Double-acting pump

Claim 2

A double-acting pump comprising a pair of tubes of flexible material, means for flow connecting each of said tubes to a source of liquid supply, means for flow connecting each of said tubes to a discharge line, housing means enclosing each of said tubes to form a sealed chamber thereabout independently of the other for holding a supply of pump fluid about each of said tubes, and means for cyclically and alternately displacing a like fixed volume of such fluid to said chambers to cause alternate pulsations of said tubes of flexible material and produce equal volume discharge per pulsation from each tube.

Claim 3

A double-acting pump in accordance with claim 1, characterized by said means for cyclically and alternately displacing a fixed volume of fluid to said chambers, including a pair of pump fluid chambers, one of said pump fluid chambers having flow connection with one of said sealed chambers, the other of said pump fluid chambers having a flow connection with the other of said sealed chambers, a double acting displacement piston having a piston drive rod at one end to reciprocate said piston between said pump fluid chambers, whereby to cyclically and alternately displace a fixed volume of fluid in said fluid chambers, and means for equalizing the fixed volUmes so displaced, said equalizing means including a rod associated with the opposite end of said displacement piston and having a variable exposure to surrounding liquid during reciprocation of said piston, corresponding to the variable exposure of said piston drive rod.

Claim 4

A double-acting pump in accordance with claim 1, characterized by said means for cyclically and alternately displacing a fixed volume of fluid to said chambers, including a pair of pump fluid chambers, one of said pump fluid chambers having a flow connection with one of said sealed chambers, the other of said pump fluid chambers having flow connection with the other of said sealed chambers, and a double acting displacement piston means adapted to reciprocate between said pump fluid chambers and cyclically and alternately displace equal volumes of fluid from said fluid chambers.

Claim 5

A double-acting pump in accordance with claim 4, characterized by said pump fluid chambers being defined by a tubular wall symmetrically disposed with respect to said sealed chambers and sealed at one end to one of said end plates and at its other end to the other of said end plates, and a partition spanning said tubular wall, intermediate the ends thereof to create a pair of pump fluid chambers in end to end relationship, a flow passageway in one of said end plates and flow connecting one of said pump fluid chambers with one of said sealed chambers, and a flow passageway in the other of said end plates and flow connecting the other of said pump fluid chambers with the other of said sealed chambers, and said double-acting displacement piston means including a displacement piston reciprocally mounted in said partition between said pump fluid chambers, a piston drive rod at one end passing through one of said pump fluid chambers for reciprocating said displacement piston to alternately and cyclically alter the effective volume of said pump fluid chambers and a volume equalizer rod extending from the opposite end of said displacement piston for equalizing the discharge per stroke, from each pump fluid chamber.

Claim 6

A double-acting pump in accordance with claim 1, characterized by said means for cyclically and alternately displacing a like fixed volume of fluid to said chambers, including a pair of pump fluid chambers, one of said pump fluid chambers having flow connection with one of said sealed chambers, the other of said pump fluid chambers having a flow connection with the other of said sealed chambers, and a double-acting piston having a piston drive rod at one end whereby to reciprocate said piston between said pump fluid chambers, whereby to cyclically and alternately discharge a fixed volume of fluid from each of said fluid chambers, and means for equalizing the volume of cyclic discharge from one of said fluid chambers with the volume of cyclic discharge from the other.

Claim 7

A double-acting pump in accordance with claim 4 characterized by said displacement piston having a axial bore at said other end, and said volume equalizer rod being slidably receivable at one end thereof in said bore and at its other end anchored to a fixed wall of said pump.

Claim 8

A double-acting pump in accordance with claim 6 characterized by a leakage passageway through said volume equalizer rod from the interior of the bore of said displacement piston.