A rotary pump for a fluid metering system is provided. The rotary pump reciprocates, and is reversed by a signal from a limit switch that is deflected by an actuator arm on a rotating sleeve of the pump system. The rotary pump includes a plunger and optional stopper formed from a two-shot molding process, and including seals overmolded onto the head of the plunger and the head of the optional stopper.

A system for precision liquid delivery includes a gas reservoir having a known volume. The system has a tightly load-coupled pneumatic driver (a “TLCP driver”) that is configured to receive input power to cause the TLCP driver to move gas into the gas reservoir to produce a gas drive pressure. A valve is configured to couple the gas reservoir with a fluid reservoir having an unknown volume. The valve is further configured to selectively isolate or pneumatically couple pressures in the gas reservoir and the fluid reservoir. A gas-fluid interface couples pressure in the fluid reservoir to pressure in a fluid path. The fluid path is configured so that the fluid drive pressure driving the liquid in the fluid path is substantially the same as the fluid reservoir pressure. The system also has a pressure sensor configured to detect pressure in the gas reservoir and/or the fluid reservoir.

A fluid delivery apparatus includes controller hardware, a diaphragm pump, a positive displacement pump, and a fluid conduit extending between the diaphragm pump and the positive displacement pump. During operation, and delivering fluid to a downstream recipient, the controller hardware draws fluid into a chamber of the diaphragm pump from a fluid source container. The controller hardware applies pressure to the chamber of the diaphragm pump to output the fluid in the chamber of the diaphragm pump downstream through the fluid conduit to the positive displacement pump. During application of the pressure to the chamber and outputting the fluid in the chamber of the diaphragm pump downstream, the controller hardware activates the positive displacement pump to pump the fluid from the positive displacement pump to the downstream recipient.

An infusion pump is disclosed. The infusion pump comprises a chamber having a distal end and a proximal end, and a longitudinal axis between the proximal end and the distal end. A piston is arranged for reciprocating movement within the chamber and along the longitudinal axis. At least one outlet is arranged from the chamber and may comprise an outlet valve. At least one inlet is provided into the chamber. The outlet and the inlet are axially spaced apart along the longitudinal axis of the chamber. A method for operating the pump is also provided.

A monitoring method and dosing pump system monitor operation of a dosing pump including a dosing chamber (2), a displacement element (4) and an electric drive (12). A position (S) of the displacement element and a pressure (P) inside the dosing chamber are continuously recorded as a curve in a pressure-stroke diagram. The method includes monitoring at least one characteristic portion (36, 38, 40, 42, B, C) of the curve in the pressure-stroke diagram by detecting a possible shift (A) of the characteristic portion over several strokes. The method further includes one or both of: adjusting a control of the electric drive based on the detected shift; and determining a trend of the shift over several strokes of the displacement element and determining based on the trend whether and/or when the shift will reach a predefined limit. A dosing pump system with the dosing pump execute the method.

Automatic electric actuation of the pumping mechanism of a liquid dispenser apparatus is provided by configuring a hollow tube to cooperate with an electromagnetically driven actuator and further configuring the hollow tube to inter-fit with a stem of a liquid dispensing pump. Actuation of the actuator may, for example, drive the pump stem downwardly to cause a pumping action. Suitable actuators include, for example, solenoids, voice coil actuators and stepping motors.

Automatic electric actuation of the pumping mechanism of a liquid dispenser apparatus is provided by configuring a hollow tube to cooperate with an electromagnetically driven actuator and further configuring the hollow tube to inter-fit with a stem of a liquid dispensing pump. Actuation of the actuator may, for example, drive the pump stem downwardly to cause a pumping action. Suitable actuators include, for example, solenoids, voice coil actuators and stepping motors.

A metering pump system includes a variable displacement pump having an inlet and an outlet, a flow sensing valve fluidically connected to the outlet of the variable displacement pump, and an actuator mechanically coupled to a displacement mechanism of the variable displacement pump. The metering pump system also includes an electronic engine controller in communication with the flow sensing valve. An electrohydraulic servo valve is electrically connected to the electronic engine controller and hydraulically connected to the actuator. The electrohydraulic servo valve is configured to hydraulically drive the actuator to move the displacement mechanism to change displacement of the variable displacement pump.

A metering pump system includes a variable displacement pump having an inlet and an outlet, a flow sensing valve fluidically connected to the outlet of the variable displacement pump, and an actuator mechanically coupled to a displacement mechanism of the variable displacement pump. The metering pump system also includes an electronic engine controller in communication with the flow sensing valve. An electrohydraulic servo valve is electrically connected to the electronic engine controller and hydraulically connected to the actuator. The electrohydraulic servo valve is configured to hydraulically drive the actuator to move the displacement mechanism to change displacement of the variable displacement pump.

A multiflow pump for fluids, having an electromagnetic translator drive, a displacement piston unit, a pump head, and at least one outlet valve device. The displacement piston contains a bearing journal with a spring receptacle, a carrier plate, and a plurality of pump pistons, wherein the displacement piston unit is configured in one piece.