The invention relates to a diaphragm pump comprising a diaphragm assembly and a diaphragm retrieval device comprising a tensile bar, said diaphragm assembly comprising a diaphragm and a diaphragm retaining device which secures said diaphragm, wherein the diaphragm assembly and the tensile bar are force-fittingly interconnected by means of a magnetic force of adhesion.

A pump includes a suction space, a delivery space and valves. The suction space is at least partly bounded by a flexible body and located between end elements, at least one of which can be driven so as to move in a reciprocating manner. The delivery space surrounds the suction space and around which a housing is provided. The valves are provided in the housing and in at least one of the end elements, and are constructed such that when a volume of the suction space is increased, a medium is sucked into said suction space, and when the volume is reduced, the medium flows through one of the valves to the delivery space, from which it is expelled when the volume of the delivery space is reduced.

A rolling diaphragm pump that can inhibit an increase in cost with a simple configuration is provided. A rolling diaphragm pump 1 includes: a housing 2; a piston 3 disposed so as to be slidable relative to an inner peripheral surface of the housing 2 and reciprocatable in an axial direction; a rolling diaphragm 4 having a movable portion 41 disposed at one end portion in the axial direction of the piston 3 and reciprocatable together with the piston 3, a fixed portion 42 fixed to the housing 2, and a flexible connecting portion 43 connecting the movable portion 41 and the fixed portion 42 to each other; a pump chamber 5 defined by the rolling diaphragm 4 at one side in the axial direction within the housing 2 and into and from which a transport fluid is sucked and discharged by changing a volume of an interior of the pump chamber 5 by deformation of the connecting portion 43 due to reciprocation of the piston 3; and a working fluid chamber 6 defined by another end portion in the axial direction of the piston 3 at another side in the axial direction within the housing 2 and into and from which a working fluid is supplied and discharged, thereby causing the piston 3 to reciprocate.

A multi-chamber wobble plate pump that includes a housing with an inlet port, an outlet port and a plurality of pump chambers. The pump includes inlet valves having an asymmetric cross-section with a thin section and/or a peripheral seal bead. A wobble plate is coupled to a diaphragm and a plurality of pistons. Rotation of the wobble plate moves the pistons within the pump chambers to draw in and force fluid out of the chambers. The diaphragm may have a thin cross-sectional area that creates a hinge. The pump may further have a pulsation damper and a flexible liner located in-line with an outward flow of fluid and which absorb pressure transients and reduce noise. The pulsation dampener may be integrated into the relief valve. An elastomeric sleeve may be located adjacent to the wobble plate to provide both a seal and a noise absorber.

A reciprocating fluid pump includes a pump body, a subject fluid chamber, a first plunger located within the subject fluid chamber of the pump body and having a first head portion and a first bellows, the first plunger configured to expand and compress in a reciprocating action to pump the subject fluid through the subject fluid chamber within the pump body, wherein the first head portion and the first bellows have a first cross-sectional dimension, and a second plunger located within the subject fluid chamber of the pump body and having a second head portion and a second bellows, the second plunger configured to expand and compress in a reciprocating action to pump the subject fluid through the subject fluid chamber within the pump body, wherein the second head portion and the second bellows have a second cross-sectional dimension that is smaller than the first cross-sectional dimension.

This invention is an eccentric pushrod cover device for high-volume double diaphragm pumps which provides protection of the operator from the pushrod during the operation of the pump. The eccentric pushrod cover device is comprised of a mounting plate, top plate, and face plate that are modularly assembled. The modular construction of the eccentric pushrod cover device allows for the device to be retrofitted onto existing pumps and allows for quick access to the pushrod for intermittent maintenance. It is anticipated that the elliptical slotted cutouts could vary in size and orientation.

A diaphragm (18) includes a disk-shaped center planar portion (40) and a first lip (42) and a second lip (44) on the outermost edge of the disk shaped portion (40) and extending transversely to the planar disk portion (40). The first lip (42) is on a first side of the diaphragm (18) and the second lip (44) is on an opposite side of the diaphragm (18). A mounting portion (38) extends outward from the center of the face of the planar portion (40) on the first side of the diaphragm (18). For metering pump applications pumping harsh fluids, the diaphragm (18) is typically made from a fluoropolymer and in particular may be made from polytetrafluoroethylene (PTFE).

Described is a method for treating water with sodium hydroxide. The method can increase the accuracy of the volume of a stock sodium hydroxide solution that is delivered to the water being treated. The method can include pumping a concentrated aqueous sodium hydroxide stock solution with a diaphragm pumping system that has a two-part diaphragm assembly with a polymeric diaphragm overmolded onto a rigid insert. The polymeric diaphragm can be made of a fully-vulcanized ethylene propylene diene monomer rubber that is injection molded over the rigid insert.

A system, method apparatus including a bimetallic mechanical pump diaphragm for fluid handling including two walls forming a chamber divided by a snap-acting bimetallic mechanical diaphragm which uses the rapid, concavity inversing, buckling transition of the diaphragm pump fluid as thermal energy in a first fluid is converted to mechanical energy to push a second fluid as the diaphragm moves from a first position to a second position in the chamber. Two sets of inlet and outlet passageways include one way valves to control the flow of the first and second fluids having different temperatures.

The invention provides an actuator having a wedge shaped member arranged to move in substantially linear reciprocating motion. A drive member is operatively coupled to the wedge shaped member. The wedge shaped member is arranged to deflect the drive member as the wedge shaped member moves. A shape memory material has a first end electrically connected to a first electrical connection terminal and fixed with respect to the first electrical connection terminal, and a second end electrically connected to the wedge shaped member and fixed with respect to the wedge shaped member. The wedge shaped member is electrically connected to a second electrical connection terminal. The actuator may be used in a pump having a pumping chamber with a membrane the displacement of which changes the pumping chamber volume. The drive member of the actuator is operatively coupled to the pumping chamber membrane. The pump may be used in an infusion system for the infusion of a liquid therapeutic product.