Diaphragm pump guaranteed with operational reliability

Abstract

Provided is a diaphragm pump guaranteed with operational reliability that enables a fluid to be continuously sucked and discharged by causing a volume change of an working chamber through a diaphragm pulsating according to the flow of compressed air controlled by movement of a spool constituting an air control valve, and smoothly can pump a fluid by reliably controlling the flow of compressed air using an up-and-down motion of a spool performed by pressure of the compressed air, and thus completely resolving an inoperative situation caused by a delay in motion of the spool. The diaphragm pump includes: a pump body ( 10 ), a shaft ( 20 ), a first diaphragm ( 30 ), a second diaphragm ( 40 ), and an air control valve ( 50 ).

1 . A diaphragm pump guaranteed with operational reliability, comprising:
 a pump body ( 10 ) having a discharge pipe ( 16 ) and a suction pipe ( 17 ) installed at an upper side and a lower side thereof, respectively, provided with an exhaust port ( 18 ) opening to the outside, and divided into a first working chamber ( 14 ) and a second working chamber ( 15 ) connected to the suction pipe ( 17 ) and the discharge pipe ( 16 ) of the left and right, respectively;   a shaft ( 20 ) installed to be movable to the left or right of the pump body and having one end and the other end configured to protrude to the interior of the first working chamber ( 14 ) and the second working chamber ( 15 ), respectively;   a first diaphragm ( 30 ) and a second diaphragm ( 40 ) installed at one end and the other end of the shaft ( 20 ) respectively, and for dividing the first working chamber ( 14 ) into a first fluid chamber ( 14   a ) and a first air chamber ( 14   b ), and the second working chamber into a second air chamber ( 15   b ) and a second fluid chamber ( 15   a ),   respectively; and   an air control valve ( 50 ) including a valve body installed at the pump body ( 10 ) and provided with an air inlet ( 51   a ), and a spool ( 52 ) installed to be vertically movable at an inner side of the valve body ( 51 ) and for controlling the flow of compressed air entering and exiting from the first air chamber ( 14   b ) and the second air chamber ( 15   b ),   wherein the air control valve ( 50 ) is configured such that when the shaft is completely moved to the right or left while the first air chamber ( 14   b ) or the second air chamber ( 15   b ) is filled with compressed air, the compressed air of the first air chamber ( 14   b ) or the second air chamber ( 15   b ) flows in a lower space or an upper space of the valve body ( 51 ) through a first air outflow passage ( 53 ) or a second air outflow passage ( 54 ) to enable a lifting or lowering motion of the spool ( 52 ) to be performed,   
       whereupon the compressed air, which has already entered in the upper space or the lower space of the valve body ( 51 ), along with the compressed air of the first air chamber or the second air chamber are discharged through the exhaust port ( 18 ) to the outside, and at the same time, new compressed air entering from the air inlet ( 51   a ) flows in the second air chamber ( 15   b ) or the first air chamber ( 14   b ), so that a fluid is sucked in the first fluid chamber ( 14   a ) or the second fluid chamber ( 15   a ) by making the first diaphragm ( 30 ) and the second diaphragm ( 40 ) pulsate to the right or left along the shaft, thereby ensuring continuous pumping of the fluid according to discharge of the fluid sucked in the second fluid chamber ( 15   a ) or the first fluid chamber ( 14   b ). 
     
     
         2 . The diaphragm pump of  claim 1 , wherein the spool ( 52 ) has a plurality of protruding flanges ( 52   a ) formed to protrude on an outer circumferential surface thereof while having an up and down distance so as to be divided into: a first pressure space ( 51   b ) whose upper space is an inner side of the valve body ( 51 ); a second pressure space  51   c  whose lower space is the inner side of the valve body ( 51 ); a first exhaust space  51   d  for communicating the first air chamber ( 14   b ) and the exhaust port ( 18 ); a second exhaust space ( 51   e ) for communicating the second air chamber ( 15   b ) and the exhaust port ( 18 ); and an inflow space ( 51   f ) for communicating the first air chamber ( 14   b ) and the second air chamber ( 15   b ) with the air inlet ( 51   a ), wherein an O-ring being in close contact with an inner circumferential surface of the valve body ( 51 ) and for enabling the divided spaces to be sealed is installed at an outer side of the protruding flanges ( 52   a ). 
     
     
         3 . The diaphragm pump of  claim 2 , wherein the first air outflow passage ( 53 ) and the second air outflow passage ( 54 ) are provided between a shaft hole ( 19 ) into which the shaft ( 20 ) is inserted and the shaft  20  and may be opened by a first opening and closing means or a second opening and closing means when the shaft ( 20 ) is fully moved to the right or left so that the first air chamber ( 14   b ) and the second air chamber ( 15   b ) can open onto the second pressure space ( 51   c ) and the first pressure space ( 51   b ) of the valve body ( 51 ), respectively. 
     
     
         4 . The diaphragm pump of  claim 3 , wherein a first opening and closing means ( 55 ) and a second opening and closing means ( 56 ) include:
 a pair of O-rings ( 55   a ,  56   a ) installed on left and right inner circumferential surfaces of the shaft hole ( 19 ) while having a certain distance; and   grooves ( 55   b ,  56   b ) formed on left and right inner circumferential surfaces of the shaft, respectively,   wherein when the shaft  20  is fully moved to the right or left, the grooves are collinearly placed with the O-rings located at an outer side adjacent to the second air chamber ( 15   b ) or the first air chamber ( 14   b ), and thus, a gap generated therebetween enables the second air chamber ( 15   b ) and the first air chamber ( 14   b ) to open onto the first pressure space ( 51   b ) and the second pressure ( 51   c ) of the valve body ( 51 ), respectively.   
     
     
         5 . The diaphragm pump of  claim 2 , wherein the exhaust port  18  is divided into:
 a first exhaust port ( 18   a ) for discharging the compressed air flowing in the first air chamber ( 14   b ) through the first exhaust space ( 51   d ) to the outside; 
 a second exhaust port ( 18   b ) for discharging the compressed air flowing in the second air chamber ( 15   b ) through the second exhaust space ( 51   e ) to the outside; and 
 a third exhaust port ( 18   c ) for discharging the compressed flowing in the first pressure space ( 51   b ) and the second pressure space ( 51   c ) of the valve body ( 51 ) to the outside. 
 
     
     
         6 . The diaphragm pump of  claim 5 , wherein an outlet side of the first exhaust port ( 18   a ) and an outlet side of the second exhaust port ( 18   b ) are configured to open onto each other, and an outlet side of the third exhaust port ( 18   c ) is configured not to open onto the outlet sides of the first exhaust port ( 18   a ) and the second exhaust port ( 18   b ). 
     
     
         7 . The diaphragm pump of  claim 5 , wherein each of the first exhaust port ( 18   a ) and the second exhaust port ( 18   b ) has an internal diameter which is gradationally or gradually increased toward an outlet. 
     
     
         8 . The diaphragm pump of  claim 6 , wherein each of the first exhaust port ( 18   a ) and the second exhaust port ( 18   b ) has an internal diameter which is gradationally or gradually increased toward an outlet.