1. Field
The disclosure pertains to valves that contain and control release of fluids from cylinders or containers to other parts of a system while preventing backflow of such fluids within the system.
2. Related Art
Many industries such as the semiconductor industry require the use of air-reactive gases such as metal hydrides (e.g., arsine, phosphine, silane, etc.) and corrosive gases (e.g., boron trifluoride, boron trichloride, tungsten hexafluoride, etc.). Examples of other air-reactive gaseous compounds include, without limitation, germanes, polysilanes such as trisilane, silyl-germanes, silylamines such as trisilylamine, and organometallic metal compounds.
In many semiconductor applications, process gases are typically supplied in storage cylinders at high pressure, with sufficient pressure reduction being maintained downstream of the cylinder to facilitate withdrawal of the gaseous product from the cylinder and delivery to a suitable location or tool for use in a system application. The downstream pressure is typically regulated using a pressure regulator or a similar device that is disposed in-line in the system and/or attached to the valve of the storage cylinder.
In recent years, because of safety concerns, alternate packaging methods known as the subatmospheric gas system (SAGS) have been developed to supply many of these gases. The term SAGS is defined as a system that includes a gas cylinder which under normal operation allows for a gas flow from a cylinder only when the cylinder valve outlet is exposed to a pressure of less than one atmosphere. By utilizing a SAGS system, gases are prevented from sudden escape of the cylinder and any inadvertent system leaks will not result in a rapid and excessive release of such gases to the surrounding environment.
In addition, certain new precursors are emerging for use in semiconductor and other manufacturing operations, where the precursors can be in the form of low vapor pressure liquids. Trisilane is an example which is a liquid with vapor pressure of 95.5 torr (12.73 kPa) at 0° C. Other examples include tetramethylsilane (4 MS), trisilamine (TSA), and octafluorocyclopentene (C5F8). Some of these new products are classified as pyrophoric. Typically, these products are stored in cylinders normally used for pressurized gases.
While the SAGS and low vapor pressure liquid systems minimize any uncontrolled release of dangerous compounds to the surrounding environment, they also present opportunities for back-diffusion of a contaminant (e.g., air) from outside during shipping, storage and/or usage of the gases or liquids. For example, if the storage cylinder valve is loose or opened by mistake, and/or if there is a leak anywhere else within the fluid line during system operation, ambient atmospheric components that are at greater pressure than the cylinder contents can enter into the cylinder. This in turn can result in explosive reactions for pyrophoric or flammable products, or to corrosion of valve and/or other cylinder components for corrosive gases. Conventional SAGS systems provide no safety mechanisms for preventing air infiltration and contamination due to back diffusion or flow into the cylinder.
Many applications using the types of sub-atmospheric gaseous or low vapor pressure liquid products in the semiconductor industry are also delivered in conjunction with other purge gases such as nitrogen for purging and cleaning the delivery lines before and after the delivery of the product. There always exists a possibility that the purge gas can diffuse back in the cylinder contaminating the product if one or more control valves are opened or closed by mistake.
In addition, even air reactive gases stored under higher pressures can experience air back diffusion during a particular application. For example, many semiconductor manufacturing operations are carried out under vacuum, such that the gaseous compound is withdrawn from a high pressure cylinder under vacuum even though it may be at a pressure higher than the ambient pressure. During a particular application in which the gas has been continuously withdrawn from a cylinder, the pressure within the cylinder can eventually drop below ambient pressure, which can then lead to potential back-diffusion of air within the cylinder if there is an inadvertent leak within the system or a cylinder valve is not closed properly or left open by mistake.
Thus, there are considerable safety and purity concerns associated with storing and using such air-reactive gases and liquid products without the assurance that backflow of fluids into the storage cylinder can be prevented.
A valve device, valve member and method are disclosed herein for delivering air-reactive and/or other compounds from a cylinder or supply source to a particular application while effectively preventing the possibility of any undesirable flow or diffusion of fluids back into the cylinder.
A valve device is provided that is securable to a cylinder and comprises a housing including a central passage in fluid communication with a first connection port that connects with a cylinder, and a second connection port including a passage that is in fluid communication with the central passage. The second connection port is configured to connect with a fluid flow line. A valve member is disposed within the second connection port and includes a movable member that engages with a seat to provide a fluid tight seal for the valve member in a closed position. The movable member is configured to be moved away from the seat so as to open the valve member and permit fluid to flow from the central passage of the valve housing around the movable member and through the second connection port while substantially preventing a backflow of fluids from a location external to the valve housing into the central passage.
In another embodiment, a valve member is provided comprising a hollow plug including a chamber, a first end and a second end, where the first and second ends include openings. A movable member is disposed within the chamber, and a biasing member is also provided, where the biasing member forces the movable member toward the first end of the plug so as to engage with a seat defined at the first end of the valve member. The movable member and seat engage to form a fluid tight seal to prevent fluids from entering the chamber via the first end opening, and the movable member is movable away from the seat to permit access of fluids through the chamber via the first end opening when the force applied by the biasing member is overcome by an opposing force applied to the movable member.
In a further embodiment, a method is provided for controlling fluid flow within a cylinder with a valve device secured to the cylinder. The method comprises securing a valve device to an outlet of the cylinder, where the valve device includes a valve housing with an outlet port to deliver fluid from the cylinder to a fluid flow line, and providing a valve member in the outlet port of the valve device. The valve member includes a passage that is in fluid communication with a central passage of the valve housing, and a movable member that engages with a seat to provide a fluid tight seal for the valve member in a closed position. The movable member is configured to be moved away from the seat so as to open the valve member and permit fluid to flow from the central passage of the valve housing around the movable member and through the outlet port while substantially preventing a backflow of fluids from a location external to the valve housing into the central passage.
The valve devices and corresponding methods are particularly useful for facilitating safe storage, shipping and/or delivery of gaseous and/or liquid fluids in cylinders at sub-atmospheric pressure conditions, such as air-reactive gases that are used in semiconductor manufacturing and processing applications, without the risk of backflow of fluids (e.g., air) into the cylinders. Thus, the valve devices and corresponding methods provide an effective solution to the problem of potential contamination and/or safety concerns associated with the storage and use of such fluids.
The above and still further features and advantages will become apparent upon consideration of the following detailed description of specific embodiments thereof, particularly when taken in conjunction with the accompanying drawings wherein like reference numerals in the figures are utilized to designate like components.
Valve devices are described herein that attach to a cylinder or other fluid supply source and effectively prevent backflow or diffusion of air and/or other fluids from system lines and/or the surrounding environment into the cylinder or fluid supply source. The valve devices can be used for semiconductor and/or other manufacturing processes or applications and can be used for storing, transporting and/or processing any suitable types of fluids. In particular, the valve devices are highly effective in preventing backflow into cylinders containing flammable, pyrophoric, corrosive and/or highly reactive gases stored at any selected pressures (e.g., for SAGS processes), where the compounds can be gaseous, liquid and/or solid and can include, without limitation, compounds such as germanes, methylsilanes, polysilanes such as trisilane, silyl-germanes, silylamines such as trisilylamine, organometallic metal compounds, boron trifluoride, boron trichloride, tungsten hexafluoride, fluorocarbons (e.g., octafluorocyclopentene or C5F8) and other organic or inorganic compounds (e.g., hexane, octane, etc.).
An exemplary valve device that can be connected with a cylinder is schematically depicted in
Each of the valves in valve device 2 can be of any one or more suitable types including, without limitation, diaphragm valves, packed valves, bellows valves, ball valves, gate valves, butterfly valves, and globe valves, and these valves can be manipulated to open or closed positions manually (e.g., by an operator) and/or automatically (e.g., via pneumatic and/or electronic components). Valves 8 and 12 are preferably valves that facilitate the flow of fluid in one direction through the valves as described below.
In an exemplary embodiment, the valve device of
Valve 8 at filling port 6 facilitates the flow of fluid in one direction from a fluid transfer line 16 that connects with the filling port into cylinder 1 (as indicated by the arrow above valve 8 in
The schematic of the valve device set forth in
A shut-off or stop valve is defined within the main body 23 by a movable body 26 that is axially movable within the main body to engage with a seat 28 located at an end of channel 22. The channel seat 28 provides a restricted channel passage to facilitate the formation of a fluid tight seal when movable body 26 engages with the seat. The movable body is further connected to a handle 27 that can be manipulated in a conventional or any other suitable manner to effect movement of the body 26 toward or away from seat 28 (e.g., by rotation of the handle and based upon a threaded engagement of the handle with the main body) in order to close or open the stop valve.
Outlet port 30 extends transversely from channel 22 at the location of the stop valve seat 28 such that, when movable body 26 is displaced or moved away from a sealing engagement with seat 28, the outlet port 30 is in fluid communication with channel 22 and cylinder 1. When the movable body engages with the seat, the stop valve is closed and prevents fluid flow between the cylinder and outlet port. The outlet port is also connectable (e.g., via a threaded connection) to a system fluid line 36 to which fluids from cylinder 1 are to be delivered.
A diaphragm valve 32 is disposed within the outlet port and engages with a narrowed portion or seat 34, which is located within the outlet port between the diaphragm and the stop valve seat 28, so as to form a fluid tight seal with seat 34. The diaphragm valve can be any conventional or other suitable type of diaphragm valve. For example, the diaphragm valve can include a diaphragm that is constructed of a thin and flexible sheet of rubber, plastic or metal material (e.g., stainless steel) and that is secured against the seat in any suitable manner (e.g., via fasteners, a resilient spring, etc.) to achieve the seal. The diaphragm is further movable or flexible to permit a selected degree of flexion or movement of one or more portions of the diaphragm away from the seat so as to release the fluid tight seal and thus open the valve when a threshold pressure differential is achieved in the desired direction across the diaphragm. The diaphragm further moves or flexes back to its original engaging position with the seat when the pressure differential is lower than the threshold value, thus resuming the fluid tight seal and closing the valve.
In the embodiment of
This valve configuration at the outlet port of the valve device is very useful, particularly in applications where a gaseous fluid or a low vapor pressure liquid is stored in the cylinder at very low pressures (e.g., SAGS applications), since the valve prevents fluids at higher pressures from flowing into the cylinder via the outlet port. Basically, diaphragm valve 32 ensures one way flow of fluid from cylinder 1 to process line 36 at all times during operation of the valve device.
Filling port 24 extends transversely from and is in fluid communication with channel 22 at a location between the connection port 21 and the stop valve seat 28. The filling port also includes a diaphragm valve 40 that is similar in configuration to the diaphragm valve disposed in the outlet port. In particular, the diaphragm valve includes a diaphragm (e.g., a thin sheet of rubber, plastic or metal) that is secured against a narrowed portion or seat 41, which is located within filling port 24 between the diaphragm and an inlet of the filling port, so as to form a fluid tight seal to close the valve. The diaphragm is further capable of flexing or moving away from the seat when a suitable force is applied against the diaphragm to move the diaphragm in a direction away from the seat and toward channel 22, such that the fluid tight seal is released to open the valve. Thus, the diaphragm valve is designed to prevent flow of fluid from the cylinder and through the filling port regardless of the fluid pressure within the cylinder. In addition, the diaphragm within the filling port is suitably secured against the seat to prevent fluids that are outside the cylinder (e.g., air), and which are at typical ambient and/or other system pressure levels, from forcing movement or flexure of the diaphragm so as to open valve 40.
Diaphragm valve 40 further includes a rod 42 that is secured to an outer end of the diaphragm and extends toward the inlet of filling port 24. A filling connector 46 connects with filling port 24 in any suitable manner (e.g., via a threaded engagement) to provide a fluid tight seal so as to facilitate filling of cylinder 1 through the filling connector with a fluid provided from a fluid supply source (e.g., another cylinder or a production facility, not shown). Secured at a suitable location within connector 46 is a threaded engaging member 48. The engaging member 48 includes an extension 49 that is configured to engage with rod 42 when the filling connector is securely fastened to the filling port. The contact between engaging member extension 49 and rod 42 forces flexure or movement of the diaphragm away from the seat, which opens diaphragm valve 40 to permit fluid flow through the valve and into the cylinder during filling of the cylinder. The filling connector and/or engaging member further include(s) one or more passages that permit flow of fluid through or around the engaging member during the cylinder filling operation.
In the embodiment of
In operation, cylinder 1 can be filled via filling port 24 of valve device 20 by connecting filling connector 46 with the filling port, which results in an opening of diaphragm valve 40 upon engagement of extension 49 with connector with rod 42 of the valve. The cylinder can be filled with fluid to a desired pressure, followed by removing the connector from the filling port which results in closing of valve 40. As noted above, the fluid pressure within cylinder 1 is incapable of opening valve 40 due to the design of the diaphragm within the valve device.
Upon connection of outlet port 30 of the valve device with system line 36, the stop valve can be opened by manipulation of handle 27 to effect movement of movable body 26 from valve seat 28. Opening of the stop valve facilitates fluid communication between main channel 22 and outlet port 30. As noted above, the diaphragm of diaphragm valve 32 flexes away from seat 34 only when the pressure is greater within the cylinder than the system line and when a suitable pressure differential is achieved. In operations in which the cylinder fluid is at very low pressures (e.g., SAGS operations), a vacuum is applied within fluid line 36 to facilitate movement or flexure of the diaphragm of valve 32 away from seat 34 in order to facilitate fluid flow from cylinder 1 into fluid line 36. Upon removal of the vacuum, the diaphragm flexes back to its original fluid tight engagement with seat 34, thus closing the diaphragm valve.
In the event the pressure level in the outlet port at a location downstream from diaphragm valve 32 becomes greater than the cylinder pressure level (e.g., in situations where a leak within the system line develops, or the stop valve is inadvertently left open or is defective and incapable of forming a seal with seat 28 during periods where the valve line is detached from the system line), the diaphragm remains in sealing contact with seat 34. Such a pressure differential across the diaphragm is further incapable of opening diaphragm valve 32, due to the valve design and configuration, which ensures the prevention of fluid backflow into the cylinder via the outlet port of the valve device.
An alternative embodiment of a diaphragm valve that can be incorporated into a valve device is depicted in
Referring to
Valve housing passage 55 extends from the diaphragm to a main passage of the valve device (e.g., passage 22 of the device of
A pin or rod 58 is connected to an end of diaphragm 52 and extends a selected distance toward and/or within connection member 56. The fluid line connection member 60 includes a tubular member 62 that extends from a partition wall 65 within connection member 60 and through and/or slightly beyond the female threaded end of the connection member, where the outer diameter of the tubular member is smaller than the inner diameter of the connection member. Thus, an annular gap is defined between the tubular member and the internal female threaded wall portions of the fluid line connection member. The terminal end of member 62 includes a disk 64 that is configured to fit within valve housing connection member 56 and engage with rod 58 when the fluid line connection member is connected with the valve housing connection member. The other end of tubular member 62 that connects at wall 65 is in fluid communication with a fluid channel 66 defined on the other side of wall 65 and that leads to or defines a fluid line for a semiconductor manufacturing or other fluid processing system. Tubular member 62 also includes apertures or perforations 63 disposed longitudinally along the member and that extend through the wall thickness of the tubular member to permit fluid communication between the annular gap defined between the fluid line connector and tubular member and the hollow interior of the tubular member.
As can be seen in
The mechanical tension of the diaphragm against the valve seat of valve 50 can be configured to prevent flexion or movement of the diaphragm based upon a selected pressure differential between the cylinder pressure and the ambient pressure and/or pressure within the process line. In other words, the valve is designed to ensure the valve is only opened, under normal operating conditions, when fluid line connection member 60 is connected with valve connection member 56. In addition, the diaphragm can be designed to deform and open the valve at upper threshold pressures within the cylinder so as to prevent over-pressurization of the cylinder.
Thus, whether the fluid within the cylinder is maintained at sub-atmospheric conditions (e.g., for SAGS applications) or at higher pressures, the diaphragm valve can be configured to maintain an effective seal until it is mechanically moved during engagement between connectors 56 and 60. For example, in a SAGS application, a vacuum can be applied within fluid channel 66 once valve 50 is opened so as to withdraw sub-atmospheric fluids from the cylinder into the fluid channel. When the valve is closed (i.e., upon disconnecting member 60 from member 56), air from the ambient environment is prevented from infiltrating the cylinder at valve 50.
Another valve embodiment for use in a valve device (such as the device described in
Valve 70 includes a hollow tubular member 71 secured within a channel of a valve housing (e.g., within the filling and/or outlet ports of the device of
Tubular member 71 includes a coil spring 72 and a movable valve member 74 within the hollow interior of the tubular member. The coil spring 72 extends from a first closed end of the tubular member to bias movable valve member 74 toward a second open end of the tubular member, where the second open end is disposed within the connection member 78 proximate the open end of the valve housing. A plate 76 is secured at the second end of the tubular member and includes an orifice 77 that extends through the plate to provide a fluid flow passage from the hollow interior of tubular member 71 to connection member 78. Tubular member 71 further includes apertures or perforations 73 disposed along and extending through longitudinal or side wall portions of the member, where the perforations provide fluid flow passages between the valve housing channel and the hollow interior of tubular member 71.
The movable valve member is dimensioned to fit snugly within tubular member 71 while permitting easy (e.g., generally frictionless) movement toward or away from plate 76. Movable valve member 74 further includes a protrusion 75 extending from the surface of the movable valve member that faces plate 76. The protrusion 75 has slightly larger dimensions than the orifice dimension and is suitably aligned with orifice 77 so as to block the orifice and provide a fluid tight seal with the plate when the movable valve member is forced against the plate by the bias of coil spring 72. The protrusion can optionally be constructed of a polymer or any other suitable sealing materials and/or include a gasket or O-ring at the contact point with the plate to provide an effective fluid tight seal for a particular gaseous or liquid fluid when biased against the plate. Alternatively, the protrusion and plate can both be constructed of suitable metal materials (e.g., stainless steel) that are designed to provide an effective fluid tight seal for a particular gaseous or liquid fluid.
The fluid line connection member 80 includes a tubular member 82 that extends within and slightly beyond the female threaded end of the connection member, where the outer diameter of the tubular member is smaller than the inner diameter of member 80 so as to define an annular gap between the tubular member and the internal female threaded wall portions of member 80. The other end of tubular member 82 connects with a fluid channel 86 that leads to or defines a fluid line for a semiconductor manufacturing or other fluid processing system. Tubular member 82 also includes apertures or perforations 83 disposed at least along the tubular wall portions that extend slightly beyond the female threaded end of member 80, where the perforations extend through the wall thickness of the tubular member to permit fluid to pass into the tubular member via the perforations.
Tubular member 82 is further configured to have a suitable length and outer diameter dimensions such that, when connection members 78 and 80 are connected to each other, the tubular member extends within member 78 and through orifice 77 to engage with protrusion 75. As can be seen in
Thus, connection of members 78 and 80 results in an opening of valve 70. This permits fluid stored within the cylinder to flow into the channel of the valve housing, through perforations 73 located near the second end of tubular member 71 (e.g., within a distance from the second end at which valve member 74 has been displaced by member 82), through perforations 83 and into member 82. The fluid continues to flow through tubular member 82 into fluid channel 86 for delivery to a selected process. When connection members 78 and 80 are separated from each other, tubular member 82 is removed from engagement with protrusion 75, and the bias of spring 72 forces valve member 74 back toward plate 76. The spring further forces protrusion 75 against the plate at orifice 77 to form a fluid tight seal, thus closing valve 70. The spring tension of coil spring 72 can be selectively adjusted to prevent opening of the valve by ambient pressure levels that surround the cylinder, thus preventing undesirable backflow of fluids (e.g., air) into the cylinder through valve 70. In addition, the valve is designed to prevent any flow of fluid from the cylinder through valve 70 when fluid line connection member 80 is not attached with valve connection member 78.
As noted above, the valve embodiments of
A further embodiment of a valve device is depicted in
A shut-off or stop valve is defined within the main body 101 by a movable body 26 that is axially movable within the main body to engage with a seat 28 located at an end of channel 22. As in the stop valve embodiment of
The second port 102 extends transversely from channel 22 at the location of the stop valve seat 28 such that, when movable body 26 is displaced or moved away from a sealing engagement with seat 28, the second port is in fluid communication with channel 22 and cylinder 1. Port 102 further includes an open end 104 having an externally (i.e., male) threaded configuration and an internally threaded channel 106 disposed within the second port and which communicates with open end 104. The internally threaded channel 106 of port 102 provides a female threaded connector configuration for a corresponding externally or male threaded valve member 110, which is described in further detail below. The externally or male threaded configuration of open end 104 facilitates a fluid tight connection between the valve device and a corresponding female threaded connector for a fluid flow line. The fluid flow line that connects with port 102 can be a filling line for cylinder 1 or a fluid line for delivering fluid from the cylinder to a process. Thus, port 102 serves as both a filling port for cylinder 1 and an outlet port for delivery of fluid from the cylinder to a desired process or application. However, as noted in further detail below, if port 102 is used to fill cylinder 1, valve member 110 must first be removed from the valve device.
Valve member 110 has a generally cylindrical, plug-like configuration that is preferably configured to substantially fit within threaded channel 106 of port 102 when the valve member is installed within the valve device. Referring to
A sealing member 122 (e.g., a gasket) is secured within a first open end of member 110 to provide a fluid tight seal at the first open end. The sealing member can be constructed of any suitable materials (e.g., polymer materials such as plastics or rubber materials, metals such as stainless steel, etc.) that serve to provide an effective seal at the first open end of the valve member and depending upon a particular fluid to be processed by the valve device. As can be seen in
Other valve components disposed within chamber 114 include a movable member 118 and a biasing member 116 (e.g., a coil spring) that is disposed between the movable member and a second open end of the valve member so as to bias the movable member toward sealing member 122. An annular ledge 111 extends radially inward within the hollow interior of valve member 110 at the second end to secure biasing member 116 within chamber 114. A central orifice 113 is further defined at the ledge 111 so as to ensure a fluid flow path exists between chamber 114 and the second open end of the valve member.
The valve member optionally includes a notch 112 at the second open end that is suitably configured to receive a tool that facilitates threaded attachment of the valve member within internally threaded channel 106 of the filling/outlet port of the valve device. The valve member is oriented during assembly such that the first end of the valve member is first inserted within internally threaded channel 106 of the port, and notch 112 is exposed to allow the tool to engage the second end of the valve member. Thus the first end is the inlet of valve member 110, while the second end is the outlet of the valve member. The notch can have any suitable shape to facilitate engagement with any type of tool (e.g., a screwdriver, wrench, etc.). For example, notch 112 can have a generally hexagonal shape to receive a corresponding hexagonal shaped wrench.
The movable member and biasing member disposed within the chamber of the valve member are suitably dimensioned and configured such that the biasing member forces the movable member against a valve seat disposed on a surface of the sealing member, where the forced engagement of the movable member at the valve seat results in a fluid tight relationship that prevents fluid from flowing in either direction through the sealing member (thus preventing fluid from entering the valve member chamber through its first end). As shown in
The movable member can be constructed of any suitable materials (e.g., polymers such as polytetrafluoroethylene commercially available under the trademark TEFLON, metals such as stainless steel, etc.) that provide an effective sealing arrangement between the movable member and the sealing member and depending upon a particular fluid that is being processed by the valve device. In addition, while the movable member is shown in
In operation, valve device 100 is secured to cylinder 1 and, if necessary, the cylinder can be filled with fluid at port 102 of the device. Valve member 110 is secured within the internally threaded channel 106 of valve device 100 (e.g., via a suitable tool) so as to achieve a suitable fluid tight engagement. The valve member can be secured to the valve device either before the valve device is secured to the cylinder (e.g., in applications where the cylinder has already been filled with fluid) or after the valve device has been secured to the cylinder (e.g., in applications where the valve device is also used to fill the cylinder via port 102). The stop valve is then opened (by moving movable body 26 away from valve seat 28) to facilitate fluid communication between cylinder 1 and port 102.
The biasing or spring tension of biasing member 116 is configured to be greater than the cylinder pressure, such that movable member 118 within valve member 110 maintains a fluid tight seal against sealing member 122 (as shown in
When it is desired to cease delivery of fluid from the cylinder, vacuum is no longer applied within the fluid flow line. Biasing member 116 forces movable member 118 back into sealing engagement with sealing member 122, resulting in closing of the valve member once again (as shown in
The one-way valve member described above and depicted in
The valve member is easily removable and securable within a valve port, and this securing operation can be achieved without the requirement of disassembling the valve device from a cylinder. In addition, the other valve embodiments described above can also be configured so as to be easily removable from a cylinder valve housing. As with the other valve embodiments described above, the valve member described in
The effectiveness of the valve member described above is demonstrated in the following example. The valve member of
Another embodiment of a plug-like valve member that can be secured within a channel of an outlet port (e.g., port 102 of valve device 100 as depicted in
Valve member 210 includes a channel extending axially between inlet and outlet ends of the valve member, where the channel includes a chamber 214 that extends from the inlet end of the valve member a selected distance within the valve member. Chamber 214 is suitably dimensioned to receive valve components that operate in a manner described below to open and close the valve member.
In addition, the axially extending channel includes a notch 212 extending from the outlet end of the valve member to chamber 214, where the notch 212 extends to chamber 214 and is slightly larger in transverse cross-sectional dimension than the portion of chamber 214 that is adjacent the notch. The notch 212 is suitably configured to receive a tool that facilitates threaded attachment of the valve member within the internally threaded channel of the filling/outlet port of the valve device. The valve member is oriented during assembly such that the inlet end of the valve member is first inserted within the internally threaded channel of the port, and notch 212 is exposed to allow the tool to engage the outlet end of the valve member. The notch can have any suitable shape (e.g., hexagonal) to facilitate engagement with any type of tool (e.g., a screwdriver, wrench, etc.).
An insert member 222 is secured within the inlet end of valve member 210 to provide a fluid tight seal at the inlet end. The insert member can be constructed of any suitable materials (e.g., polymer materials such as plastics or rubber materials, metals such as stainless steel, etc.) that serve to provide an effective fluid tight seal at the inlet end of the valve member and depending upon a particular fluid to be processed by the valve device. Insert member 222 has a generally T-shaped cross-sectional configuration, with a first portion 223 of the insert member (i.e., the top of portion of the “T”) being secured against the open inlet end of the valve member. A second portion 224 of the insert member is securely fit within chamber 214 of the valve member and engages in a fluid tight seal with interior wall surface portions of the valve member. The insert member configuration provides significant surface area contact between the sealing member and inlet end portions of valve member 110 to ensure a fluid tight seal is maintained. A third portion 225 of the insert member extends from and has a transverse cross-sectional dimension that is smaller than that of second portion 224. The third portion is suitably designed to engage with a valve sealing member 230 described below.
A passage or channel 226 extends axially through insert member 222. Optionally, channel 226 can include a porous filter media or material having a suitable pore size so as to provide filtration of fluids passing through the channel during operation of the valve member. The channel 226 communicates with chamber 214 so as to permit fluid to flow through the insert member from the inlet of valve member 210 and into the chamber when valve sealing member 230 is in an open position as described below.
Sealing member 230 is constructed of a suitable elastomeric material. Any suitable elastomeric material can be used to form the sealing member that is compatible with the fluid to be processed including, without limitation, materials such as fluorosilicone, fluorocarbon, and ethylene propylene. The sealing member is hollow and includes a channel 232 extending axially through and between an inlet end and an outlet end of member 230. The inlet end of the sealing member is secured around third portion 225 of the insert member to form a fluid tight seal at such engagement. The outlet end of sealing member 230 is formed by flaps or lip portions of the sealing member that contact each other to form a sealing slit at the outlet end. As can be seen from
When a valve device is secured to a fluid flow line (e.g., in a manner as described above for the valve device of
However, when the fluid pressure within the cylinder to which the valve device is attached is greater than the fluid flow line pressure or the pressure downstream from sealing member 230 (e.g., when a vacuum is applied within the fluid flow line to establish a suitable pressure differential across the valve member), the fluid pressure within the cylinder forces the elastomeric “duck bill” lip portions to flex and separate from each other as shown in
An example showing the effectiveness valve member of
Having described novel valve devices and corresponding methods for containing and preventing backflow of fluids, it is believed that other modifications, variations and changes will be suggested to those skilled in the art in view of the teachings set forth herein. It is therefore to be understood that all such variations, modifications and changes are believed to fall within the scope as defined by the appended claims.
This application claims priority from U.S. Provisional Patent Application Ser. No. 60/686,343, entitled “Supply Containment System for Sub-atmospheric Gases and Low Vapor Pressure Liquids,” and filed Jun. 1, 2005, and from U.S. Provisional Patent Application Ser. No. 60/761,505, entitled “A Cylinder Device to Prevent Back-Flow,” and filed Jan. 24, 2006. The disclosures of these provisional patent applications are incorporated herein by reference in their entireties.
Number | Date | Country | |
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60686343 | Jun 2005 | US | |
60761505 | Jan 2006 | US |