Pump device for fluid dispenser

Abstract

A pump device for fluid dispensers is provided whose chamber is partitioned into a pressure room and a fluid room. A piston element is engaged inside the pressure room by an actuating rod to push the piston element downward, or by a resilient element beneath the piston element to restore the piston element back to the top. An air valve element at the bottom of the piston element automatically opens or closes the induction of air to the pressure room when the piston element is moved upward or downward. The fluid room is dedicated to the passage of the fluid. A normally closed fluid valve element is provided at the bottom of the fluid room. When the fluid in the container device is pressurized, the fluid pushes open the fluid valve element, flows into the fluid room and then out of the spout of the pump device.

1 . A pump device for use on a container device for dispensing fluid stored in said container device, said pump device comprising an actuating rod, a head element on the top end of said actuating rod, a fastening element, a piston element, a resilient element, a body member, and a fluid valve element, wherein 
 said body member has a hollow chamber configured on top of an enclosure cap with a discharging spout extended from the outer wall of said chamber; said enclosure cap fastens said pump device to the opening of said container device; said chamber is partitioned into a pressure room and a fluid room;    said pressure room is covered by said fastening element through which said actuating rod is extended; said piston element has a central through hole into which the other end of said actuating rod is embedded; said resilient element is housed inside said pressure room beneath said piston element; an air valve element is provided at the bottom of said through hole that is opened and closed automatically and synchronously with the up and down movement of said piston element; said air valve element is opened to allow air to flow into said pressure room via an air duct running from said head element to the bottom of said actuating rod and connecting to said through hole of said piston element; said air valve element is closed when air is driven out from said pressure room into said container device via an outlet hole; and    said fluid valve element is fixedly positioned at the bottom of said body member, covering said fluid room from the bottom; said fluid valve element has a valve body and a valve lid; said valve lid is attached to said valve body which has a through hole in the center surrounded by an indented lid seat; said valve lid is flipped to fit inside said lid seat and seal said through hole of said fluid valve element; a positioning element provided inside said fluid room appropriately presses the folded section of said valve lid so that said valve lid normally closes said through hole of said fluid valve element.    
   
   
       2 . The pump device according to  claim 1 , wherein corresponding screw threads are provided at the bottom of said head element and around the inner wall of said fastening element respectively, so as to join said head element and said fastening element together when said pump device is not in use.  
   
   
       3 . The pump device according to  claim 1 , wherein fluid of said container device is stored in a storage member inside said container device; said body member of said pump device is fixedly joined to the opening of said storage member on the top; the lower portion of said storage member is flexible; and the fluid in said storage member is squeezed out of said storage member as air is pumped into said container device.  
   
   
       4 . The pump device according to  claim 1 , wherein a plurality of washer rings are provided around the body of said piston element.