Diaphragm pump

Abstract

A diaphragm pump with a multi-part pump body is described. The pump consists at least of three rigid plates ( 201, 203, 205 ) and at least two elastic diaphragms ( 204, 202 ) arranged between these plates ( 201, 203, 205 ), the plates ( 201, 203, 205 ) forming, in particular, a pumping chamber ( 211 ) and at least two shut-off chambers ( 210, 212 ), in each case with an inlet ( 240 ) and an outlet ( 241 ) orifice for the conveyable material, and the pumping chambers ( 211 ) and shut-off chambers ( 210, 212 ) forming, together with an inlet duct ( 207 ), the connecting ducts ( 208 ) and ( 209 ) and an outlet duct ( 206 ), a passage duct, the pumping chamber ( 211 ) and the shut-off chambers ( 210, 212 ) being separated by the diaphragms ( 204, 202 ) in each case into a product space ( 230, 231, 232 ) and a control space ( 220, 221, 222 ), and the control spaces ( 220, 221, 222 ) having control lines ( 119, 120, 121 ) which are connected to a control unit ( 100, 115 ).

We claim:  
     
         1 . A diaphragm pump comprised of at least three plates, one of which is a middle plate ( 203 ) and two of which are outer plates ( 201 ,  205 ), the middle plate being disposed between the two outer plates, said at least three plates forming at least one pumping chamber ( 211 ), at least two shut-off chambers, said at least two shut-off chambers being a first shut-off chamber ( 210 ) and a second shut-off chamber  212 ), each of said pumping and shut-off chambers being in the form of a spherical segment, a spherical zone, a cylinder or a truncated cone; said middle plate being separated from each of said outer plates by two diaphragms ( 202 ,  204 ) which diaphragms also divide said pumping and shut-off chambers into control spaces ( 220 ,  221 ,  222 ) and product spaces ( 230 ,  231 ,  232 ), the product space ( 231 ) of the pumping chamber being connected to the product space ( 230 ) of said first shut-off chamber ( 210 ) by a first connecting duct ( 208 ) having an orifice ( 241 ) opening into said pumping chamber, and to the product space ( 232 ) of said second shut-off chamber ( 212 ) by a second connecting duct ( 209 ) having an orifice ( 243 ) opening into said second shut-off chamber, with an outlet duct ( 206 ) connected to the product space ( 232 ) of second shut-off chamber ( 212 ) through an outlet orifice ( 244 ), an inlet duct ( 207 ) connected to the product space of first shut-off chamber ( 210 ) through an inlet orifice ( 240 ); said pumping chamber ( 211 ) and shut-off chambers ( 210 ,  212 ), together with outlet duct ( 206 ) and inlet duct ( 207 ), first connecting duct ( 208 ) and second connecting duct ( 209 ) forming a passage duct through said pump, said control spaces ( 220 ,  221 ,  222 ) being connected to a control unit ( 100 ,  115 ) by control lines ( 119 ,  120 ,  121 ).  
     
     
         2 . Diaphragm pump according to  claim 1 , wherein the pump has in product space ( 231 ) a groove ( 213 ) which runs form the vertex of said product space to the outlet orifice.  
     
     
         3 . Diaphragm pump according to  claim 1  wherein pumping chamber ( 211 ) the shut-off chambers ( 210 ,  212 ) are sealed off at their edges by the diaphragms ( 204 ,  202 ).  
     
     
         4 . Diaphragm pump according to  claim 1 , wherein the diaphragms ( 204 ,  202 ) consist of an elastic material selected from the group consisting of elastomers, silicones, Viton® fluroroelastomer, Teflon® polytetrafluoro-ethylene or an EPDM rubber.  
     
     
         5 . Diaphragm pump according  claim 1 , wherein shut-off chambers ( 210 ,  212 ) share a common diaphragm ( 202 ).  
     
     
         6 . Diaphragm pump according  claim 1 , wherein the pump consists of three plates and the pumping chamber ( 211 ) and shut-off chambers ( 210 ,  212 ) are formed by depressions ( 210 ′,  211 ′,  212 ′) in the three plates ( 201 ,  203 ,  205 ).  
     
     
         7 . Diaphragm pump according to  claim 6 , wherein the pump consists of three plates and the pumping chamber ( 211 ) and shut-off chambers ( 210 ,  212 ) are formed by depressions ( 210 ′,  211 ′,  212 ′) in a middle plate ( 203 ′).  
     
     
         8 . Diaphragm pump according to  claim 6 , wherein the pump consists of three plates ( 201 ,  203 ,  205 ) and the pumping chamber ( 211 ) and shut-off chambers ( 210 ,  212 ) are formed by depressions ( 210 ″,  211 ″,  212 ″) in the outer plates ( 201 ″,  205 ″).  
     
     
         9 . Diaphragm pump according to  claim 1 , wherein the center-to-center distance between the respectively adjacent inlet and outlet of the pumping chamber ( 211 ) or of the shut-off chambers ( 210 ,  212 ) is at least twice to ten times the largest hydraulic diameter of said inlet or outlet.  
     
     
         10 . Diaphragm pump according to  claim 1  the control spaces are adapted to be operated by air or hydraulic fluid.  
     
     
         11 . Diaphragm pump according to  claim 1 , further comprising a connecting line which connects the inlet duct ( 207 ) and the outlet duct ( 206 ) and is provided with an overflow valve.  
     
     
         12 . Diaphragm pump according to  claim 1 , wherein the plates ( 201 ,  203 ,  205 ) are releasably held in their positions with respect to one another.  
     
     
         13 . Diaphragm pump according to  claim 1 , wherein the wall of at least one of the control spaces ( 220 ,  221 ,  222 ) which is located opposite the diaphragm ( 202 ,  204 ) has a compensating volume in the form of a depression.  
     
     
         14 . Diaphragm pump according to  claim 13 , wherein said at least one control space is the control space ( 221 ) of the pumping chamber ( 211 ) and said compensating volume is at most 100% of the associated volume of the product space ( 231 ) of said pumping chamber  211 .  
     
     
         15 . Diaphragm pump according to  claim 1 , wherein the projections of the outer contours of the shut-off chambers overlap the outer contours of pumping chambers.  
     
     
         16 . Diaphragm pump according to  claim 1 , wherein the connecting ducts between the pumping chamber ( 211 ′) and the shut-off chambers ( 210 ′,  212 ′) have a ratio of duct length to hydraulic diameter of at most 20.  
     
     
         17 . A pump set, consisting of two or more diaphragm pumps of  claim 1 , wherein the diaphragm pumps have a common control unit ( 100 ,  115 ).  
     
     
         18 . Pump set according to  claim 17 , wherein said at least two diaphragm pumps have common continuous plates ( 201 ,  203 ,  205 ).  
     
     
         19 . Diaphragm pump according to claims  14 , wherein said compensating volume is at most 20% of the volume of said product space.  
     
     
         20 . Diaphragm pump according to  claim 19 , wherein said compensating volume is at most 10% of said volume of said product space.  
     
     
         21 . Diaphragm pump according to  claim 16 , wherein said ratio is at most 10.  
     
     
         22 . Diaphragm pump of  claim 22 , wherein said ratio is at most 5.