Patent ID: 7703743

Claim:
A valve drive device comprising: a motor; a rotational member which is rotated by the motor; a linearly moving member which is engaged with the rotational member; a converting mechanism structured to convert rotation of the rotational member into linear movement to linearly move the linearly moving member; a diaphragm valve which is formed of an elastic body for opening or closing an opening part based on the linear movement of the linearly moving member; and an urging member structured to close the opening part through the diaphragm valve which is abutting with the opening part in an urging state; wherein the converting mechanism is structured to convert rotation of the rotational member into linear movement of the linearly moving member by engaging the rotational member and the linearly moving member with each other; and the urging member is structured to close the opening part with the diaphragm valve in a state that the rotational member and the linearly moving member are in a non-engagement state.