A pumping cassette including a housing having at least two inlet fluid lines and at least two outlet fluid lines. At least one balancing pod within the housing and in fluid connection with the fluid paths. The balancing pod balances the flow of a first fluid and the flow of a second fluid such that the volume of the first fluid equals the volume of the second fluid. The balancing pod also includes a membrane that forms two balancing chambers. Also included in the cassette is at least two reciprocating pressure displacement membrane pumps. The pumps are within the housing and they pump the fluid from a fluid inlet to a fluid outlet line and pump the second fluid from a fluid inlet to a fluid outlet.

Illustrative embodiments of diaphragm pumps including a sensor mount are disclosed. In one illustrative embodiment, a diaphragm pump may include a shaft disposed within a pump housing and coupled to at least one diaphragm, a mount removably attached to the pump housing and having a sensor receptacle, and a proximity sensor received in the sensor receptacle of the mount such that a sensing end of the proximity sensor is flush with an end of the sensor receptacle nearest the shaft.

A drive system for a pump includes a housing defining an internal pressure chamber, a working fluid disposed within and charging the internal pressure chamber, and a reciprocating member disposed within the internal pressure chamber. A fluid displacement component has first and second surfaces. The first surface is configured to contact the working fluid and the second surface is configured to contact the process fluid. The area of the first surface is greater than the area of the second surface. A pull extends between and connects the reciprocating member and the fluid displacement component. The pull mechanically transfers a pulling force from the reciprocating member to the fluid displacement component.

A ball non-return valve that can be integrated with a diaphragm pump or the like, does not transmit strain generated by stress during valve assembly to a ball seal portion, and can stably maintain sealing performance, and a diaphragm pump are disclosed. The non-return valve includes a valve seat having a through-hole, and a ball that opens and closes a flow of a fluid through the through-hole. The valve seat made of a corrosion resistant material is composed of a first valve seat that can support the ball and seal the through-hole, and a second valve seat that has a substantially cylindrical shape surrounding the first valve seat and in which the space between a valve case and the second valve seat is sealed by an O-ring. Clearances d3 and d4 are formed between the first valve seat and the second valve seat, and a horizontal surface of a notched portion of the second valve seat is mounted on an upper surface of a flange portion of the first valve seat.

The invention relates to a recirculation device for a gas of a process device, said recirculation device comprising a recirculation pump, wherein the recirculation pump is a side channel pump.

To manufacture a diaphragm pump with higher reliability in which the mechanism of a main valve is simplified without a pilot chamber. A diaphragm pump 10 includes paired diaphragms 34 and 44 that define pump chambers 36, 46 and air chambers 32, 42, a main body unit 20 that slidably supports a center rod 120 at a central portion of each diaphragm 34, 44 so as to be capable of reciprocating the center rod 120, and a valve body 80 that houses a spool 100 that switches supply of a fluid to the air chambers 32 and 42 so as to reciprocate the center rod 120, the valve body 80 including a sleeve 84, and the spool 100 that is disposed inside the sleeve 84 to be reciprocated in an axial direction, wherein the spool 100 is composed of a disc-shaped portion S3, a disc-shaped portion S2, and a disc-shaped portion S1, and a surface area of each disc-shaped portion that receives a compressed air pressure has a relationship that an upper side of the disc-shaped portion S3>a lower side of the disc-shaped portion S2>an upper side of the disc-shaped portion S1.

A connection apparatus for sealing to a pathway of a mounting structure includes a body; and a port including a threaded portion extending from the body and a non-threaded portion extending from the threaded portion, the non-threaded portion carrying a gasket, the gasket positioned along the non-threaded portion such that the mounting structure to which the connection apparatus is mounted contacts the gasket prior to the threaded portion engaging a mating threaded portion of the mounting structure, the port providing fluid communication between the body and the pathway of the mounting structure. The body may be that of a valve that supplies any of air, water or oil as an operating fluid to, for example, inlet and outlet valves and a pump chamber of a medical fluid pump of a medical fluid delivery machine.

Embodiments of the present invention relate generally to certain types of reciprocating positive-displacement pumps (which may be referred to hereinafter as pods, pump pods, or pod pumps) used to pump fluids, such as a biological fluid (e.g., blood or peritoneal fluid), a therapeutic fluid (e.g., a medication solution), or a surfactant fluid. The pumps may be configured specifically to impart low shear forces and low turbulence on the fluid as the fluid is pumped from an inlet to an outlet. Such pumps may be particularly useful in pumping fluids that may be damaged by such shear forces (e.g., blood, and particularly heated blood, which is prone to hemolysis) or turbulence (e.g., surfectants or other fluids that may foam or otherwise be damaged or become unstable in the presence of turbulence).

Illustrative embodiments of positive displacement pumps utilizing pressure compensating calibration, as well as related systems and methods, are disclosed. In one illustrative embodiment, a method of operating a positive displacement pump includes sensing, with a pressure sensor disposed at a fluid outlet of the positive displacement pump, a back pressure at the fluid outlet, transmitting a pressure signal associated with the sensed back pressure from the pressure sensor to a controller of the positive displacement pump, and identifying, on the controller, a volume of fluid pumped by the positive displacement pump using the pressure signal.

A pumping cassette including a housing having at least two inlet fluid lines and at least two outlet fluid lines. At least one balancing pod within the housing and in fluid connection with the fluid paths. The balancing pod balances the flow of a first fluid and the flow of a second fluid such that the volume of the first fluid equals the volume of the second fluid. The balancing pod also includes a membrane that forms two balancing chambers. Also included in the cassette is at least two reciprocating pressure displacement membrane pumps. The pumps are within the housing and they pump the fluid from a fluid inlet to a fluid outlet line and pump the second fluid from a fluid inlet to a fluid outlet.