Diaphragm pump and cooling system with the diaphragm pump

Abstract

A diaphragm pump enabling an increase in pump efficiency by reducing the pressure loss of liquid and reduction in thickness. The flow passage in piezoelectric pump ( 1 ) includes a pressure chamber ( 50 ) formed into a flat shape in cross section and a suction side flow passage ( 70 a ) and discharge side flow passage ( 70 b ). The suction side flow passage ( 70 a ) and the discharge side flow passage ( 70 b ) are disposed at both ends of the pressure chamber ( 50 ) so that the axes thereof are aligned with each other. The check valves ( 20 a , 20 b ) are respectively disposed on the suction side flow passage ( 70 a ) and the discharge side flow passage ( 70 b ), and are tilted relative to the flow direction of the liquid.

1 . A diaphragm pump comprising: 
 a pressure chamber formed into a flat shape and is filled up with liquid;    a suction side flow passage and a discharge side flow passage disposed at both ends of the pressure chamber so that axes thereof are aligned with each other and are connected with the pressure chamber;    at least one groove formed in a peripheral wall of the pressure chamber and for accelerating a flow of the liquid downstream in a flow direction; and    at least one diaphragm disposed on at least one of an upper surface and a lower surface of the pressure chamber and for oscillation to make a volume of the pressure chamber variable.    
   
   
       2 . The diaphragm pump according to  claim 1 , wherein the groove has a part with an opening in the upper surface facing the pressure chamber, into which the liquid flows, and a side part with an opening opened to a peripheral wall surface of the pressure chamber, from which the liquid is discharged downstream in the flow direction.  
   
   
       3 . The diaphragm pump according to  claim 1  or  2 , wherein the groove is extended in a radial direction while a point in the vicinity of an entrance of the discharge side flow passage is set as the center.  
   
   
       4 . The diaphragm pump according to any one of claims  1  or  2 , wherein the axes are positioned at the center of a cross-sectional shape of the pressure chamber in a surface orthogonal to the axes.  
   
   
       5 . The diaphragm pump according to any one of claims  1  or  2 , wherein each cross-sectional shape of the pressure chamber, the suction side flow passage, and the discharge side flow passage in a surface orthogonal to the axes are formed in an approximate rectangle.  
   
   
       6 . The diaphragm pump according to  claim 5 , wherein a lower surface of the pressure chamber and the lower surfaces of the suction side flow passage and the discharge side flow passage are formed on the same surface.  
   
   
       7 . The diaphragm pump according to any one of claims  1 ,  2  or  6 , wherein a length of the pressure chamber viewed from an upper surface in a direction orthogonal to the axes is continuously shortened toward the suction side flow passage or the discharge side flow passage.  
   
   
       8 . The diaphragm pump according to any one of claims  1 ,  2  or  6 , wherein a height of the pressure chamber is continuously lowered toward the suction side flow passage or the discharge side flow passage.  
   
   
       9 . The diaphragm pump according to any one of claims  1 ,  2  or  6 , further comprising: 
 check valves, respectively disposed on the suction side flow passage and the discharge side flow passage, at least one of the check valves being tilted relative to a direction of the axes.    
   
   
       10 . The diaphragm pump according to any one of through  9  claims  1 ,  2  or  6 , further comprising: 
 at least one intake opened to an upper surface of the suction side flow passage and to introduce bubbles mixed in the liquid; and    a sealed space connected with the intake and to collect the introduced bubbles.    
   
   
       11 . The diaphragm pump according to  claim 10 , wherein the intake is positioned in the suction side flow passage upstream relative to the check valve.  
   
   
       12 . The diaphragm pump according to any one of claims  1 ,  2 ,  6  or  11 , wherein the diaphragm is a piezoelectric oscillator driven by a piezoelectric element.  
   
   
       13 . A cooling system comprising: 
 the diaphragm pump according to any one of claims  1 ,  2 ,  6  or  11 ; and    a closed-structure flow passage for circulating liquid discharged from the discharge side flow passage in the diaphragm pump and for returning the liquid to the suction side flow passage.