Check Valve and Diaphram Pump

Abstract

[Problem] To provide a check valve and a diaphragm pump employing the same which has a good response, and in which a valve chamber can be made small so as to be hardly influenced by bubbles. [Means for Solution] A check valve includes a valve chamber 11 which is defined by a top wall 8 having an introducing port 8 a of a fluid, a bottom wall 9 having an exhaust port 9 a of the fluid, and a side wall, and a valve body 12 a which is supported in the valve chamber 11 in a cantilever manner having its base end fixed to the side wall and its distal end formed as a free end, the valve body being arranged above the introducing port 8 a . The bottom wall 9 is formed with a valve seat 9 b having an inclined face 9 b 2 which is inclined so as to be gradually separated from the top wall 8 along the valve body 12 a from the base end toward the distal end thereof. When the valve body 12 a in the cantilever shape moves between the top wall 8 and the valve seat 9 b , the valve body 12 a is restricted by the valve seat 9 having the inclined face 9 b 2 , at opening and closing operation of the valve body 12 a , whereby a moving amount of the valve body 12 a becomes smaller, and response time from an open state to a closed state becomes shorter.

1 . A check valve comprising: 
 a valve chamber which is defined by a top wall having an introducing port of a fluid, a bottom wall having an exhaust port of the fluid, and a side wall; and    a valve body which is supported in the valve chamber in a cantilever manner, the valve body having a base end fixed to the side wall and a distal end as a free end, the valve body being arranged above the introducing port,    wherein the bottom wall includes a valve seat having an inclined face which is inclined so as to be gradually separated from the top wall along the valve body from the base end to the distal end of the valve body, and    wherein the exhaust port is disposed on the valve seat.    
   
   
       2 . The check valve according to  claim 1 , wherein the valve seat includes a groove of which one end is connected to the exhaust port and the other end extends beyond the distal end of the valve body.  
   
   
       3 . The check valve according to  claim 1 , wherein at least one of the introducing port and the exhaust port is disposed at a side of the base end of the valve body.  
   
   
       4 . The check valve according to  claim 1 , wherein the valve body is made of a flexible film.  
   
   
       5 . The check valve according to  claim 1 , further comprising: 
 a first case body having the top wall;    a second case body having the bottom wall; and    a film body having the valve body and sandwiched between the first case body and the second case body,    wherein the first case body includes a convex part,    wherein the second case body includes a concave part to be engaged with the convex part, and    wherein the convex part and the concave part are respectively formed with opposed faces which are parallel to each other and configured to sandwich the base end of the valve body therebetween.    
   
   
       6 . A diaphragm pump comprising: 
 a diaphragm including a piezoelectric element attached thereto;    an upper case body which defines a pressure room in cooperation with the diaphragm therebetween and has an upper intake flow passage and an upper discharge flow passage which are connected to the pressure room; and    a lower case body including a lower intake flow passage which is connected to the upper intake flow passage through an intake side check valve, and a lower discharge flow passage which is connected to the upper discharge flow passage through a discharge side check valve,    wherein each of the intake side check valve and the discharge side check valve is the check valve according to  claim 1 , the exhaust ports are respectively connected to the upper intake flow passage and the lower discharge flow passage, the introducing ports are respectively connected to the upper discharge flow passage and the lower intake flow passage.    
   
   
       7 . The check valve according to  claim 2 , wherein at least one of the introducing port and the exhaust port is disposed at a side of the base end of the valve body.  
   
   
       8 . The check valve according to  claim 2 , wherein the valve body is made of a flexible film.  
   
   
       9 . The check valve according to  claim 2 , further comprising: 
 a first case body having the top wall;    a second case body having the bottom wall; and    a film body having the valve body and sandwiched between the first case body and the second case body,    wherein the first case body includes a convex part,    wherein the second case body includes a concave part to be engaged with the convex part, and    wherein the convex part and the concave part are respectively formed with opposed faces which are parallel to each other and configured to sandwich the base end of the valve body therebetween.