Patent ID: 6681962
Filing Date: 2004-01-27
Classification: B05B

Abstract:
A liquid dispensing pump adapted to be connected to a container, comprising:a nozzle head having a nozzle from which a liquid stored in the container is dispensed; an inner tube connected to the nozzle, said tube having (i) a closed end on a side opposite to the nozzle, (ii) a first outward projection at the closed end, (iii) a second outward projection apart from the closed end, and (iv) an opening between the first and second outward projections; a cylinder into which the closed end of the tube is inserted; a piston provided inside the cylinder and movable between the first and second outward projections, said piston comprising two annular packing members, each separately contacting an inner wall of the cylinder and being liquid-tightly slidable along an inner wall of the cylinder, wherein (a) when the nozzle head is not pressed downward, the first outward projection liquid-tightly contacts the piston, and (b) when the nozzle head is pressed downward, the first outward projection is detached from the piston to communicate the tube and the cylinder between the first outward projection and the piston through the opening of the tube, whereas the second outward projection pushes the piston downward; a pushing member which constantly pushes the nozzle head upward; and a one-way valve provided at an end of the cylinder opposite to the nozzle head, said valve opening only in a direction to bring a liquid stored in the container into the cylinder; wherein (I) the liquid in the container moves into the cylinder though the valve when the nozzle head moves upward by the pushing member, and (II) the liquid brought in the cylinder moves between the first outward projection and the piston into the tube through the opening of the tube toward the nozzle when the nozzle head is pressed downward.