WO2024163727A1

WO2024163727A1 - Adjustable pressure-independent control valves

Info

Publication number: WO2024163727A1
Application number: PCT/US2024/013978
Authority: WO
Inventors: Sean R. AMARAL; Viral DHARAIYA
Original assignee: Romac Industries, Inc.
Priority date: 2023-02-03
Filing date: 2024-02-01
Publication date: 2024-08-08

Abstract

An adjustable pressure-independent fluid flow control valve comprises a housing defining a fluid flow passage extending therethrough, the housing having openings for flow into and out of the fluid flow passage, an orifice disposed in the fluid flow passage of the housing, the orifice having a seat at an end thereof, and an elastomeric diaphragm disposed in the fluid flow passage of the housing, the diaphragm having a surface that is urged against the seat of the orifice by fluid flow through the valve such that a flow rate of fluid through the valve is constant as upstream pressure changes, wherein the orifice can be moved with respect to the diaphragm to adjust the flow rate of the fluid through the valve.

Description

ADJUSTABLE PRESSURE-INDEPENDENT CONTROL VALVES

BACKGROUND

Technical Field

Embodiments relate generally to adjustable fluid flow control valves (also referred to as adjustable balancing valves or pressure-independent control valves) and more particularly to fluid flow control valves having orifices defining a seat against which an elastomeric diaphragm is urged by pressure of the fluid.

Description of the Related Art

Fluid flow control valves of the above-described type are particularly used for regulating fluid flow to a substantially constant flow rate (e.g., a volume flow per unit time, such as gallons per minute) over a range of upstream fluid pressures, such as about 0.1 bar to 10 bars. In such valves, the diaphragm typically comprises a solid body of elastomeric material. When urged against the seat of the orifice, the diaphragm deforms, the degree of deformation increasing with increasing pressure differential across the diaphragm. As the deformation of the diaphragm increases, flow control passages between the diaphragm and the seat become smaller. The valve is designed such that over the range of pressure differentials of interest, the changing flow area of the flow control passages offsets the changing pressure differential so as to maintain a substantially constant flow rate.

The flow rate through the flow control passages is proportional to the flow area of the passages multiplied by the square root of the pressure. Accordingly, the flow area of the flow control passages must change significantly from the lowest working pressure to the highest working pressure (e.g., from 0.1 bar to 10 bars) in order to maintain a substantially constant flow rate at all pressures. Various approaches have been taken to try to tailor the deflection of the diaphragm against the orifice seat to maintain a substantially constant flow rate over the full pressure differential range.

BRIEF SUMMARY

Some embodiments provide a fluid flow control valve comprising a housing defining a fluid flow passage extending therethrough, the housing having opposite ends each defining an opening for flow into and out of the fluid flow passage, and an orifice and diaphragm disposed in the housing. The orifice has a seat. The diaphragm has one end face that opposes the seat of the orifice, the seat being configured such that one or more flow control passages are defined between the seat and the one end face of the diaphragm through which the fluid flows. In some embodiments, the seat is contoured to include at least two different shapes of channels each promoting localized bending of the diaphragm at a different pressure differential, thereby permitting an expansion of the working pressure range to very low pressure differentials.

In some embodiments, the seat of the orifice has a main support surface defining a plurality of channels therein including at least one relatively wide channel promoting localized bending of the diaphragm thereinto at a relatively low pressure differential range, and at least one relatively narrow channel promoting localized bending of the diaphragm thereinto at a relatively higher pressure differential range, each channel extending in a transverse direction of the orifice and the channels being circumferentially spaced from each other.

The channels may have a V-shaped cross section normal to the transverse direction. The walls defining the channel can be planar or non-planar. One or more of the channels can include a longitudinal slot formed at the bottom of the channel. The slot may be engaged by and begin to be constricted by the diaphragm after the channel has been completely closed off by the diaphragm. The slot thus functions as a third type of channel regulating flow rate at a third range of pressure differentials higher than that of the wide and narrow converging channels.

In some embodiments, the orifice includes a plurality of spaced protrusions that extend beyond the main support surface in the direction toward the diaphragm. The protrusions engage the diaphragm and hold it off the main support surface at low pressure differentials. The protrusions may be sized in contact area and are spaced in relation to the diaphragm to promote bending of the diaphragm between the protrusions. Between each two adjacent protrusions there may be at least one of the channels. Thus, at low pressure differentials, the diaphragm bends between the protrusions, eventually coming into contact with the main support surface on either side of the channel(s) as the pressure differential increases to a predetermined magnitude. Further increases in the pressure differential then cause the diaphragm to bend into the channel(s). Each channel will be completely closed off by the diaphragm when the pressure differential becomes large enough, the wide channels becoming closed at a lower pressure differential than the narrow channels. The diaphragm may have sufficient rigidity, through careful selection of its length-to-diameter ratio and durometer hardness, to permit the localized bending of the diaphragm into the channels while substantially reducing the creep of the diaphragm over time. An adjustable pressure-independent fluid flow control valve may be summarized as comprising: a housing defining a fluid flow passage extending therethrough, the housing having openings for flow into and out of the fluid flow passage; an orifice disposed in the fluid flow passage of the housing, the orifice having a seat at an end thereof; and an elastomeric diaphragm disposed in the fluid flow passage of the housing, the diaphragm having a surface that is urged against the seat of the orifice by fluid flow through the valve such that a flow rate of fluid through the valve is constant as upstream pressure changes; wherein the orifice can be moved with respect to the diaphragm to adjust the flow rate of the fluid through the valve.

The adjustable pressure-independent fluid flow control valve may include no coil springs. The valve may be configured to be manually actuated or electrically actuated to move the orifice with respect to the diaphragm. The adjustable pressure-independent fluid control valve may further comprise a cartridge, wherein the orifice is held in position by the cartridge. The orifice may include grooves and the cartridge may include rails seated within the grooves. The orifice may be movable linearly with respect to the diaphragm along the rails to adjust the flow rate of the fluid through the valve.

An adjustable pressure-independent fluid flow control valve may be summarized as comprising: a housing defining a fluid flow passage extending therethrough, the housing having openings for flow into and out of the fluid flow passage; an orifice disposed in the fluid flow passage of the housing, the orifice having a seat at an end thereof, the orifice having a shape generally comprising a rectangular prism; and an elastomeric diaphragm disposed in the fluid flow passage of the housing, the diaphragm having a shape generally comprising a rectangular prism, the diaphragm having a surface that is urged against the seat of the orifice by fluid flow through the valve such that a flow rate of fluid through the valve is constant as upstream pressure changes. The orifice may be movable with respect to the diaphragm to adjust the flow rate of the fluid through the valve.

An adjustable pressure-independent fluid flow control valve may be summarized as comprising: a housing defining a fluid flow passage extending therethrough, the housing having openings for flow into and out of the fluid flow passage; an orifice disposed in the fluid flow passage of the housing, the orifice having a first seat at a first end thereof and a second seat at a second end thereof, the second end opposite to the first end; a first elastomeric diaphragm disposed in the fluid flow passage of the housing; and a second elastomeric diaphragm disposed in the fluid flow passage of the housing; wherein the first diaphragm has a first surface that is urged against the first seat of the orifice by fluid flow through the valve and the second diaphragm has a second surface that is urged against the second seat of the orifice by fluid flow through the valve such that a flow rate of fluid through the valve is constant as upstream pressure changes. The orifice may be movable with respect to the diaphragms to adjust the flow rate of the fluid through the valve. The orifice may have a shape generally comprising a rectangular prism and the first and second diaphragms may each have a shape generally comprising a rectangular prism.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

Figure 1 illustrates an exploded perspective view of an orifice and a diaphragm of the prior art.

Figure 2 illustrates an exploded perspective view of a fluid flow control valve of the prior art.

Figure 3 illustrates a cross-sectional view of an assembled valve of the prior art along a plane through a longitudinal centerline of the valve.

Figure 4 illustrates a perspective view of a manually-operated pressure-independent control valve.

Figure 5 illustrates another perspective view of the manually-operated pressureindependent control valve of Figure 4.

Figure 6 illustrates a cross-sectional view of components of the manually-operated pressure-independent control valve of Figures 4 and 5.

Figure 7 illustrates a perspective view of internal components of the manually-operated pressure-independent control valve of Figures 4 and 5.

Figure 8 illustrates a perspective view of internal components of the manually-operated pressure-independent control valve of Figures 4 and 5.

Figure 9 illustrates a perspective view of internal components of the manually-operated pressure-independent control valve of Figures 4 and 5.

Figure 10 illustrates a perspective view of an electrically-operated pressure-independent control valve.

Figure 11 illustrates a perspective view of components of the electrically-operated pressure-independent control valve of Figure 10.

Figure 12 illustrates a perspective view of an orifice for use in the pressure independent control valves of Figures 4 and 10.

Figure 13 illustrates another perspective view of the orifice of Figure 12. Figure 14 illustrates an end view of the orifice of Figure 12.

DETAILED DESCRIPTION

In the following description, certain specific details are set forth in order to provide a thorough understanding of various disclosed implementations. However, one skilled in the relevant art will recognize that implementations may be practiced without one or more of these specific details, or with other methods, components, materials, etc. In other instances, well- known structures associated with the technology have not been shown or described in detail to avoid unnecessarily obscuring descriptions of the implementations.

Figures 1-3 depict a fluid flow control valve 10 of the prior art, features of which may be included in the embodiments described herein. The valve 10 includes a housing 11 formed by an inlet housing 12, an outlet housing 14, and a cap nut 16 that is internally threaded and screws onto an externally threaded end of the inlet housing 12 so as to compress the outlet housing 14 against a sealing surface of the inlet housing 12 with a seal 18 disposed therebetween so as to seal the housing. The housing thus forms a generally tubular structure with a longitudinal fluid flow passage extending therethrough from an inlet end defined by the inlet housing 12 to an outlet end defined by the outlet housing 14. Generally, a pressure of the fluid flowing through the fluid flow control valve 10 is higher on an upstream side of the fluid flow control valve 10 (generally at the inlet end thereof) than on a downstream side of the fluid flow control valve 10 (generally at the outlet end thereof). The terms “inlet” and “outlet,” and corresponding terms “upstream” and “downstream” are used herein with reference to a normal forward direction of fluid flow through the valve 10 in which the flow rate is to be controlled in a desired manner. It will be understood, however, that the valve 10 is also capable of passing fluid in a reverse direction, z.e., from the “outlet” end to the “inlet” end.

The inlet housing 12 thus defines an inlet port 20 and the outlet housing 14 defines an outlet port 22 for fluid flow. The inlet and outlet ends of the housing are configured to be attached in any suitable manner to fluid-conducting conduits.

An orifice 24 is disposed within the flow passage of the housing. The orifice 24 includes a generally tubular outer wall or support portion 26 having a diameter slightly less than that of the inner surface of the housing, and having a central flow passage 28 therethrough. A seat 30 is defined by the orifice 24 at an upstream end thereof. The seat 30 is formed on a tubular portion 32 (Figure 2) of the orifice having a smaller diameter than that of the tubular support portion 26 and joined to the tubular support portion concentrically therewith. The orifice 24 in the illustrated embodiment also includes an integral spider 34 having a plurality of legs 36 integrally formed with the tubular support portion 26 of the orifice. The legs 36 are circumferentially spaced from one another and extend from the tubular support portion 26 in the upstream direction beyond the seat 30 of the orifice. Four legs 36 are shown in the illustrated embodiment, spaced 90° apart, but it will be understood that a different number of legs can be used if desired. The legs comprise generally beam-shaped members in the illustrated embodiment, but other shapes can be used instead. Although an integral spider is shown in the drawings, it will be understood that a separate spider or other type of device can be used for holding the diaphragm in its proper position and orientation relative to the orifice.

The valve 10 also includes a diaphragm 40 that acts in conjunction with the orifice 24 to control the rate of fluid flow through the valve in the forward direction. The diaphragm comprises a solid disc-shaped piece of elastomeric material. The outer peripheral surface 42 of the diaphragm is substantially cylindrical and has a diameter sized to allow the diaphragm to fit between the legs 36 of the integral spider and orifice. There is sufficient radial clearance between the diaphragm and the legs to allow the diaphragm to freely move axially in the upstream and downstream directions. The diaphragm 40 has opposite end faces 44 and 46 which may be formed identically to each other, and advantageously formed as planar surfaces. Alternatively, the end faces 44 and 46 could be conical, spherical, or shaped as some other surface of a body of revolution, such that the diaphragm can be rotated about its axis without affecting the interface between the diaphragm and the seat 30 of the orifice. Each of the end faces 44, 46 of the diaphragm can have a flow-straightening cone 48 formed thereon. Thus, if the face against the seat 30 becomes permanently deformed or worn after prolonged use, the diaphragm 40 can be reversed so that the other face is against the seat, thus extending the useful life of the diaphragm.

Forward fluid flow through the valve 10 causes the diaphragm 40 to be moved against the seat 30 of the orifice. The legs 36 of the integral spider align the diaphragm in the radial direction so that the end face 44 of the diaphragm contacts the seat 30 about its entire circumference. The legs 36 also space the diaphragm away from the inner surface of the housing so that a consistent and predictable flow passage exists between the outer peripheral surface 42 of the diaphragm and the inner surface of the housing. The fluid flows through this flow passage, and then is turned by the tubular support portion 26 of the orifice so as to flow radially inwardly and then through flow control passages defined between the end face 44 of the diaphragm and the seat 30, and finally out the central passage 28 of the orifice and out the outlet port 22 of the housing. The seat 30 is contoured to be non-planar and can include, for example, grooves or channels. As the pressure differential across the diaphragm increases, the diaphragm is pressed with greater and greater pressure against the seat 30 and deforms so as to conform to a greater and greater extent with the contour of the seat. Accordingly, the flow passages between the diaphragm and seat become smaller and smaller, which compensates for the increasing pressure differential so as to maintain the flow rate through the valve substantially constant, at least over a limited range of pressure differentials, such as about 0.1 bar to 10 bars.

The valve 10 further includes a diaphragm stop member 52 for limiting the extent to which the diaphragm can move axially away from the seat 30 during reverse flow through the valve. The stop member 52 may comprise a spring element that is seated against a radial shoulder 53 formed on the inlet housing 12 and biases the legs 36 of the orifice toward the outlet housing 14, thereby urging the end face 54 of the orifice against an opposing radial shoulder 55 of the outlet housing 14. A seal 56 is disposed between these surfaces to seal the connection between the orifice and the outlet housing. The end face 54 of the orifice includes a groove 57 for retaining the seal 56. The stop member 52 in the illustrated embodiment is a spring finger washer. Flow passages are defined between the fingers of the washer and between the ring of the washer and the inner surface of the housing for reverse flow of fluid. During forward flow, the central aperture of the washer is not blocked by the diaphragm as it is in reverse flow, and thus the washer presents no substantial flow restriction during forward flow.

The seat 30 of the orifice is contoured to provide at least two different shapes of channels between the diaphragm 40 and the seat, each shape being tailored to regulate flow at a different range of pressure differentials from the other channel shape(s). Moreover, the seat and the diaphragm are designed to promote simple supported beam-like bending of the diaphragm into the channels, as opposed to a local deformation of very small projections into the diaphragm or a complex bending of an annular washer-type diaphragm as in some prior flow control valves. Thus, the deflection of the diaphragm can be predicted with good accuracy, enabling more- accurate control of the sizes of the flow passages at various pressure differentials.

Additional features of the valve 10 are provided in U.S. patent nos. 6,390,122 and 6,311,712, which are hereby incorporated herein by reference in their entireties. Any of the features described therein can be incorporated into the embodiments described herein.

Figures 4 and 5 depict a fluid flow control valve 110 and Figure 6 depicts a cross- sectional view of components thereof. The valve 110 includes a housing 111 formed by a housing base 112 and a housing cap 114, where both of the housing base 112 and the housing cap 114 may be formed from brass, and where the housing cap 114 may be compressed against a sealing surface of the housing base 112, such as with a seal disposed therebetween so as to seal the housing 111. The housing 111 has a longitudinal fluid flow passage extending therethrough from an inlet end defined by an inlet opening (illustrated at top right in Figures 4 and 6 and at top left in Figure 5) to an outlet end defined by an outlet opening (illustrated at bottom left in Figures 4 and 6 and at bottom right in Figure 5). Generally, a pressure of the fluid flowing through the fluid flow control valve 110 is higher on an upstream side of the fluid flow control valve 110 (generally at the inlet end thereof) than on a downstream side of the fluid flow control valve 110 (generally at the outlet end thereof). The terms “inlet” and “outlet,” and corresponding terms “upstream” and “downstream” are used herein with reference to a normal forward direction of fluid flow through the valve 110 in which the flow rate is to be controlled in a desired manner. It will be understood, however, that the valve 110 is also capable of passing fluid in a reverse direction, z.e., from the “outlet” end to the “inlet” end.

The housing base 112 thus defines an inlet port 120 and an outlet port 122 for fluid flow through the valve 110. The inlet and outlet ends of the housing 111 are configured to be attached in any suitable manner to fluid-conducting conduits.

A holder or cartridge 123, an orifice 124, and a pair of diaphragms 140 are disposed within the flow passage of the housing 111. The cartridge 123 may be formed of an injection- molded plastic and may be seated within the cavity or internal space within the housing 111 and remains stationary therein while the valve 110 is in use. For example, frictional forces between the cartridge 123 and the housing 111 may resist or prevent rotation of the cartridge 123 with respect to the housing 111 (similarly, frictional forces between other combinations of components of the valve 110 may resist or prevent relative rotation of such components). The orifice 124 may be formed from the same material as the cartridge 123 and includes a body having a shape generally comprising a rectangular prism, and is held in place by the cartridge 123, as described further elsewhere herein. A pair of seats 130 are defined by the orifice 124 at upstream surfaces thereof, as described further elsewhere herein. The seats 130 are formed on opposing major surfaces of the orifice 124. The diaphragms 140 act in conjunction with the orifice 124 to control the rate of fluid flow through the valve 110 in the forward direction. The diaphragms 140 are made of an elastomeric material such as EPDM rubber and have a Shore A durometer hardness from about 55 to about 69, or about 63. Each of the diaphragms 140 includes a solid body having a shape generally comprising a rectangular prism, with a major surface thereof adjacent to and facing a respective major surface of the orifice 124 (e.g., one of the seats 130 thereof).

Forward fluid flow through the valve 110 causes the major surfaces of the diaphragms 140 to be moved against the respective major surfaces and seats 130 of the orifice 124. The fluid flows in through the inlet port 120, then through flow passages between the major surfaces of the diaphragms 140 and the respective major surfaces of the seats 130 of the orifice 124, and then out through the outlet port 122. The seats 130 are contoured to be non-planar and can include, for example, grooves or channels. As the pressure differential across the valve 110 and/or the diaphragms 140 increases, the diaphragms 140 are pressed with greater and greater pressure against the seats 130 and deform to conform to a greater and greater extent to the contour of the seats 130. Accordingly, the flow passages between the diaphragms 140 and the seats 130 become smaller and smaller, which compensates for the increasing pressure differential so as to maintain the flow rate through the valve 110 substantially constant, at least over a range of pressure differentials, such as about 0.1 bar to 10 bars.

Figures 4-6 illustrate components of a hand-operated or manually-operated pressureindependent control valve 110. As illustrated in Figures 4 and 5, the valve 110 includes a handle 150 that is rotatable with respect to the housing 111, and which is sized and otherwise configured to be grasped by a human hand such that a human operator can turn the handle 150 with respect to the housing 111, which generally remains stationary when the valve 110 is installed and in use. As illustrated in Figure 6, a screw 152 is disposed within the flow passage of the housing 111. The screw 152 extends completely through the orifice 124 from a first surface thereof nearest the outlet port 122 and farthest from the handle 150 to an opposing second surface thereof farthest from the outlet port 122 and nearest to the handle 150. A head portion of the screw 152 is embedded in the first surface of the orifice 124 such that the screw 152 cannot move axially through the orifice 124 in a direction toward the second surface thereof. An externally-threaded portion of the screw 152 extends out of the second surface of the orifice 124 and is engaged with a complementary internally-threaded transmission component of the handle 150. Thus, when the handle 150 is turned or rotated with respect to the housing 111, the threaded engagement of the handle 150 and its transmission component with the screw 152 causes the screw 152 to travel axially toward the handle 150. Because the head portion of the screw 152 is embedded in the orifice 124, axial movement of the screw 152 toward the handle 150 also causes the orifice 124 to move axially toward the handle 150. For example, turning the handle 150 in a first direction e.g., clockwise or counter-clockwise) causes the orifice 124 to move toward the handle 150 and turning the handle 150 in a second direction opposite to the first (e.g., clockwise or counter-clockwise) causes the orifice 124 to move away from the handle 150.

Figure 7 illustrates the cartridge 123, the orifice 124, the diaphragms 140, and the screw 152 separated from other components of the valve 110. Figure 8 illustrates the cartridge 123 and the screw 152 separated from other components of the valve 110. As illustrated in Figure 8, the cartridge 123 has an aperture 154 extending through the center thereof, in a vertical direction as illustrated in Figure 8. When the valve 110 is assembled, a bottom surface of the cartridge 123 (as illustrated in Figure 8) rests snugly against a bottom surface of the chamber inside the housing 111 (as illustrated in Figure 6), and a seal or gasket may be provided between the bottom surface of the cartridge 123 and the bottom surface of the chamber, such that fluid is prevented or substantially prevented from flowing through the valve 110 around the cartridge 123. That is, the flow path of the fluid through the valve 110 extends through the aperture 154 extending through the center of the cartridge 123. As noted elsewhere herein, a pressure of the fluid flowing through the fluid flow control valve 110 is generally higher on an upstream side of the fluid flow control valve 110 than on a downstream side of the fluid flow control valve 110. This pressure differential acts to improve the quality of the seal between the bottom surface of the cartridge 123 and the bottom surface of the cavity and to ensure that the flow path through the valve 110 extends through the aperture 154.

When the valve 110 is assembled, the orifice 124 fits snugly into the aperture 154 such that fluid is substantially prevented from flowing between the cartridge 123 and the orifice 124 (that is, through the aperture 154, and thus through the valve 110) except through the grooves or channels formed in the seats 130 of the orifice 124, as described further elsewhere herein. The cartridge 123 includes two rails 156, each positioned at a respective short side of the aperture 154, such that they are located at opposite ends of the aperture 154 as one another, and each extending vertically as illustrated in Figure 8 (that is, in a direction parallel to or aligned with the screw 152). The cartridge 123 also includes two pairs of protrusions or supports 158 adjacent to and facing respective long sides of the aperture 154, such that they are located at opposite sides of the aperture 154 as one another. The cartridge 123 also includes two pairs of undercut grooves 160 adjacent to respective long sides of the aperture 154, such that they are located at opposite sides of the aperture 154 as one another. The cartridge 123 is symmetrical about a first plane extending through the first one of the rails 156, through the screw 152, and through a second one of the rails 156, and is also symmetrical about a second plane that includes a central longitudinal axis of the screw 152 and that is perpendicular to the first plane. Figure 9 illustrates a first diaphragm 140 and a first clip 162 configured to secure the diaphragm 140 to the cartridge 123. The diaphragm 140 includes a solid body having a shape generally comprising a rectangular prism with beveled, chamfered, or rounded edges and corners. As illustrated in Figure 7, when the valve 110 is assembled, the diaphragm 140 is positioned with a first major side surface thereof adjacent to and facing a respective major side surface of the orifice 124, and with a second major side surface thereof, opposite to the first major side surface thereof, adjacent to and facing a first pair of the protrusions 158. The diaphragm 140 can be positioned snugly between the orifice 124 and the protrusions 158, such that the protrusions 158 ensure that the surface of the diaphragm 140 is in contact with the surface of the orifice 124. Because the diaphragm 140 is positioned with a major side surface thereof in contact with and snugly against the orifice 124, fluid is substantially prevented from flowing through the valve 110 except through the grooves or channels formed in the seats 130 of the orifice 124, as described further elsewhere herein.

As also illustrated in Figure 7, when the valve 110 is assembled, the clip 162 has a first end secured in a first one of the undercut grooves 160, a second end secured in a second one of the undercut grooves 160, a first portion that extends from the first end along a first side of the diaphragm 140 in a direction parallel to the axis of the screw 152, a second portion that extends from the second end along a second side of the diaphragm 140 in a direction parallel to the axis of the screw 152, and a third portion that extends from the first portion to the second portion in a direction perpendicular to the axis of the screw 152. Thus, the diaphragm 140 can be positioned snugly between the cartridge 123 and the clip 162, such that the clip 162 ensures that the diaphragm 140 is retained between the protrusions 158 and the orifice 124. The two diaphragms 140 and the two clips 162 illustrated in the drawings can be mirror images of one another across the orifice 123, with one of the diaphragms 140 and one of the clips 162 on one side of the aperture 154, and an identical (or mirror image) diaphragm 140 and clip 162 similarly be positioned on the opposite side of the aperture 154.

Figure 10 depicts a fluid flow control valve 210. The valve 210 can be functionally and mechanically substantially the same as, and can include any of the features of, the valve 110, except that the valve 210 is driven electrically rather than manually. Thus, Figure 10 illustrates components of an electrically-operated or electrically-driven pressure-independent control valve 210. As illustrated in Figure 10, the valve 210 includes an auxiliary housing 212 configured to house an electric motor and other electric components, such as a battery. Figure 11 illustrates that the valve 210 includes a screw 252 that can be similar to or the same as the screw 152, and that an externally-threaded portion of the screw 252 is engaged with a complementary internally- threaded portion of a transmission component 214 that is coupled at one end to the electric motor housed inside the auxiliary housing 212 and at the other end to the screw 252. Thus, the electric motor can be operated to turn the transmission component 214, and thereby to move the screw 252. The electric motor can be controlled to turn the transmission component 214 in a first direction (e.g., clockwise or counter-clockwise) to move an orifice toward the auxiliary housing 212 and to turn the transmission component 214 in a second direction opposite to the first (e.g., clockwise or counter-clockwise) to move the orifice away from the auxiliary housing 212.

Figure 12 illustrates a perspective view of an orifice 300 for use in either the valve 110 or the valve 210, Figure 13 illustrates another perspective view thereof, and Figure 14 illustrates an end view thereof. As described elsewhere herein, the orifice 300 includes a body having a shape generally comprising a rectangular prism. As illustrated in Figures 12-14, the orifice 300 includes a pair of grooves 304, which may be undercut grooves, formed in opposing side surfaces thereof, into which rails (e.g., rails 156) are configured to fit. When a valve is fully assembled, the rails e.g., rails 156) are held captive within the grooves 304, such that the orifice 300 may slide and move axially or longitudinally along the rails, but cannot move in other directions or rotate with respect to the rails. As further illustrated in Figures 12-14, the orifice 300 includes a conduit 306 extending through a center thereof in a direction aligned with the grooves 304, through which a screw (e.g., screw 152) is configured to extend. As illustrated in Figures 12-14, one end of the conduit 306 can be flared radially outward to accommodate the head portion of the screw.

As described elsewhere herein, the orifice 300 is formed with a pair of seats 302 defined at opposing major side surfaces thereof. Each of the seats 302 is contoured to be non-planar and can include, for example, grooves or channels having curvatures defined by splines. For example, as illustrated in Figures 12-14, the contoured shape of each of the seats 302 may include one or more outermost shallow channels, one or more intermediate channels having intermediate depths, and one or more innermost or central deep channels. In this context, “outermost,” “intermediate,” and “innermost” (or “central”) terminology refers to locations from left to right as illustrated in Figure 14, which is in a direction aligned with an axis extending from a first rail to a second rail of a cartridge of the valve. Also, in this context, “shallow,” “intermediate depth,” and “deep” are relative terms that indicate that certain features are deeper or shallower than others without indicating any quantitative information regarding the depths. When the valve 110 or 210 is assembled and in use, the contoured surfaces of the orifice 300 interact with the diaphragms (e.g., diaphragms 140) to control the rate at which fluid flows through the valve as the upstream fluid pressure varies. For example, a cross-sectional flow area through the valve can be defined by the sum of a first cross-sectional area of a first gap between a first one of the contoured surfaces of the orifice 300 and the (at least initially, or in a rest condition) planar surface of a first one of the diaphragms adjacent thereto and a second cross- sectional area of a second gap between a second one of the contoured surfaces of the orifice 300 and the (at least initially, or in a rest condition) planar surface of a second one of the diaphragms adjacent thereto, where those cross-sectional areas are measured at the respective top ends of the diaphragms (as illustrated in Figure 6), that is, at ends of the diaphragms farthest from the outlet port (e.g., outlet port 122).

As noted elsewhere herein, when urged against the seats 302 of the orifice 300, the diaphragms deform, the degree of deformation increasing with increasing pressure differential across the diaphragm. As the deformation of the diaphragm increases, the cross-sectional areas of the flow control passages between the diaphragms and the seats 302 become smaller. The valves described herein are configured such that, over the range of pressure differentials of interest, the changing cross-sectional areas of the flow control passages offset the changing pressure differential so as to maintain a substantially constant flow rate through the valve. For example, with respect to the valve 110, as the pressure differential across the valve 110 and/or the diaphragms 140 increases, the diaphragms 140 are pressed with greater and greater pressure against the seats 130 and deform to conform to a greater and greater extent to the contour of the seats 130. Accordingly, the flow passages between the diaphragms 140 and the seats 130 become smaller and smaller, which compensates for the increasing pressure differential so as to maintain the flow rate through the valve 110 substantially constant, at least over a range of pressure differentials.

As illustrated in Figures 12 and 13, the depths of the channels formed in the seats 302 in the contoured surfaces of the orifice 300 vary along a length of the orifice 300 aligned with the grooves 304 and the conduit 306. In general, the depths of the channels increase in a direction from a first, upstream end of the orifice 300 to a second, downstream end of the orifice 300 (where the flared end of the conduit 306 is located). Thus, at constant pressure differentials across the valves described herein and the orifices and diaphragms thereof, the cross-sectional areas of the flow control passages between the diaphragms and the seats 302 of the orifice 300 become larger in a downstream direction. Thus, the cross-sectional flow area through the valve is generally defined by the sum of cross-sectional areas between the contoured surfaces of the orifice 300 and the surfaces of the diaphragms at the upstream ends of the diaphragms, that is, where such cross-sectional areas are smallest.

As described elsewhere herein, the orifice 300 can be moved axially or longitudinally with respect to other components of the valve, including the diaphragms (e.g., diaphragms 140). Because the depths of the channels formed in the seats 302 in the contoured surfaces of the orifice 300 vary along a length of the orifice 300 in the direction of such movement, such movement changes the cross-sectional areas of the gaps between the orifice 300 and adjacent diaphragms. In particular, moving the orifice 300 in an upstream direction increases the cross- sectional areas of the gaps and moving the orifice 300 in a downstream direction decreases the cross-sectional areas of the gaps.

By moving an orifice of one of the valves described herein in either an upstream direction or a downstream direction with respect to the diaphragms, an operator can control or adjust the flowrate of the fluid flow flowing through the valve. For example, a user can install one of the pressure-independent control valves described herein and, either manually or electrically, adjust the location of the orifice with respect to the diaphragms, to provide a first constant flow rate through the valve (e.g., a volume flow per unit time, such as gallons per minute), which can be independent of the upstream pressure of the fluid. The user can further adjust the location of the orifice with respect to the diaphragms to provide a second constant flow rate through the valve, which can be independent of the upstream pressure of the fluid, and which can be either greater than or less than the first constant flow rate. In particular, the user can adjust the location of the orifice downward or downstream to reduce the constant flow rate through the valve, or adjust the location of the orifice upward or upstream to increase the constant flow rate through the valve. Such adjustments can be made live, that is, as fluid is flowing through the valve. Such adjustments can also be continuously variable (that is, the flow rate can be adjusted as finely as is possible by hand or by electric motor, rather than in set increments).

The adjustable pressure-independent control valves described herein may be springless. That is, they may be without, and not incorporate, metallic springs, coil springs, or other mechanical springs.

Aspects of the various embodiments described above can be combined to provide further embodiments. In general, in the following claims, the terms used should not be construed to limit the claims to the specific embodiments disclosed in the specification and the claims, but should be construed to include all possible embodiments along with the full scope of equivalents to which such claims are entitled.

U.S. Provisional Patent Application No. 63/483,208 fded February 3, 2023, is incorporated herein by reference, in its entirety.

Claims

1. An adjustable pressure-independent fluid flow control valve, comprising: a housing defining a fluid flow passage extending therethrough, the housing having openings for flow into and out of the fluid flow passage; an orifice disposed in the fluid flow passage of the housing, the orifice having a seat at an end thereof; and an elastomeric diaphragm disposed in the fluid flow passage of the housing, the diaphragm having a surface that is urged against the seat of the orifice by fluid flow through the valve such that a flow rate of fluid through the valve is constant as upstream pressure changes; wherein the orifice can be moved with respect to the diaphragm to adjust the flow rate of the fluid through the valve.

2. The adjustable pressure-independent fluid flow control valve of claim 1, wherein the adjustable pressure-independent fluid flow control valve does not include any springs.

3. The adjustable pressure-independent fluid flow control valve of claim 1, wherein the adjustable pressure-independent fluid flow control valve does not include any coil springs.

4. The adjustable pressure-independent fluid flow control valve of claim 1, wherein the valve is configured to be manually actuated to move the orifice with respect to the diaphragm.

5. The adjustable pressure-independent fluid flow control valve of claim 1, wherein the valve is configured to be electrically actuated to move the orifice with respect to the diaphragm.

6. The adjustable pressure-independent fluid flow control valve of claim 1, further comprising a cartridge, wherein the orifice is held in position by the cartridge.

7. The adjustable pressure-independent fluid flow control valve of claim 6, wherein the orifice includes grooves and the cartridge includes rails seated within the grooves.

8. The adjustable pressure-independent fluid flow control valve of claim 7, wherein the orifice can be moved linearly with respect to the diaphragm along the rails to adjust the flow rate of the fluid through the valve.

9. An adjustable pressure-independent fluid flow control valve, comprising: a housing defining a fluid flow passage extending therethrough, the housing having openings for flow into and out of the fluid flow passage; an orifice disposed in the fluid flow passage of the housing, the orifice having a seat at an end thereof, the orifice having a shape generally comprising a rectangular prism; and an elastomeric diaphragm disposed in the fluid flow passage of the housing, the diaphragm having a shape generally comprising a rectangular prism, the diaphragm having a surface that is urged against the seat of the orifice by fluid flow through the valve such that a flow rate of fluid through the valve is constant as upstream pressure changes.

10. The adjustable pressure-independent fluid flow control valve of claim 9, wherein the orifice can be moved with respect to the diaphragm to adjust the flow rate of the fluid through the valve.

11. An adjustable pressure-independent fluid flow control valve, comprising: a housing defining a fluid flow passage extending therethrough, the housing having openings for flow into and out of the fluid flow passage; an orifice disposed in the fluid flow passage of the housing, the orifice having a first seat at a first end thereof and a second seat at a second end thereof, the second end opposite to the first end; a first elastomeric diaphragm disposed in the fluid flow passage of the housing; and a second elastomeric diaphragm disposed in the fluid flow passage of the housing; wherein the first diaphragm has a first surface that is urged against the first seat of the orifice by fluid flow through the valve and the second diaphragm has a second surface that is urged against the second seat of the orifice by fluid flow through the valve such that a flow rate of fluid through the valve is constant as upstream pressure changes.

12. The adjustable pressure-independent fluid flow control valve of claim 11, wherein the orifice can be moved with respect to the diaphragms to adjust the flow rate of the fluid through the valve.

13. The adjustable pressure-independent fluid flow control valve of claim 11, wherein the orifice has a shape generally comprising a rectangular prism and the first and second diaphragms each have a shape generally comprising a rectangular prism.

14. The adjustable pressure-independent fluid flow control valve of claim 13, wherein the orifice can be moved with respect to the diaphragms to adjust the flow rate of the fluid through the valve.