Foam Pump

Abstract

A foam pump, comprising a pump body ( 1 ), a big cover ( 2 ), a big piston ( 3 ), a small piston ( 4 ), a piston rod ( 5 ), a head cap ( 6 ) and a foam screen ( 7 ), featured by that: said pump body ( 1 ) is at the upper part, said big cover ( 2 ) is at the lower part, said pump body ( 1 ) being integrated with said big cover ( 2 ), said head cap ( 6 ) being integrated with the lower big piston ( 3 ); a sealing ring ( 9 ) of elastic materials being provided between said big piston ( 3 ) and the inner wall of said pump body ( 1 ) for tight engagement, which forms an one-way valve structure, which makes the pump body and the big cover integrated, thus the air cavity can be enlarged, the working pressure of the foam pump can be improved with the big cover of the same size, and the foaming effect of the foam pump can be enhanced; said head cap being integrated with said big piston, a sealing ring is provided between said big piston and the inside wall of the pump body, which simplifies the structure of the big piston and makes the internal structure of the foam pump more compact.

1 . A foam pump comprising:
 a pump body ( 1 ), a big cover ( 2 ), a big piston ( 3 ), a small piston ( 4 ), a piston rod ( 5 ), a head cap ( 6 ) and foam screen ( 7 );   an one-way valve being provided in said piston rod ( 5 ), which is connected with an air cavity ( 11 ) of pump body;   said one-way valve adopting sleeve-shaped valve leaves ( 8 ) which are made of elastic materials and are provided with staged surfaces to be installed inside said piston rod ( 5 );   said valve leaves ( 8 ) further adopting sealing valve with ascending diameter becoming bigger gradually and tapered cavity on the upper part for tight engagement with a connecting hole ( 51 ) on said piston rod ( 5 ), which connects an air-liquid mixing cavity ( 52 ) in said piston rod and the air cavity ( 11 );   said piston rod ( 5 ) being connected with said head cap ( 6 ) from the inside;   said pump body ( 1 ) being at the upper part, said big cover ( 2 ) being at the lower part, said pump body ( 1 ) being integrated with said big cover ( 2 ), said head cap ( 6 ) being integrated with the lower big piston ( 3 );   a sealing ring ( 9 ) of elastic materials being provided between said big piston ( 3 ) and the inner wall of said pump body ( 1 ) for tight engagement, which forms an one-way valve structure.   
   
   
       2 . The foam pump according to  claim 1 , wherein said big cover ( 2 ) is provided with an air hole ( 21 ) for connection with the outside, said air hole ( 21 ) being connected with the outside via an one-way valve ( 10 ) inside said big cover ( 2 ). 
   
   
       3 . The foam pump according to  claim 2 , wherein said one-way valve ( 10 ) comprises of an elastic valve and an air hole ( 21 ) in tight engagement. 
   
   
       4 . The foam pump according to  claim 1 , wherein said one-way valve structure is to form a circular groove ( 31 ) along the circumference of said big piston ( 3 ), allowing said sealing ring ( 9 ) to slide up and down inside said groove ( 31 ), which is provided with an air inlets ( 32 ) for connection with the outside on the inner lower wall and the bottom. 
   
   
       5 . The foam pump according to  claim 1 , wherein a circular groove ( 12 ) is formed on the lower part of said pump body ( 1 ), said piston rod ( 5 ) is provided with a shoulder ( 53 ), a spring ( 13 ) is on said piston rod ( 5 ), and is supported between said circular groove ( 12 ) and said shoulder ( 53 ). 
   
   
       6 . The foam pump according to  claim 1 , wherein said pump body ( 1 ) is received in a shield ( 14 ), the big piston ( 3 ) on said head cap is located inside a cam ring ( 141 ) of the shield, the cam ring sets the upper limit for said big piston ( 3 ), said shield ( 14 ) and said head cap ( 6 ) being engaged movably.