US 4,370,103 AGranted

Piston pump with discharge valve, inlet valve and misalignment compensating means in a pump head

AssigneeArrowhead Research Corporation

InventorDwight E. Tripp

Life of this patent

Estimating the term…

Loading patent…

Abstract

A piston pump mechanism for use in positive pressure and vacuum pumping systems for pumping various gases such as air, freon, natural gas, etc. The pump mechanism incorporates an inlet and discharge valve system that substantially eliminates any unpurged or unswept volume of gas within a pump cylinder during each reciprocating stroke of the pump piston. The pump mechanism also incorporates a control spool that floats within a pump head and has a sealed flexible interconnection with the discharge valve that allows the discharge valve to seek optimum seating engagement about the entire periphery of the cylinder. The valve control spool may be pressure balanced or controllably unbalanced, as desired, for influence of the discharge valve. The spool also provides for inlet of gas to an inlet valve that may be incorporated into the discharge valve.

Claims29

Dependent claims

A piston pump mechanism for positive gas pressure and vacuum pumping operations, said piston pump mechanism comprising:

pump body means defining cylinder means therein, said pump body means defining seat means circumscribing said cylinder means and further defining discharge chamber means surrounding said seat means;
a pump head being affixed to said pump body means and cooperating therewith to define a discharge chamber surrounding said seat means and defining an inlet chamber;
piston means being movably disposed within said cylinder means;
means for imparting reciprocating movement to said piston means within said cylinder means;
discharge valve means defining sealing surface means, said sealing surface means adapted to establish sealing engagement with said seat means said discharge valve means being movable to the open position thereof by gas pressure within said cylinder to allow discharge of gas from cylinder means into said discharge chamber means and being moved to the closed position thereof by at least one of gas pressure within said discharge chamber means and mechanical urging means;
inlet valve means being defined in said discharge valve means and communicating with said cylinder means and with said inlet chamber, said inlet valve means adapted to open responsive to negative pressure within said cylinder means to allow inlet of gas into said cylinder and adapted to close responsive to positive gas pressure within said cylinder means to allow compression of gas within said cylinder;
valve control spool means being movably positioned within said pump head;
and
location control means being interposed between said spool means and discharge valve means, said location control means providing lateral and pivotal control for said discharge valve and defining omnidirectional pivot means allowing pivoting of said discharge valve to accommodate seat and head misalignment.

6 more elements

A pump head mechanism for piston pumps adapted for positive gas pressure and vacuum pumping operations and incorporating a pump body defining piston containing cylinder means and seat means about said cylinder means, said pump head mechanism comprising:

a head structure adapted to be secured in fixed relation to a pump body, said head structure defining an inlet chamber and a discharge chamber, said head structure being further formed to define a spool cavity intersecting said inlet and discharge chambers and to define pressure balancing passage means in communication with said discharge chamber;
a discharge valve being received within said discharge chamber and defining a circular sealing surface adapted to establish sealing engagement with a seat surface defined about the cylinder of a pump body, said discharge valve defining first sealing surface means;
a spool element being movably received within said spool cavity, said spool element defining inlet passage means, said spool element cooperating with said head structure within said cavity to define a pressure balancing chamber, said pressure balancing chamber being in communication with said pressure balancing passage means, said spool element defining second sealing surface means;
first seal means sealing said spool element with respect to said head structure and sealing communication between said inlet and discharge chambers;
in inlet valve being provided in said discharge valve;
means sealing said discharge valve with respect to said spool and sealing said inlet passage means with respect to said discharge chamber;
a compression spring being disposed within said cavity and urging said spool toward said discharge valve, whereby said discharge valve is seated responsive to the spring force thereof when balanced pressure conditions exist across said discharge valve;
and
second seal means establishing sealing engagement with said first and second sealing surface means and permitting angular movement of said discharge valve relative to said spool element to permit said discharge valve to seek optimum sealing engagement with said seat surface.

6 more elements

Dependencies are inferred from the claim text.