to the valve  10 . Passages  20   a  extend between the inlet and outlet ends  14   a ,  16   a.    
     The variable pressure control valve  10   a  includes a piston  24   a , a spring  26   a , a cap  46   a  that mounts a compensator device  60   a  within the variable pressure control valve  10   a  as depicted in  FIG.  15   . As compared to the compensator device  60 , the compensator device  60   a  has a longer stem  64   a  and the cap  46   a  has a longer extension portion  50   a  to accommodate a larger range of travel of the compensator device  60   a  relative to the cap  46   a . Also, the spring  26   a  is longer than the spring  26 . The variable pressure control valve  10   a  is configured to function similarly to the variable pressure control valve  10  of  FIGS.  1 - 12   . As such, the features of the piston  24   a , the spring  26   a , the cap  46   a  and the compensator device  60   a  will not be repeated for the sake of brevity. 
     The principles, techniques, and features described herein can be applied in a variety of systems, and there is no requirement that all of the advantageous features identified be incorporated in an assembly, system or component to obtain some benefit according to the present disclosure. 
     From the forgoing detailed description, it will be evident that modifications and variations can be made without departing from the spirit and scope of the disclosure.