Patent ID: 8727305

Claim:
A diaphragm valve in which a valve body having a diaphragm is incorporated into a valve housing, and which performs opening and closing operations to switch between a state where a first flow path communicates with a second flow path and a state where the first flow path is blocked from communicating with the second flow path, the diaphragm valve comprising: a hollow valve body which is disposed so as to be capable of performing a reciprocating operation in an axial direction in the valve housing and which is formed with a communication flow path through which the first flow path and the second flow path communicate with each other; a first diaphragm which is provided to one end portion of the hollow valve body, the first diaphragm having a first mounting portion; a second diaphragm which is provided to the other end of the hollow valve body and moved in synchronization with the first diaphragm via the hollow valve body, the second diaphragm having a second mounting portion, wherein the first diaphragm, the second diaphragm and the hollow valve body collectively constitute a diaphragm unit; a case in which the diaphragm unit is accommodated, the case engaging with the first mounting portion of the first diaphragm and the second mounting portion of the second diaphragm so as to keep a distance between the first and second mounting portions constant; and a reciprocating member which is provided to the valve housing and reciprocably movable in the axial direction and coupled with hollow valve body, wherein when the hollow valve body is moved by the reciprocating member in a direction parallel to a moving direction of the reciprocating member, the hollow valve body abuts on a valve seat portion provided to the valve housing to close the communication flow path.