An inlet valve system (10), as may be used for a cylinder chamber (20) of a compressor, such as a reciprocating compressor, is disclosed. A plurality of inlet valves (250) is movable between an open position and a closed position. The plurality of inlet valves is arranged between an unloader chamber (120) and a cylinder chamber (20) of the compressor. A control valve (270, 270′) is coupled to a controller (300) and is movable between a first position and a second position to close the inlet valves. A check valve (260, 260′) is movable between a first position and a second position to open the inlet valves. The check valve and the control valve are respectively fluidly coupled to a control chamber (252), which is decoupled from any pressure control external to cylinder chamber (20).

A high-pressure pump has a metering valve and a valve stopper. The stopper has a regulation portion which an end surface of the valve is brought into contact with. An outer diameter of the regulation portion is equal to an outer diameter of the outer peripheral surface of the valve. A cylindrical sleeve is disposed around the regulation portion. When the end surface of the valve is in contact with the regulation portion, the sleeve covers a tapered surface of the valve.

A low-force, non-displacement, micro/miniature valve and/or pump assembly is provided. A tube component having a first side port coupled to an inlet portion and a second side port coupled to an outlet portion can be selectively moved to alternatively couple the side ports to a first or second piston pump chamber. First and second pistons can be actuated after positioning the tube component to either draw in fluid or push out fluid from either the first or second piston pump chambers during each actuation of the pistons. The fluid can be drawn in from a reservoir and can be expelled to a patient for providing a dose of the fluid to the patient.

A dual active valve positive displacement pump comprising: A housing holding the pump's components. A piston with an internal cavity divided into two fluidly-isolated volumes by a freely-moving diaphragm, one of the two volumes being fluidly connected with a volume between piston and housing which contains driver pressure from a pressure source. The piston is reciprocally movable inside the housing under positive or negative driver pressure. An active inlet valve operable by driver pressure actuates when the driver pressure is more than the maximum pressure at the pump inlet port. An active outlet valve operable by driver pressure actuates when the driver pressure is less than the minimum pressure at the pump outlet port. The diaphragm separates pumped fluid from operational fluid used to move the diaphragm inside the piston cavity and transmits pressure at the inlet port when the inlet valve is open, and at the outlet port when the outlet valve is open.

A low-force, non-displacement, micro/miniature valve and/or pump assembly is provided. A tube component having a first side port coupled to an inlet portion and a second side port coupled to an outlet portion can be selectively moved to alternatively couple the side ports to a first or second piston pump chamber. First and second pistons can be actuated after positioning the tube component to either draw in fluid or push out fluid from either the first or second piston pump chambers during each actuation of the pistons. The fluid can be drawn in from a reservoir and can be expelled to a patient for providing a dose of the fluid to the patient.

There is described a patch pump comprising a cartridge, a power source, a pump system, a drug delivery device and a control system configured to operate in particular the pump system and the drug delivery device. The pump system comprises, on the one hand, a pump having a pump housing containing a pump piston and a valve piston and, on the other hand, a pump drive comprising a piston motor and a valve motor for driving the pump piston and the valve piston independently from each other through a first and a second transmission. The drug delivery device comprises a transdermal delivery system having a needle actuation mechanism configured for transdermal insertion of a cannula.

Pump systems with pinch valves for surgical procedures. At least some of the example embodiments are pump systems including a stationary housing defining a front face. A tube support extends outwardly from the front face for aligning and supporting a first tube and a second tube. At least one pinch member is movable relative to the tube support by a power actuator operably coupled to the at least one pinch member and configured to have three orientations that define: a first arrangement of the pinch member relative to the tube support configured to pinch closed the first tube, a second arrangement of the at least one pinch member relative to the tube support configured to pinch closed the second tube, and a third arrangement of the at least one pinch member relative to the tube support configured to pinch closed neither the first tube nor the second tube.

A low-force, non-displacement, micro/miniature valve and/or pump assembly is provided. A tube component having a first side port coupled to an inlet portion and a second side port coupled to an outlet portion can be selectively moved to alternatively couple the side ports to a first or second piston pump chamber. First and second pistons can be actuated after positioning the tube component to either draw in fluid or push out fluid from either the first or second piston pump chambers during each actuation of the pistons. The fluid can be drawn in from a reservoir and can be expelled to a patient for providing a dose of the fluid to the patient.

A plunger pump includes a cylinder having a cylinder chamber, and a first through hole and a second through hole that open from an inner circumferential surface toward an outer circumferential surface of the cylinder chamber, and a plunger inserted in the cylinder chamber and configured to make a reciprocating motion with respect to the cylinder chamber. An inner circumferential portion of the cylinder has an inner circumferential surface, and a helical first groove portion on the inner circumferential surface, the helical first groove portion being configured to communicate with at least one of the first through hole and the second through hole.

Pump systems with pinch valves for surgical procedures. At least some of the example embodiments are pump systems including a stationary housing defining a front face. A tube support extends outwardly from the front face for aligning and supporting a first tube and a second tube. At least one pinch member is movable relative to the tube support by a power actuator operably coupled to the at least one pinch member and configured to have three orientations that define: a first arrangement of the pinch member relative to the tube support configured to pinch closed the first tube, a second arrangement of the at least one pinch member relative to the tube support configured to pinch closed the second tube, and a third arrangement of the at least one pinch member relative to the tube support configured to pinch closed neither the first tube nor the second tube.