Patent Publication Number: US-2003226605-A1

Title: Multi-port pinch valve and methods of manufacture thereof

Description:
CROSS REFERENCE TO RELATED APPLICATIONS  
     [0001] This application claims priority from U.S. Provisional Patent Application Serial No. 60/387,758, filed Jun. 11, 2002. 
    
    
     
       BACKGROUND OF THE INVENTION  
       [0002] 1. Field of the Invention  
       [0003] The present invention relates generally to pinch valve assemblies used in connection with conduit systems for transporting fluids in a conduit system and, in particular, to multi-port pinch valve assemblies for use in such systems and methods of manufacturing these valves.  
       [0004] 2. Description of Related Art  
       [0005] In order to move material, such as liquid, to specified or desirable locations, many industries use piping and diverter assemblies in order to safely transport materials. In many situations, such as mixing, diverting flow, unloading trailers and/or other bypass applications, it is desirable to use a one valve assembly with a single inlet port and two outlet ports. Such an assembly would be used in place of two separate valves with a “Y” piping connection between them. A “Y” pipe connection requires many different portions bolted together. In addition, valve assemblies are required that have any number of inlet and outlet ports, dependent upon the configuration and movement of material that is desired.  
       [0006] With respect to a three-ported valve, using a single valve assembly typically reduces installation labor costs and actuator costs, as a single actuator may be used to operate both outlet ports of a valve. While one port is typically closing, the other port is typically opening. However, the disadvantage of such a configuration is that the operating mechanism is somewhat complex. In addition, such a configuration decreases one&#39;s ability to independently control flow through the two outlet ports. Such three-port pinch valve assemblies are well known in the art.  
       [0007] In some applications, it is imperative to keep the “pockets” of residual material in the closed port section to a minimum. Using a diverter valve leads to smaller pockets than using two separate valves with a “Y” connection. For example, diverter valves are used extensively in food applications. Since larger pockets can accumulate a great volume of food, such as sugar or flour, such accumulation of food products makes them susceptible to decay. process material through the second section bore; and (d) withdrawing the flowing medium from the gap to retract the inner wall portion and thereby increase flow of the process material through the second section bore.  
       [0008] The present invention, both as to its construction and its method of operation, together with the additional objects and advantages thereof, will best be understood from the following description of exemplary embodiments when read in connection with the accompanying drawings. 
     
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
     [0009]FIG. 1 is a side sectional and schematic view of a multi-port pinch valve according to the present invention;  
     [0010]FIG. 2 is a perspective view of the multi-port pinch valve of FIG. 1;  
     [0011]FIGS. 3 a - 3   d  are side sectional and perspective views of a multi-port pinch valve in operation according to the present invention;  
     [0012]FIG. 4 is a side sectional view of an inner sleeve for a multi-port pinch valve in a first step of manufacture according to the present invention; and  
     [0013]FIG. 5 is a front view of the inner sleeve of FIG. 4. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
     [0014] The present invention is directed to a multi-port pinch valve  10 , which is illustrated in various stages of assembly and in operation in FIGS.  1 - 5 . As seen in FIG. 1, the multi-port pinch valve  10  includes at least one primary conduit section  12 , which is defined by a primary conduit section wall  14 , which further defines a bore. This primary conduit section  12  or bore contains material (not shown) that is transferred through the primary conduit section  12  for further movement in a conduit system (not shown). The multi-port pinch valve  10  also includes a plurality of branch conduit sections  16 . These branch conduit sections  16  are in fluid communication with the primary conduit section  12 , and as with the primary conduit section  12 , the branch conduit sections  16  contain material transferred therethrough.  
     [0015] Each of the branch conduit sections  16  are defined by a respective branch conduit section wall  18 . Further, the branch conduit section wall  18  has an outer sleeve portion  20 , a flexible inner sleeve portion  22  and a gap  24 . The gap  24  extends longitudinally along and at least hemi-cylindrically around at least a portion of the branch conduit section wall  18 . Further, the gap  24  is positioned between the outer sleeve portion  20  and the inner sleeve portion  22 .  
     [0016] In order to effect operation of the multi-port pinch valve, at least one injection mechanism  26  is in communication with the gap  24 . The injection mechanism  26  injects a flowing medium, such as gas or fluid, into the gap  24 . This causes the flexible inner sleeve portion  22  to expand and flex into a branch conduit section inner area  28  or bore. In this manner, the expansion of the inner sleeve portion  22  into the branch conduit section inner area  28  restricts the flow of material through the branch conduit section  16  and allows for the appropriate control of material flow. In addition, and in order to allow appropriate flexibility in operation, the outer sleeve portion  20  is substantially rigid, while the inner sleeve portion  22  is substantially dynamic.  
     [0017] In order to provide rigidity to the outer sleeve portion  20 , the outer sleeve portion  20  may include a reinforcement layer  30 . In one preferred and non-limiting embodiment, the reinforcement layer  30  is at least one wire member  32  that extends at least partially around and is in operative communication with (i.e., it is embedded within or wrapped around the outside of) the outer sleeve portion  20 . This wire member  32  imparts the required rigidity to the outer sleeve portion  20 . It is also envisioned that the reinforcement layer  30  can be constructed of fabric, mesh and/or any other appropriate material having the required rigidity characteristics. In addition, the wire member  32  can be integral with and extend within the outer sleeve portion  20 . In creating such a structure, the wire member  32  is formed and bonded with the outer sleeve portion  20 .  
     [0018] In order to be flexible and dynamic, the inner sleeve portion  22  should be constructed from a material having the appropriate flexibility and elastomeric properties. For example, the inner sleeve portion  22  can be constructed from an elastomer, rubber, a polymer, or any other flexible material with memory characteristics and of ______ durameter. However, the material of construction of the inner sleeve portion  22  must be able to flex into the branch conduit section inner area  28  when the injection mechanism  26  injects material into the gap  24 , and when this material is removed from the gap  24 , the inner sleeve portion  22  must return to its original position. The constant flexing of the inner sleeve portion  22  may cause damage to the structure of the inner sleeve portion  22  after repeated use. Therefore, the inner sleeve portion  22  may also include the reinforcement layer  30  in order to provide structural support to the inner sleeve portion  22 . However, this reinforcement layer  30  must still allow for the appropriate flexing of the inner sleeve portion  22 . In one preferred and non-limiting embodiment, the reinforcement layer  30 , for use in connection with the inner sleeve portion  22 , is a fabric member that extends at least partially around and is in operative communication with inner sleeve portion  22 .  
     [0019] In one preferred and non-limiting embodiment, the injection mechanism  26  includes an injection device  34  that is in communication with a fitting  36 , which is connected to an outer surface  38  of a branch conduit section  16 . The fitting  36  is in communication with an injection passageway  40 , which is, in turn, in communication with the gap  24 . In operation, the injection device forces a gas or fluid through the fitting  36 , further through the injection passageway  40  and into the gap  24 . Accordingly, the gap  24  will expand and flex the inner sleeve portion  22  into the branch conduit section inner area  28 , thereby restricting flow through this branch conduit section  16 . While the injection mechanism  26  (or injection device  34 ) typically injects gas, such as air, any suitable fluid such as water or the like may be utilized. In a preferred embodiment, the injection mechanism  26  injects air into the gap  24 .  
     [0020] In another preferred embodiment, rather than being manually controlled, the multi-port pinch valve  10  includes a control mechanism  42  in communication with the injector mechanism  26 . The control mechanism  42  controls the injection of the gas or liquid into the gap  24 . This control mechanism  42  can be in the form of a personal computer, a printed circuit board, a central processing unit, a processing device, a controller, etc. Further, the control mechanism  42  allows an operator to proportionally control the injection of material into the gap  24  of one or more of the branch conduit sections  16 .  
     [0021] It is also envisioned that each of the plurality of branch conduit sections  16  has a respective injection mechanism  26  in communication with a respective gap  24 . In this embodiment, each injection mechanism  26  is in communication with and controlled by the control mechanism  42 , which controls the injection of gas or fluid into each respective gap  24 . Again, this can be used for proportional control of each respective branch conduit section  16 . For example, an inner sleeve portion  22  of one branch conduit section  16  can be “throttled back,” while another inner sleeve portion  22  of a branch conduit section  16  can be further expanded into the branch conduit section inner area  28 . In addition, in order to permit the air or liquid in the gap  24  to be removed from the gap  24 , the injection mechanism  26  may also include a relief device  44 . This relief device  44  would permit the gas or fluid to be relieved from the gap  24  and either discarded or diverted for further reuse.  
     [0022] In another embodiment, the multi-port pinch valve  10  may include or be formed with one or more connection mechanisms  46  positioned on ends of the branch conduit section  16  and/or the primary conduit section  12 . These connection mechanisms  46  would allow the multi-port pinch valve  10  to be connected to other fittings on and throughout the piping or conduit system in a manufacturing facility. In a preferred embodiment, the connection mechanism  46  is a flange  48  positioned on an end of each of the branch conduit sections  16  and the primary conduit section  12 . Further, these flanges  48  include bolt holes  50  for securely attaching the multi-port pinch valve  10  to another flange in the conduit system. However, it is envisioned that any suitable connection mechanism  46  can be used, such as a cuff, a clamp, etc.  
     [0023] When using air as the medium for injection by the injection mechanism  26  into the gap  24 , an operating air pressure of approximately 30 psi more than the internal line pressure may be required. This would enable the multi-port pinch valve  10  to fully close each branch conduit section  16 . Therefore, it is appropriate to use the above-discussed reinforcement layer  30  to suitably reinforce and contain this operating air pressure.  
     [0024]FIGS. 3 a - 3   d  illustrate the multi-port pinch valve  10  in operation. Due to the hemi-cylindrical shape of the gaps  24 , the outer halves of the inner sleeve portions  22  are capable of being flexed toward the branch conduit section inner area  28  and brought into contact with a branch conduit section opposite wall  52 . When such contact occurs, material flow through the “closed” branch conduit section  16  is prevented. See FIG. 3 d . The inner sleeve portion  22  is closed from one side, by bulging inward from the full round position. Only about 180 degrees of the circumference bulges inward, due to the positioning of the gap  24 . The remaining 180 degrees is fixed to the branch conduit section opposite wall  52 . When the branch conduit section  16  in operation is almost fully closed, the opening for the process material or fluid to pass through is about 180 degrees and “C” shaped. In a preferred embodiment, all branch conduit sections  16  operate in this manner.  
     [0025] The present invention is also directed to a method of manufacturing the multi-port pinch valve  10 . As seen in FIGS. 4 and 5, a first layer of material is wrapped around a rigid mandrel or form (not shown), thereby creating the inner sleeve portion  22  having a first wall layer defining a primary conduit section  12  and a plurality of branch conduit sections  16 . In a preferred embodiment, the form is manufactured from steel or other rigid material, and the first layer of material is a fabric-reinforced elastomer. It is necessary that this inner sleeve portion  22  be capable of flexing. Next, a second layer of material is placed or plied over the first layer of material, thereby creating the outer sleeve portion  20  comprising a second wall layer. The gap  24  is formed between at least a portion of the inner sleeve portion  22  and the outer sleeve portion  20  in one or more of the branch conduit sections  16 . Finally, the first and second layers of material are cured.  
     [0026] In order to create the gap  24 , a release agent (of a type known to those skilled in the art) may be applied to the desired portion of the inner sleeve portion  22  or first layer of prior to applying the second layer of material. This release agent is used to prevent adhesion between the first and second layers of material during the curing process. When using a rubber material as the primary compound in the inner sleeve portion  22  and the outer sleeve portion  20 , the curing process is referred to as a vulcanization process. After vulcanization or curing, and due to the application of the release agent, the gaps  24  or slits are created in the areas where the release agent was used in the branch conduit sections  16 . When using the reinforcement layer, such as the wire member  32  or other rigid material, this reinforcement layer  30  is wrapped around the inner sleeve portion  22  or first layer of material prior to application of the second layer of material or outer sleeve portion  20 . Thus, after vulcanization or curing, the outer sleeve portion  20  and the wire member  32  form a substantially rigid area. Since the wire member  32  is not formed with the inner sleeve portion  22 , the inner sleeve portion  22  remains dynamic and flexible.  
     [0027] In one preferred and non-limiting method of manufacture, after the inner sleeve portion  22 , wire member  32  and outer sleeve portion  20  are positioned on the mandrel, the entire multi-port pinch valve  10  is wrapped tightly with an outer pressure material prior to curing. This outer pressure material can be, for example, nylon tape. The purpose of this wrapping is to provide pressure on all layers of material during the vulcanization process. Next, the multi-port pinch valve  10  is placed into a steam pressure vessel and vulcanized into a single solid mass. After vulcanization, which typically requires several hours, the entire multi-port pinch valve  10  is removed from the pressure vessel and allowed to cool. However, it is noted that any manufacturing method for attaining the above-described multi-port pinch valve  10  and its various components is envisioned. Other methods, such as a steel mold, can be used to apply pressure to the multi-port pinch valve  10 . Further, as opposed to using the release agent in creating the gap  24 , a thin sheet of material, such as Teflon®, may be inserted, which would not bond to the other portions.  
     [0028] While the present invention has described a multi-port pinch valve  10  illustrated with two branch conduit sections  16 , any number of branch conduit sections  16  and/or primary conduit sections  12  are envisioned. Any number of flow patterns and material transfer operations can be achieved by using the multi-port pinch valve  10 . For example, the branch conduit section  16  and primary conduit section  12  can be switched between being inlets and outlets, with respect to the material flow through the branch conduit section  16  and the primary conduit section  12 . For example, such an arrangement could be used in connection with a mixing application with different types of temperatures and material or fluid flowing through individual inlet portions, mixed and flowing through a common or outlet portion. Still further, some branch conduit sections  16  may not require control and may not use or be formed with an outer sleeve portion  20  and a flexible inner sleeve portion  22 .  
     [0029] It is also envisioned that any one of the branch conduit sections  16  with a primary conduit section  12  can be constructed with varying bore configurations, for example, a cone sleeve. In this manner, the multi-port pinch valve  10  can be configured having legs of unequal size and with several different bore configurations. For example, one branch conduit section  16  could have a four-inch full-ported bore, and the other branch conduit section  16  could have a two-inch cone-shaped bore. This configuration may be especially useful in the mixing application discussed above.  
     [0030] Overall, the multi-port pinch valve  10  is simple in its construction and easy in its operation. There are no complex mechanical parts, and the branch conduit sections  16  may be operated independently of each other by controlling the amount of operating air pressure applied by the injection mechanism  26 , as controlled by the control mechanism  42 . Therefore, each branch conduit section  16  may be fully opened, fully closed, or partially closed, independently of the others.  
     [0031] This invention has been described with reference to the preferred embodiments. Obvious modifications and alterations will occur to others upon reading and understanding the preceding detailed description. It is intended that the invention be construed as including all such modifications and alterations.