Patent Publication Number: US-7712486-B2

Title: Modular surface mount manifold

Description:
RELATED APPLICATIONS 
   The present application is a continuation of pending U.S. Ser. No. 11/685,486 filed on Mar. 13, 2007, for MODULAR SURFACE MOUNT MANIFOLD, which application is pending issue, which is a continuation of U.S. Ser. No. 11/194,409 filed on Aug. 1, 2005, for MODULAR SURFACE MOUNT MANIFOLD, now U.S. Pat. No. 7,195,037, which is a continuation of U.S. Ser. No. 10/605,268 filed on Sep. 18, 2003, for MODULAR SURFACE MOUNT MANIFOLD, now U.S. Pat. No. 6,938,644, which is a divisional application of U.S. Ser. No. 09/719,727 filed on Jun. 7, 2001, for MODULAR SURFACE MOUNT MANIFOLD, now U.S. Pat. No. 6,644,353, itself a national phase entry under 35 U.S.C. §371 and claims priority to International Application No. PCT/US99/04972, with an International Filing Date of Mar. 5, 1999, for MODULAR SURFACE MOUNT MANIFOLD which claims the benefit of U.S. Provisional Application Ser. No. 60/076,871, filed Mar. 5, 1998, for MODULAR SURFACE MOUNT MANIFOLD which are all fully incorporated by reference herein. 

   FIELD OF THE INVENTION 
   The invention relates in general to manifolds for fluid systems, and more particularly, the invention relates to a modular gas distribution system for use in high purity fluid systems and corrosive fluid systems such as the clean room environment used to manufacture semiconductor wafers. 
   BACKGROUND OF THE INVENTION 
   This application claims the benefit of U.S. provisional application No. 60/076,871 filed on Mar. 5, 1998. 
   To manufacture semiconductors, the industry uses various high purity gases. These gases are controlled by systems made up of high purity valves, regulators, pressure transducers, mass flow controllers and other components connected together by welding and high purity metal seal fittings. These connections are undesirable in many applications because they add additional time and cost for welding operations, unnecessary space between components and make it difficult to replace a component located between other components. Further, these systems are typically custom designed and manufactured which make the manufacturing costs and procurement of replacement parts quite expensive. 
   New modular manifold systems have been recently introduced into the industry in order to overcome these problems. Typical components of these systems such as valves, pressure regulators and other typical fluid components have been reconfigured so that their inlet and outlet ports and attachment mechanisms are compatible with surface mount manifolds. These manifolds are typically comprised of modular blocks which are machined of high purity metal and have machined internal flow passageways. These prior art modular systems typically utilize a metallic seal between the component and a modular block face to ensure near leak-free seal integrity. One objective of such systems is to use surface mount standard configurations based upon industry standards to permit interchangeability of surface mount components. 
   One disadvantage to these type of prior art modular systems is that the entire modular block is made of high purity metal. Thus money and natural resources are inefficiently utilized. Further, these block components also have higher manufacturing costs due to the complexity of machining multiple passageways of a single block as well as a higher risk of expensive scrap being formed due to the manufacturing complexity. Further, the mating blocks require the use of mating seals therebetween, which require additional manufacturing time, and further require proper installation and makeup torque of the fastener members in order to ensure a leak-tight seal. 
   SUMMARY OF THE INVENTION 
   Thus it is desired that a modular manifold design be provided which eliminates the seals between modular mating blocks, dramatically reduces the amount of expensive material utilized, and results in a simpler and cheaper system to manufacture while providing a reduced system footprint or envelope which meets or surpasses the performance, integrity and reliability of existing systems. 
   The invention provides in one aspect a bridge fitting for use in a fluid manifold system for being in fluid communication with two or more fluid components, such as valves, regulators, pressure transducers, mass flow controllers, and the like. The bridge fitting comprises a first elbow fitting connected to a second elbow fitting, with the connected elbow fittings having an internal fluid passageway therethrough. The internal passageway of the bridge fitting has an inlet end and an outlet end, with the inlet end in fluid communication with an outlet port of the first fluid component, and the outlet end of the bridge fitting in fluid communication with an inlet end of a second fluid component. 
   The invention provides in another aspect a bridge fitting for use in a fluid manifold system for being in fluid communication with three or more fluid components, wherein one or more of said fluid components has a single port. The bridge fitting comprises a first and second elbow fitting having a respective end connected to a tee fitting. The tee fitting is located between the elbow fittings, with each of the elbow fittings and the tee fittings having an internal fluid passageway in fluid communication with each other. The internal passageway of the fittings have an inlet end and a first and second outlet end, with the inlet end in fluid communication with an outlet port of the first fluid component, and the outlet ends of the fluid passageway being in fluid communication with an inlet end of a second and third fluid component, respectively. 
   The invention provides in yet another aspect a modular fluid manifold system for connecting with one or more surface mount type fluid components having an inlet port and an outlet port, the modular system comprising: one or more bridge fittings having an internal fluid passageway therethrough; the internal passageway of the bridge fitting having an inlet end for connecting to an outlet port of the first fluid component, and an outlet end for connecting to an inlet port of the second fluid component, whereby the internal fluid passageway of the bridge fitting is in fluid communication with the first and second fluid components when the system is assembled. 
   Finally, the invention provides a modular fluid manifold system for connecting with one or more fluid components comprising an inlet port and one or more outlet ports. The manifold system comprises one or more bridge fittings having an inlet end and an outlet end and an internal passageway joining said ends therethrough. The system further includes a locator plate having an upper surface for mounting the fluid components thereon and a plurality of holes aligned with the inlet and outlet ports of the fluid components. The locator plate has a lower surface for mounting the bridge fittings thereto. The inlet end of each of the bridge fittings are in fluid communication with an outlet port of a fluid component, and an outlet end of each of the bridge fittings are in fluid communication with an inlet port of another fluid component. 
   These and other features and advantages of the invention will become apparent in the detailed description and claims to follow, taken in conjunction with the accompanying figures. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention may take physical form in certain parts and arrangements of parts, a preferred embodiment of which will be described in detail in this specification and illustrated in the accompanying drawings which form a part hereof, and wherein: 
       FIG. 1  is a perspective view of the complete manifold assembly shown with representative components and seals incorporating features of the subject invention; 
       FIG. 2  is an exploded perspective of a manifold assembly and representative components and seals incorporating features of the subject invention as shown in  FIG. 1 ; 
       FIG. 3  is an exploded elevational view of a portion of the manifold of  FIG. 2 , showing one complete gas bridge located between two partially illustrated gas bridges and showing an optional representative seal; 
       FIG. 3   a  is a cross-sectional view of the assembled manifold portion of  FIG. 2 ; 
       FIG. 3   b  is a cross-sectional view of an alternative gas bridge incorporating a tee fitting and an additional tube section, in addition to the two elbows and the tube section shown in the complete gas bridge  8  illustrated in  FIGS. 3 and 3   a ; and 
       FIG. 4  is a perspective view of a alternative manifold system of the present invention which incorporates multiple flow paths extending in various directions. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   Referring now to the drawings wherein the drawings are for the purposes of illustrating the preferred embodiments of the invention only and not for purposes of limiting same, a unique manifold system is shown in the  FIGS. 1-4 . The inventions as shown and described in the Figures are useful, for example, as part of a high purity modular gas distribution system used in the manufacture of semiconductor devices or other fluid systems which must withstand corrosive fluids. The present invention is not limited to the use in high purity fluid systems, and may be useful in any application relating to fluid flow control. 
   Now referring to the drawings and more particularly  FIG. 1 , a modular fluid manifold system  10  is shown assembled together with fluid flow control components such as valves  12 , flow regulators  13 , filters  14  and the like. The fluid components may be utilized in conjunction with the invention, but are not part of the invention. The fluid components  12 - 14  are preferably surface mount type components, and each component has an inlet port  16  and may additionally comprise one or more outlet ports  18  as shown in  FIG. 3A , which allow fluid communication to the fluid component. A series of fasteners  22  of the fluid components pass through openings  24  in the base flanges  26  of the fluid components in order to secure the components to the modular manifold system  10 . 
   The modular manifold system  10  of the present invention may comprise one or more bridge fittings  50 , an optional locator plate  30 , an optional backing plate  40 , optional end fittings  45 , and optional sealing elements  60 . These elements are described in more detail, below. The bridge fittings  50 , as shown in  FIG. 3 , are in the form of two elbow fittings  52  which are shown joined by an optional tubular extension  54  connected to the respective ends of the elbow fittings  52  by conventional means such as by orbital welding. The elbow fittings  52  have an interior fluid passageway  56  having an inlet end  58  and an outlet end  62 , 64 , with the inlet end  58  having a 90 degree orientation with respect to the outlet end  62 , 64 . The optional tubular extension  54  has an internal fluid passageway which connects with the adjoining fluid passageway of the two adjacent elbow end fittings  52 , such that a U shaped fluid passageway is formed within the interior of the bridge fitting  50 , with the passageway having an inlet end  62  and an outlet end  64 . As shown in  FIG. 3A , the inlet end  62  of the bridge fitting  50  is in fluid communication with a respective outlet opening  18  of a fluid component  12 , and the outlet end  64  of the bridge fitting  50  is in fluid communication with the inlet of an adjacent fluid component  13 . Thus the bridge fitting  50 , acts as a “bridge” to transfer fluid between adjacent fluid components such as  12 , 13  without the need for metal to metal seals between adjacent bridge fittings  50 , which is typically required by the mating of adjacent prior art modular blocks. It is preferred that the bridge fitting  50  be comprised of stainless steel such as 316 or SCQ, or other material suitable for use in conjunction with semiconductor processing fluids. For typical industrial applications, any suitable material such as plastic or metal would work for the invention. 
   As shown in  FIG. 1 , the modular system  10  may also comprise end fittings  45 , which comprise an elbow fitting having a 90 degree internal passageway connected to a standard fitting  46 , such as a standard VCR-type fitting or other suitable fitting for connecting with a fluid line. The end fitting  45  may be utilized as an inlet fitting or an outlet fitting which mates with the fluid line (not shown). Thus, the outlet or inlet end of the elbow fitting is connected to the respective inlet or outlet end of a fluid component. It is preferred that the end fittings  45  be comprised of stainless steel, 316 stainless, SCQ stainless or other material suitable for use in conjunction with semiconductor processing fluids. For typical industrial applications, the end fittings  45  may be comprised of any suitable material such as plastic or metal. 
   The modular manifold system  10  of the present invention may further optionally comprise a backing plate  40 . The backing plate  40  may comprise a flat plate, but it preferably has an interior groove or channel  42  for receiving and securing a plurality of bridge fittings  50  and end fittings  45  therein. Each elbow fitting  52  of the bridge fitting  50  and the end fitting  45 , has an exterior shaped body of a precise dimension which mates with the shape of the groove or channel  42 . It is preferred but not required that the external shape of the elbow fitting  52  be rectangular or square. It is also preferred that the internal side walls  44  forming the channel  42  have a suitable dimension for closely receiving a square shaped body, or that two of the opposed side walls have an appropriate dimension for receiving a rectangular shaped body. The invention is not limited to the above mentioned shapes, as any complementary shaped channel with respect to the shaped body of the elbow fitting  52  would work for the invention. The backing plate  40  may be comprised of any suitable material such as metal, but it is preferably made of a low-cost lightweight material such as aluminum. 
   In one embodiment of the invention (not shown), the channel  42  is of a sufficient depth such that the bridge fittings  50  and the end fittings  45  can be completely received within the channel  42  such that a recess is formed (not shown) for receiving a seal  60  between the inlet  62  and outlet  64  of the bridge fittings and the opposed channel walls  44 . In order to assemble the system in this embodiment, the bridge fittings  50  are inserted within the channel  42  of the backing plate  40 , such that the bridge fittings  50  are spaced to have minimal clearance between adjoining bridge fittings  52 . Next, the inlet and outlet ports of the fluid components  12 - 14  are carefully aligned with the respective outlet and inlet ports of the pertinent bridge fittings. For example, an inlet end of a first bridge fitting  50  is aligned for fluid communication with an outlet of a first fluid component. Next, the outlet end of the first bridge fitting  50  is aligned with the inlet of a second fluid component which is adjacent to the first fluid component. After the inlet and outlet ports are carefully aligned, the fasteners  22  are inserted through holes  24  of the flanges  26  of the fluid components and into mating holes (not shown) of the backing plate  40 , such that the fluid components are secured to the backing plate  40 . 
   It is preferable that the manifold system  10  further comprise seals  60 , which are received between the mating inlet/outlet ports of the bridge fittings  50  and the fluid components. The seals  60  may be made of any suitable material such as elastomer, plastic, rubber or polymer material and preferably, a soft metal such as nickel. C seals may also be used, as well as composite seals to name additional examples. Other seal technologies which may used in conjunction with the invention will be readily apparent to those ordinarily skilled in the art. 
   In a second embodiment of the invention as illustrated in  FIGS. 2 ,  3  and  3 A, an optional locator plate  30  may be utilized with the invention. The locator plate  30  has a plurality of holes aligned to receive the ends  62 , 64  of the bridge fittings  50  therein. The ends of the bridge fittings  50  are preferably slightly shorter than the thickness of the locator plate  30  such that a recess is formed for receiving a seal  60  therein. The locator plate  30  additionally has holes  32  aligned for receiving fasteners  22  therein. Thus in order to assemble the system pursuant to the second embodiment of the invention, the bridge fittings are placed within the channel  42  of the backing plate  40 , and then the holes of the locator plate are aligned with the inlet and outlet end of the bridge fittings  50 . The locator plate is then lowered into position such that the ends of bridge fittings  50  are inserted through the aligned holes  34  of the locator plate  30 . Fasteners  36  are then inserted through aligned holes  38  of the backing plate for reception into aligned holes  39  of the locator plate  30 . Lastly, the fluid components  12 - 14  are then secured to the locator plate  30  using fasteners  22 . 
   An alternative embodiment of a bridge-tee fitting  70  is shown in  FIG. 3   b . This bridge fitting  70  may be used in conjunction with three adjacent fluid components, wherein the middle fluid component has only one inlet port, e.g., a pressure transducer. The bridge fitting  70  is comprised of two elbow fittings  52 , each having an internal fluid passageway in fluid communication with a tee fitting  72 . The tee fitting  72  has an inlet end  74 , and two outlet ends  76 ,  78 . Outlet end  76  of the tee fitting  70  is in fluid communication with the inlet of a single port fluid component such as a pressure transducer. The outlet end  78  of the tee fitting is in fluid communication with the outlet end  80  of the bridge fitting. Thus the bridge tee fitting  70  has an inlet end  82  and two outlet ends  76  and  80 , and may be used to “bridge” or transfer the flow between three adjacent fluid components, wherein the middle fluid component has only a single port. 
     FIG. 4  shows yet another embodiment of a locator plate  80  designed for use with fluid flowing in multiple flow paths A, B, C and D. In order to better illustrate the invention, the backside of the locator plate is shown with respect to the bridges  50  (i.e., the opposite of  FIG. 2 ). The arrangement of the bridges  50  within the holes  82  of the locator plate allow for the combination or mixing of fluids from one or more flow paths. Thus as shown in  FIG. 4 , four independent flow paths are shown (A, B, C and D) which are mixed together in desired proportions by fluid components (not shown) which result in the fluid outlet  86  of the system to be comprised of the fluids A, B, C and D mixed in a desired proportion. This is accomplished by using a fluid component such as a valve having a three port configuration (at locations  84 ) in order to allow for the mixture of the different fluids from separate flow paths. Note that the bridge fittings  50  are combined in a “pegboard” style arrangement in order to achieve the desired result as described above. Thus bridges  50  are used to interlink or join the separate flow paths in order to achieve the fluid mixing, without the need for any specially adapted components. This is a distinct advantage over prior art block type modular designs, as a special block having three ports would be needed. 
   In this embodiment of the invention, the locator plate  80  may be used to both as a support for the bridges  50  and as a “locator” without the need for a support plate. The bridge fittings  50  may further comprise a threaded end (not shown) which can be inserted into aligned threaded holes  82  of the locator plate  80 . The ends  62 , 64  of the bridge fittings  50  may also be press fit into the aligned holes  82  of the locator plate  80  or be attached by retainer clips (not shown) to the locator plate. Other attachment means may be readily apparent to those ordinarily skilled in the art. 
   In this embodiment of the invention, the ends  62 , 64  of the bridge fittings  50  may vary in height, with a height sufficient to allow multiple layers of bridge fittings (not shown). 
   This cross layer feature would be useful, for example, if it were desired to provide purge gas in Line A to the other gas lines B, C and D. In order to accomplish this, a modified bridge fitting  50  would be needed which would additionally comprise a tee fitting for mating with the bridge fitting of an upper layer. The tee fitting would be located between the elbow fittings as shown in  FIG. 3   b , and have an internal fluid passageway in communication with the internal fluid passageways of the elbow fittings. However, unlike  FIG. 3B , the opening of the tee fitting would be 180 degrees opposite of the openings of the elbow fittings in order to mate with the tee fitting of a bridge fitting located in another layer. Thus this embodiment of the invention would result in a fluid manifold system having multiple fluid flow paths, with said paths being capable of extending in multiple directions. Further, this embodiment allows for multiple or three dimensional layering of gas flow paths, wherein the fluid flow paths of one layer may be in fluid communication with the fluid flow path of another layer(s). 
   In summary, the invention provides a bridge fitting which may be used to form a gas or fluid flow path in conjunction with fluid components which are preferably surface mount components. These bridge fittings eliminate the need for mating seals needed between adjacent blocks of the prior art, and they are much simpler and cheaper to manufacture. Further, the invention provides for easy installation of multiple fluid flow paths and fluid components in multiple directions and layers. The invention also provides for the interchangeability of fluid components while allowing easy access to the components for ease of maintenance. 
   While the preferred embodiments of the invention has been illustrated and described, it should be understood that variations will become apparent to those skilled in the art. Accordingly, the invention is not limited to the specific embodiments illustrated and described herein, but rather the true scope and spirit of the invention are to be determined by reference to the appended claims.