Patent ID: 8602750

Claim:
A liquid supply device, which expands and contracts a drive pump chamber by a drive rod, causes a liquid to flow in the drive pump chamber, and discharges the inflow liquid toward an outside from the drive pump chamber, the device comprising: a housing for the drive pump chamber, in which the drive rod is reciprocably mounted forward and backward directions along an axial direction; a pump member provided between the drive rod and the housing, the pump member having an end portion fixed to the drive rod, a communication chamber being formed between an inner circumferential face of the housing and the pump member, and the pump member elastically deforming axially according to a movement of the drive rod; an orifice member attached to the end portion of the pump member so as not to be moved with respect to the drive rod, the orifice member partitioning an interior of the housing into the drive pump chamber and the communication chamber, a communication gap communicating with the drive pump chamber and the communication chamber being formed between an outer circumferential face of the orifice member and the housing; and a valve member disposed in the drive pump chamber, the valve member being movable with respect to the orifice member, the valve member blocking one or more through hole formed in the orifice member when the drive rod is moved forward, and opening the through hole when the drive rod is moved backward, wherein in a state of moving forward the drive rod to close the through hole, the drive pump chamber is driven for pressurization, and in a state of moving backward the drive rod, the liquid in the communication chamber is guided into the drive pump chamber via the though hole.