The present invention concerns a method of controlling a liquid volume which can be conveyed with a metering pump in a given time, comprising the steps: a. providing an input signal for controlling the liquid volume which can be conveyed with the metering pump in the given time, and b.lLinking the input signal to an actuating signal which influences the liquid volume which can be conveyed with the metering pump in the given time so that a change in the input signal leads to a change in the actuating signal and thus a change in the liquid volume which can be conveyed. To react to individual process demands it is proposed according to the invention that linking in step b. is effected in such a way that a change in the input signal leads to a change in the liquid volume which can be conveyed with the metering pump in the given time, which change in the liquid volume is non-proportional to the change in the input signal.

Methods for operating a decoupled long stroke pump to pump treatment fluid to a wellbore are provided. The decoupled long stroke pump has relatively long stroke plungers that can be powered by hydraulics, linear electric motors, mechanical long stroke mechanisms, linear actuators, or any other device that can provide a linear force to the plungers. Such long stroke pumps have the suction and discharge strokes decoupled such that an absolute linear flow rate without pressure pulses on the suction or discharge can be produced. Any desired flow profile of the treatment fluid can be produced via the decoupled long stroke pump.

A metering pump for dispensing a fuel additive includes a pump body, an inlet and an outlet at which fuel additive respectively enters and exits the metering pump, a piston contained within a piston bore and being configured to draw fuel additive into the metering pump through the inlet and to dispense fuel additive from the metering pump through the outlet, an inflow valve configured to permit fuel additive to flow in a single direction away from the inlet and to prevent fuel additive from flowing in an opposite direction back into the inlet, and an outflow valve configured to permit fuel additive to flow in the single direction towards the outlet, wherein the metering pump has a configuration in which the inlet, the outlet, the piston, the piston bore, the inflow valve, and the outflow valve are centrally positioned along a central plane of the pump body.

A metering pump for dispensing a fuel additive includes a pump body, an inlet and an outlet at which fuel additive respectively enters and exits the metering pump, a piston contained within a piston bore and being configured to draw fuel additive into the metering pump through the inlet and to dispense fuel additive from the metering pump through the outlet, an inflow valve configured to permit fuel additive to flow in a single direction away from the inlet and to prevent fuel additive from flowing in an opposite direction back into the inlet, and an outflow valve configured to permit fuel additive to flow in the single direction towards the outlet, wherein the metering pump has a configuration in which the inlet, the outlet, the piston, the piston bore, the inflow valve, and the outflow valve are centrally positioned along a central plane of the pump body.

A hydraulically operated compressor has a fixed piston and a fixed compression or outer cylinder. A drive or intermediate cylinder is located between the piston and outer cylinder. A compression chamber is formed between the drive cylinder and the outer cylinder. Drive fluid is pumped into and released from an interior chamber in the drive cylinder to reciprocate the drive cylinder. The drive fluid also provides cooling to the interior of the compressor.

A hydraulically operated compressor has a fixed piston and a fixed compression or outer cylinder. A drive or intermediate cylinder is located between the piston and outer cylinder. A compression chamber is formed between the drive cylinder and the outer cylinder. Drive fluid is pumped into and released from an interior chamber in the drive cylinder to reciprocate the drive cylinder. The drive fluid also provides cooling to the interior of the compressor.

A capacity control valve V includes a valve housing, a primary valve opened and closed by a driving force of a solenoid, a pressure-sensitive valve disposed in a pressure-sensitive chamber, and a differential pressure valve opened and closed by a differential pressure valve body moved by a pressure. A control port and a suction port communicate with each other through an intermediate communication path by opening and closing the pressure-sensitive valve. An adapter is provided with an accommodation portion accommodating a differential pressure valve body, and first urging member and a second urging member are interposed in the accommodation portion on both sides of the differential pressure valve in an opening and closing direction with the differential pressure valve body interposed therebetween.

An eccentric sleeve for a crankshaft of a compressor, a crankshaft, a crankshaft assembly, and a compressor are provided. The crankshaft has a main shaft, a counterbalance and an eccentric shaft. The main shaft and the eccentric shaft are provided at two sides of the counterbalance and arranged eccentrically. The main shaft is internally provided with a main lubrication oil passage. An outer circumferential wall of the eccentric shaft is provided with an oil leakage hole in fluid communication with the main lubrication oil passage. The eccentric sleeve is fitted over the eccentric shaft. An outer circumferential wall of the eccentric sleeve is provided with a shaft flow hole extending through the outer circumferential wall in a thickness direction of the eccentric sleeve.

The disclosure relates to a position detection device for determining the position of the diaphragm or the drive piston of an electric-motor-driven diaphragm pump, in particular detecting the upper and lower reversal point (Po, Pu) in the movement curve of the diaphragm of a diaphragm pump operated in an electric-motor-driven manner via eccentric means, wherein a diaphragm actuated by a drive connecting rod closes a conveying chamber with valve means provided on an inlet and outlet side such that the volume can be changed between a minimum and maximum volume, whereby a reciprocating movement of an electric motor having a rotor attached to a shaft is converted into an actuation movement of the drive connecting rod via the effect of the eccentric means, wherein the position detection device has detecting means for detecting the average value position of the rotor shaft, as well as an evaluation device in order to determine at least the position of the upper reversal point of the diaphragm from the average value position.

A capacity control valve (1) for controlling a flow rate or pressure of a variable capacity compressor according to a valve opening degree of a valve section includes: a valve main body (10) having a first valve chamber (14), a second valve chamber (15) and an interior space (16); a valve body (21) having an intermediate communication passage (26) for allowing communication between the first valve chamber and the interior space, a first valve part (21c1) arranged in the first valve chamber, a second valve part (21b1) for opening and closing communication between the interior space and the second valve chamber, and a shaft part (21a) arranged in the interior space; a solenoid (30); a pressure-sensitive body (22) arranged in the interior space; and an auxiliary communication part (21f) which is arranged in the interior space and which allows communication between the interior space and the intermediate communication passage.