A pump assembly. The pump assembly may comprise a motor portion for driving a fluid pumping portion via a piston. The motor portion may comprise: a spool and a spool housing assembly having a spool chamber. The spool may be disposed within the spool chamber. The spool may comprise an upper portion and a lower portion, wherein the diameter of the lower portion is larger than the diameter of the upper portion. The spool may also comprise: (1) two support groove portions for cradling two slide valves and (2) two spool bores, which are in fluid communication with the two slide valves. The piston of the pump assembly may comprise a valve stem having a valve stem bore and valve stem openings. The valve stem openings may be funnel-shaped or may inwardly slope into the valve stem bore to prevent or minimize cutting or shredding of a blown seal.

A pump housing includes an integral vent flow path extending between a low-pressure region and the reservoir. The vent path provides fluid communication between the downstream side of a throat seal dividing the low-pressure region from a high-pressure region and the reservoir. Lubricant flows through the vent path from the reservoir to the low-pressure region to provide lubrication to the throat seal.

A reduced-noise pneumatic motor has a housing with a cap disposed at a first end, the cap having an air inlet; a base disposed at a second end, the base having an air outlet hole formed therein and configured to at least partially receive a noise damping system, and a piston pump extending therethrough; and bolts extending from the cap to the base to secure the cap and the base to the housing. A pneumatic piston is disposed within the housing, and includes a shuttle valve situated within a central bore of the pneumatic piston. A piston rod has a first end extending into the piston pump and a second end secured to a spring which biases the piston rod against the pneumatic piston.

A drive mechanism including a pneumatic cylinder housing, a piston reciprocating in the housing between a first and second dead centers, a pumping shaft driven by the piston, a valve unit, a gas inlet, a gas outlet, the gas inlet is in fluid communication with a first chamber of the cylinder volume, and a second chamber of the cylinder volume in fluid communication with the gas outlet, when the valve unit is in a first state. The gas inlet is in fluid communication with the second chamber of the cylinder volume, and the first chamber of the cylinder volume in fluid communication with the gas outlet, when the valve unit is in a second state. The drive mechanism provides a valve unit actuator having a magnet located adjacent the valve unit and configured to alternately shift the state of the valve unit between the first state and the second state.

A drive mechanism including a pneumatic cylinder housing, a piston reciprocating in the housing between a first and second dead centers, a pumping shaft driven by the piston, a valve unit, a gas inlet, a gas outlet, the gas inlet is in fluid communication with a first chamber of the cylinder volume, and a second chamber of the cylinder volume in fluid communication with the gas outlet, when the valve unit is in a first state. The gas inlet is in fluid communication with the second chamber of the cylinder volume, and the first chamber of the cylinder volume in fluid communication with the gas outlet, when the valve unit is in a second state. The drive mechanism provides a valve unit actuator having a magnet located adjacent the valve unit and configured to alternately shift the state of the valve unit between the first state and the second state.

A drum unloader may include a pump assembly, a motor, a plate, a piston-cylinder assembly, and a sensor. The motor drives the pump assembly. The plate is mounted to the pump assembly and includes an inlet to the pump assembly. The piston-cylinder assembly includes a housing, a piston, and a piston rod. The housing defines a bore. The piston is received within the bore and cooperates with the housing to define a first cavity and a second cavity. The piston rod is attached to and extends from the piston such that the piston rod extends through the first cavity. The piston rod is coupled to the pump assembly, the motor and the plate such that movement of the piston within the bore causes corresponding movement of the pump assembly, the motor and the plate relative to the housing. The sensor measures a pressure within the second cavity.

A thermal operated fluid pump has a plunger which is moved by a thermally expandable element to compress a fluid, such as natural gas, into a storage cylinder.

A thermal operated fluid pump has a plunger which is moved by a thermally expandable element to compress a fluid, such as natural gas, into a storage cylinder.

A zero emission reciprocating drive pump. The reciprocating drive pump may comprise: a spool and housing assembly. The housing assembly may comprise a flange, spool housing, first chamber, second chamber, and first seal. The flange may attached to a proximal end of the spool housing. The first chamber may be within the flange. The second chamber may be within the spool housing. The spool may be substantially disposed in and reciprocally movable in the second chamber. A proximal end portion of the spool may move reciprocally into and out of the first chamber. The first seal may be positioned substantially adjacent to the first chamber and the second chamber and may contact the proximal end portion of the spool. The flange may comprise a lip that extends substantially along a width of a distal end of the first seal, such that the first seal does not pop out of place.

A zero emission reciprocating drive pump. The reciprocating drive pump may comprise: a spool and housing assembly. The housing assembly may comprise a flange, spool housing, first chamber, second chamber, and first seal. The flange may attached to a proximal end of the spool housing. The first chamber may be within the flange. The second chamber may be within the spool housing. The spool may be substantially disposed in and reciprocally movable in the second chamber. A proximal end portion of the spool may move reciprocally into and out of the first chamber. The first seal may be positioned substantially adjacent to the first chamber and the second chamber and may contact the proximal end portion of the spool. The flange may comprise a lip that extends substantially along a width of a distal end of the first seal, such that the first seal does not pop out of place.