Abstract: A method of operating a system (16) for pumping a fluid, which system comprises a pump (17) comprising a suction side (18) and a discharge side (19); a motor (20) for driving the pump, which motor is drivingly connected to the pump via a shaft; a recirculation conduit (23) providing a fluid path for the fluid from the discharge side to the suction side of the pump; and a control valve controlling the flow of the fluid through the recirculation conduit, which method comprises the steps of: mapping a plurality of minimum torque diagrams for the pump, where each minimum torque diagram identifies the minimum allowable torque of the pump as a function of an operational parameter of the pump, e.g.

Abstract: A magnetic bearing control apparatus and a vacuum pump which do not require a displacement sensor, which enable control with high accuracy, and which are small and low cost. A rate of change (di/dt) that is a time derivative of a current value Im flowing through an electromagnet varies in accordance with a magnitude of a displacement of a gap between a target member and the electromagnet. The rate of change (di/dt) can be obtained by detecting a voltage value Vs that is generated at both ends of an inductive element. Therefore, by detecting the voltage value Vs, the magnitude of the displacement of the gap can be estimated by calculation. Inductive elements are connected in series to electromagnets and the voltage Vs between the inductive elements is detected by the differential input amplifier. A single period of switching of a PWM switching amplifier is constituted by a current control period of the electromagnet and a displacement detection period for detecting the rate of change (di/dt).

Abstract: A peristaltic pump can include a chassis and a chassis retaining portion forming a cavity. The pump can also include a rotor, a cover, and a linkage. The rotor can be disposed within the cavity such that tubing can be held between the rotor and the chassis and/or the chassis retaining portion. The linkage can couple the cover to the chassis. The linkage can include an arm. When opening the cover, the arm can pivot such that the chassis moves away from the chassis retaining portion to widen the cavity. When closing the cover, the arm can pivot such that the chassis moves toward the chassis retaining portion. When closed, a stop can restrict further movement of a corresponding member toward the chassis retaining portion.

Abstract: A motor for a fan, a ventilator, a pump or a compressor includes integrated motor electronics and at least one sensor unit for pressure or volume flow control. The at least one sensor unit may be a module that can be plugged onto or into the integrated motor electronics or may be at least partly integrated into the motor electronics. The motor may be an electronically commutated motor. The integrated motor electronics may be configured to supply the at least one sensor unit with energy.

Abstract: A micropump system (100) for a compressible fluid (102) includes a plurality of micropumps (110), rigid flow duct elements (120), a control unit (130), and one or two printed circuit boards (140). The micropumps have an intake opening (112) and an outlet opening (114). The rigid flow duct elements are connected to a respective micropump via a respective, elastically sealed port (122) and with the micropumps form a flow path (104) for the fluid. The one or two printed circuit boards are arranged and configured to electrically connect the control unit to the plurality of micropumps. Each micropump is rigidly fastened to the one or two printed circuit boards via a respective fastening device. A pressure build-up of the fluid flowing through the plurality of micropumps during the use, which is cascaded due to the plurality of micropumps, is provided at a system outlet (106) of the micropump system.

Abstract: A radial hydraulic wind turbine pump system incorporates: 1) a concentric, multi-lobed cam that produces multiple strokes per revolution; 2) a piston profile that maximizes the number of large-diameter pistons arranged radially around the centerline axis; 3) a flexible piston base 50 with internal oil flow; 4) hydraulically connected cylinders which counter displacement issues raised in item 2 above; 5) variable stroke capability leading to infinitely variable output and the ability to disengage unneeded cylinders from the cam; 6) integral reservoir and accumulator capacity; 7) compact, external pressure and return manifolds; 8) axially-oriented pressure and return manifolds 60, 70, and 9) a hydraulic reservoir and pressure tank integrated into the body of the pump.

Abstract: Within an ion pump, accelerated ions leave the center portion of an anode tube due to the anode tube symmetry and the generally symmetrical electric fields present. The apparent symmetry within the anode tube may be altered by making the anode tube longitudinally segmented and applying independent voltages to each segment. The voltages on two adjacent segments may be time varying at different rates to achieve a rasterizing process.

Abstract: Embodiments of the invention provide a pump assembly for a hydraulic tool. The pump assembly can include a reciprocating element that is configured to move between a retracted position and an extended position, a cam surface in the reciprocating element that can engage cam followers, a rotating element that can receive rotational input, and a base that can at least partially surrounds the rotating element. Movement of the cam followers along the cam surface can move the reciprocating element from the retracted position to the extended position.

Abstract: A pressure-controlling device (10) includes a pump (21), a connection pipe (30), a first valve (41), and a second valve (42). The pump (21) has an inlet port (211) and an outlet port (212). The connection pipe (30) has a first end in communication with the outlet port (212), and a second end in communication with the inlet port (211) and that has a first space (31) that contains the first end, a second space (32) that contains the second end, and a third space (33) that is located between the first space (31) and the second space (32).

Abstract: A position deviation calculated by a subtractor of a vacuum pump is input to the PIDs of three modes. The first PID is a PID controller for a high-bias mode, the second PID is a PID controller for a high-rigidity mode, and the third PID is a PID controller for a low-rigidity mode. The output signal of the third PID is extracted as a change of an indicator current for each clock of a PWM frequency and then the mean value of a change of an indicator current for several clocks is determined in a calculating unit. At this point, a switching control unit performs an operation on whether the mean value of the averaged change of the indicator current is larger than a preset redetermined value and then according to the result, an ? value is outputted in the range of 0 to 1 from the switching control unit.

Abstract: A fluid working system such as a pump for displacing a working fluid such as hydraulic fluid or a motor using a working fluid is provided. The system may have a positive displacement machine which includes one or more working chamber with displacement means such as a cylinder with a reciprocating piston. There are also two or more fluid ports to allow the working fluid to flow into and out of the working chamber. The working fluid flows from one fluid port means to another either being forced to do so when pumped or moving the piston when functioning as an engine. The fluid working system has associated therewith a non-dead compliance volume of a material such as syntactic foam. This compliance volume acts to smooth any pressure fluctuations within the working fluid system.

Abstract: A dual priming system connected with a centrifugal pump to evacuate gas therefrom includes a positive displacement pump fluidly connectable with the centrifugal pump and a venturi fluidly connectable with the centrifugal pump in parallel with the positive displacement pump. The dual priming system is operational in a first mode, wherein the positive displacement pump is inactive and the venturi is activated, and a second mode, wherein the positive displacement pump is activated and the venturi is activated.

Abstract: A multi-stage rotary vane pump comprising at least two rotor elements. The rotor elements are supported by a rotor shaft. The rotor elements and the rotor shaft are in the form of a single piece.

Abstract: A pneumatic pump silencer including a body defining an inner volume and having at least one wall including an air outlet orifice, and an attenuating pad having a face arranged across from the air outlet orifice, wherein a gap is arranged between the face of the attenuating pad and an outer face of the wall including the air outlet orifice, the thickness of the gap being between 0.5 mm and 5 mm.

Abstract: Clamps can be secured to a slip joint and limit flow through the same by seating on a diffuser axially regardless of wear and damage in the slip joint. An extension from the clamp seats to the inlet mixer. These extensions can be adjusted from outside the clamp to achieve an individual preload or flow limitation through the slip joint. The extension may be an O-ring or other shape. A biasing drive may connect to and move the extension from an outside surface of the clamp. The biasing drive may include a threaded cap in an outer groove that is linked to a plunger via a spring. Clamps are fabricated of materials that maintain their physical properties when exposed to an operating nuclear reactor environment and may be relatively rigid and resilient metals.

Abstract: An air cycle machine is provided. The air cycle machine can be included an environmental control system of an aircraft. The air cycle machine can include a turbine comprising a plurality of inlet gas flow paths, a compressor driven by the turbine from a shaft, and a fan driven by the turbine from the shaft.

Abstract: A pump assembly for use within a high pressure pumping system includes housing, a head and a base. The housing contains at least one centrifugal pump stage. The head and base are attached to the housing with corresponding internal threaded connections. The head and base are further retained to the housing with corresponding external flanged connections. The external flanged connections provide redundant connections that reduce the risk of separation between the housing and the head and base.

Abstract: A vane rotary compressor may include a main bearing and a sub bearing provided with a plurality of back pressure pockets each having a different pressure formed on a surface facing the cylinder, a rotational shaft radially supported by the main bearing and the sub bearing, a roller provided with a back pressure chamber that communicates with the plurality of back pressure pockets and having a plurality of vanes configured to divide a compression space into a plurality of compression chambers. At least one of the main bearing or the sub bearing is provided with an oil supply passage that communicates with a back pressure pocket having a relatively low pressure among the plurality of back pressure pockets. Accordingly, oil may be smoothly supplied to a back pressure pocket having a low pressure.

Abstract: A fluid working system such as a pump for displacing a working fluid such as hydraulic fluid or a motor using a working fluid is provided. The system may have a positive displacement machine which includes one or more working chamber with displacement means such as a cylinder with a reciprocating piston. There are also two or more fluid ports to allow the working fluid to flow into and out of the working chamber. The working fluid flows from one fluid port means to another either being forced to do so when pumped or moving the piston when functioning as an engine. The fluid working system has associated therewith a non-dead compliance volume of a material such as syntactic foam. This compliance volume acts to smooth any pressure fluctuations within the working fluid system.

Abstract: An air compressor system includes a motor operably connected to an air compressor, a separator tank fluidly connected to the air compressor by a supply line, a compressed air line coupled to the separator tank, a service valve connected to the compressed air line and positioned downstream of the separator tank, and a controller in operable communication with the motor, wherein in response to the controller detecting the motor operating at an idle speed, the controller reduces the motor speed to a low idle speed and reduces pressure in the separator tank, the low idle speed being slower than the idle speed.