A device for measuring through-flow processes of fluids. The device includes an inlet, an outlet, a flow housing in which a fluid flows, a drivable displacement meter in the flow housing, a bypass line which bypasses the drivable displacement meter, a pressure difference sensor in the bypass line and in the flow housing, an evaluation and control unit which controls the drivable displacement meter based on a pressure difference existing at the pressure difference sensor, and a cooling channel in the flow housing which has a coolant flow therethrough.

A device for measuring flow processes of fluids. The device includes an inlet, an outlet, a drive unit, a positive displacement flow meter which is driven by the drive unit, the positive displacement flow meter including a positive displacement chamber, a supply duct which fluidically connects the positive displacement chamber to the inlet, a discharge duct which fluidically connects the positive displacement chamber to the outlet, a bypass which bypasses the positive displacement flow meter, a differential pressure sensor arranged in the bypass, and an evaluation and control unit which provides a control of the positive displacement flow meter based on a differential pressure applied to the differential pressure sensor. The supply duct and the discharge duct each rise in a fluid flow direction.

A fluid supply system includes: a centrifugal pump; a starting pump that is connected to the centrifugal pump in series, is provided downstream of the centrifugal pump, and has a discharge flow rate less than that of the centrifugal pump; a measuring valve that is provided downstream of the centrifugal pump and the starting pump, measures an amount of fluid discharged from the centrifugal pump or the starting pump, and discharges the fluid to a downstream each time the fluid reaches a predetermined flow amount; a differential pressure valve that is provided downstream of the centrifugal pump and the starting pump, and is driven based on a differential pressure between an upstream pressure and a downstream pressure of the measuring valve; and a flow rate control valve that is provided downstream of the centrifugal pump and upstream of the differential pressure valve and has a valve opening speed that is set slower than that of the differential pressure valve.

Injection apparatus for injecting a liquid formulation into a molten polymer at high pressure includes a reservoir containing liquid formulation at ambient temperature and pressure which is arrange to flood-feed pump body 26 of a first progressing cavity pump (pep) 4. The first pep 4 is driven by motor 6 and is arranged to accurately meter the liquid formulation into a second pep 8 which is downstream of the first pep and is arranged to increase the pressure of the liquid formulation by 200 bar or more. Downstream of pump 8 is a delivery valve 14 arranged to control passage of liquid formulation, via outlet 17, into pressurised molten polymer stream 75 which is present in an extruder 77.

A self-cleaning transfer gear pump for transferring molten metal includes the following features: a transfer conduit extends upward from an outlet of a base, two rotatable gears are formed of refractory material and disposed in the gear chamber and engage each other during rotation. A boss functioning as a bearing extends from the drive gear and is adapted to be received in an opening in the base. A shaft is fastened at a lower end to the drive gear. A filter is fastened to the base so as to cover the inlet and prevents particles and objects in the molten metal from entering the gear chamber. In operational mode, a motor rotates the shaft and the drive gear whereby the drive gear and the second gear engage each other while being rotated so as to positively displace molten metal from the inlet to the outlet and along the transfer conduit to the remote location. In self-cleaning mode, the motor rotates the shaft and the drive gear effectively to draw molten metal from the transfer conduit by positive displacement, through the outlet, and toward the inlet therefore cleaning the filter by removing the particles adhering to the filter. Also included are a system with optional filter and optional self-cleaning mode but including an inlet portion of a die casting machine, and a method for operating the gear pump. A flow sensor may be used to transmit pulses into and from the transfer conduit so as to enable determination of a volume of molten metal being charged. The control of the molten metal volume being charged is not solely controlled by the flow sensor.

An apparatus may include a pressurized source of viscous material for dispensing onto a substrate. The apparatus may include a progressive cavity pump configured to meter and force material from the material source onward through the apparatus. The apparatus may include a valve operatively connected to the progressive cavity pump and configured to turn on and off flow of material from the progressive cavity pump. Moreover, the device may include an output nozzle for directing the viscous material to the substrate when the valve is in an open position.

A meter-type magnetic pump and its light interrupting module achieve flow measurement by providing a main cavity body having a light interrupter at the inner side of a first cavity, and providing at least a light interrupting element in the first cavity and fastened around the rotating shaft, such that the light interrupting element is brought into rotation by the rotating shaft, wherein the at least one light interrupting blade of the at least one light interrupting element periodically interrupts a light source provided by the light interrupter, allowing the light interrupter to generate at least one signal, electrically coupling the control circuit with the light interrupter to receive the at least one signal and perform a measuring process.

A portable mechanical ventilator having a Roots blower provides a desired gas flow and pressure to a patient circuit. The mechanical ventilator includes a flow meter operative to measure gas flow produced by the Roots blower and an exhalation control module configured to operate an exhalation valve connected to the patient circuit. A bias valve connected between the Roots blower and the patient circuit is specifically configured to generate a bias pressure relative to the patient circuit pressure at the exhalation control module. The bias valve attenuates pulsating gas flow produced by the Roots blower such that gas flowing to the mass flow meter exhibits a substantially constant pressure characteristic. The bias pressure facilitates closing of the exhalation valve at the start of inspiration, regulates positive end expiratory pressure during exhalation, and purges sense lines via a pressure transducer module.

A pump for conveying a fluid includes a pump housing with an inlet, an outlet, an inner circumferential surface and a geometric axis. An eccentric is rotatable in the housing around the geometric axis. A deformable element is disposed in a pump gap between inner and outer surfaces of the eccentric. A conveying channel is formed from inlet to outlet by the deformable element and the inner circumferential surface. The deformable element is pressed in sections against the housing by the outer eccentric surface, forming a displaceable seal of the channel and a closed pump volume in the channel being displaceable by rotation of the eccentric for conveying the fluid along the channel from inlet to outlet. The deformable element has a protrusion on one or both sides towards the geometric axis extending over the outer eccentric surface and contacting the deformable element. A centering ring is inside the protrusion.

The disclosure herein relates to device, for example a gear pump, for pumping fluid. The gear pump comprise a motor for driving a rotatable drive shaft; a drive gear configured to be driven by the drive shaft; an idler gear which meshes with the drive gear; an annular magnet disposed coaxially with the drive shaft and configured to rotate therewith; and a sensor for sensing rotation of the annular magnet and generating an output signal corresponding to a rotational position of the drive shaft.