Patent Publication Number: US-7717682-B2

Title: Double diaphragm pump and related methods

Description:
RELATED APPLICATION 
   This application claims priority to U.S. Provisional Application Ser. No. 60/699,262 titled DOUBLE DIAPHRAGM PUMP AND RELATED METHODS which was filed on Jul. 13, 2005 for Troy J. Orr. Ser. No. 60/699,262 is hereby incorporated by reference. 

   TECHNICAL FIELD 
   The present invention relates generally to the field of fluid transfer. More particularly, the present invention relates to transferring fluids which avoid or at least minimize the amount of impurities being introduced into the fluid. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Understanding that drawings depict only typical embodiments of the invention and are not therefore to be considered to be limiting of its scope, the invention will be described and explained with additional specificity and detail through the use of the accompanying drawings. The drawings are listed below. 
       FIG. 1  is a perspective view of the double diaphragm pump. 
       FIG. 2  is an exploded perspective view of the double diaphragm pump. 
       FIG. 3A  is a side view of the inner side of the left motive fluid plate with the interior shown in phantom. 
       FIG. 3B  a side view of process fluid body with the interior shown in phantom. 
       FIG. 3C  is a perspective view of the inner side of the right motive fluid plate with the interior shown in phantom. 
       FIG. 4A  is a side view of the left motive fluid plate which shows cutting lines  4 B- 4 B and  4 C- 4 C. 
       FIG. 4B  is a cross-sectional view of the double diaphragm pump taken along cutting line  4 B- 4 B in  FIG. 4A . 
       FIG. 4C  is a cross-sectional view of the double diaphragm pump taken along cutting line  4 C- 4 C in  FIG. 4A . 
       FIG. 4D  is a view of an end of the double diaphragm pump which shows cutting lines  4 E- 4 E,  4 F- 4 F, and  4 G- 4 G. 
       FIG. 4E  is a cross-sectional view of the double diaphragm pump taken along cutting line  4 E- 4 E in  FIG. 4D . 
       FIG. 4F  is a cross-sectional view of the double diaphragm pump taken along cutting line  4 F- 4 F in  FIG. 4D . 
       FIG. 4G  is a cross-sectional view of the double diaphragm pump taken along cutting line  4 G- 4 G in  FIG. 4D . 
       FIG. 5  is a schematic view of a double diaphragm pump as used in a method and system for transferring fluid. The system has a single pressure/vacuum valve. 
       FIG. 6  is a chart of the pressure over time of the motive fluid in the system depicted in  FIG. 5 . 
       FIG. 7  is a schematic view of a double diaphragm pump as used in a method and system for transferring fluid. The system has two pressure/vacuum valves. 
       FIG. 8  is a chart of the pressure over time of the motive fluid in the system depicted in  FIG. 7 . 
       FIG. 9A  is a diaphragm media before the regions have been formed. 
       FIG. 9B  is a diaphragm media after the regions have been formed. 
       FIG. 10A  is an exploded perspective view of a forming fixture used to form the regions in the diaphragm media. 
       FIG. 10B  is a cross-sectional view of a forming fixture after a diaphragm media has been loaded to be pre-stretched used to form the regions in the diaphragm media. 
       FIG. 10C  is a cross-sectional view of the forming fixture forming the regions in the diaphragm media. 
       FIG. 10D  is a cross-sectional view of the forming fixture after the regions in the diaphragm media have been formed. 
   

   INDEX OF ELEMENTS IDENTIFIED IN THE DRAWINGS 
   
     
       
         
             
           
             
                 
             
             
               Elements numbered in the drawings include: 
             
             
                 
             
           
          
             
                 
             
          
         
         
             
             
          
             
               100 
               double diaphragm pump 
             
             
               101i 
               first inlet valve chamber 
             
             
               101o 
               first outlet valve chamber 
             
             
               102i 
               second inlet valve chamber 
             
             
               102o 
               second outlet valve chamber 
             
             
               103l 
               left pump chamber or first pump chamber 
             
             
               103r 
               right pump chamber or second pump chamber 
             
             
               110 
               process fluid body 
             
             
               111i 
               first inlet valve seat 
             
             
               111o 
               first outlet valve seat 
             
             
               112i 
               second inlet valve seat 
             
             
               112o 
               second outlet valve seat 
             
             
               113l 
               left pump chamber cavity or first pump chamber cavity 
             
             
               113r 
               right pump chamber cavity or second pump chamber cavity 
             
             
               114l 
               surface of left pump chamber 113l 
             
             
               114r 
               surface of right pump chamber cavity 113r 
             
             
               115l 
               inclined region of left pump chamber 113l 
             
             
               115r 
               inclined region of right pump chamber cavity 113r 
             
             
               116l 
               rim of left pump chamber 113l 
             
             
               116r 
               rim of right pump chamber cavity 113r 
             
             
               117l 
               perimeter of left pump chamber cavity 113l 
             
             
               117r 
               perimeter of right pump chamber cavity 113r 
             
             
               118i 
               perimeter of first inlet valve seat 111i 
             
             
               118o 
               perimeter of first outlet valve seat 111o 
             
             
               119i 
               perimeter of second inlet valve seat 112i 
             
             
               119o 
               perimeter of second outlet valve seat 112o 
             
             
               121i 
               groove of first inlet valve seat 111i 
             
             
               121o 
               groove of first outlet valve seat 111o 
             
             
               122i 
               groove of second inlet valve seat 112i 
             
             
               122o 
               groove of second outlet valve seat 112o 
             
             
               130i 
               inlet line 
             
             
               130o 
               outlet line 
             
             
               131i 
               first inlet valve portal for fluid communication between inlet line 
             
             
                 
               130i and first inlet valve seat 111i 
             
             
               131o 
               first outlet valve portal for fluid communication between first 
             
             
                 
               outlet valve seat 111o and outlet line 130o 
             
             
               132i 
               second inlet valve portal for fluid communication between inlet 
             
             
                 
               line 130i and second inlet valve seat 112i 
             
             
               132o 
               second outlet valve portal for fluid communication between 
             
             
                 
               second outlet valve seat 112o and outlet line 130o 
             
             
               138i 
               inlet line extension 
             
             
               138o 
               outlet line extension 
             
             
               141i 
               seat rim of first inlet valve seat 111i 
             
             
               141o 
               seat rim of first outlet valve seat 111o 
             
             
               151i 
               chamber channel for fluid communication between left pump 
             
             
                 
               chamber cavity 113l and first inlet valve seat 111i 
             
             
               151o 
               chamber channel for fluid communication between left pump 
             
             
                 
               chamber cavity 113l and first outlet valve seat 111o 
             
             
               152i 
               chamber channel for fluid communication between right pump 
             
             
                 
               chamber cavity 113r and second inlet valve seat 112i 
             
             
               152o 
               chamber channel for fluid communication between right pump 
             
             
                 
               chamber cavity 113r and second outlet valve seat 112o 
             
             
               156 
               transverse segment of manifold A in process fluid body 110 
             
             
               157 
               transverse segment of manifold B in process fluid body 110 
             
             
               160l 
               left motive fluid plate 
             
             
               160r 
               right motive fluid plate 
             
             
               161i 
               transfer passage of manifold A between actuation cavity 171i of 
             
             
                 
               first outlet valve 101i and segment 168r 
             
             
               161o 
               transfer passage of manifold B between actuation cavity 171o of 
             
             
                 
               first outlet valve 101o and segment 164r 
             
             
               162i 
               transfer passage of manifold B between actuation cavity 172i of 
             
             
                 
               second inlet valve 102i and segment 168l 
             
             
               162o 
               transfer passage of manifold A between actuation cavity 172o of 
             
             
                 
               second outlet valve 102o and segment 164l 
             
             
               163l 
               transfer passage of manifold A between actuation cavity 173l of 
             
             
                 
               left pump chamber 103l and segment 164l 
             
             
               163r 
               transfer passage of manifold B between actuation cavity 173r of 
             
             
                 
               left pump chamber 103r and segment 164r 
             
             
               164l 
               segment of manifold A 
             
             
               164r 
               segment of manifold B 
             
             
               165l 
               segment of manifold A 
             
             
               165r 
               segment of manifold B 
             
             
               166l 
               segment of manifold A 
             
             
               166r 
               segment of manifold A 
             
             
               167l 
               segment of manifold B 
             
             
               167r 
               segment of manifold B 
             
             
               168l 
               segment of manifold B 
             
             
               168r 
               segment of manifold A 
             
             
               169l 
               segment of manifold B 
             
             
               169r 
               segment of manifold A 
             
             
               171i 
               actuation cavity of first inlet valve 101i 
             
             
               171o 
               actuation cavity of first outlet valve 101o 
             
             
               172i 
               actuation cavity of second inlet valve 102i 
             
             
               172o 
               actuation cavity of second outlet valve 102o 
             
             
               173l 
               actuation cavity of left pump chamber 103l 
             
             
               173r 
               actuation cavity of right pump chamber 103r 
             
             
               181i 
               recess of first inlet valve 101i 
             
             
               181o 
               recess of first outlet valve 101o 
             
             
               182i 
               recess of second inlet valve 102i 
             
             
               182o 
               recess of second outlet valve 102o 
             
             
               183l 
               recess of left pump chamber 103l 
             
             
               183r 
               recess of right pump chamber 103r 
             
             
               184 
               cavity surface 
             
             
               185l 
               inclined region 
             
             
               186l 
               rim 
             
             
               187l 
               perimeter linear recess features 
             
             
               188 
               circular recess features 
             
             
               191i&amp;o 
               o-rings 
             
             
               192i&amp;o 
               o-rings 
             
             
               193r&amp;l 
               o-rings 
             
             
               199r&amp;l 
               plugs 
             
             
               266r&amp;l 
               o-rings 
             
             
               267r&amp;l 
               o-rings 
             
             
               256r&amp;l 
               holes in the integrated diaphragm media 
             
             
               257r&amp;l 
               holes in the integrated diaphragm media 
             
             
               270l 
               left integrated diaphragm media 
             
             
               270r 
               right integrated diaphragm media 
             
             
               271i 
               first inlet valve region of right integrated diaphragm media 270r 
             
             
               271o 
               first outlet valve region of right integrated diaphragm media 270r 
             
             
               272i 
               second inlet valve region of left integrated diaphragm media 
             
             
                 
               270l 
             
             
               272o 
               second outlet valve region of left integrated diaphragm media 
             
             
                 
               270l 
             
             
               273l 
               first pump chamber region of left integrated diaphragm media 
             
             
                 
               270r 
             
             
               273r 
               second pump chamber region of right integrated diaphragm 
             
             
                 
               media 270r 
             
             
               300 
               forming fixture 
             
             
               310 
               first plate 
             
             
               320 
               chamber region face 
             
             
               322 
               o-ring groove 
             
             
               324 
               portal 
             
             
               326 
               perimeter of chamber region face 
             
             
               330a-b 
               valve region faces 
             
             
               332a-b 
               o-ring grooves 
             
             
               334a-b 
               portals 
             
             
               336a-b 
               perimeters of valve region faces 
             
             
               340 
               second plate 
             
             
               350 
               chamber region recess 
             
             
               352 
               recess surface 
             
             
               354 
               portal 
             
             
               356 
               lip 
             
             
               358 
               rim portion 
             
             
               360a-b 
               valve region recesses 
             
             
               362a-b 
               recess surfaces 
             
             
               364a-b 
               portals 
             
             
               366a-b 
               lips 
             
             
               368a-b 
               rim portions 
             
             
                 
             
          
         
       
     
   
   DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
   The inventions described hereinafter relate to a pump apparatus and related methods and systems.  FIG. 5  provides a schematic view of one embodiment of a system utilizing the double diaphragm pump. Another embodiment of a double diaphragm pump and another embodiment of a system which utilizes the pump are shown in the schematic view provided in  FIG. 7 .  FIGS. 9A-9B  and  FIGS. 10A-10D  relate to an embodiment of a forming fixture used to shape regions of a diaphragm media which is used in the pump. 
   The pump enables fluids to be transferred in a wide variety of fields. For example, the pump can be used in the transfer of high purity process fluids which may be corrosive and/or caustic in the manufacture of semiconductor chips. The pump is advantageous in transferring high purity process fluids as the pump avoids or at least minimizes the introduction or generation of contaminants or particulate matter that can be transferred downstream by reducing or eliminating rubbing and sliding components. Downstream transfer of contaminants or particulate matter may eventually damage or contaminate the high-purity finished product such as a semiconductor chip or shorten the durability of filters placed downstream of pumps. 
   The double diaphragm pump also has medical uses. For example, the pump can be used to move blood. Particulates generated by pumps moving fluids to and from a patient have the potential to create adverse health effects. These include the generation of embolisms or microembolisms in the vascular system and also the toxicity of the materials introduced or generated by the pump. Additionally, using a pneumatically actuated diaphragm pump is advantageous because of the inherent control of delivering fluids within biologically acceptable pressure ranges. If a blockage occurs in the process fluid connection lines to the pump, the pump will only generate pressure in the process fluid at or near the pneumatic supply pressures driving the pump. In the case of pumping blood, excessive pressures or high vacuums can damage blood or cause air embolisms. 
     FIG. 1  provides a perspective of one embodiment of a double diaphragm pump at  100 .  FIG. 1  also shows process fluid body  110 , left motive fluid plate  160   l  and right motive fluid plate  160   r . The integrated diaphragm media between process fluid body  110  and each of the plates are not shown in  FIG. 1  but are shown in  FIG. 2  and  FIGS. 4B-4C . While the integrated diaphragm media do not necessarily extend to the perimeter of process fluid body  110 , plate  160   l  and plate  160   r , in an another embodiment the media can extend to the perimeter or beyond so that the media protrudes. 
     FIG. 1  also shows features related to the inlet and outlet lines for the process fluid in process fluid body  110 . In particular, inlet line  130   i  within inlet line extension  138   i  and outlet line  130   o  within outlet line extension  138   o  are shown. Line  130   i  and line  130   o  are shown in more detail in  FIG. 3B ,  FIGS. 4B-4C  and  FIG. 4F . In this embodiment, connections to external process fluid lines can be made to the inlet line extension  138   i  and outlet line extension  138   o.    
   Some of the components which comprise the valve chambers and the pump chambers are shown in  FIG. 2 , however, the chambers are not identified in  FIG. 2  as it is an exploded perspective view. The chambers are identified in  FIGS. 4B-4C , FIGS.,  4 E- 4 G,  FIG. 5  and  FIG. 7 . The chambers include first inlet valve chamber  101   i , first outlet valve chamber  101   o , second inlet valve chamber  102   i , second outlet valve chamber  102   o , left pump chamber or first pump chamber  103   l , and right pump chamber or second pump chamber  103   r . Assembling the components together shown in  FIG. 2  can be done by mechanical fasteners such as nuts and bolts, clamps, screws, etc.; adhesives; welding; bonding; or other mechanisms. These mechanisms are all examples of means for maintaining the plates and body together and sealing chambers created between the plates and body. 
     FIG. 2  provides the best view of left integrated diaphragm media  270   l  and right integrated diaphragm media  270   r . Each media has a specific region corresponding with a particular chamber. In one embodiment, the regions are pre-shaped. For example, the regions may be pre-shaped by stretching. Of course, each chamber could also use a separate diaphragm that is not integrated instead of a single diaphragm media. Additionally, the separate diaphragms could also be pre-formed or pre-stretched. Methods for forming an integrated diaphragm media with pre-shaped regions is discussed below with reference to  FIGS. 9A-9B  and  FIGS. 10A-10D . 
   The chamber regions of left integrated diaphragm media  270   l  include second inlet valve region  272   i , second outlet valve region  272   o  and first pump chamber region  273   l . The chamber regions of right integrated diaphragm media  270   r  include first inlet valve region of  271   i , first outlet valve region  271   o  and second pump chamber region  273   r . Each media also has a hole  256   r  ( 256   l ) and a hole  257   r  ( 257   l ) for passage of the motive fluid via manifold A and manifold B.  FIG. 2  also shows a plurality of optional o-rings  191   i ,  191   o ,  192   i ,  192   o ,  193   l ,  193   r ,  266   r ,  266   l ,  267   r , and  267   l  which assist in sealing each valve chamber, pump chamber, and the passages for the motive fluids. 
   Left/first pump chamber  103   l  is divided by first pump chamber region  273   l  into left pump chamber cavity  113   l  and actuation cavity  173   l . Similarly, right/second pump chamber  103   r  is divided by second pump chamber region  273   r  into right pump chamber cavity  113   r  and actuation cavity  173   r . Each of the valve chambers  101   i ,  101   o ,  102   i  and  102   o  are also divided by their respective diaphragm media regions. In particular, valve chambers  101   i ,  101   o ,  102   i  and  102   o  each comprise an actuation cavity and a valve seat. The valve seats include first inlet valve seat  111   i , first outlet valve seat  111   o , second inlet valve seat  112   i , and second outlet valve seat  112   o . The actuation cavities include actuation cavity  171   i  of first inlet valve  101   i , actuation cavity  171   o  of first outlet valve  101   o , actuation cavity  172   i  of second inlet valve  102   i  and actuation cavity  172   o  of second outlet valve  102   o.    
   The flow path of the fluids in double diaphragm pump  100  are described below with reference to  FIG. 5  and  FIG. 7 . The flow path is also described with reference to  FIGS. 4B-4C . Before providing a comprehensive overview of the flow path, the components of double diaphragm pump  100  are described below with occasional reference to the flow path. However, it should be understood that a process fluid is pumped into and out of left/first pump chamber  103   l  and right/second pump chamber  103   r  so that the fluid enters and exits process fluid body  110 . It should also be understood that the different regions of the diaphragm media are moved by alternating applications of pressure and vacuums via a motive fluid in manifold A and manifold B to pump the process fluid into and out of pump chambers  103   l  and  103   r.    
   Note that the different regions of the diaphragm media can also be moved by applying a pressure to the motive fluid which is greater than the pressure of the process fluid and alternating with application of pressure of the motive fluid which is less than the pressure of the process fluid. The amount of pressure or vacuum applied can vary significantly depending on the intended use. For example, it may be used to deliver a fluid at a pressure in a range from about 0 psig to about 2000 psig, 1 psig to about 300 psig, 15 psig to 60 psig. Similarly, it may receive fluid from a source or generate suction in a range from about −14.7 psig to about 0 psig or an amount which is less than the pressure of the fluid source. In an embodiment used as a blood pump, it can deliver or receive blood at a pressure ranging from about −300 mmHg to about 500 mmHg. 
     FIG. 3A ,  FIG. 4B , and  FIG. 4C  shows actuation cavity  172   i  of second inlet valve  102   i , actuation cavity  172   o  of second outlet valve  102   o  and actuation cavity  173   l  of left pump chamber  103   l .  FIG. 3A  also shows portions of manifold A and manifold B. As best understood with reference to  FIG. 4B  and  FIG. 4G , actuation cavity  173   l  is in fluid communication with actuation cavity  172   o  via manifold A. One of the components of manifold A in left motive fluid plate  160   l  is a transfer passage  163   l  for fluid communication between actuation cavity  173   l  of left pump chamber  103   l  and segment  164   l , which is the long horizontal segment. Another component is a transfer passage  162   o  for fluid communication between actuation cavity  172   o  of second outlet valve  102   o  and segment  164   l . Other components of manifold A in left motive fluid plate  160   l  comprise segment  165   l , which is a long vertical segment extending from segment  164   l , and segment  166   l , which is a short transverse segment extending from segment  165   l  through left motive fluid plate  160   l . Other components of manifold A are in process fluid body  110  and right motive fluid plate  160   r.    
   In addition to showing the components of manifold A in left motive fluid plate  160   l ,  FIG. 3A  also shows the components of manifold B in left motive fluid plate  160   l . As best understood with reference to  FIGS. 4B-4C , the manifold B components comprise segments which extend through left motive fluid plate  160   l  and provide fluid communication to each other. These segments are segment  166   l  (not shown) which extends transversely, segment  169   l  which is a short segment extending vertically and transfer passage  162   i  for fluid communication between actuation cavity  172   i  of second inlet valve  102   i  and segment  168   l.    
   Actuation cavity  172   i  of second inlet valve  102   i , actuation cavity  172   o  of second outlet valve  102   o  and actuation cavity  173   l  of left pump chamber  103   l  each have recess configurations which enables the pressure to be rapidly distributed to a large portion of the surface area of the diaphragm region to pressure. These configurations reduce time lags in the response of the diaphragm when switching from a vacuum in one of the manifolds to pressure. For example, actuation cavities  172   i  and  172   o  each have a recess  182   i  and  182   o . Recesses  182   i  and  182   o  each have a pair of linear recess features opposite from each other which are separated by a circular recess feature. The linear features of recess  182   i  are identified at  188   i  and the circular recess feature is identified at  189   i . The recess features of recess  182   o  are similarly identified. 
   Recess  183   l  comprises a plurality of recess features. Recess  183   l  of actuation cavity  173   l  has a larger configuration than recesses  182   i  and  182   o . Also, cavity surface  184   l  is not just around recess  183   l  but is also at the center of recess  183   l  for wide distribution of the pressure or vacuum. Like actuation cavities  172   i  and  172   o , actuation cavity  173   l  also has an inclined region as identified at  185   l . Rim  186   l  and perimeter  187   l ; sealing features  195   i ,  195   o , and  196   l ; and plugs  199   l  are also identified in  FIG. 3A  (plugs  199   r  are identified in  FIG. 4E ). 
     FIG. 3B  shows one side of process fluid body  110  with the other side shown in phantom. Left pump chamber cavity  113   l , second inlet valve seat  112   i  and second outlet valve seat  112   o  are shown while right pump chamber cavity  113   r , first inlet valve seat  111   i , and first outlet valve seat  111   o  are shown in phantom. Each valve seat has a groove  121   i  ( 121   o ) around a rim  141   i  ( 141   o ). A valve portal  131   i  ( 131   o ) provide fluid communication between each valve seat and its corresponding line. For example, inlet line  130   i  which is shown in phantom is in fluid communication with first inlet valve portal  131   i  and second inlet valve portal  132   i . Similarly, outlet line  130   o  which is also shown in phantom, is in fluid communication with first outlet valve portal  131   o  and second outlet valve portal  132   o.    
   Chamber channels  151   i  and  151   o  provide fluid communication respectively with first inlet valve seat  111   i  and left pump chamber cavity  113   l  and with first outlet valve seat  111   o  and left pump chamber cavity  113   l . Similarly fluid communication with right pump chamber cavity  113   r  between second inlet valve seat  111   i  and second outlet valve seat  112   o  is achieved respectively via chamber channels  152   i  and  152   o . This configuration permits first inlet valve seat  111   i  and second inlet valve seat  112   i  to be in fluid communication with inlet line  130   i  and to alternatively receive the process fluid. Similarly, first outlet valve seat  111   o  and second outlet valve seat  112   o  are in fluid communication with outlet line  130   o  and alternatively deliver the process fluid. 
     FIG. 3B  also shows other features of the pump chamber cavities  113   l  and  113   r . The surface of each pump chamber cavity is identified respectively at  114   r  and  114   l  with an inclined region identified at  115   l  and  115   r . Grooves (not shown) may be incorporated in the pump chamber cavities  113   l  and  113   r  to provide flow channels that enhance the discharge of the process fluid from the pump chambers when the integrated diaphragm media  270   l  and  270   r  is in proximity of the surface of the pump chamber cavities. A rim  116   r  ( 116   l ) and perimeter  117   r  ( 117   l ) are also identified. The perimeters of the valve seats are also shown in  FIG. 3B . The perimeter of first inlet valve seat  111   i  and the first outlet valve seat  111   o  are respectively identified at  118   i  and  118   o . The perimeter of second inlet valve seat  112   i  and the second outlet valve seat  112   o  are respectively identified at  119   i  and  119   o . Note that the transition from the inclined regions to the rims is rounded. These rounded transitions limit the mechanical strain induced in the flexing and possible stretching of the diaphragm regions for a longer cyclic life of the integrated diaphragm media. 
     FIG. 3B  also shows the components of manifolds A &amp; B in process fluid body  110 . Segment  156  of manifold A and segment  157  of manifold B both extend transversely through fluid body  110 . Segment  156  is in fluid communication with segment  166   l  of left motive fluid plate  160   l  and  166   r  of right motive fluid plate  160   r . Segment  157  is in fluid communication with segment  167   l  of left motive fluid plate  160   l  and  167   r  of right motive fluid plate  160   r.    
     FIG. 3C  is a perspective view of right motive fluid plate  160   r  which shows manifold A and manifold B in phantom.  FIG. 3C  shows actuation cavity  171   i  of first inlet valve  101   i , actuation cavity  171   o  of first outlet valve  101   o  and actuation cavity  173   r  of right pump chamber  103   r . As best understood with reference to  FIG. 4B , actuation cavity  173   r  is in fluid communication with actuation cavity  171   o  via manifold B. Right motive fluid plate  160   r  has an identical configuration as left motive fluid plate  160   l  so all of the features of right motive fluid plate  160   r  are not specifically identified in  FIG. 3C . Note, however, that the features of right motive fluid plate  160   r  are more specifically identified in  FIGS. 4B-4C  and  FIG. 4E . 
     FIGS. 4B-4C  are transverse cross-sectional views taken along the cutting lines shown in  FIG. 4A  to show the operation of first inlet valve chamber  101   i , first outlet valve chamber  101   o , second inlet valve chamber  102   i , second outlet valve chamber  102   o , left pump chamber  103   l , and right pump chamber  103   r  via manifold A and manifold B.  FIGS. 4B-4C  also show the operation of left integrated diaphragm media  270   l  and right integrated diaphragm media  270   r.    
     FIG. 4B  shows first inlet valve chamber  101   i , first outlet valve chamber  101   o  and left pump chamber  103   l . In  FIG. 4B , the left integrated diaphragm media  270   l  and right integrated diaphragm media  270   r  are shown at the end of their flexing strokes where pressure is being applied in manifold A while a vacuum is applied in manifold B. Pressure in manifold A prevents fluid communication via chamber channel  151   i  between first inlet valve chamber  101   i  and left pump chamber  103   l  by flexing first inlet valve region  271   i  of right integrated diaphragm media  270   r . Simultaneously, pressure in manifold A drives against left pump chamber region  273   l  of left integrated diaphragm media  270   l  and forces the process fluid through chamber channel  151   o , as identified in  FIG. 3B , into first outlet valve chamber  101   o , and then out of pump  100  via outlet line  130   o . As shown in  FIG. 4C , the pressure in manifold A also prevents fluid communication via chamber channel  152   o  between second outlet valve chamber  102   o  and right pump chamber  103   r.    
     FIG. 40  shows second inlet valve chamber  102   i , second outlet valve chamber  102   o  and right pump chamber  103   r . As indicated above,  FIGS. 4B-4C  show the simultaneous application of pressure in manifold A and a vacuum in manifold B in different cross-sectional views. The vacuum in manifold B pulls right pump chamber region  273   r  of right integrated diaphragm media  270   r  against the surfaces  184   r  of actuation cavity  173   r  via recess  183   r . The vacuum in manifold B also pulls second inlet valve region  272   i  of left integrated diaphragm media  270   l  into second inlet valve chamber  102   i . By pulling second inlet valve region  272   i , fluid communication is provided for the process fluid from inlet line  130   i , into second inlet valve chamber  102   i , through chamber channel  152   i  and then into right pump chamber  103   r . The vacuum in manifold B also pulls first outlet valve region  271   o  into first outlet valve chamber  101   o  so that the process fluid passes more easily from chamber channel  151   o , into first outlet valve chamber  101   o , and then into outlet line  130   o.    
     FIGS. 4E-4G  are longitudinal cross-sectional views taken along the cutting lines shown in  FIG. 4D  which depict manifold A, manifold B and the lines for the process fluid. As shown, pressure or a vacuum is simultaneously applied to the diaphragm regions in left pump chamber  103   l , first inlet valve chamber  101   i , and second outlet valve chamber  102   o . Also simultaneously, manifold A receives the opposite of the pressure or vacuum being applied in manifold B. Manifold B then causes pressure or a vacuum to be applied to the diaphragm regions in right pump chamber  103   r , first outlet valve chamber  101   o , and second inlet valve chamber  102   i . While the components linked to manifold A and manifold B may be simultaneously operated they may also be independently controlled such that they are not operated at opposite pressures. 
     FIG. 5  provides a schematic view which shows the connections between the valves and the pump chambers.  FIG. 5  also shows the first and second motive fluids respectively as a pressure source  20  and a vacuum source or vent  30 .  FIG. 5  also shows that the motive fluids are in fluid communication with pump  100  via valve  10 . The vacuum source or vent is at a pressure that is less than the process liquid source pressure to allow intake of the process fluid into the pumping chambers. The motive fluid pressures can be selectively controlled by pressure regulators (not shown in  FIG. 5 ) or other devices to the desired pressures needed to pump the process fluid. Valve  10  is controlled by an electric or pneumatic controller  12 . By restricting the process fluid discharge and cycling the control valve  10  to cyclically apply pressure and vacuum to manifolds A and B prior to the integrated diaphragm media reaching the end of stroke or pump chamber surface  114   r  and  114   l , the process liquid pressure and flow is substantially maintained. A process liquid source  38  is also shown coupled to inlet line extension  138   i . An example of a first motive fluid is compressed air at a first pressure such as 30 psig (pounds per square inch gage) pressure and an example of a second motive fluid is air at a second pressure such as −5 psig vacuum pressure. 
     FIG. 5  shows the flow paths of the motive fluid. Manifold A is shown having fluid communication with the first inlet valve or more particularly, first inlet valve chamber  101   i ; the second outlet valve or more particularly, second outlet valve chamber  102   o  and also actuation cavity  173   l  of left pump chamber  103   l . Manifold B is shown in fluid communication with the first outlet valve or more particularly, first outlet valve chamber  101   o ; the second inlet valve or more particularly, second inlet valve chamber  102   i  and also to actuation cavity  173   r  of right pump chamber  103   r.    
   Fluid communication is also in  FIG. 5  with regard to the process fluid. Left pump chamber cavity  113   l  is in fluid communication with first inlet valve chamber  101   i  and first outlet valve chamber  101   o . Right chamber cavity  113   r  is in fluid communication with second inlet valve chamber  102   i  and second outlet valve chamber  102   o.    
   A flow restrictor  380  is shown outside of pump  100  in  FIG. 5  coupled to outlet line extension  138   o . The embodiment of pump  100 ′ shown in  FIG. 7  differs from pump  100  in that the flow restrictor  380  is within pump  100 ′. The flow restrictor is a passage which has a smaller cross-section area than an upstream cross-sectional area. The flow restrictor prevents the process fluid from discharging from the pump  100  faster than pump chambers can be cycled to be suction filled and pressure discharged creating a substantially continuous flow. 
   The embodiment of the system shown in  FIG. 7  also differs from the embodiment shown in  FIG. 5  as it uses two valves  10   a  and  10   b  which separately control the pressure and suction applied to manifold A and manifold B.  FIG. 6  shows the pressures and vacuums experienced by manifold A and manifold B when a single valve is used as shown in  FIG. 5 .  FIG. 8  shows the pressures and vacuums experienced by manifold A and manifold B when two valves are used as shown in  FIG. 7 . By contrasting the graphs shown in  FIG. 6  and  FIG. 8 , it is apparent that the discharge pressure droop during the cycle shift is reduced. This droop is caused by the time required to switch a single valve from one position to another. This droop is reduced through the use of two valves. 
   All of the double diaphragm pump components exposed to process fluids can be constructed of non-metallic and/or chemically inert materials enabling the apparatus to be exposed to corrosive process fluids without adversely changing the operation of the double diaphragm pump. For example, the fluid body  110 , left motive fluid plate  160   l  and right motive fluid plate  160   r  may be formed from polymers or metals depending on the material compatibility with the process fluid. Diaphragm media may be formed from a polymer or an elastomer. An example of a suitable polymer that has high endurance to cyclic flexing is a fluorpolymer such as polytetrafluoroethylene (PTFE), polyperfluoroalkoxyethylene (PFA), or fluorinated ethylene propylene (FEP). 
   In the depicted embodiments, the pre-formed regions of right integrated diaphragm media  270   r  namely, first inlet valve region  271   i , first outlet valve region  271   o  and second pump chamber region  273   r  and the pre-formed regions of left integrated diaphragm media  270   l  namely, second inlet valve region  272   i , second outlet valve region  272   o  and first pump chamber region  273   l , which are formed from a film with a uniform thickness. The thickness of the diaphragm media may be selected based on a variety of factors such as the material, the size of the valve or chamber in which the diaphragm moves, etc. Since the diaphragms only isolate the motive fluid from the process fluid when they are not at an end of stroke condition and are intermittently supported by the pump chamber cavities when at end of stroke conditions, the diaphragm media thickness is only required to sufficiently isolate the process fluid from the motive fluid and to have enough stiffness to generally maintain its form when pressurized against features in the pump cavities. When flexing to the same shape, a thin diaphragm has a lower level of mechanical strain when cycled than a thicker diaphragm. The lower cyclic strain of a thin diaphragm increases the life of the diaphragm before mechanical failure of the material. In one embodiment, the diaphragm media has a thickness in a range from about 0.001″ to about 0.060″. In another embodiment, the diaphragm media has a thickness in a range from about 0.005″ to about 0.010″. 
     FIG. 9A  depicts a diaphragm media  270  before the regions have been pre-formed or pre-stretched. The diaphragm media has been cut from a sheet of film. Diaphragm media has a uniform thickness and is then shaped to yield pre-formed or pre-stretched regions.  FIG. 9B  depicts right integrated diaphragm media  270   r  as it appears after diaphragm media  270  has been pre-formed or pre-stretched in forming fixture  300  as shown in  FIGS. 10A-10D . 
   While  FIGS. 10A-10D  depict the use of diaphragm media  270  to form right integrated diaphragm media  270   r , forming fixture  300  can also be used to form left integrated diaphragm media  270   l .  FIGS. 10A-10D  depict the use of pressure or vacuum to shape the regions of the diaphragm media. Heat could also be used separately or in addition to the vacuum or pressure used to form the regions in the diaphragm media. 
     FIG. 10A  depicts first plate  310  and second plate  340  of forming fixture  300  in an exploded view. Because forming fixture  300  is shown being used to produce a right integrated diaphragm media  270   r  from diaphragm media  270 , the o-rings depicted include o-rings  191   i ,  191   o  and  193   r.    
   First plate  310  is shown in  FIG. 10A  with a chamber region face  320  and valve region faces  330   a  and  330   b . Chamber region face  320  is circumscribed by o-ring groove  322 . Valve region faces  330   a  and  330   b  are respectively circumscribed by o-ring grooves  332   a - b . The other surface area of the top of first plate  310  is referred to herein as the face of first plate  310 . Face  320  has a portal  324  and faces  330   a - b  have respective portals  334   a - b.    
     FIG. 10B  shows fixture  300  with diaphragm media  270  between first plate  310  and second plate  340 . Fixture  300  includes chamber region recess  350  and valve region recess  360   b . The fixture  300  can be clamped together with mechanical fasteners or other assembly mechanisms to hold the diaphragm media  270  in position and to withstand the pressure required to pre-form or pre-stretch the diaphragm media  270 . Pressure has not yet been delivered via portals  324  and  334   a - b  so diaphragm media  270  is shown resting and sealed between faces  320  and  330   a - b  and the remainder of the face of first plate  310 . 
   Second plate  340  has chamber region recess  350  with a recess surface  352  and a portal  354 . Second plate  340  also has valve regions with recesses  360   b  with respective recess surfaces  362   b  and portals  364   b . Each recess surface is defined by a lip as identified at  356  and  366   b . In this embodiment, each lip is essentially the portion of the face of second plate  340  around the respective recesses. Diaphragm media  270  is circumferentially held between perimeter  326  and lip  356 , perimeter  336   a  and lip  366   a , and perimeter  336   b  and lip  366   b , so that the circumscribed regions of diaphragm media  270  can be directed toward recess surfaces  352  and  362   a - b . Each recess surface has a rim portion which is the transition to the lip. The rim portions are identified at  358  and  368   b.    
     FIG. 10C  shows pressure or a vacuum being used to form regions in right integrated diaphragm media  270   r  namely, first inlet valve region  271   l  and second pump chamber region  273   r .  FIGS. 10B-10D  do not depict the formation of first outlet valve region  271   o  due to the orientation of cut line  10 B- 10 B but it is formed in the same way as first inlet valve region  271   i . Diaphragm media  270  becomes right integrated diaphragm media  270   r  as region  273   r  is driven against recess surface  352 , region  271   i  is driven against recess surface  362   b , and region  271   o  is driven against recess surface  362   a . Note that the rim portions  358  and  368   b  may be configured to yield regions as shown in  FIG. 9B  with inner perimeters and outer perimeters. 
   Regions  271   i ,  271   o  and  273   r  are formed in fixture  100  using a differential pressure that exceeds the elastic limit of the diaphragm material. Pressure may be delivered via portals  324  and  334   a - b , a vacuum may be applied via portals  354  and  364   a - b  and a combination of both pressure and a vacuum may be used to stretch the regions of the diaphragm media. The differential pressure stretches the regions of diaphragm media  270  so that when the differential pressure is removed, the stretched regions have a particular cord length. The cord length is sufficient to enable the diaphragm regions to flex and pump the fluid in the pump chamber and to flex and controllably seal the fluid flow through the pump valves at the same pressures. By pre-forming the regions of the diaphragm media, additional pressure is not required to seat the valve regions as compared with the pressure required for movement of the region of the diaphragm in the pump chamber. Additionally by controlling the cord length of the diaphragm media  270 , the mechanical cycle life of the diaphragm is increased by minimizing material strain when flexing from one end of stroke condition to the other end of stroke condition and stretching of the material is not required for the diaphragm to reach the end of stroke condition. 
     FIG. 10D  depicts right integrated diaphragm media  270   r  after the formation of first inlet valve region  271   i  and second pump chamber region  273   r . As mentioned above, first outlet valve region  271  is not shown in  FIG. 10D . Pre-stretching the valve regions of the integrated diaphragm media and the chamber regions enables the valve regions to be seated and the chamber regions to move fluid into and out of the chambers based only on sufficient pressure (positive or negative) for movement of the regions. Stated otherwise, after these regions have been formed by stretching the diaphragm media, the regions move in response to fluid pressure with essentially no stretching as each valve or chamber cycles via movement of the diaphragm regions. In one embodiment, the diaphragm regions are sufficiently pre-stretched so that the cord length of the valve regions and the chamber regions remains constant while cycling. In another embodiment, there is essentially no stretching which means that the cord length changes less than 5% during each pump cycle. Since pressure is applied only for movement either exclusively or for movement and at most a nominal amount for stretching the pre-formed regions, the amount of pressure is low and the lifespan of the diaphragm media is extended due to the gentler cycling. Since material strain is reduced using thin film materials in the construction of the flexing diaphragm media  270  and in-plane stretching of the diaphragm media is controlled by the support of the pump cavities at end of stroke conditions, long mechanical life of diaphragms can be achieved. 
   In alternative embodiments, the double diaphragm pump can be constructed with the inlet and outlet valve chambers and pump chambers located on the same side of the process fluid body. The pump chambers can also be located on the same side of process fluid body while the inlet and outlet valve chambers can be located on the opposite side of the process fluid body. The process fluid body can be constructed with more than two pump cavities, more than two inlet valves, and more than two outlet valves to cooperatively work in pumping a single fluid. Also, multiple double diaphragm pumps can be constructed on a single process fluid body. The integrated diaphragm media can also have more valve regions and pump chamber regions than those shown in the depicted embodiments. 
   Without further elaboration, it is believed that one skilled in the art can use the preceding description to utilize the invention to its fullest extent. The examples and embodiments disclosed herein are to be construed as merely illustrative and not a limitation of the scope of the present invention in any way. It will be apparent to those having skill in the art that changes may be made to the details of the above-described embodiments without departing from the underlying principles of the invention. In other words, various modifications and improvements of the embodiments specifically disclosed in the description above are within the scope of the appended claims. Note that elements recited in means-plus-function format are intended to be construed in accordance with 35 U.S.C. §112 ¶6. The scope of the invention is therefore defined by the following claims.