Fuel system and adjustable pressure regulating valve for regulating a fuel pressure

Abstract

An adjustable pressure regulating valve controls gaseous fuel pressure for a fuel flow in a fuel system. The adjustable pressure regulating valve includes a housing with a spring chamber that houses a plunger spring. The plunger spring biases a pressure sensing plunger extending along the plunger spring to an open position relative to a valve seat. An adjustment mechanism is provided that allows the biasing force of the plunger spring to be externally adjusted without disassembly of the adjustable pressure regulating valve.

Description

Atty Docket No. CMI003-00429 / 24-0823-EBUFUEL SYSTEM AND ADJUSTABLE PRESSURE REGULATING VALVE FOR REGULATING A FUEL PRESSURECross-Reference to Related Application:

[0001] The present application claims priority to, and the benefit of the filing date of, U.S. Provisional Application Ser. No. 63 / 736,740 filed December 20, 2024, which is incorporated herein by reference.Technical field of the disclosure:

[0002] The present disclosure relates generally to fuel systems, and more particularly to an adjustable pressure regulating valve to regulate fuel pressure in a fuel system.BACKGROUND

[0003] Pressure regulating valves are used in fuel systems for prime movers such as internal combustion engines or fuel cells to provide a fuel flow at or below a maximum or desired pressure. Some pressure regulating valves, such as those used in gaseous fuel applications, are required to operate under high working pressures while employing components such as springs, plungers, and seals that control the fuel flow through the pressure regulating valve. These components must be designed and assembled so that the pressure regulating valve properly functions to provide the fuel flow at the regulated pressure for varying the supplied high pressure.

[0004] Differences between various fuel systems and vehicles can make adjustment of the pressure regulating valve desirable. However, disassembly of pressure regulating valves to install new springs, shims, and other adjustment components involves time and cost. In addition, current mechanisms for adjusting pressure regulating valves are not suitable for higher working pressures associated with gaseous fuel systems and do not protect against tampering. Therefore, there remains a need for further improvements in this area.Atty Docket No. CMI003-00429 / 24-0823-EBUDISCLOSURE OF ILLUSTRATIVE EMBODIMENTS

[0005] For the purposes of clearly, concisely and exactly describing illustrative embodiments of the present disclosure, the manner, and process of making and using the same, and to enable the practice, making and use of the same, reference will now be made to certain exemplary embodiments, including those illustrated in the figures, and specific language will be used to describe the same. It shall nevertheless be understood that no limitation of the scope of the invention is thereby created and that the invention includes and protects such alterations, modifications, and further applications of the exemplary embodiments as would occur to one skilled in the art.Atty Docket No. CMI003-00429 / 24-0823-EBUSUMMARY

[0006] The present disclosure includes an adjustable pressure regulating valve for regulating pressure of a fuel flow in a fuel system, including fuel systems that employ gaseous fuel. In an embodiment, an adjustment assembly is provided that adjusts the net force at which at least two plunger springs act upon a pressure sensing plunger that regulates the pressure at which the fuel flows through the pressure regulating valve.

[0007] An embodiment of the present disclosure includes a fuel system for regulating pressure of a fuel flow. The fuel system includes an upstream component for providing a fuel, a downstream component for receiving the fuel, and a pressure regulating valve connecting the upstream component to the downstream component to provide the fuel at a regulated pressure. The pressure regulating valve includes an inlet including an orifice for receiving the fuel from the fuel source. The inlet further includes a valve seat downstream of the orifice. The pressure regulating valve includes a housing including a fuel chamber, and the fuel chamber is fluidly coupled to the orifice downstream of the inlet and to the downstream component. The housing includes a spring chamber. The pressure regulating valve also includes a first spring housed in the spring chamber of the housing and a pressure sensing plunger extending along the first spring. The first spring has a first spring force that biases the pressure sensing plunger away from the valve seat to an open position. The pressure regulating valve further includes an adjustment assembly mounted to the housing. The adjustment assembly includes an adjustment spring having a second spring force acting on the pressure sensing plunger in opposition to the first spring force of the first spring and an adjustment mechanism. The adjustment mechanism is movable relative to the housing to adjust an amount of the second spring force of the adjustment spring acting on the pressure sensing plunger in opposition to the first spring force.

[0008] An embodiment of the present disclosure includes a pressure regulating valve for regulating pressure of a fuel flow. The pressure regulating valve includes a housing including a fuel chamber and a spring chamber. The pressure regulating valve also includes an inlet including an orifice and a valve seat, with the valve seat located between the orifice and the fuel chamber of the housing. The pressure regulating valve includes a first spring housed in the spring chamber of the housing and a pressure sensing plunger extending from the valve seat through the spring chamber to a pressure sensing end. The first spring biases the pressure sensing plunger away from the valve seat to an open position. The pressure regulating valve includes an adjustment springAtty Docket No. CMI003-00429 / 24-0823-EBU having a second spring force acting on the pressure sensing plunger in opposition to the first spring force and an adjustment mechanism mounted to the housing. The adjustment mechanism is configured to adjust an amount of the second spring force of the adjustment spring acting on the pressure sensing plunger in opposition to the first spring force of the first spring.

[0009] This summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used as an aid in limiting the scope of the claimed subject matter. Further embodiments, forms, objects, features, advantages, aspects, and benefits shall become apparent from the following description and drawings.Atty Docket No. CMI003-00429 / 24-0823-EBUBRIEF DESCRIPTION OF THE DRAWINGS

[0010] The description herein makes reference to the accompanying drawings wherein like numerals refer to like parts throughout the several views, and wherein:

[0011] FIG. 1 is a schematic view of a fuel system such as for a prime mover, the fuel system including an adjustable pressure regulating valve according to the present disclosure.

[0012] FIG. 2 is a perspective view of an embodiment of an adjustable pressure regulating valve of the fuel system of FIG. 1.

[0013] FIG. 3 is a longitudinal section view of an example embodiment of the adjustable pressure regulating valve of FIG. 2.

[0014] FIG. 4 is an elevation view of an adjustment assembly of the adjustable pressure regulating valve of FIG. 2.

[0015] FIG. 5 is a perspective view of another embodiment of an adjustable pressure regulating valve of the fuel system of FIG. 1.

[0016] FIG. 6 is a longitudinal section view of the example embodiment of the adjustable pressure regulating valve of FIG. 5.

[0017] FIG. 7 is an elevation view of an adjustment assembly of the adjustable pressure regulating valve of FIG. 5.Atty Docket No. CMI003-00429 / 24-0823-EBUDETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

[0018] With reference to FIG. 1, there is illustrated a fuel system 10 including at least one adjustable pressure regulating valve 100 for regulating a fuel pressure of a flow of a fuel to a prime mover 12, such as a fuel cell or an internal combustion engine. Fuel system 10 may include, for example, a fuel cell, combustion chamber, intake manifold, intake plumbing, compressor, fuel mixer, or any other fuel supply system. The at least one adjustable pressure regulating valve 100 is in fluid communication with an upstream component 16, such as a fuel source containing a fuel 18, and a downstream component 20, such as a fuel rail 24 and / or one or more fuel injectors 22 that provide fuel to the prime mover 12. Pressurized fuel 18 is supplied to adjustable pressure regulating valve 100 from upstream component 16, which outputs the pressurized fuel at a lower, predetermined pressure or pressure range to downstream component 20. Fuel 18 may be, for example, gaseous, fuel such as hydrogen, propane, natural gas, etc. In the discussion that follows, various example embodiments of adjustable pressure regulating valve 100 are shown in FIGs. 2- 4.

[0019] In an embodiment, fuel system 10 is provided for regulating pressure of a fuel flow. Fuel system 10 includes upstream component 16 such as a fuel source for storing fuel 18, downstream component 20 for receiving fuel 18, and adjustable pressure regulating valve 100 connecting upstream component 16 to downstream component 20 to provide fuel 18 at a regulated pressure.

[0020] Referring to FIGs. 2-4, an embodiment of adjustable pressure regulating valve 100 includes an inlet 102 including an orifice 104 for receiving fuel from upstream component 16. Inlet 102 further includes a valve seat 106 downstream of orifice 104. Adjustable pressure regulating valve 100 includes housing 150 including a fuel chamber 152 and a spring chamber 154. Fuel chamber 152 is fluidly coupled to orifice 104 downstream of inlet 102 and to downstream component 20. Adjustable pressure regulating valve 100 also includes at least one first spring or at least one plunger spring 156 housed in spring chamber 154 of housing 150 and a pressure sensing plunger 200 extending along first spring 156. First spring 156 has a first spring force that biases pressure sensing plunger 200 away from valve seat 106 to an open position. Adjustable pressure regulating valve 100 further includes an adjustment assembly 250 mounted to housing 150. Adjustment assembly 250 includes an adjustment spring 252 having a second spring force acting on pressure sensing plunger 200 in opposition to the first spring force of first springAtty Docket No. CMI003-00429 / 24-0823-EBU156 and an adjustment mechanism 254. Adjustment mechanism 254 is movable relative to housing 150 to adjust an amount of the second spring force of adjustment spring 252 acting on pressure sensing plunger 200 in opposition to the first spring force.

[0021] In an embodiment, adjustable pressure regulating valve 100 is provided for regulating pressure of a fuel flow. Adjustable pressure regulating valve 100 includes housing 150 including fuel chamber 152 and spring chamber 154. Adjustable pressure regulating valve 100 also includes inlet 102 including orifice 104 and valve seat 106. Valve seat 106 is located between orifice 104 and fuel chamber 152 of housing 150. Adjustable pressure regulating valve 100 includes first spring 156 housed in spring chamber 154 of housing 150 and pressure sensing plunger 200 extending from valve seat 106 through spring chamber 154 to pressure sensing end 202. First spring 156 biases pressure sensing plunger 200 away from valve seat 106 to an open position. Adjustable pressure regulating valve 100 includes adjustment spring 252 having a second spring force acting on pressure sensing plunger 200 in opposition to the first spring force and adjustment mechanism 254 mounted to housing 150. Adjustment mechanism 254 is configured to adjust an amount of the second spring force of adjustment spring 252 acting on pressure sensing plunger 200 in opposition to the first spring force of first spring 156.

[0022] Further details of an embodiment of adjustable pressure regulating valve 100 are discussed with reference to FIGs. 2-4. Inlet 102 of adjustable pressure regulating valve 100 is sealingly coupled to one side of housing 150, and an outlet 120 is sealingly coupled to a different side of housing 150. In the illustrated embodiment, inlet 102 is connected to a distal side 158 of housing 150, and outlet 120 is connected to a lateral side 160 of housing 150. However, other embodiments contemplated other arrangements, such as inlet 102 and outlet 120 being connected to opposite sides or adjacent lateral sides of housing 150. In yet other embodiments, outlet 120 could be integrated with housing 150 and provided as one piece. Furthermore, when installed, housing 150 can be oriented vertically as shown, or oriented horizontally or obliquely. In the discussion herein, “proximal” or “proximally” refer to an axial location or direction toward a proximal side 162 of housing 150, “distal” or “distally” refers to an axial location or direction toward distal side 158. “Lateral” or “laterally” refers to a direction or location that is transverse to axial direction from distal side 158 to proximal side 162.

[0023] Inlet 102 includes an inlet connector 108 that is configured for connection to a fuel line from upstream component 16. Inlet 102 may also include a sensor port 110 for connection toAtty Docket No. CMI003-00429 / 24-0823-EBU a pressure sensor or other sensor type. As further shown in FIG. 3, inlet 102 includes an inlet flow path 112 and a debris screen 114 in inlet flow path 112 upstream of orifice 104. A spring 116 can be used to maintain debris screen 114 in engagement with inlet 102. Spring 116 can be positioned between debris screen 114 and a plug 118. Plug 118 can be removed to allow removal of debris screen 114 for cleaning or replacement. In an embodiment, plug 118 is replaced by an inlet fitting connection 108 to provide an alternative inlet location connection. In another embodiment, plug 118 could be replaced with inlet connector 108 or other fitting. Other methods for retaining debris screen 114 are also contemplated and not precluded.

[0024] Outlet 120 includes an outlet fitting 122 in fluid communication with an outlet flow path 124. Outlet fitting 122 is connected to a fuel line to provide a pressure regulated flow of fuel from pressure regulating valve 100 to downstream component 20. Outlet 120 may also include a pressure sensor port 126 and a pressure relief valve 130 in fluid communication with outlet flow path 124. A manual bleed port (not shown) could as be added. In other embodiments, any one or more features of outlet 120 could be provided in another flow path of pressure regulating valve 100.

[0025] Pressure relief valve 130 includes a valve body 132 forming a relief chamber 134. Relief chamber 134 houses a relief spring 136, a spring mounting member 138, and a relief plunger 139 biased by relief spring 136 against a relief valve seat 140 of valve body 132. When fuel pressure in outlet flow path 124 exceeds a predetermined threshold pressure, such as a pressure associated with an over-pressure event, the pressure compresses relief spring 136 and displaces relief plunger 139 away from relief valve seat 140. This allows gaseous fuel to enter relief chamber 134 through valve seat 140 and first passage 142 of relief chamber 134. The gaseous fuel in relief chamber 134 is vented through a second passage 144 of spring mounting member 138. Gaseous fuel can then be vented to atmosphere through a relief vent coupled to relief vent fitting 146 mounted to a proximal side of 148 of valve body 132.

[0026] Housing 150 includes fuel chamber 152 that is capable of receiving gaseous fuel from orifice 104 of inlet 102 through valve seat 106 when valve seat 106 is open and providing gaseous fuel to outlet flow path 124 of outlet 120. The pressure of the gaseous fuel flow admitted through valve seat from 106 into fuel chamber 152 is regulated by pressure sensing plunger 200 in pressure chamber 206 in conjunction with plunger spring 156 in spring chamber 154 of housing 150.Atty Docket No. CMI003-00429 / 24-0823-EBU

[0027] Adjustable pressure regulating valve 100 includes adjustment assembly 250 mounted to proximal side 162 of housing 150. In the illustrated embodiment, adjustment assembly 250 includes an end cap 164 attached to proximal side 162 of housing 150. However, other embodiments contemplate all or a portion of end cap 164 is incorporated into housing 150. Adjustment assembly 250 further includes adjustment spring 252 in contact with pressure sensing plunger 200 at or near pressure sensing end 202 in pressure chamber 206. Adjustment spring 252 biases pressure sensing plunger 200 in a distal direction opposite the biasing force of plunger spring 156. Adjustment assembly 250 further includes adjustment mechanism 254 mounted to end cap 164 in contact with adjustment spring 252.

[0028] In the illustrated embodiment, end cap 164 includes an end flange 166 attached to housing 150, and a barrel 168 extending from end flange 166 into housing 150 toward spring chamber 154. Barrel 168 includes an outer surface 170 sealingly engaged to an inner surface 155 of housing 150. Barrel 168 also includes an inner surface 173 that forms a part of and extends around pressure chamber 206. Inner surface 173 forms part of pressure chamber 206 and is offset radially inwardly from the inner surface 155 of housing 150 that forms spring chamber 154. This arrangement decouples pressure chamber 206 from spring chamber 154, allowing flexibility in the sizing of the outer diameter of plunger spring 156 since pressure chamber 206 is separate from spring chamber 154. In addition, the pressure area formed by pressure sensing end 202 and plunger seal 204 that senses the pressure in pressure chamber 206 to displace pressure sensing plunger 200 against the bias of plunger spring 156 is not dependent on the size of spring chamber 154. This allows the plunger spring 156 to be provided with forces and / or spring rates that allow pressure regulating valve 100 to be used in higher pressure applications.

[0029] In the illustrated embodiment, pressure chamber 206 is formed in part by barrel 168 of end cap 164 but could be formed in part by another structure in other embodiments. For example, a separate radial spacer or cylinder could be inserted into and engaged to the inner surface 155 of housing 150 around spring chamber 154 to provide inner surface 173 at proximal end 162 of housing 150. In another embodiment, housing 150 could be formed with a wall or other structure that provides an inner surface 173 that is offset radially inwardly from inner surface 155 that forms spring chamber 154.

[0030] Pressure chamber 206 is enclosed by pressure sensing end 202 of pressure sensing plunger 200 located in barrel 168 of end cap 164, and by plunger seal 204 extending between anAtty Docket No. CMI003-00429 / 24-0823-EBU external surface 210 of pressure sensing end 202 and inner surface 173 of barrel 168. Pressure sensing plunger 200 includes flow channel 208 and inlet holes 212 that allow gaseous fuel in fuel chamber 152 to enter flow channel 208. Flow channel 208 is in fluid communication with pressure chamber 206 through pressure sensing end 202.

[0031] Pressure sensing plunger 200 includes a proximal end portion 214 located in pressure chamber 206 and a flange 216 protruding radially outwardly from proximal end portion 214 at a distal side of barrel 168. Plunger seal 204 is located proximally of flange 216. In addition, a first axial spacer 228 may be located between flange 216 and plunger seal 204.

[0032] Pressure sensing end 202 further includes an opening into cavity 234 defined by proximal end portion 214. Cavity 234 extends into pressure sensing plunger 200 from pressure sensing end 202 in a distal direction along flow channel 208. Adjustment assembly 250 extends through pressure sensing end 202 and into cavity 234 defined by proximal end portion 214 of pressure sensing plunger 200. Adjustment spring 252 of adjustment assembly 250 contacts an internal spring pocket of pressure sensing plunger 200 within cavity 234. The internal spring pocket extends around flow channel 208, and gaseous fuel can flow through cavity 234 to pressure chamber 206.

[0033] Referring further to FIG. 4, an embodiment of adjustment assembly 250 is shown. Adjustment assembly 250 includes adjustment spring 252 that is located entirely within cavity 234 so that adjustment spring 252 is laterally constrained within cavity 234. The proximal end of adjustment spring 252 is in contact with a pressure plate 256 positioned in cavity 234 of pressure sensing plunger 200. Pressure plate 256 receives the adjustment from adjustment mechanism 254 and applies the desired adjustment to adjustment spring 252.

[0034] Pressure plate 256 includes an indent 258 that is complementary shaped with nose 262 of plug 260 of adjustment mechanism 254. In an embodiment, nose 262 is tapered distally to a rounded end. Indent 258 is concave and includes a shape that centers nose 262 on pressure place 256. Adjustment mechanism 254 also includes an adjustment screw 264 and a lock nut 266 coupled to adjustment screw 264. Adjustment screw 264 includes a distal end that contacts plug 260. Adjustment screw 264 is threadable proximally and distally through lock nut 266 and / or end cap 164 to move plug 260 proximally and distally and adjust the biasing force of adjustment spring 252.Atty Docket No. CMI003-00429 / 24-0823-EBU

[0035] End cap 164 includes a bore 268 that receives adjustment mechanism 254. In an embodiment, bore 268 includes a first portion 270 that extends from the exterior of end cap 164 and receives adjustment screw 264. In an embodiment, adjustment screw 264 is threadingly engaged to end cap 164 in first portion 270 of bore 268. Bore 268 includes a second portion 272 extending distally from first portion 270 toward spring chamber 154. Second portion 272 movably receives plug 260. Plug 260 includes a circumferential groove 274 between a proximal flange 276 and a distal flange 278. A plug seal 280 is located in circumferential groove 274 and sealingly engages end cap 164 in second portion 272 of bore 268.

[0036] Adjustment screw 264 and / or lock nut 266 are located on an exterior side of end cap 164 for access to provide manual adjustment of the biasing force of adjustment spring 252 that counteracts the biasing force of plunger spring 156. In the event adjustment screw 264 and / or lock nut 266 are removed from end cap 164 and / or first portion 270 of bore 268, then gaseous fuel is prevented from escaping through bore 268 by plug 260 and plug seal 280 in second portion 272 of bore 268 blocking first portion 270 of bore 268. As a result, adjustment assembly 250 provides a tamper-proof arrangement that prevents fuel leakage in the event adjustment screw 264 is removed. In addition, adjustment screw 264 and / or lock nut 266 can be provided with tamperproof arrangements requiring a special key or tool to manipulate adjustment assembly 250.

[0037] Pressure sensing plunger 200 also includes an intermediate portion 218 extending distally from flange 216, and a distal portion 220 extending distally from intermediate portion 218. In the illustrated embodiment, proximal end portion 214, intermediate portion 218, and distal portion 220 are cylindrical in shape, and / or may include varying diameters and transitions between different diameter portions along all or a part thereof. However, other embodiments contemplate other shapes, such as tapered shapes or non-cylindrical shapes.

[0038] Housing 150 includes guide passage 172 between fuel chamber 152 and spring chamber 154. A part of intermediate portion 218 of pressure sensing plunger 200 is guided in guide passage 172 during movement of pressure sensing plunger 200 toward and away from valve seat 106. Pressure sensing plunger 200 also includes distal portion 220 extending from intermediate portion 218 in guide passage 172. Guide passage 172 can provide a close fit with intermediate portion 218 to guide axial movement of pressure sensing plunger 200 in the proximal and distal directions.Atty Docket No. CMI003-00429 / 24-0823-EBU

[0039] A second plunger seal 222 located in guide passage 172 extends between and sealingly engages distal portion 220 of pressure sensing plunger 200 and an inner surface of housing 150 that extends along guide passage 172. A second axial spacer 230 can be provided in guide passage 172 proximally of second plunger seal 222.

[0040] In an embodiment, the first plunger seal 204 and the second plunger seal 222 are configured to substantially prevent fuel from entering spring chamber 154 from either pressure chamber 206 or from fuel chamber 152. In the event some gaseous fuel does enter spring chamber 154, a vent 190 in a lateral side 192 of housing 150 is provided to vent any accumulated gaseous fuel in spring chamber 154 to atmosphere.

[0041] Housing 150 also includes an internal spring pocket 174 around guide passage 172. Plunger spring 156 sits on spring pocket lip 174 and contacts flange 216 of pressure sensing plunger 200 to bias a distal tip 224 of pressure sensing plunger 200 away from valve seat 106. This allows fuel flow from inlet 102 to pass through orifice 104 and valve seat 106 into fuel chamber 152 for outlet to the downstream components 20 from outlet 120. Flange 216 is configured to contact a distal end of barrel 168 to limit proximal displacement of pressure sensing plunger 200, but other arrangements are contemplated such as flange 216 moving into and out of barrel 168, or arrangements in which barrel 168 is not provided.

[0042] In an embodiment, housing 150 includes an annular cylindrical protrusion 176 projecting proximally from spring pocket 174 into spring chamber 154. Protrusion 176 provides a proximal extension of guide passage 172 for additional guided support of pressure sensing plunger 200. Plunger spring 156 is positioned around annular protrusion 176 and supported on spring pocket 174. Annular protrusion 176 can also center plunger spring 156 in spring chamber 154. Embodiments without annular protrusion 176 are also contemplated.

[0043] The fuel accumulated in fuel chamber 152 enters flow channel 208 through inlet holes 212 of pressure sensing plunger 200 and flows through flow channel 208 to pressure sensing end 202. Pressure sensing end 202 can include at least one groove or recess that fluidly connects flow channel 208 to pressure chamber 206 and allows the fuel to flow into pressure chamber 206. When the fuel pressure in pressure chamber 206 acting on pressure sensing end 202 and first plunger seal 204 overcomes the biasing force of plunger spring 156, distal tip 224 of pressure sensing plunger 200 is moved toward valve seat 106 to reduce or stop the fuel flow into fuel chamber 152, maintaining the fuel pressure at or below a predetermined threshold pressure.Atty Docket No. CMI003-00429 / 24-0823-EBU

[0044] If the biasing force of plunger spring 156 causes distal tip 224 to displace distally toward valve seat 106 at a pressure in pressure chamber 206 that is too high or too low relative to a target pressure, adjustment assembly 250 is used to adjust the net biasing force of plunger spring 156. Adjustment mechanism 254 can be manually manipulated to increase or decrease the biasing force of adjustment spring 252 acting distally on pressure sensing plunger 200, which correspondingly decreases or increases the net biasing force of plunger spring 156 that biases pressure sensing plunger 200 in a proximal direction away from valve seat 106. This allows the biasing force of plunger spring 156 to be adjusted and / or tuned without disassembly of pressure regulating valve 100.

[0045] Referring to FIGs. 5-7, another embodiment of the adjustable pressure regulating valve is shown that is designated as pressure regulating valve 500. Pressure regulating valve 500 functions similarly to pressure regulating valve 100, and can include inlet 502 including orifice 504 for receiving fuel from an upstream component, such as upstream component 16. Inlet 502 further includes valve seat 506 downstream of orifice 504. Adjustable pressure regulating valve 500 includes housing 550 including a fuel chamber 552 and a spring chamber 554. Fuel chamber 552 is fluidly coupled to orifice 504 downstream of inlet 502 and to a downstream component, such as downstream component 20 discussed above.

[0046] Adjustable pressure regulating valve 500 also includes at least one first spring or at least one plunger spring 556 housed in spring chamber 554 of housing 550 and a pressure sensing plunger 600 extending along first spring 556. First spring 556 has a first spring force that biases pressure sensing plunger 600 away from valve seat 506 to an open position. Adjustable pressure regulating valve 500 further includes an adjustment assembly 650 mounted to housing 550. Adjustment assembly 650 includes an adjustment spring 652 having a second spring force acting on pressure sensing plunger 600 in opposition to the first spring force of first spring 556 and an adjustment mechanism 654. Adjustment mechanism 654 is movable relative to housing 550 to adjust an amount of the second spring force of adjustment spring 652 acting on pressure sensing plunger 600 in opposition to the first spring force.

[0047] In an embodiment, adjustable pressure regulating valve 500 is provided for regulating pressure of a fuel flow. Adjustable pressure regulating valve 500 includes housing 550 including fuel chamber 552 and spring chamber 554. Adjustable pressure regulating valve 500 also includes inlet 502 including orifice 504 and valve seat 506. Valve seat 506 is located betweenAtty Docket No. CMI003-00429 / 24-0823-EBU orifice 504 and fuel chamber 552 of housing 550. Adjustable pressure regulating valve 500 includes first spring 556 housed in spring chamber 554 of housing 550 and pressure sensing plunger 600 extending from valve seat 506 through spring chamber 554 to pressure sensing end 602. First spring 556 biases pressure sensing plunger 600 away from valve seat 506 to an open position. Adjustable pressure regulating valve 500 includes adjustment spring 652 having a second spring force acting on pressure sensing plunger 600 in opposition to the first spring force and adjustment mechanism 654 mounted to housing 550. Adjustment mechanism 654 is configured to adjust an amount of the second spring force of adjustment spring 652 acting on pressure sensing plunger 600 in opposition to the first spring force of first spring 556.

[0048] Inlet 502 of adjustable pressure regulating valve 500 is sealingly coupled to one side of housing 550, and an outlet can be sealingly coupled to a different side of housing 550. In the illustrated embodiment, inlet 502 is connected to a distal side 558 of housing 150, and an outlet, such as outlet 120 discussed above, is connected to a lateral side 560 of housing 550. However, other embodiments contemplated other arrangements, such as inlet 502 and an outlet being connected to opposite sides or adjacent lateral sides of housing 550. In yet other embodiments, inlet 502 and or an outlet could be integrated with housing 550 and provided as one piece. Furthermore, when installed, housing 550 can be oriented vertically as shown, or oriented horizontally or obliquely.

[0049] Inlet 502 can include an inlet connector that is configured for connection to a fuel line from an upstream component 16. Inlet 502 may also include a sensor port for connection to a pressure sensor or other sensor type. Inlet 502 includes an inlet flow path 512 and a debris screen 514 in inlet flow path 512 upstream of orifice 504. A plug 518 can be provided that can be removed to allow removal of debris screen 514 for cleaning or replacement. In an embodiment, plug 518 is replaced by an inlet fitting connection to provide an alternative inlet location connection. In another embodiment, plug 518 could be replaced with inlet connector or other fitting. Other methods for retaining debris screen 514 are also contemplated and not precluded.

[0050] Housing 550 includes fuel chamber 552 that is capable of receiving gaseous fuel from orifice 504 of inlet 502 through valve seat 506 when valve seat 506 is open and providing gaseous fuel to the outlet. The pressure of the gaseous fuel flow admitted through valve seat from 506 into fuel chamber 552 is regulated by pressure sensing plunger 600 in pressure chamber 606 in conjunction with plunger spring 556 in spring chamber 554 of housing 550.Atty Docket No. CMI003-00429 / 24-0823-EBU

[0051] Adjustable pressure regulating valve 500 includes adjustment assembly 650 mounted to proximal side 562 of housing 550. In the illustrated embodiment, adjustment assembly 650 includes an end cap 564 attached to proximal side 562 of housing 550. However, other embodiments contemplate all or a portion of end cap 564 is incorporated into housing 550. Adjustment assembly 650 further includes adjustment spring 652 in contact with pressure sensing plunger 600 at or near pressure sensing end 602 in pressure chamber 606. Adjustment spring 652 biases pressure sensing plunger 600 in a distal direction opposite the biasing force of plunger spring 556. Adjustment assembly 650 further includes adjustment mechanism 654 mounted to end cap 564 in contact with adjustment spring 652.

[0052] In the illustrated embodiment, end cap 564 includes an end flange 566 attached to housing 550, and a barrel 568 extending from end flange 566 into housing 550 toward spring chamber 554. Barrel 568 includes an outer surface 569 sealingly engaged to an inner surface 555 of housing 550. Barrel 568 also includes an inner surface 573 that forms a part of and extends around pressure chamber 606. The inner surface 573 of barrel 568 forms part of pressure chamber 606 and is offset radially inwardly from the inner surface 555 of housing 550 that forms spring chamber 554. This arrangement decouples pressure chamber 606 from spring chamber 554, allowing flexibility in the sizing of the outer diameter of plunger spring 556 since pressure chamber 606 is separate from spring chamber 554. In addition, the pressure area formed by pressure sensing end 602 and plunger seal 604 that senses the pressure in pressure chamber 606 to displace pressure sensing plunger 600 against the bias of plunger spring 556 is not dependent on the size of spring chamber 554. This allows the plunger spring 556 to be provided with forces and / or spring rates that allow pressure regulating valve 500 to be used in higher pressure applications.

[0053] In the illustrated embodiment, pressure chamber 606 is formed in part by barrel 568 of end cap 564 but could be formed in part by another structure in other embodiments. For example, a separate radial spacer or cylinder could be inserted into and engaged to the inner surface 555 of housing 550 around spring chamber 554 to provide a radially inwardly offset inner surface around pressure chamber 606 at proximal end 562 of housing 550. In another embodiment, housing 550 could be formed with a wall or other structure that provides an inner surface around pressure chamber 606 that is offset radially inwardly from inner surface 555 that forms spring chamber 554.Atty Docket No. CMI003-00429 / 24-0823-EBU

[0054] Pressure chamber 606 is enclosed by pressure sensing end 602 of pressure sensing plunger 600 located in barrel 568 of end cap 564, and by plunger seal 604 extending between an external surface of pressure sensing end 602 and the inner surface of barrel 568. Pressure sensing plunger 600 includes flow channel 608 and inlet holes 612 that allow gaseous fuel in fuel chamber 552 to enter flow channel 608. Flow channel 608 is in fluid communication with pressure chamber 606 through pressure sensing end 602. Pressure sensing plunger 600 includes a proximal end portion 614 located in pressure chamber 606 and a flange 616 protruding radially outwardly from proximal end portion 614 at a distal side of barrel 568. Plunger seal 604 is located proximally of flange 616.

[0055] Pressure sensing end 602 further includes an opening into cavity 634 defined by proximal end portion 614. Cavity 634 extends into pressure sensing plunger 600 from pressure sensing end 602 in a distal direction along flow channel 608. Adjustment assembly 650 extends through pressure sensing end 602 and into cavity 634 defined by proximal end portion 614 of pressure sensing plunger 200. Adjustment spring 652 of adjustment assembly 650 contacts an internal spring pocket of pressure sensing plunger 600 within cavity 634. The internal spring pocket extends around flow channel 608, and gaseous fuel can flow through cavity 634 to pressure chamber 606.

[0056] Adjustment assembly 650 includes adjustment spring 652 that is located entirely within cavity 634 so that adjustment spring 652 is laterally constrained within cavity 634. The proximal end of adjustment spring 652 is in contact with a pressure plate 656 of plug 660 positioned in cavity 634 of pressure sensing plunger 600. Pressure plate 656 receives the adjustment from adjustment mechanism 654 and applies the desired adjustment to adjustment spring 652.

[0057] Pressure plate 656 is integrally formed with a stem 658 of plug 660 of adjustment mechanism 654. In an embodiment, pressure plate 656 includes an inset nose 662 that is located within adjustment spring 652, and pressure plate 656 includes an outer rim that sits on adjustment spring 652. Adjustment mechanism 654 also includes an adjustment screw 664 and a lock nut 666 coupled to adjustment screw 664. Adjustment screw 664 includes a distal end that contacts plug 660. Adjustment screw 664 is threadable proximally and distally through lock nut 666 and / or end cap 564 to move plug 660 proximally and distally and adjust the biasing force of adjustment spring 652.Atty Docket No. CMI003-00429 / 24-0823-EBU

[0058] End cap 564 includes a bore 668 that receives adjustment mechanism 654. In an embodiment, bore 668 includes a first portion 670 that extends from the exterior of end cap 564 and receives adjustment screw 664. In an embodiment, adjustment screw 664 is threadingly engaged to end cap 564 in first portion 670 of bore 668. Bore 668 includes a second portion 672 extending distally from first portion 670 toward spring chamber 554. Second portion 672 movably receives plug 660. A plug seal 680 is located around stem 658 and sealingly engages end cap 564 in second portion 672 of bore 668.

[0059] Adjustment screw 664 and / or lock nut 666 are located on an exterior side of end cap 564 for access to provide manual adjustment of the biasing force of adjustment spring 652 that counteracts the biasing force of plunger spring 556. In the event adjustment screw 664 and / or lock nut 666 are removed from end cap 564 and / or first portion 670 of bore 668, then gaseous fuel is prevented from escaping through bore 668 by plug 660 and plug seal 680 in second portion 672 of bore 668 blocking first portion 670 of bore 668. As a result, adjustment assembly 650 provides a tamper-proof arrangement that prevents fuel leakage in the event adjustment screw 664 is removed. In addition, adjustment screw 664 and / or lock nut 666 can be provided with tamperproof arrangements requiring a special key or tool to manipulate adjustment assembly 650.

[0060] Pressure sensing plunger 600 also includes an intermediate portion 618 extending distally from flange 616, and a distal portion 620 extending distally from intermediate portion 618. In the illustrated embodiment, proximal end portion 614, intermediate portion 618, and distal portion 620 are cylindrical in shape, and / or may include varying diameters and transitions between different diameter portions along all or a part thereof. However, other embodiments contemplate other shapes, such as tapered shapes or non-cylindrical shapes.

[0061] Housing 550 includes guide passage 572 between fuel chamber 552 and spring chamber 554. A part of intermediate portion 618 of pressure sensing plunger 600 is guided in guide passage 572 during movement of pressure sensing plunger 600 toward and away from valve seat 506. Pressure sensing plunger 600 also includes distal portion 620 extending from intermediate portion 618 in guide passage 572. Guide passage 572 can provide a close fit with intermediate portion 618 to guide axial movement of pressure sensing plunger 600 in the proximal and distal directions.

[0062] A second plunger seal 622 located in guide passage 572 extends between and sealingly engages distal portion 620 of pressure sensing plunger 600 and an inner surface ofAtty Docket No. CMI003-00429 / 24-0823-EBU housing 550 that extends along guide passage 572. In an embodiment, the first plunger seal 604 and the second plunger seal 622 are configured to substantially prevent fuel from entering spring chamber 554 from either pressure chamber 606 or from fuel chamber 552. In the event some gaseous fuel does enter spring chamber 554, a vent 590 in a lateral side 592 of housing 550 is provided to vent any accumulated gaseous fuel in spring chamber 554 to atmosphere.

[0063] Similar to housing 150, housing 550 also includes an internal spring pocket 574 around guide passage 572. Plunger spring 556 sits on the spring pocket 574 and contacts flange 616 of pressure sensing plunger 600 to bias a distal tip of pressure sensing plunger 600 away from valve seat 506. This allows fuel flow from inlet 502 to pass through orifice 504 and valve seat 506 into fuel chamber 552 for outlet to the downstream components from the outlet. Flange 616 is configured to contact a distal end of barrel 568 to limit proximal displacement of pressure sensing plunger 600, but other arrangements are contemplated such as flange 616 moving into and out of barrel 568, or arrangements in which barrel 568 is not provided.

[0064] In an embodiment, housing 550 includes an annular cylindrical protrusion 576 projecting proximally from spring pocket 574 into spring chamber 554. Protrusion 576 provides proximal extension of guide passage 572 for additional guided support of pressure sensing plunger 600. Plunger spring 556 is positioned around annular protrusion 576 and supported on the spring pocket. Annular protrusion 576 can also center plunger spring 556 in spring chamber 554. Embodiments without annular protrusion 576 are also contemplated.

[0065] The fuel accumulated in fuel chamber 552 enters flow channel 608 through inlet holes 612 of pressure sensing plunger 600 and flows through flow channel 608 to pressure sensing end 602. Pressure sensing end 602 can include at least one groove or recess that fluidly connects flow channel 608 to pressure chamber 606 and allows the fuel to flow into pressure chamber 606. When the fuel pressure in pressure chamber 606 acting on pressure sensing end 602 and first plunger seal 604 overcomes the biasing force of plunger spring 556, distal tip 624 of pressure sensing plunger 600 is moved toward valve seat 506 to reduce or stop the fuel flow into fuel chamber 552, maintaining the fuel pressure at or below a predetermined threshold pressure.

[0066] If the biasing force of plunger spring 556 causes distal tip 624 to displace distally toward valve seat 506 at a pressure in pressure chamber 606 that is too high or too low relative to a target pressure, adjustment assembly 650 is used to adjust the net biasing force of plunger spring 556. Adjustment mechanism 654 can be manually manipulated to increase or decrease the biasingAtty Docket No. CMI003-00429 / 24-0823-EBU force of adjustment spring 652 acting distally on pressure sensing plunger 600, which correspondingly decreases or increases the net biasing force of plunger spring 556 that biases pressure sensing plunger 600 in a proximal direction away from valve seat 506. This allows the biasing force of plunger spring 556 to be adjusted and / or tuned without disassembly of pressure regulating valve 500.

[0067] Further written description of a number of example embodiments shall now be provided. In an example embodiment, a fuel system for regulating pressure for a fuel flow is provided. The fuel system includes an upstream component for providing a fuel, a downstream component for receiving the fuel, and a pressure regulating valve connecting the upstream component to the downstream component to provide the fuel at a regulated pressure. The pressure regulating valve includes an inlet including an orifice for receiving the fuel from the fuel source. The inlet further includes a valve seat downstream of the orifice. The pressure regulating valve includes a housing including a fuel chamber, and the fuel chamber is fluidly coupled to the orifice downstream of the inlet and to the downstream component. The housing includes a spring chamber. The pressure regulating valve also includes a first spring housed in the spring chamber of the housing and a pressure sensing plunger extending along the first spring. The first spring has a first spring force that biases the pressure sensing plunger away from the valve seat to an open position. The pressure regulating valve further includes an adjustment assembly mounted to the housing. The adjustment assembly includes an adjustment spring having a second spring force acting on the pressure sensing plunger in opposition to the first spring force of the first spring and an adjustment mechanism. The adjustment mechanism is movable relative to the housing to adjust an amount of the second spring force of the adjustment spring acting on the pressure sensing plunger in opposition to the first spring force.

[0068] In an embodiment, the pressure sensing plunger includes a pressure sensing end and a plunger seal around the pressure sensing end. The pressure sensing end and the plunger seal are positioned in a pressure chamber of the pressure regulating valve. The adjustment assembly extends through the pressure chamber and the pressure sensing end of the pressure sensing plunger into contact the pressure sensing plunger.

[0069] In an embodiment, the pressure sensing plunger includes a cavity in the pressure sensing end. The adjustment spring extends through the cavity to contact the pressure sensing plunger.Atty Docket No. CMI003-00429 / 24-0823-EBU

[0070] In an embodiment, the pressure sensing plunger includes a flow channel that opens into the cavity. The pressure sensing plunger fluidly connects the fuel chamber of the housing with the pressure chamber. A pressure of the fuel in the pressure chamber acts on the pressure sensing end of the pressure sensing plunger and the plunger seal to seat the pressure sensing plunger on the valve seat when the pressure of the fuel in the pressure chamber and the second spring force are greater than the first spring force.

[0071] In an embodiment, the adjustment assembly includes an end cap mounted to the housing. The end cap encloses the spring chamber and the adjustment mechanism is mounted to and extends through the end cap.

[0072] In an embodiment, the end cap includes a bore that receives the adjustment mechanism. The adjustment mechanism is engaged to the end cap in the bore, and extends through the bore to be accessible on an exterior of the end cap.

[0073] In an embodiment, the bore of the end cap includes a first portion extending from the exterior of the end cap into the end cap and a second portion extending from the first portion toward the spring chamber. The adjustment mechanism includes an adjustment screw threadingly engaged to the end cap in the first portion of the bore, and a plug movably positioned in the second portion of the bore.

[0074] In an embodiment, a pressure relief valve is connected between the housing and the downstream component.

[0075] In an embodiment, the inlet includes a debris screen upstream of the orifice.

[0076] In an embodiment, the first spring extends between and contacts the housing and the pressure sensing plunger. The adjustment spring extends between and contacts the pressure sensing plunger and the adjustment mechanism.

[0077] According to another example embodiment of the present disclosure, a pressure regulating valve for regulating pressure for a fuel flow is provided. The pressure regulating valve includes a housing including a fuel chamber and a spring chamber. The pressure regulating valve also includes an inlet including an orifice and a valve seat, with the valve seat located between the orifice and the fuel chamber of the housing. The pressure regulating valve includes a first spring housed in the spring chamber of the housing and a pressure sensing plunger extending from the valve seat through the spring chamber to a pressure sensing end. The first spring biases the pressure sensing plunger away from the valve seat to an open position. The pressure regulatingAtty Docket No. CMI003-00429 / 24-0823-EBU valve includes an adjustment spring having a second spring force acting on the pressure sensing plunger in opposition to the first spring force and an adjustment mechanism mounted to the housing. The adjustment mechanism is configured to adjust an amount of the second spring force of the adjustment spring acting on the pressure sensing plunger in opposition to the first spring force of the first spring.

[0078] In an embodiment, the pressure sensing plunger includes a cavity extending into the pressure sensing end. The adjustment spring is positioned in the cavity in contact with the pressure sensing plunger.

[0079] In an embodiment, the pressure regulating valve includes an end cap mounted to the housing adjacent the pressure sensing end of the plunger. The adjustment mechanism is coupled to the end cap.

[0080] In an embodiment, the adjustment mechanism includes an adjustment screw extending through the end cap. The adjustment screw is operable to adjust the amount of the second spring force.

[0081] In an embodiment, the adjustment mechanism includes a plug movably positioned within a bore of the end cap between the adjustment screw and the adjustment spring. A seal is positioned in the bore between the plug and the end cap.

[0082] In an embodiment, the adjustment mechanism includes a pressure plate between the plug and the adjustment spring. The pressure plate is supported on the adjustment spring and the plug contacts the pressure plate.

[0083] In an embodiment, the plug includes a distal end nose that projects from the end cap to contact the pressure plate to force the pressure plate against the adjustment spring.

[0084] In an embodiment, the plug includes a circumferential groove and the seal is positioned in the circumferential groove of the plug.

[0085] In an embodiment, the adjustment mechanism includes a lock nut threadingly engaged to an adjustment screw. The lock nut is located on an exterior of the housing, and the adjustment screw is operable to displace the second spring acting on the pressure sensing plunger adjust the amount of the second spring force.

[0086] In an embodiment, the adjustment mechanism includes a plug that is positioned in a bore that extends through the housing. The plug includes a seal that seals the bore to prevent gas from passing through the bore to an exterior of the housing.Atty Docket No. CMI003-00429 / 24-0823-EBU

[0087] While illustrative embodiments of the disclosure have been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that only certain exemplary embodiments have been shown and described and that all changes and modifications that come within the spirit of the claimed inventions are desired to be protected. It should be understood that while the use of words such as preferable, preferably, preferred or more preferred utilized in the description above indicates that the feature so described may be more desirable, it nonetheless may not be necessary and embodiments lacking the same may be contemplated as within the scope of the invention, the scope being defined by the claims that follow. In reading the claims, it is intended that when words such as “a,” “an,” “at least one,” or “at least one portion” are used there is no intention to limit the claim to only one item unless specifically stated to the contrary in the claim. When the language “at least a portion” and / or “a portion” is used the item can include a portion and / or the entire item unless specifically stated to the contrary.

Claims

Atty Docket No. CMI003-00429 / 24-0823-EBUWHAT TS CLAIMED IS:

1. A fuel system for regulating pressure for a fuel flow, the fuel system comprising: an upstream component for providing a fuel; a downstream component for receiving the fuel; and a pressure regulating valve connecting the upstream component to the downstream component to output the fuel from the upstream component to the downstream component at a regulated pressure, the pressure regulating valve including: an inlet including an orifice for receiving the fuel from the fuel source, the inlet further including a valve seat downstream of the orifice; a housing including a fuel chamber, the fuel chamber fluidly coupled to the orifice downstream of the inlet and to the downstream component, the housing including a spring chamber; a first spring housed in the spring chamber of the housing; a pressure sensing plunger extending along the first spring, the first spring having a first spring force that biases the pressure sensing plunger away from the valve seat to an open position; and an adjustment assembly mounted to the housing, the adjustment assembly including: an adjustment spring having a second spring force acting on the pressure sensing plunger in opposition to the first spring force of the first spring; and an adjustment mechanism movable relative to the housing to adjust an amount of the second spring force of the adjustment spring acting on the pressure plunger in opposition to the first spring force.

2. The fuel system according to claim 1, wherein: the pressure sensing plunger includes a pressure sensing end and a plunger seal around the pressure sensing end, the pressure sensing end and the plunger seal positioned in a pressure chamber of the pressure regulating valve; and the adjustment assembly extends through the pressure chamber and the pressure sensing end of the pressure sensing plunger into contact the pressure sensing plunger.Atty Docket No. CMI003-00429 / 24-0823-EBU3. The fuel system according to claim 2, wherein: the pressure sensing plunger includes a cavity in the pressure sensing end; and the adjustment spring extends through the cavity to contact the pressure sensing plunger.

4. The fuel system according to claim 3, wherein: the pressure sensing plunger includes a flow channel that opens into the cavity, the pressure sensing plunger fluidly connecting the fuel chamber of the housing with the pressure chamber; and a pressure of the fuel in the pressure chamber acts on the pressure sensing end of the pressure sensing plunger and the plunger seal to seat the pressure sensing plunger on the valve seat when the pressure of the fuel in the pressure chamber and the second spring force are greater than the first spring force.

5. The fuel system according to claim 1, wherein the adjustment assembly includes: an end cap mounted to the housing, the end cap enclosing the spring chamber; and the adjustment mechanism is mounted to and extends through the end cap.

6. The fuel system according to claim 5, wherein: the end cap includes a bore that receives the adjustment mechanism; and the adjustment mechanism is engaged to the end cap in the bore, and extends through the bore to be accessible on an exterior of the end cap.

7. The fuel system according to claim 6, wherein: the bore of the end cap includes: a first portion extending from the exterior of the end cap into the end cap; and a second portion extending from the first portion toward the spring chamber; the adjustment mechanism includes: an adjustment screw threadingly engaged to the end cap in the first portion of the bore; and a plug movably positioned in the second portion of the bore.Atty Docket No. CMI003-00429 / 24-0823-EBU8. The fuel system according to claim 1 , further comprising a pressure relief valve connected between the housing and the downstream component.

9. The fuel system according to claim 1, wherein the inlet includes a debris screen upstream of the orifice.

10. The fuel system according to claim 1, wherein: the first spring extends between and contacts the housing and the pressure sensing plunger; and the adjustment spring extends between and contacts the pressure sensing plunger and the adjustment mechanism.

11. A pressure regulating valve for regulating pressure for a fuel flow, the pressure regulating valve including: a housing including a fuel chamber and a spring chamber; an inlet including an orifice and a valve seat, the valve seat located between the orifice and the fuel chamber of the housing; a first spring housed in the spring chamber of the housing; a pressure sensing plunger extending from the valve seat through the spring chamber to a pressure sensing end, the first spring biasing the pressure sensing plunger away from the valve seat to an open position; an adjustment spring having a second spring force acting on the pressure sensing plunger in opposition to the first spring force; and an adjustment mechanism mounted to the housing, the adjustment mechanism configured to adjust an amount of the second spring force of the adjustment spring acting on the pressure sensing plunger in opposition to the first spring force of the first spring.

12. The pressure regulating valve according to claim 11, wherein: the pressure sensing plunger includes a cavity extending into the pressure sensing end; and the adjustment spring is positioned in the cavity in contact with the pressure sensing plunger.Atty Docket No. CMI003-00429 / 24-0823-EBU13. The pressure regulating valve according to claim 11, further comprising: an end cap mounted to the housing adjacent the pressure sensing end of the plunger; and the adjustment mechanism is coupled to the end cap.

14. The pressure regulating valve according to claim 13, wherein the adjustment mechanism includes an adjustment screw extending through the end cap, the adjustment screw being operable to adjust the amount of the second spring force.

15. The pressure regulating valve according to claim 13, wherein the adjustment mechanism includes: a plug movably positioned within a bore of the end cap between the adjustment screw and the adjustment spring; and a seal in the bore between the plug and the end cap.

16. The pressure regulating valve according to claim 15, wherein: the adjustment mechanism includes a pressure plate between the plug and the adjustment spring; and the pressure plate is supported on the adjustment spring and the plug contacts the pressure plate.

17. The pressure regulating valve according to claim 16, wherein the plug includes a distal end nose that projects from the end cap to contact the pressure plate to force the pressure plate against the adjustment spring.

18. The pressure regulating valve according to claim 15, wherein the plug includes a circumferential groove and the seal is positioned in the circumferential groove of the plug.

19. The pressure regulating valve according to claim 11, wherein: the adjustment mechanism includes a lock nut threadingly engaged to an adjustment screw; the lock nut is located on an exterior of the housing; andAtty Docket No. CMI003-00429 / 24-0823-EBU the adjustment screw is operable to displace the second spring acting on the pressure sensing plunger adjust the amount of the second spring force.

20. The pressure regulating valve according to claim 11, wherein: the adjustment mechanism includes a plug that is positioned in a bore that extends through the housing; and the plug including a seal that seals the bore to prevent gas from passing through the bore to an exterior of the housing.

Images