Patent ID: 8186972

Claim:
A multi-stage expansible chamber pump system, comprising: first and second pump units ( 30 , 40 ) each including a low pressure air chamber ( 31 , 41 ), a fluid chamber, and a pump piston separating said low pressure air and fluid chambers; a high pressure pump unit ( 60 ) including left and right side high pressure air chambers ( 62 , 61 ) and a high pressure pump piston separating said left and right side high pressure air chambers; said pump piston ( 33 ) of the first pump unit, said pump piston ( 43 ) of the second pump unit and said high pressure pump piston ( 63 ) disposed on a common piston rod ( 35 ) for reciprocating movement in unison with said common piston rod; a direction control valve disposed to receive high pressure air divided into a Control air component and a Process air component; said Control air component effective to dispose said direction control valve alternately in a first valve condition and a second valve condition to direct said Process air component alternately in a sequence wherein the Process air component is directed: a. to said left side high pressure air chamber ( 62 ), and from said right side high pressure air chamber ( 61 ) to said low pressure air chamber ( 41 ) of the second pump unit, and from said low pressure air chamber ( 31 ) of the first pump unit to atmosphere; and b. to said right side high pressure air chamber ( 61 ), and from said left side high pressure air chamber ( 62 ) to said low pressure air chamber ( 31 ) of the first pump unit, and from said low pressure air chamber ( 41 ) of second pump unit to atmosphere, and c. again to said left side high pressure air chamber, to continue the sequence; whereby said pump piston ( 33 ) of the first pump unit, said pump piston ( 43 ) of the second pump unit, and said high pressure pump piston ( 63 ) reciprocate in unison to pump fluid through said fluid chamber ( 32 ) of the first pump unit and said fluid chamber ( 42 ) of the second pump unit.