Patent Description:
Any fluid delivery apparatus intended for manipulating process materials within semiconductor manufacturing equipment usually requires attention to maintaining high purity of the delivered reactants. Mechanical shafts sliding or rotating within a packing type of seal arrangement are known to often cause detectable particulate contamination of high purity process materials. Fluids that are radioactive, poisonous, pyrophoric, or otherwise dangerous, may also be thought less safe when handled in an apparatus having packing type seals. In response to these concerns, designers developed valves whereby the actuator sealing is done by a flexible, usually metallic, element that separates the valve chamber from an external environment surrounding the valve. <CIT>, is one example of a valve with a manual actuator using a metallic bellows for sealing the controlled fluid from the surrounding environment. Later experience revealed the relatively large surface area associated with the pleats of a bellows may be problematic with regard to internal sources of contamination in high purity fluid delivery systems. <CIT> and <CIT>, are two examples of valves using diaphragms, having fluid exposed surface area somewhat lower than bellows, for sealing and are also shown with manual actuators. A variety of actuator types, including pneumatic and electric, may be used with both bellows and diaphragm sealed valves, as is well known. The desire to absolutely minimize all possible moisture absorption sites within a high purity fluid delivery pathway has led to valve designs absent any internal polymeric material, and thus designs dealing with metal to metal contact between a moveable control element and a fluid conduit opening within the valve chamber. <CIT>, and <CIT>are two examples of valves having metal diaphragms directly contacting a toroidal bead valve seat surrounding a fluid conduit opening within a valve body.

<CIT> describes a device for controlling the passage of a fluid, wherein the device comprises an element having a passage and a closure member for this passage.

<CIT> describes a multilevel control nozzle for discharging steam water, wherein the multilevel control nozzle consists of a lower housing part and a housing upper part, and wherein both housing parts form the wall of a eddy/swirling space, and wherein the multi-level control nozzle consists of two expansion stages.

<CIT> describes flow control valves which are pressure operated in an opening direction and is concerned more particularly with that type which is vertically reciprocable between opened and closed positions.

<CIT> describes a homogenization valve for use in homogenizing emulsion explosives.

<CIT> describes a valve having a sealing element, and a seat element with a sealing seat having a surface with a channel-shaped contour with multiple risings and multiple recesses.

<CIT> describes a flow control device having a control member that forms a seal with another part of the flow control device, such as a body portion or a seat area.

In consideration of the foregoing applicant has developed a high conductance valve suited to fluid delivery that is comprised of a flat, typically non-circular, orifice ridge adjacent to which a control plate having a planar control surface is proximally positioned to adjust the valve effective opening area and thereby the conductance of the valve. The length of the non-circular orifice ridge periphery is substantially greater than the circumference of a similarly sized circular orifice and therefore the realized effective opening area is also substantially greater despite having a similar footprint. Additionally, a plurality of orifice ridges may be used within a single valve to obtain the benefits of the total orifice ridge periphery length being greater than the circumference of a similarly sized circular orifice.

In a first embodiment a non-circular orifice ridge has a kidney-like shape and a control plate may be positioned by any suitable actuator arrangement. In a second embodiment a non-circular orifice ridge has a kidney-like shape and a control plate is biased by a disk spring so as to form a check valve. In another embodiment a non-circular orifice ridge includes a plurality of petal-like loops and may be used for any of the preceding functions in addition to being suitable for flow division purposes. In another embodiment a portion of a valve chamber outer cavity partially surrounded by a large kidney-like orifice ridge shape is filled with a second similar and smaller kidney-like orifice ridge also in fluid communication with the same fluid conduit that feeds fluid to the large kidney-like orifice ridge. In another embodiment a plurality of non-circular orifice ridge shapes are in parallel fluid communication with a common valve inlet region. In another embodiment a first orifice ridge completely surrounds a second orifice ridge and creates a valve chamber inner cavity which admits flow to a valve chamber outer cavity comprised of two portions.

Preferred examples are defined in the dependent claims.

Still other aspects, embodiments, and advantages of these example aspects and embodiments, are discussed in detail below. Moreover, it is to be understood that both the foregoing information and the following detailed description are merely illustrative examples of various aspects and embodiments, and are intended to provide an overview or framework for understanding the nature and character of the claimed aspects and embodiments. Embodiments disclosed herein may be combined with other embodiments, and references to "an embodiment," "an example," "some embodiments," "some examples," "an alternate embodiment," "various embodiments," "one embodiment," "at least one embodiment," "this and other embodiments," "certain embodiments," or the like are not necessarily mutually exclusive and are intended to indicate that a particular feature, structure, or characteristic described may be included in at least one embodiment. The appearances of such terms herein are not necessarily all referring to the same embodiment.

This invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the drawings. Also, the phrasing and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of directional adjectives "inner, "outer," "upper," "lower," and like terms, are meant to assist with understanding relative relationships among design elements and should not be construed as meaning an absolute direction in space nor regarded as limiting.

A representative example of a typical usual design valve <NUM> for use in a high purity fluid delivery application is illustrated in <FIG>. The usual design valve comprises a body <NUM>, an inlet conduit <NUM>, an outlet conduit <NUM>, both of which communicate fluid to a valve chamber <NUM>, a chamber sealing diaphragm <NUM>, and a control element <NUM> moveable by deflection of the diaphragm <NUM>. The manner of controlling fluid flow may be further understood by considering an orifice <NUM>, through which the inlet conduit <NUM> discharges fluid into the valve chamber <NUM>, and an orifice ridge <NUM> surrounding said orifice <NUM>, thereby defining a small clearance control gap with respect to the control element <NUM> which may be changeably positioned by force applied to a control shaft <NUM>, and through which control gap fluid may flow. It should be appreciated the illustration of <FIG> shows the usual design valve in a fully closed not flowing fluid condition and therefore no control gap, as such, is to be revealed in the illustrated configuration.

One method of using an actuator with the usual design valve <NUM> is shown in <FIG> which includes an interlace lifting mechanism <NUM>, as disclosed in <CIT> and published as <CIT>, coupling a piezoelectric actuation stack <NUM> to the control shaft <NUM>. Application of an appropriate voltage to the piezoelectric stack <NUM> will cause stack axial extension and through the interlace lifting mechanism <NUM> thereby cause a motion which lifts the control element <NUM> away from the orifice ridge <NUM> allowing fluid to flow between the inlet conduit <NUM> and the outlet conduit <NUM>. A skillfully used piezoelectric actuator has an overall extension ability typically limited to about fifty microns (millionths of a meter) corresponding to approximately two thousandths of an inch. It is generally understood that a valve comprised of an orifice covered by a flat control element will, upon opening, have a flow conductance (or its inverse, flow resistance) related to an effective opening area simply computed as an area defined by the periphery length (circumference) of the orifice multiplied by the control gap between the flat control element and said orifice periphery. Considering a circular orifice of diameter "D", a designer will appreciate any valve control gap "G" greater than "D/<NUM>" will have little additional conductance effect since the open area of the orifice itself will then be smaller than the corresponding effective opening area. <MAT> When G>D/<NUM>, then the flow resistance of the orifice will dominate the flow resistance of the effective opening area.

Designers may further appreciate that any valve design not able to move the control element away from a circular orifice at least one quarter of the orifice diameter will not achieve the maximum flow conductance otherwise feasible in the particular valve design. Control element translation is often substantially limited by the necessity of deforming metallic parts only in purely elastic strain. Many combinations of valve chamber sealing methods and control element translations have maximum valve flow conductance depend mostly upon the length of the orifice periphery rather than the cross section of the fluid conduits. A known approach to this design problem is to provide a circular orifice diameter substantially greater than the diameter of the associated fluid conduits. <CIT>, shows a check valve having limited control element translation and a circular orifice diameter approximately three times the diameter of the inlet and outlet fluid passages. <CIT>, shows a diaphragm sealed valve with piezoelectric actuator and a circular orifice described in the specification as "an enlarged bell mouth annular rimmed valve port that is larger than the fluid passage.

Applicant has devised a valve design which addresses many of the forgoing problems as illustrated in <FIG>, <FIG>, <FIG>, and <FIG>. An exemplary valve design comprises a valve body <NUM>, a first fluid conduit <NUM> (typically an inlet), a second fluid conduit <NUM> (typically an outlet), both of which communicate fluid to a valve chamber <NUM>, a valve housing <NUM> which includes a valve chamber sealing diaphragm <NUM>, and a control element <NUM> moveable by deflection of the valve chamber sealing diaphragm <NUM>. A shank <NUM> may project from the sealing diaphragm <NUM> into the valve chamber <NUM> approximately centered on the axis of the control element <NUM>. A control plate <NUM> with a central thru-hole having a recessed opening <NUM> may be affixed to the shank <NUM> by deforming the end of the shank <NUM> within the recessed opening <NUM>. Actuator force applied to the control element <NUM> will move the control plate <NUM> to provide valve function as further explained below.

Designers of valves for high purity applications generally are aware of many different approaches to providing a leak tight valve chamber sealing diaphragm. In <CIT>, a diaphragm comprised of three sheet metal discs is peripherally clamped between stepped structures in a valve body and a valve bonnet. In <CIT>, a single layer sheet metal diaphragm is welded to a portion of a valve assembly. In <CIT>, a diaphragm is statically sealed against a valve body by a clamping member forcing the diaphragm against a toroidal-shaped projection on the valve body. The instant invention illustrates a sealing diaphragm <NUM> machined as an integral element of a valve housing <NUM>. For convenience all Figures in this disclosure show a similar integrally machined valve sealing diaphragm, but it should be appreciated other combinations of diaphragm and valve housing, or valve body, elements can be used with the present invention and the integral diaphragm should not be construed as limiting.

Instead of a circular orifice, applicant has devised a non-circular orifice ridge <NUM> structure separating the valve chamber <NUM> into an inner cavity <NUM> and an outer cavity <NUM>. The orifice ridge <NUM> may be formed as a closed non-circular circuit comprising a plurality of interconnected segments surrounding an inner fluid conduit opening <NUM> in a path of changing curvature. According to various aspects, the plurality of interconnected segments includes at least one segment that curves away from the fluid conduit opening. According to other aspects, the plurality of segments may further include at least one segment that curves toward the fluid conduit opening. According to other aspects, at least one segment that curves away from the fluid conduit opening is adjacent to a segment that curves toward the fluid conduit opening. As used herein, a curved segment includes any segment in which all points along the curved segment have the same radius of curvature or at least one inflection point. For example, referring to <FIG>, the orifice ridge structure is shaped like a kidney, and includes four curved segments, A, B, C, and D. In certain instances, at least one segment may be linear, i.e., straight. The exemplary orifice ridge <NUM> shape is considered to be like a kidney shape. Put another way, the kidney shape of the orifice ridge <NUM> is characterized as having three segments that curve toward the inner fluid conduit opening <NUM> and one segment that curves away from the inner fluid conduit opening <NUM>. For instance, referring back to <FIG>, segments A, B, and C all curve toward the fluid conduit opening and segment D curves away from the fluid conduit opening. Designers will appreciate the illustrated exemplary orifice ridge <NUM> is comprised of interconnected curved segments forming the entire shape with no straight segments anywhere. The inner fluid conduit opening <NUM> provides fluid communication between the inner cavity <NUM> and the first fluid conduit <NUM>. An outer fluid conduit opening <NUM> may provide fluid communication between the outer cavity <NUM> and the second fluid conduit <NUM>. The outer fluid conduit opening <NUM> is disposed external to the orifice ridge <NUM>.

The parts comprising said valve may be constructed from materials chosen for desired chemical inertness relative to the fluids to be handled and may include, for example, stainless steels, Monel® metals, titanium alloys, Hastelloy® nickel alloys, Elgiloy® cobalt alloy, copper alloys, aluminum alloys, or polymers such as Teflon®, Kel-F®, Vespel®, Kynar®, and combinations of metals and polymers either separate or together. For example, a type <NUM> stainless steel valve body <NUM> may be used with a Hastelloy® nickel alloy control plate <NUM>. The valve body <NUM> with the orifice ridge <NUM> can be made by typical manufacturing processes such as milling, or casting, or injection molding, or recently developed additive manufacturing processes such as laser sintering (3D printing), for example. The valve body regions contacted by the controlled fluid may be subjected to additional processes, such as polishing and passivation, as is known in the art of high-purity fluid delivery.

The potential flow restricting effects of the fluid conduit openings <NUM>, <NUM> may be lessened by enlarging the openings relative to the cross-sectional area of the corresponding fluid conduits <NUM>, <NUM>. Exemplary beneficial opening modifications may comprise an arcuate slot as illustrated in the inner fluid conduit opening <NUM>, or a radial slot <NUM> as illustrated in the outer fluid conduit opening <NUM>, or blended constructions of these and other shaping such as flaring and beveling. Skilled designers will further appreciate a plurality of fluid conduit openings may be formed within the inner cavity <NUM>, or formed within the outer cavity <NUM>, or both, so as to provide fluid communication between a cavity and a corresponding plurality of fluid conduits formed in a valve body (see for example, Fig. <NUM> & Fig. <NUM> of <CIT>).

The upper topmost portion of the orifice ridge <NUM> may be made very flat, planar and smooth by lapping, or similar manufacturing process, and that surface is herein referred to as a contact track <NUM> of the orifice ridge <NUM>. A control plate <NUM> having suitable likewise substantially planar control surface <NUM> of sufficient extent (typically a diameter) may rest against (make contact with) the entire contact track <NUM> to effectively close off all flow through the valve body <NUM>. The valve effective opening area which is computed as an area defined by the periphery length of the orifice ridge <NUM> (the planar length of the contact track <NUM>) multiplied by any control gap between the planar control surface <NUM> and the contact track <NUM>, may be advantageously enlarged by the disclosed design. The length of the periphery of the non-circular orifice ridge <NUM> may be made substantially greater than the circumference of a simple circular orifice occupying the same space by including curved segments bending both toward and away from the inner fluid conduit opening <NUM>.

A reasonable baseline comparison of the disclosed valve design (see <FIG>) may be figured in the context of a circular valve chamber sealing diaphragm <NUM>. The kidney-like orifice ridge <NUM> shape shown in <FIG>, <FIG>, and <FIG> provides approximately <NUM>% more periphery length than a circular orifice of identical maximum dimension (diameter). <MAT> If the comparison circular orifice surrounds an area equal to the enclosed planar area of the inner cavity <NUM>, then the increased valve effective opening area increase is a more dramatic <NUM>%. <MAT> While the valve effective opening area ( gap*periphery = opening area ) has been substantially increased by use of the non-circular closed circuit shape for the orifice ridge <NUM>, the planar area of the space actually enclosed as the inner cavity <NUM> is substantially less (approximately <NUM>% less) than would be the case of a similarly sized circular orifice. <MAT> The reduced planar area corresponding to the inner cavity <NUM> beneficially reduces the force needed to close the control plate <NUM> against the orifice ridge <NUM> when resisting pressurized fluid flowing from the first fluid conduit <NUM> toward the second fluid conduit <NUM>. In this exemplary design the orifice ridge is approximately <NUM>" (<NUM>) high, and the contact track is approximately <NUM>" (<NUM>) wide, thus mimicking the structure of the design valve illustrated in Figa. <NUM> and 1A.

Another exemplary valve design illustrated in <FIG>, <FIG>, & <FIG> comprises a valve body <NUM>, a first fluid conduit <NUM> (an inlet), a second fluid conduit <NUM> (an outlet), both of which conduits communicate fluid to a valve chamber <NUM>, a cup-shaped valve chamber sealing lid <NUM>, also referred to herein as a valve chamber sealing cap, and a control plate <NUM> moveable by deflection of a disk spring <NUM>. The control plate <NUM> may be formed as a circular plate having a planar control surface <NUM>. Instead of a circular orifice, this embodiment features a non-circular orifice ridge <NUM> structure separating the valve chamber <NUM> into an inner cavity <NUM> and an outer cavity <NUM>. The orifice ridge <NUM> may be formed as a closed non-circular circuit comprising a plurality of interconnected segments surrounding an inner fluid conduit opening <NUM> in a path of changing curvature. Similar to the orifice ridge discussed above in reference to <FIG>, <FIG>, <FIG>, and <FIG>, the plurality of interconnected segments may include at least one segment that curves away from the fluid conduit opening, and in certain instances may include at least one segment that curves toward the fluid conduit opening, and in other instances a segment that curves away from the fluid conduit opening may be adjacent to a segment that curves toward the fluid conduit opening. As discussed above with reference to the orifice ridge <NUM>, the kidney shape of the orifice ridge <NUM> includes three segments that curve toward the fluid conduit opening and one segment that curves away from the fluid conduit opening. The inner fluid conduit opening <NUM> provides fluid communication between the inner cavity <NUM> and the first fluid conduit <NUM>. An outer fluid conduit opening <NUM> provides fluid communication between the outer cavity <NUM> and the second fluid conduit <NUM>. The outer fluid conduit opening <NUM> is disposed external to the orifice ridge <NUM>. The parts comprising this valve may also be constructed from materials chosen for desired chemical inertness relative to the fluids to be handled and may include combinations of metals and polymers either separate or together. For example, a type <NUM> stainless steel valve body <NUM> may be used with a Kel-F® polymer control plate <NUM> and an Elgiloy® cobalt alloy disk spring <NUM>, or all three items may be <NUM> series stainless steels.

The upper topmost portion of the orifice ridge <NUM> may be made very flat, planar and smooth by lapping, or similar manufacturing process, and that surface is herein referred to as a contact track <NUM> of the orifice ridge <NUM>. A surrounding cap alignment ridge <NUM> may be prepared at the same time as the orifice ridge <NUM>. The circular control plate <NUM> is of sufficient extent (typically a diameter) and having suitable likewise planar control surface <NUM> such that it may rest against (make contact with) the entire contact track <NUM> to effectively close off all flow through the valve body <NUM>. A central hole <NUM> through the control plate <NUM> may be provided to enhance fluid communication from that portion of the valve chamber <NUM> which is adjacent the sealing lid inner top <NUM> into the outer cavity <NUM>. The control plate <NUM> is radially positioned and axially positioned by a disk spring <NUM> of known design having multiple arcuate arms <NUM>, <NUM>, <NUM> defined by slots <NUM>, <NUM>, <NUM> in the disk spring <NUM>. The disk spring <NUM> may be made of material similar to that chosen for a sealing diaphragm <NUM> in the valve configuration discussed above in reference to <FIG>, <FIG>, <FIG>, and <FIG>. The control plate <NUM> may be attached to the disk spring <NUM> by welding, or other suitable process (such as an adhesive or staking) depending upon chosen materials, and may be axially located by a spacer ring <NUM>. Other suitable methods of axial location, such as steps, counterbores, and such, are well known to designers. A step <NUM> is provided around the inner periphery of the cup-shaped sealing lid <NUM> to space the disk spring <NUM> away from the sealing lid inner top <NUM>. The combination of spacer ring <NUM> in conjunction with the step <NUM> and alignment ridge <NUM> allows a single circumferential weld to hermetically attach the valve chamber sealing cap <NUM> to the valve body <NUM> while simultaneously positioning the control plate <NUM> for correct valve function.

In the absence of sufficient fluid pressure (the cracking pressure) within the inlet fluid conduit <NUM>, the axial force of the disk spring <NUM> will hold the control surface <NUM> of the control plate <NUM> tightly against the contact track <NUM> of the orifice ridge <NUM>, and thereby prevent fluid flow. If fluid pressure within the inlet conduit <NUM> is sufficiently higher than within the outlet conduit <NUM>, then the control plate <NUM> will be pushed away from the contact track <NUM> of the orifice ridge <NUM> and fluid may flow out of the inner cavity <NUM> and into the outer cavity <NUM> and thereby through the valve body <NUM>. In the event the pressure differential is reversed and the pressure within the outlet conduit <NUM> is greater than within the inlet conduit <NUM>, then the control plate <NUM> will be pushed against the orifice ridge <NUM> and fluid flow will be blocked. Consequently this embodiment may be considered to be a check valve having the purpose of constraining fluid flow to only a preferred direction.

The potential flow restricting effects of the fluid conduit openings <NUM>, <NUM> may be lessened by enlarging the openings relative to the cross-sectional area of the corresponding fluid conduits <NUM>, <NUM>. Exemplary beneficial opening modifications may comprise a blending and flaring as provided by a hemispherical mouth <NUM>. Skilled designers will further appreciate a plurality of fluid conduit openings may be formed within the inner cavity, or formed within the outer cavity, or both, so as to provide fluid communication between a cavity and a corresponding plurality of fluid conduits formed in a valve body (see for example, Fig. <NUM> & Fig. <NUM> of <CIT>); however, in the surface mount style check valve shown in <FIG> only a single inlet conduit <NUM> and a single outlet conduit <NUM> are used.

The valve effective opening area which is computed as an area defined by the periphery length of the orifice ridge <NUM> (the planar length of the contact track <NUM>) multiplied by any control gap between the planar control surface <NUM> and the contact track <NUM>, may be advantageously enlarged by the disclosed design. The length of the periphery of the non-circular orifice ridge <NUM> may be made substantially greater than the circumference of a simple circular orifice occupying a similar space by including curved segments bending both toward and away from the inner fluid conduit opening <NUM>. The superiority of the instant high-conductance check valve design is made apparent by considering the previous Equation_2 and Equation_3, because the same orifice ridge <NUM>, <NUM> shape may be used in both valves. It should be further appreciated that the valve body <NUM> is intended for use in surface mount fluid delivery systems, wherein fluid handling components are removably attached to flow substrates containing fluid pathway conduits, and therefore the useable size and footprint of components is limited.

Yet another exemplary valve design is illustrated in <FIG>, <FIG> comprises a valve body <NUM>, a first fluid conduit <NUM> (typically an inlet), and a second fluid conduit <NUM> (typically an outlet), both of which communicate fluid to a valve chamber (not shown). Details of suitable, but not shown, sealing diaphragms, control elements, and actuators may be readily appreciated from other embodiments described herein. It should also be noted that this embodiment illustrates how the disclosed valve design may alternatively be used with tubular conduit connections <NUM>, <NUM> instead of being a surface mount type component in a high purity fluid delivery apparatus. Instead of a circular orifice, applicant has devised a non-circular petal-like orifice ridge <NUM> structure separating the valve chamber into an inner cavity <NUM> and an outer cavity <NUM>. The orifice ridge <NUM> may be formed as a closed non-circular circuit comprising a plurality of interconnected segments surrounding an inner fluid conduit opening <NUM> in a path of changing curvature. According to certain aspects, the plurality of interconnected segments that form the orifice ridge <NUM> may include at least one segment that curves away from the fluid conduit opening and at least one segment that curves toward the fluid conduit opening. According to a further aspect, at least one segment that curves away from the fluid conduit opening is adjacent to at least one segment that curves toward the fluid conduit opening. The exemplary orifice ridge <NUM> shape may be considered like petals of a flower in so far as said shape includes an equal number of segments that curve toward and away from the inner fluid conduit opening <NUM>. The inner fluid conduit opening <NUM> provides fluid communication between the inner cavity <NUM> and the first fluid conduit <NUM>. An outer fluid conduit opening <NUM> may provide fluid communication between the outer cavity <NUM> and the second fluid conduit <NUM>. The outer fluid conduit opening <NUM> may be disposed external to the orifice ridge <NUM>. The parts comprising said valve may be constructed from materials chosen for desired chemical inertness relative to the fluids to be handled and may include combinations of metals and polymers either separate or together. For example, a type <NUM> stainless steel valve body <NUM> may be used with a Kel-F® polymer control plate (not shown) and an Elgiloy® cobalt alloy sealing diaphragm (also not shown). Skilled designers will further appreciate a plurality of fluid conduit openings may be formed within the inner cavity <NUM>, or formed within the outer cavity <NUM>, or both, so as to provide fluid communication between a cavity and a corresponding plurality of fluid conduits formed in a valve body (see for example, Fig. <NUM> & Fig. <NUM> of <CIT>), especially for purposes of providing a flow division functionality.

The upper topmost portion of the orifice ridge <NUM> may be made very flat, planar and smooth by lapping, or similar manufacturing process, and that surface is herein referred to as a contact track <NUM> of the orifice ridge <NUM>. A control plate (not shown) having suitable likewise planar control surface (not shown) of sufficient extent (typically a diameter) may rest against (make contact with) the entire contact track <NUM> to effectively close off all flow through the valve body <NUM>. The valve effective opening area, which is computed as an area defined by the periphery length of the orifice ridge <NUM> (the planar length of the contact track <NUM>) multiplied by any control gap between the planar control surface <NUM> and the contact track <NUM>, may be advantageously enlarged by the disclosed design. The length of the non-circular petal-like orifice ridge <NUM> periphery may be made substantially greater than the circumference of a simple circular orifice occupying similar space by including curved segments bending both inwardly and outwardly around the inner fluid conduit opening <NUM>, thereby forming the described petal-like loops. The perimeter of the exemplary design having three petal-like loops is about <NUM>% greater than a round orifice enclosing an identical area. Skilled designers will appreciate that greater than or less than three loops may also be constructed particularly when considering flow dividing valve structures.

Another exemplary valve design is illustrated in <FIG>, <FIG>, and <FIG> comprises a valve body <NUM>, a first fluid conduit <NUM> (typically an inlet), a second fluid conduit <NUM> (typically an outlet), both of which conduits communicate fluid to a valve chamber <NUM>, a valve housing <NUM> which includes a valve chamber sealing diaphragm <NUM>, and a control element <NUM> moveable by deflection of the valve chamber sealing diaphragm <NUM>. A shank <NUM> may project from the sealing diaphragm <NUM> into the valve chamber <NUM> approximately centered on the axis of the control element <NUM>. A control plate <NUM> with a central thru-hole having a recessed opening <NUM> may be affixed to the shank <NUM> by deforming the end of the shank <NUM> within the recessed opening <NUM>. Actuator force applied to the control element <NUM> will move the control plate <NUM> to provide valve function as further explained below. A leak test groove <NUM> may be provided in the face of the valve body <NUM> to assist testing integrity of the seal <NUM> between the valve body <NUM> and the valve housing <NUM> which includes the diaphragm <NUM>.

Instead of a circular orifice, applicant has devised a first non-circular orifice ridge <NUM> structure separating a first inner cavity <NUM> from an outer cavity <NUM> of the valve chamber <NUM>. The first orifice ridge <NUM> may be formed as a closed non-circular circuit comprising a plurality of interconnected segments surrounding a first inner fluid conduit opening <NUM> in a path of changing curvature. Similar to the orifice ridge discussed above in reference to <FIG>, <FIG>, <FIG>, <FIG> and <FIG>, <FIG>, and <FIG>, the plurality of interconnected segments may include at least one segment that curves away from the fluid conduit opening, and in certain instances may include at least one segment that curves toward the fluid conduit opening, and in other instances the segment that curves away from the fluid conduit opening is adjacent to the segment that curves toward the fluid conduit opening. As discussed above with reference to the orifice ridges <NUM> and <NUM>, the kidney shape of the first orifice ridge <NUM> includes three segments that curve toward the fluid conduit opening and one segment that curves away from the fluid conduit opening. In this exemplary valve design, the first kidney-like orifice ridge <NUM> structure at least partially surrounds a second similar and smaller kidney-like second orifice ridge <NUM> structure. This configuration allows a second inner cavity <NUM> to be separated from the outer cavity <NUM>. Thus, the second orifice ridge <NUM> is at least partially surrounded by the first orifice ridge <NUM>. Designers will appreciate that any closed circuit shape may be implemented for the partially surrounded smaller second orifice ridge <NUM>, including circular or non-circular closed circuit shapes, just as the closed circuit of the first orifice ridge <NUM> may be circular in shape and the closed circuit of the second orifice ridge <NUM> may be non-circular in shape. The illustrated kidney-like example comprises a plurality of interconnected curved segments surrounding a second inner fluid conduit opening <NUM>. The valve body <NUM> with the orifice ridges <NUM>, <NUM> can be made by typical manufacturing processes such as milling, or casting, or injection molding, or recently developed additive manufacturing processes such as laser sintering (3D printing), for example. The valve body regions contacted by the controlled fluid may be subjected to additional processes, such as polishing and passivation, as is known in the art of high-purity fluid delivery.

The first inner fluid conduit opening <NUM> provides fluid communication between the first inner cavity <NUM> and the first fluid conduit <NUM>. The second inner fluid conduit opening <NUM> may provide fluid communication between the second inner cavity <NUM> and the first fluid conduit <NUM> (as illustrated) or a different fluid conduit (described in further detail below with respect to <FIG>, <FIG>, <FIG>) according to the designer's intent (e.g. flow splitting versus high conductance). An outer fluid conduit opening <NUM> may provide fluid communication between the outer cavity <NUM> and the second fluid conduit <NUM>. The outer fluid conduit opening <NUM> is disposed external to the first orifice ridge <NUM> and the second orifice ridge <NUM>. The parts comprising said valve may be constructed from materials chosen for desired chemical inertness relative to the fluids to be handled and may include, for example, stainless steels, Monel® metals, titanium alloys, Hastelloy® nickel alloys, Elgiloy® cobalt alloy, copper alloys, aluminum alloys, or polymers such as Teflon®, Kel-F®, Vespel®, Kynar®, and combinations of metals and polymers either separate or together. For example, a type <NUM> stainless steel valve body <NUM> may be used with a Hastelloy® nickel alloy control plate <NUM>.

The potential flow restricting effects of the fluid conduit openings <NUM>, <NUM>, <NUM> may be lessened by enlarging the openings relative to the cross-sectional area of the corresponding fluid conduits <NUM>, <NUM>. Exemplary beneficial opening modifications may comprise an arcuate slot as illustrated in the inner fluid conduit openings <NUM>, <NUM> or a blended construction of other shaping such as flaring and beveling as illustrated at the outer fluid conduit opening <NUM>. The upper topmost portion of the first and second orifice ridges <NUM>, <NUM> may be made very flat planar and smooth by lapping, or similar manufacturing process, and those coplanar surfaces are herein referred to as contact tracks <NUM>, <NUM> of the first and second orifice ridges <NUM>, <NUM>. A control plate <NUM> having suitable likewise substantially planar control surface <NUM> of sufficient extent (typically a diameter) may rest against (make contact with) the entirety of both contact tracks <NUM>, <NUM> to effectively close off all flow through the valve body <NUM>. The valve effective opening area, which is computed as an area defined by the periphery length of the orifice ridges <NUM>, <NUM> in fluid communication with the first fluid conduit <NUM> (the planar length of the contact tracks <NUM>, <NUM>) multiplied by any control gap between the planar control surface <NUM> and the contact tracks <NUM>, <NUM>, may be advantageously enlarged by the disclosed design. The length of the peripheries of the non-circular orifice ridges <NUM>, <NUM> may be made substantially greater than the circumference of a simple circular orifice occupying the same space by including curved segments bending both away and toward the inner fluid conduit openings <NUM>, <NUM> and nesting multiple orifice ridge shapes. Described another way, the second orifice ridge <NUM> may be spaced apart from and at least partially surrounded by the first orifice ridge <NUM>. According to other embodiments, i.e., <FIG>, <FIG>, <FIG>, the second orifice ridge may be completely surrounded by the first orifice ridge.

Another exemplary valve design illustrated in <FIG>, <FIG>, and <FIG> comprises a valve body <NUM>, a flow collection region <NUM> (typically an inlet), a first fluid conduit <NUM> in fluid communication with the flow collection region <NUM>, a second fluid conduit <NUM> in fluid communication with the flow collection region <NUM>, a third fluid conduit <NUM> (typically an outlet), all of which communicate fluid to a valve chamber <NUM>, a valve housing <NUM> which includes a valve chamber sealing diaphragm <NUM>, and a control element <NUM> moveable by deflection of the valve chamber sealing diaphragm <NUM>. A shank <NUM> may project from the sealing diaphragm <NUM> into the valve chamber <NUM> approximately centered on the axis of the control element <NUM>. A control plate <NUM> with a central thru-hole having a recessed opening <NUM> may be affixed to the shank <NUM> by deforming the end of the shank <NUM> within the recessed opening <NUM>. It should be understood the cross section of <FIG> is through the shank <NUM> and reveals the recessed opening <NUM>, while the cross section of <FIG> is offset to reveal two of the inner fluid conduit openings <NUM>,<NUM>. Actuator force applied to the control element <NUM> will move the control plate <NUM> to provide valve function as further explained below. A leak test groove <NUM> may be provided in the face of the valve body <NUM> to assist testing integrity of the seal <NUM> between the valve body <NUM> and the valve housing <NUM> which includes the diaphragm <NUM>.

Instead of a single circular orifice, applicant has devised a plurality of non-circular orifice ridge <NUM>, <NUM>, <NUM>, <NUM> structures (in this particular example a total of four) separating a plurality of inner fluid conduit openings <NUM>, <NUM>, <NUM>, <NUM> from a common outer cavity <NUM> of the valve chamber <NUM>. Each of the plurality of orifice ridges <NUM>, <NUM>, <NUM>, <NUM> may be formed as a closed non-circular circuit comprising a plurality of interconnected segments surrounding a corresponding inner fluid conduit opening <NUM>,<NUM>,<NUM>,<NUM>. For example, each non-circular circuit may include at least one curved segment and at least one straight segment. According to certain aspects, the plurality of interconnected segments may include at least one segment that curves away from the fluid conduit opening. According to other aspects, the plurality of interconnected segments may include at least one segment that curves toward the fluid conduit opening. The exemplary orifice ridge shapes may be considered to be like a plurality of adjacent circular sectors each with added smooth curves at the ends of the corresponding radius lines. According to some embodiments, the orifice ridge may include at least one curved segment that curves away from the fluid conduit opening that is adjacent to at least one straight or linear segment. According to other embodiments, the orifice ridge may include at least one curved segment that curves toward the fluid conduit opening that is adjacent to at least one straight or linear segment. The first inner fluid conduit opening <NUM> provides fluid communication with the first fluid conduit <NUM>. The second inner fluid conduit opening <NUM> also provides fluid communication with the first fluid conduit <NUM>. The third inner fluid conduit opening <NUM> provides fluid communication with the second fluid conduit <NUM>. The fourth inner fluid conduit opening <NUM> also provides fluid communication with the second fluid conduit <NUM>. The four inner fluid conduit openings <NUM>, <NUM>, <NUM>, <NUM> are thus all in parallel fluid communication with the flow collection region <NUM>. An outer fluid conduit opening <NUM> may provide fluid communication between the outer cavity <NUM> and the third fluid conduit <NUM>. The outer fluid conduit opening <NUM> may be disposed external to each of the plurality of orifice ridges <NUM>, <NUM>, <NUM>, <NUM>. The parts comprising said valve may be constructed from materials chosen for desired chemical inertness relative to the fluids to be handled and may include, for example, stainless steels, Monel® metals, titanium alloys, Hastelloy® nickel alloys, Elgiloy® cobalt alloy, copper alloys, aluminum alloys, or polymers such as Teflon®, Kel-F®, Vespel®, Kynar®, and combinations of metals and polymers either separate or together. For example, a type <NUM> stainless steel valve body <NUM> may be used with a Hastelloy® nickel alloy control plate <NUM>.

The potential flow restricting effects of the outer fluid conduit opening <NUM> may be lessened by enlarging the opening relative to the cross-sectional area of the corresponding fluid conduit <NUM>. Exemplary beneficial opening modifications may comprise an arcuate slot as illustrated, or a blended construction of other shaping such as flaring and beveling. The upper topmost portion of the plurality of orifice ridges <NUM>, <NUM>, <NUM>, <NUM> may be made very flat, planar and smooth by lapping, or similar manufacturing process, and those coplanar surfaces are herein referred to as contact tracks <NUM>, <NUM>, <NUM>, <NUM> of the plurality orifice ridges <NUM>, <NUM>, <NUM>, <NUM>. A control plate <NUM> having suitable likewise substantially planar control surface <NUM> of sufficient extent (typically a diameter) may rest against (make contact with) the entire plurality of contact tracks <NUM>, <NUM>, <NUM>, <NUM> to effectively close off all flow through the valve body <NUM>. The valve effective opening area, which is computed as an area defined by the periphery length of the plurality of orifice ridges <NUM>, <NUM>, <NUM>, <NUM> in fluid communication with the flow collection region <NUM> multiplied by any control gap between the planar control surface <NUM> and the contact tracks <NUM>, <NUM>, <NUM>, <NUM>, may be advantageously enlarged by the disclosed design. The length of the plurality of non-circular orifice ridge <NUM>, <NUM>, <NUM>, <NUM> peripheries may be made substantially greater than the circumference of a simple circular orifice occupying the same space.

Another exemplary valve design is illustrated in <FIG>, <FIG>, <FIG> comprises a valve body <NUM>, a first fluid conduit <NUM> (typically an inlet), a second fluid conduit <NUM> (typically an outlet), both of which conduits communicate fluid to a valve chamber <NUM>, a valve housing <NUM> which includes a valve chamber sealing diaphragm <NUM>, and a control element <NUM> moveable by deflection of the valve chamber sealing diaphragm <NUM>. A shank <NUM> may project from the sealing diaphragm <NUM> into the valve chamber <NUM> approximately centered on the axis of the control element <NUM>. A control plate <NUM> with a central thru-hole having a recessed opening <NUM> may be affixed to the shank <NUM> by deforming the end of the shank <NUM> within the recessed opening <NUM>. Actuator force applied to the control element <NUM> will move the control plate <NUM> to provide valve function as further explained below. The valve housing <NUM> and valve body <NUM> may be removably joined as a leak-free assembly by deforming a metallic gasket <NUM>.

A first orifice ridge <NUM> may be formed as a closed circuit comprising a plurality of interconnected segments surrounding an inner fluid conduit opening <NUM> and separating an inner valve cavity <NUM> from a first outer valve cavity <NUM> within the valve chamber <NUM>. According to certain aspects, each of the segments forming the closed circuit may be curved, and according to further aspects, the segments may form a closed circuit that is circular in shape. A first outer fluid conduit opening <NUM> may connect the first outer valve cavity <NUM> portion to the second fluid conduit <NUM>. The outer fluid conduit opening <NUM> may be disposed external to one or both of the first orifice ridge <NUM> and the second orifice ridge <NUM>. As discussed above, the valve design may further include a second orifice ridge <NUM> that is completely surrounded by the first orifice ridge <NUM>. The second orifice ridge 821may be formed as a closed circuit comprising a plurality of curved segments separating the inner valve cavity <NUM> from a second outer valve cavity <NUM> portion. As will be appreciated, either of the first or second orifice ridges <NUM> and <NUM> may be non-circular in shape. For example, either of the first or second orifice ridges <NUM> and <NUM> may be a kidney or petal or other shape that includes at least one segment that either curves away from or toward the fluid conduit opening, including the orifice ridge shape included in reference to <FIG>. A second outer fluid conduit opening <NUM> connected to the second fluid conduit <NUM> may be located within the second outer valve cavity <NUM> portion completely surrounded by the second orifice ridge <NUM>. The parts comprising said valve may be constructed from materials chosen for desired chemical inertness relative to the fluids to be handled and may include, for example, stainless steels, Monel® metals, titanium alloys, Hastelloy® nickel alloys, Elgiloy® cobalt alloy, copper alloys, aluminum alloys, or polymers such as Teflon®, Kel-F®, Vespel®, Kynar®, and combinations of metals and polymers either separate or together. For example, a type <NUM> stainless steel valve body <NUM> may be used with a Hastelloy® nickel alloy control plate <NUM>.

The potential flow restricting effects of the first outer fluid conduit opening <NUM>, and the inner fluid conduit opening <NUM>, may be lessened by enlarging the openings relative to the cross-sectional area of the corresponding fluid conduits <NUM>, <NUM>. Exemplary beneficial opening modifications may comprise arcuate slots as illustrated, or a blended construction of other shaping such as flaring and beveling. The upper topmost portion of the first and second orifice ridges <NUM>, <NUM> may be made very flat, planar and smooth by lapping, or similar manufacturing process, and those coplanar surfaces are herein referred to as contact tracks <NUM>, <NUM> of the first and second orifice ridges <NUM>, <NUM>. A control plate <NUM> having suitable likewise substantially planar control surface <NUM> of sufficient extent (typically a diameter) may rest against (make contact with) the entirety of both contact tracks <NUM>, <NUM> to effectively close off all flow through the valve body <NUM>. The valve effective opening area in fluid communication with the first fluid conduit <NUM> may be appreciated to be the sum of the lengths of the two contact tracks <NUM>, <NUM> multiplied by any control gap between the planar control surface <NUM> and the contact tracks <NUM>, <NUM>. Thus, this effective opening area is almost twice the area available from a similarly sized simple single circular orifice design as may be appreciated by consideration of the illustrated orifice ridges <NUM>, <NUM>.

As previously noted with respect to <FIG>, <FIG>, and <FIG>, the various exemplary valve designs that include multiple orifice ridge structures may be used to provide high conductance, but they may also be used in flow splitting applications. Such an exemplary flow splitting valve design is illustrated in <FIG>, <FIG>, <FIG> comprises a valve body <NUM>, a first fluid conduit <NUM> (typically an outlet), a second fluid conduit <NUM> (typically an inlet), and a third fluid conduit <NUM> (typically an outlet), each of which communicate fluid to a valve chamber <NUM>, a valve housing <NUM> which includes a valve chamber sealing diaphragm <NUM>, and a control element <NUM> moveable by deflection of the valve chamber sealing diaphragm <NUM>. A shank <NUM> may project from the sealing diaphragm <NUM> into the valve chamber <NUM> approximately centered on the axis of the control element <NUM>. A control plate <NUM> with a central thru-hole having a recessed opening <NUM> may be affixed to the shank <NUM> by deforming the end of the shank <NUM> within the recessed opening <NUM>. Actuator force applied to the control element <NUM> will move the control plate <NUM> to provide valve function as further explained below. A leak test groove <NUM> may be provided in the face of the valve body <NUM> to assist testing integrity of the seal <NUM> between the valve body <NUM> and the valve housing <NUM> which includes the diaphragm <NUM>.

In a manner similar to that described with respect to <FIG>, <FIG>, and <FIG>, the valve body <NUM> includes a first non-circular orifice ridge <NUM> structure separating a first inner cavity <NUM> from an outer cavity <NUM> of the valve chamber <NUM>. The first orifice ridge <NUM> may be formed as a closed non-circular circuit comprising a plurality of interconnected segments surrounding a first inner fluid conduit opening <NUM> in a path of changing curvature. Similar to the non-circular shapes discussed above, the plurality of interconnected segments may include at least one segment that curves away from the fluid conduit opening. The exemplary first orifice ridge <NUM> shape is again considered to be like a kidney shape, as explained above, in so far as said shape includes three segments that curve toward the fluid conduit opening and one segment that curves away from the fluid conduit opening. In this exemplary valve design, the first kidney-like orifice ridge <NUM> structure at least partially surrounds a second similar and smaller kidney-like second orifice ridge <NUM> structure. This configuration allows a second inner cavity <NUM> to be separated from the outer cavity <NUM>. Designers will appreciate any closed circuit shape may be implemented for the partially surrounded smaller second orifice ridge <NUM>. The illustrated kidney-like example comprises a plurality of interconnected segments surrounding a second inner fluid conduit opening <NUM>, where at least one segment is curved away from the second inner fluid conduit opening <NUM>. The valve body <NUM> with the orifice ridges <NUM>, <NUM> can be made by typical manufacturing processes such as milling, or casting, or injection molding, or recently developed additive manufacturing processes such as laser sintering (3D printing), for example. The valve body regions contacted by the controlled fluid may be subjected to additional processes, such as polishing and passivation, as is known in the art of high-purity fluid delivery.

The upper topmost portion of the first and second orifice ridges <NUM>, <NUM> may be made very flat, planar and smooth by lapping, or similar manufacturing process, and those coplanar surfaces are herein referred to as contact tracks <NUM>, <NUM> of the first and second orifice ridges <NUM>, <NUM>. A control plate <NUM> having suitable likewise substantially planar control surface <NUM> of sufficient extent (typically a diameter) may rest against (make contact with) the entirety of both contact tracks <NUM>, <NUM> to effectively close off all flow through the valve body <NUM>.

The first inner fluid conduit opening <NUM> provides fluid communication between the first inner cavity <NUM> and the first fluid conduit <NUM>. The second inner fluid conduit opening <NUM> may provide fluid communication between the second inner cavity <NUM> and the third fluid conduit <NUM>, which in this design is distinct from the first fluid conduit <NUM>. An outer fluid conduit opening <NUM> may provide fluid communication between the outer cavity <NUM> and the second fluid conduit <NUM>. The outer fluid conduit opening <NUM> is disposed external to each of the orifice ridges <NUM> and <NUM>. The parts comprising said valve may be constructed from materials chosen for desired chemical inertness relative to the fluids to be handled and may include, for example, stainless steels, Monel® metals, titanium alloys, Hastelloy® nickel alloys, Elgiloy® cobalt alloy, copper alloys, aluminum alloys, or polymers such as Teflon®, Kel-F®, Vespel®, Kynar®, and combinations of metals and polymers either separate or together. For example, a type <NUM> stainless steel valve body <NUM> may be used with a Hastelloy® nickel alloy control plate <NUM>.

In the exemplary valve design illustrated in <FIG>, <FIG>, <FIG>, an amount of fluid received at the outer fluid conduit opening <NUM> from the second fluid conduit <NUM> can be controllably split between the first inner fluid conduit opening <NUM> and second inner fluid conduit opening <NUM>, with the split ratio being determined based upon the ratio of the periphery length of orifice ridge <NUM> relative to the sum of the periphery length of orifice ridge <NUM> and the periphery length of orifice ridge <NUM>. For example, if the ratio of the periphery length of orifice ridge <NUM> relative to the sum of the periphery length of orifice ridge <NUM> and <NUM> were <NUM>, then second inner fluid conduit opening <NUM> would receive <NUM>% of the fluid received at outer fluid conduit opening <NUM>. Provided that the planar control surface <NUM> of the control plate <NUM> is maintained in a parallel position relative to both contact tracks <NUM>, <NUM> of the first and second orifice ridges <NUM>, <NUM>, the ratio of fluid provided to the first inner fluid opening <NUM> and the second inner fluid opening <NUM> will remain constant (up to where the area of the first and/or second inner fluid conduit openings <NUM>, <NUM> are limiting). To ensure that the ratio of fluid is determined by the ratio of the periphery length of the orifice ridges, potential flow restricting effects of the fluid conduit openings <NUM>, <NUM>, <NUM> may be lessened by enlarging the openings relative to the cross-sectional area of the corresponding fluid conduits <NUM>, <NUM>, and <NUM>. Exemplary beneficial opening modifications may comprise an arcuate slot as illustrated in the inner fluid conduit openings <NUM>, <NUM> or a blended construction of other shaping such as flaring and beveling as illustrated at the outer fluid conduit opening <NUM>.

Designers of fluid delivery apparatuses intended for proportional or modulating control of fluid flow (for example, mass flow controllers in semiconductor capital equipment) may appreciate the desirability of using a valve with maximum conductance appropriately matched to the intended apparatus maximum flow. A valve with insufficient conductance of course cannot provide the intended apparatus maximum flow, but a valve with excessive maximum conductance will force the apparatus to operate the valve only at the lowest settings and thus make control of the system potentially more difficult. Combinations of the several orifice ridge shapes described in this disclosure give the designer means to tailor the valve maximum conductance to match any particular application while staying within a chosen valve body size.

Claim 1:
A valve comprising:
a valve body (<NUM>; <NUM>; <NUM>; <NUM>) having a first fluid conduit opening (<NUM>; <NUM>; <NUM>; <NUM>);
an orifice ridge (<NUM>; <NUM>; <NUM>; <NUM>) disposed within the valve body (<NUM>; <NUM>; <NUM>; <NUM>) and a control plate (<NUM>; <NUM>; <NUM>; <NUM>) having a substantially planar control surface (<NUM>; <NUM>; <NUM>; <NUM>), the control surface configured to be positioned above the orifice ridge (<NUM>; <NUM>; <NUM>; <NUM>), wherein the valve body (<NUM>; <NUM>; <NUM>; <NUM>) includes a second fluid conduit opening, wherein the second fluid conduit opening is disposed external to the orifice ridge (<NUM>; <NUM>; <NUM>; <NUM>), characterised in that the orifice ridge (<NUM>; <NUM>; <NUM>; <NUM>) has a kidney shape having four interconnected segments that form a non-circular closed circuit surrounding the first fluid conduit opening (<NUM>; <NUM>; <NUM>; <NUM>), the four interconnected segments including three segments (A; B; C) that curve toward the first fluid conduit opening (<NUM>; <NUM>; <NUM>; <NUM>) in plan view and one segment (D) that curves away in plan view from the first fluid conduit opening (<NUM>; <NUM>; <NUM>; <NUM>).