FIELD OF THE INVENTION

The invention is related to the field of valves, and in particular, to an improved diaphragm valve.

BACKGROUND

Diaphragm valves were developed for use in industrial settings, with applications ranging from bio-pharmaceutical, medical, industrial, food and beverage, etc. The most simple diaphragm valve has a valve body having two or more ports, a diaphragm, and a valve seat. The diaphragm contacts the valve seat to close the valve. Instead of traditional full-bore valve seats, diaphragms may alternatively be constructed to contact a "weir" (also known as a saddle) to seal the valve closed. The weir or saddle type is the most common form of the diaphragm valve.

Diaphragm valves may come in many variations, such as 2/2 valves, 3/2 valves etc. Physical members may actuate the valve states, or alternatively, diaphragms may be controlled with a pilot fluid. Like most valves, diaphragm valves may be manual or automated.

Typically, diaphragm valves require an external biasing member to return to a non- actuated position, and often requires the aid of fluid pressure to aid in actuation. There is a need for a diaphragm valve that reliably returns to a non-actuated position even during low-flow or no-flow conditions. There is also a need, for a normally closed diaphragm valve, for a valve interface that reliably remains sealed during low-flow or no-flow conditions. The embodiments described below overcome these and other problems and an advance in the art is achieved. The embodiments described below provide a compliant valve member assembly that reliably returns to a non-actuated state, simplifies manufacturing, and reduces valve costs.

SUMMARY OF THE INVENTION

According to an embodiment, a valve member having an integral construction comprises a valve seat, a diaphragm portion having a first side and a second side, and a diaphragm boss protruding from the second side. The valve member additionally comprises a biasing member having a sealing portion disposed to contact the valve seat upon actuation of the valve member, a biasing portion, and a biasing boss protruding towards, and in contact with, the diaphragm boss, configured to receive a force from the diaphragm boss upon actuation of the valve member that compresses the biasing portion and separates the sealing portion from the valve seat.

According to an embodiment, a method of assembling a diaphragm valve comprises the steps of forming a valve member comprising a diaphragm boss, forming a biasing member comprising a biasing boss, forming a valve body, inserting the biasing member into the valve body, and inserting the valve member into the valve body such that the diaphragm boss contacts the biasing boss.

ASPECTS

A valve assembly is provided. The valve assembly comprises a valve member having an integral construction. The valve member comprises: a valve seat, a diaphragm portion having a first side and a second side, and a diaphragm boss protruding from the second side. The valve assembly also comprises a biasing member. The biasing member comprises: a sealing portion disposed to contact the valve seat upon actuation of the valve member, a biasing portion, and a biasing boss protruding towards, and in contact with, the diaphragm boss, configured to receive a force from the diaphragm boss upon actuation of the valve member that compresses the biasing portion and separates the sealing portion from the valve seat.

Preferably, the valve assembly comprises a valve body defining a plurality of ports, wherein the valve body is configured to house the valve member.

Preferably, the valve body comprises a top plate and a bottom plate, wherein the valve member defines a plurality of seals therein.

Preferably, the diaphragm portion comprises a convex portion in fluid communication with a pilot port.

Preferably, the diaphragm portion comprises a convoluted portion in fluid communication with a pilot port.

Preferably, the plurality of ports comprises: a first port, a second port, and a pilot port, wherein the pilot port is in fluid communication with a diaphragm portion, and wherein a pilot fluid pressure force upon the diaphragm portion is configured to actuate the valve member to compress the biasing member to form an open state of the valve assembly, wherein the first port is placed in fluid communication with the second port.

Preferably, the diaphragm portion comprises a first side in fluid communication with the first port, and a second side in fluid communication with the pilot port.

Preferably, the valve assembly is configured to change actuation states when a force upon the second side exceeds a combination of a force exerted upon the first side and a biasing force provided by the biasing member.

Preferably, a projection of the valve member defines at least one member port therein, configured to provide fluid communication through the valve member and between a first port and a second port.

Preferably, the biasing portion comprises a plurality of pleats.

Preferably, the biasing member comprises a cavity having a size and dimension to be indexable over an alignment boss defined by the valve body.

Preferably, the valve member comprises a gasket portion configured to isolate the second port from the pilot port, and wherein a projection defined by the valve member is configured to isolate the second port from the first port when the valve assembly is in a closed state.

Preferably, the valve member and the biasing member comprise a resilient material.

A method of assembling a diaphragm valve is provided. The method comprises the steps of: forming a valve member comprising a diaphragm boss, forming a biasing member comprising a biasing boss; forming a valve body; inserting the biasing member into the valve body; and inserting the valve member into the valve body such that the diaphragm boss contacts the biasing boss.

Preferably, the valve body comprises an alignment boss.

Preferably, the biasing member defines a hollow cavity.

Preferably, the method comprises the step of indexing the hollow cavity over the alignment boss.

Preferably, the step of inserting the valve member into the valve body comprises the steps of: placing the valve member on a bottom plate, placing a top plate on the bottom plate, and creating a seal between the top and bottom plates with a sealing portion of the valve member. Preferably, the step of inserting the valve member into the valve body comprises the steps of: defining a first port with the valve body, defining a second port with the valve body, and defining a pilot port with the valve body.

Preferably, the method comprises the steps of: placing a first side of a diaphragm portion of the valve member in fluid communication with the first port, placing a second side of the diaphragm portion of the valve member in fluid communication with the pilot port, and placing a member port defined by the valve member in fluid communication with the second port.

BRIEF DESCRIPTION OF THE DRAWINGS

The same reference number represents the same element on all drawings. The drawings are not necessarily to scale.

FIG. 1 is a cross-sectional view of a diaphragm valve in an example embodiment in a closed state.

FIG. 2 is a cross-sectional view of the diaphragm valve of FIG. 1 in an open state.

FIG. 3 is an isometric view of a biasing member according to an embodiment.

FIG. 4 is an isometric top view of a valve member according to an embodiment.

FIG. 5 is an isometric bottom view of the valve member of FIG. 4.

FIG. 6 is an isometric top view of a valve member according to an alternate embodiment.

FIG. 7 is an isometric bottom view of the valve member of FIG. 6.

FIG. 8 is a cross-sectional view of a diaphragm valve in another example embodiment in a closed state.

FIG. 9 illustrates a method of forming a valve assembly according to an embodiment.

DETAILED DESCRIPTION OF THE INVENTION

FIGS. 1-9 and the following description depict specific examples to teach those skilled in the art how to make and use the best mode of embodiments of a diaphragm valve. For the purpose of teaching inventive principles, some conventional aspects have been simplified or omitted. Those skilled in the art will appreciate variations from these examples that fall within the scope of the invention. Those skilled in the art will appreciate that the features described below can be combined in various ways to form multiple variations of the invention. As a result, the invention is not limited to the specific examples described below, but only by the claims and their equivalents.

FIGS. 1 and 2 illustrate a cross section of a valve assembly 100 according to an embodiment. The valve assembly 100 illustrated provides a valve member 102 disposed in a valve body 104. In an embodiment, the valve body 104 comprises a top plate 106 and a bottom plate 108 that captures the valve member 102 therebetween. In an embodiment, a gasket portion 109 of the valve member 102 is sandwiched between the top plate 106 and the bottom plate 108 so to form a seal. Other methods may be used to hold the valve member 102 into the valve, however. For example, a groove or channel 1 1 1 may be formed in the outer edge of the valve member 102 and a lip or bead 1 13 may be formed on the gasket portion 109 that fits into the groove defined by the valve body 104. In an embodiment, the valve body defines a first port 1 10, a second port 1 12, and a pilot port 1 14. A fluid, fluid/gas mixture, slurry, or other solution may be introduced into a port 1 10, 112 and may pass through the valve assembly 100 to exit through the opposing port 1 12, 1 10. In an embodiment, the first port 1 10 is configured as an input port, and the second port 1 12 is configured as an output port. Fluid may pass from the input to output port when the valve assembly 100 is in an open configuration (FIG. 2). When the valve assembly 100 is in a closed configuration (FIG. 1), fluid is prevented from communicating between the first port 1 10 and the second port 1 12. The pilot port 1 14 provides fluid communication to a diaphragm portion 126 of the valve member 102, and the pressure of fluid supplied to the pilot port 1 14 provides a force to actuate the valve member 102. In the figures, the valve assembly 100 is illustrated as a normally closed valve. Pilot fluid provided to the pilot port 1 14 may therefore change the actuation state of the valve assembly from closed to open, as will be further described below. It should be noted that the valve assembly 100 may comprise either a normally closed or normally open valve.

With continuing reference to FIG. 1, a fluid introduced into the first port 1 10 is not in fluid communication with the second port 1 12. In this case, a diaphragm portion 126 of the valve member 102 causes portions of the valve assembly 100, as will be further described herein, to physically block fluid from passing to the second port 1 12. When the valve assembly 100 is actuated, such that the diaphragm portion 126 moves to the open position, fluid introduced into the first port 1 10 is placed in communication with the second port 1 12. In operation, the diaphragm portion 126 moves between two positions, an upper position and a lower position (as illustrated in FIG. 1 and FIG. 2, respectively).

A resilient biasing member 1 17 is disposed in the valve body 104 and in contact with the valve member 102. The biasing member 1 17 serves to provide a biasing force against the valve member 102 so to return the valve member 102 to a non-actuated state, such as when a pilot fluid exerts a pressure upon the diaphragm portion 126 that is less than the force exerted upon the diaphragm portion 126 by the biasing member 1 17. In prior art diaphragm valves, the assembly typically relies, at least partially, on an input fluid pressure exerting a force on a diaphragm to return a diaphragm to a non-actuated position. In the present embodiments, the diaphragm portion 126 returns to the non- actuated position due to forces exerted thereupon by the biasing member 1 17— even in the absence of fluid pressure to the first port 1 10. In an embodiment, a biasing boss 1 19 that protrudes from the biasing member 1 17 contacts a diaphragm boss 1 15 that protrudes from the valve member 102. When a pressurized pilot fluid acts upon a first side 122 of the diaphragm portion 126, the diaphragm portion 126 is biased downward (as illustrated in FIG. 2), and forces the diaphragm boss 1 15 to exert a pressure upon the biasing boss 1 19. A biasing portion 120 of the biasing member 1 17 exerts an opposing force, but may be overcome by the force of the diaphragm boss 1 15 having a pilot pressure acting thereupon. The biasing portion 120 is a resilient portion of the biasing member 1 17 that allows for the biasing member 117 to compress so to follow an overall substantially linear motion path.

FIG. 2 illustrates an embodiment of a normally closed valve in the open, or actuated, state. The biasing portion 120 of the biasing member 117 creates a biasing force that promotes contact between a sealing portion 1 16 of the biasing member 1 17 and a valve seat 118 defined by the valve member. As illustrated, the biasing portion 120 of the biasing member 1 17 exerts a force upon the diaphragm boss 1 15, but this force is overcome by the force of the diaphragm boss 1 15 having a pilot pressure acting upon the first side 122 of the diaphragm portion 126, the valve assembly 100 is in an open state. Once in the open state, fluid introduced into the first port 1 10 may pass through a fluid path 128 created when the sealing portion 1 16 and valve seat 1 18 are separated, and this allows the fluid to act upon a second side 124 of the of the diaphragm portion 126. Therefore, the pressure exerted upon the first side 122 by a pilot fluid must exceed the combined force of the fluid acting upon the second side 124 of the of the diaphragm portion 126 and the force exerted upon the diaphragm boss 1 15 by the biasing member 1 17 in order to maintain the valve in an open state.

When in the open state, fluid introduced to a second side 124 of the diaphragm portion 126 provides additional forces that promote maintaining the sealing portion 1 16 of the valve member 102 in contact with the valve seat 1 18, and thus compliment the forces exerted by the biasing boss 1 19 upon the diaphragm boss 1 15. The valve member 102 may be configured such that the default position is either the upper (closed, as illustrated) position or the lower (open, as illustrated) position. In order for a normally closed embodiment of the valve assembly 100 to be opened, pilot fluid introduced to the pilot port 1 14 exerts a force on a first side 122 of the diaphragm portion 126. When this force exceeds the opposing force provided by the biasing portion 120, the valve assembly 100 opens. As noted, in the open state, this force is combined with the opposing force from fluid introduced to the second side 124 of the valve member 102. As the diaphragm portion 126 of the valve member 102 moves downward (as illustrated in FIG. 2), the seal provided by the sealing portion 116 contacting the valve seat 118 is broken, thus revealing a fluid path 128. This allows fluid introduced into the first port 1 10 to communicate, via the fluid path 128, with the second port 1 12. When there is no force applied to either area 122, 124, (or if the forces exerted upon 122 and 124 are substantially equal) the diaphragm portion 126 may be configured to snap, return to, or maintain a default position. It should be noted that the area of the first side 122 may be adjusted to allow for variations in the available pilot fluid pressure and/or the operating pressure range of the process fluid provided to the valve assembly 100. Additionally, the size and dimensions of the biasing portion 120 contributes to the stroke and strength related to actuation of the diaphragm portion 126 and therefore also relates to the size of the fluid path 128.

Turning to FIG. 3, an embodiment of the biasing member 1 17 is illustrated. The biasing member 1 17 is molded, injection molded, machined, or otherwise manufactured, from a resilient material or a combination of resilient materials— for example rubber, polyurethane, or the like. In an embodiment, the valve member 102 is of an integral construction, thus it is formed as a single unit. In an embodiment, the valve member 102 is made from a single piece of material. However, multi -material construction, such as overmolding, for example without limitation, is contemplated. The biasing member is generally radially symmetric in an embodiment. In an embodiment, the biasing portion 120 comprises a series of pleats 127 that aid in the compression and extension of the biasing member 1 17. Pleats 127 are not strictly required, however, as other structures for a compression and extension of the biasing member 1 17 are also contemplated. A cavity 123 may be defined by the biasing member 1 17 in an embodiment. However, no cavity 123 may be present and the biasing member 1 17 may be substantially solid in another embodiment. In yet another embodiment, the biasing member 1 17 may comprise a hollow portion, but without having a cavity 123 that opens to an external surface of the biasing member 1 17. The cavity 123 may aid in alignment of the biasing member 1 17 relative to the valve body 104 by indexing over an alignment boss 125 with the valve body 104 (see FIG. 1 and 2, for example). In an embodiment, the alignment boss 125, the cavity 123, and the valve member 102 are substantially concentric about a center of the alignment boss 125. In another embodiment, the cavity 123 may aid in alignment of the biasing member 1 17 relative to the valve body 104 by indexing within the alignment boss 125.

Turning to FIGS. 4 and 5, an embodiment of a valve member 102 is illustrated. A plurality of the valve member 102 portions are generally circular in nature. The valve member 102 is molded, injection molded, machined, or otherwise manufactured, from a resilient material or a combination of resilient materials, for example rubber, polyurethane, or the like. In an embodiment, the valve member 102 is of an integral construction, thus it is formed as a single unit. In an embodiment, the valve member 102 is made from a single piece of material. However, multi -material construction, such as overmolding, for example without limitation, is contemplated. A plurality of member ports 130 is defined by the valve member 102. As can be seen in FIGS. 1 and 2, the member ports 130 provide means for fluid path 128 to fluidly communicate with the second port 1 12. FIG. 4 is an isometric top view of a valve member according to an embodiment. FIG. 5 is an isometric bottom view of FIG. 4.

FIGS. 6 and 7 illustrate an alternate embodiment of a valve member. FIG. 6 is an isometric top view of a valve member 102, and FIG. 7 is an isometric bottom view. In this embodiment, the diaphragm 126 is convoluted, as opposed to the relatively flat diaphragm 126 shown in FIGS. 4 and 5. In that embodiment, the flat diaphragm comprises a convex region. The convoluted valve member 102 allows for a greater diaphragm throw, and also provides greater surface areas of the first and second sides 122, 124, thus the forces acting upon the valve member 102 by pilot fluids and process fluids, respectively, are amplified. Altering the size and shape of the diaphragm 126, convoluted or flat, is therefore provided as means for adjusting the sensitivity of the valve assembly 100 to different pilot pressures and process fluid pressures. Additionally, by changing the flexibility, durometer, resilience, shape, dimension, or other physical property of the biasing member 1 17 and/or valve member 102, the force necessary to actuate the valve may be altered. In a similar vein, the stroke length may also be altered by adjusting the same or similar valve member 102 properties. FIG. 8 illustrates a cross section of a valve assembly 100 according to an alternate embodiment, utilizing the valve member of FIGS. 6 and 7.

The embodiment of FIG. 8 illustrates a valve member 102 disposed in a valve body 104. In an embodiment, the valve body 104 comprises a top plate 106 and a bottom plate 108 that captures the valve member 102 therebetween. In an embodiment, a gasket portion 109 of the valve member 102 is sandwiched between the top plate 106 and the bottom plate 108 so to form a seal. Other methods may be used to hold the valve member 102 into the valve, however. For example, a groove or channel 1 11 may be formed in the outer edge of the valve member 102 and a lip or bead 1 13 may be formed on the gasket portion 109 that fits into the groove defined by the valve body 104. In an embodiment, the valve body defines a first port 1 10, a second port 1 12, and a pilot port 1 14. A fluid, fluid/gas mixture, slurry, or other solution may be introduced into a port 1 10, 1 12 and may pass through the valve assembly 100 to exit through the opposing port 1 12, 1 10. In an embodiment, the first port 1 10 is configured as an input port, and the second port 1 12 is configured as an output port. Fluid may pass from the input to output port when the valve assembly 100 is in an open configuration. When the valve assembly 100 is in a closed configuration, as illustrated, fluid is prevented from communicating between the first port 1 10 and the second port 1 12. The pilot port 1 14 provides fluid communication to a diaphragm portion 126 of the valve member 102, and the pressure of fluid supplied to the pilot port 1 14 provides a force to actuate the valve member 102. In the figure, the valve assembly 100 is illustrated as a normally closed valve. Pilot fluid provided to the pilot port 1 14 may therefore change the actuation state of the valve assembly from closed to open. It should be noted that the valve assembly 100 may comprise either a normally closed or normally open valve. With continuing reference to FIG. 8, a fluid introduced into the first port 1 10 is not in fluid communication with the second port 1 12. In this case, a diaphragm portion 126 of the valve member 102 physically blocks fluid from passing to the second port 1 12. When the valve assembly 100 is actuated, such that the diaphragm portion 126 moves to the open position, fluid introduced into the first port 110 is placed in communication with the second port 1 12. In operation, the diaphragm portion 126 moves between two positions, an upper position and a lower position.

A resilient biasing member 1 17 is disposed in the valve body 104 and in contact with the valve member 102. The biasing member 1 17 serves to provide a biasing force against the valve member 102 so to return the valve member 102 to a non-actuated state, such as when a pilot fluid exerts a pressure upon the diaphragm portion 126 that is less than the force exerted upon the diaphragm portion 126 by the biasing member 1 17. In prior art diaphragm valves, the assembly typically relies, at least partially, on an input fluid pressure exerting a force on a diaphragm to return a diaphragm to a non-actuated position. In the present embodiments, the diaphragm portion 126 returns to the non- actuated position due to forces exerted thereupon by the biasing member 1 17— even in the absence of fluid pressure to the first port 1 10. In an embodiment, a biasing boss 1 19 that protrudes from the biasing member 117 contacts a diaphragm boss 1 15 that protrudes from the valve member 102. When a pressurized pilot fluid acts upon a first side 122 of the diaphragm portion 126, the diaphragm portion 126 is biased downward (as illustrated in FIG. 2), and forces the diaphragm boss 1 15 to exert a pressure upon the biasing boss 1 19. A biasing portion 120 of the biasing member 1 17 exerts an opposing force, but may be overcome by the force of the diaphragm boss 1 15 having a pilot pressure acting thereupon. The biasing portion 120 is a resilient portion of the biasing member 1 17 that allows for the biasing member 1 17 to compress so to follow an overall substantially linear motion path.

Valves traditionally comprise many components to create various seals, promote guidance, and ensure correct seating. The combination of valve member 102 and biasing member 1 17, by virtue of their simple construction, obviates the need for additional valve components other than a valve body 104 in which it is installed. In particular, the combination of valve member 102 and biasing member 1 17 is made such that they function as all the necessary seals, a biasing member 117, a sealing portion 1 16 that mates to the valve seat 1 18, fluid paths (member ports 130), diaphragm 126, and pilot fluid receiving portions (first side 122). Extra seals are not necessary, as the gasket portion 109 and the projection 132 proximate the member ports 130 provide seals proximate both the first and second ports 1 10, 1 12. Additionally, the gasket portion 109 provides a seal that isolates the pilot port 1 14 from other ports in the valve assembly 100. It is therefore possible to construct a pilot-actuated valve with only three parts: a valve member 102, a biasing member 1 17, and a valve body 104. Besides drastically reducing manufacturing costs, operation is made more consistent, as the valve seat 1 18 and sealing portion 1 16 are self-aligning, by virtue of construction.

FIG. 9 illustrates a method of forming a valve assembly 100 according to an embodiment. In step 200, a valve member 102 is formed. As noted above, the valve member 102 is molded, injection molded, machined, or otherwise manufactured, from a resilient material. The valve member 102 is formed having a diaphragm boss 1 15. In an embodiment, member ports 130 are defined in this step. In step 202, the biasing member 1 17 is formed. Like the valve member 102, the biasing member 1 17 is molded, injection molded, machined, or otherwise manufactured, from a resilient material. The biasing member 1 17 is formed having a biasing boss 1 19 and a hollow cavity 123, as described above. The cavity 123 aids in alignment of the biasing member 1 17 relative to the valve body 104 by indexing over an alignment boss 125 with the valve body 104, which is formed in step 204. Aligning inside an alignment boss 125 is also contemplated. In step 206, the biasing member is placed in the valve body 104 so that the alignment boss 125 is inserted into the hollow cavity 123 to maintain alignment between the biasing member 1 17 and the valve member 102. In step 208, the valve member 102 is inserted into the valve body 104 so that the diaphragm boss 1 15 mates to the biasing boss 1 19. In an embodiment, the member port(s) 130 is/are aligned with a port 1 12 defined by the valve body 104. In an embodiment, the valve member 102 is installed in the valve body 104 such that the valve member 102 defines a plurality of seals, as described herein.

The detailed descriptions of the above embodiments are not exhaustive descriptions of all embodiments contemplated by the inventors to be within the scope of the invention. Indeed, persons skilled in the art will recognize that certain elements of the above-described embodiments may variously be combined or eliminated to create further embodiments, and such further embodiments fall within the scope and teachings of the invention. It will also be apparent to those of ordinary skill in the art that the above- described embodiments may be combined in whole or in part to create additional embodiments within the scope and teachings of the invention.

Thus, although specific embodiments of, and examples for, the invention are described herein for illustrative purposes, various equivalent modifications are possible within the scope of the invention, as those skilled in the relevant art will recognize. The teachings provided herein can be applied to other devices and method, and not just to the embodiments described above and shown in the accompanying figures. Accordingly, the scope of the invention should be determined from the following claims.