An operating method for a conveying device with an eccentric screw pump for conveying viscous construction materials comprising sensing a pressure of the construction material at an outlet of the eccentric screw pump when the eccentric screw pump is running and automatically switching off the eccentric screw pump if the pressure exceeds an upper limit value, otherwise continued operation of the eccentric screw pump. The method includes sensing a characteristic variable of the running eccentric screw pump and comparison of the characteristic variable with a first comparison variable, which is characteristic of operation with an open dispensing device and/or with a second comparison variable, which is characteristic of operation with a closed dispensing device, and switching off the eccentric screw pump if operation with a closed dispensing device is detected, otherwise continued operation of the eccentric screw pump.

Variable capacity vane pump 1 supplying working fluid to power steering device of vehicle has pump housing 2 formed from bottomed cylindrical-shaped front housing 5 and rear housing 6 closing the front housing, pump element 3 accommodated in pump housing, communicating with inlet passage 23 and with outlet passage 30 and sucking and discharging working fluid, and flow amount control valve 33 controlling an amount of working fluid discharged by pump element. Pressure-sensitive valve 50, which changes a flow passage cross-sectional area of the outlet passage so that the discharge amount of the pump element is increased with increase in load pressure of power steering device, is set at some midpoint of the outlet passage and at bottom wall portion 5b of front housing. It is therefore possible to suppress increase in size of device while reducing energy loss when variable capacity vane pump is mounted in power steering device.

A seal assembly for sealing a pump shaft in a rotary piston pump configured for conveying pump-conveyed fluid comprises a sealing-fluid pump device having a pump inlet and a pump outlet. A blocking chamber is connected to the pump outlet and is disposed so as to neighbor the pump chamber of the rotary piston pump and is sealed in relation to the pump chamber by means of a first shaft seal that encloses the pump shaft. The blocking chamber by way of the pump outlet is impinged with a fluid pressure resulting from the fluid pressure differential that is generated by the sealing-fluid pump device, whereby said fluid pressure interacts with the first seal assembly to seal the pump chamber in relation to the egress of pump-conveyed fluid from the pump chamber along the pump shaft.

The present disclosure relates to a scroll compressor, and it is possible to constitute a depressurized resistance value of a first orifice disposed on an oil recovery part to be lower than a depressurized resistance value of a second orifice, thereby maintaining/enhancing volume efficiency upon driving under a high pressure condition where a pressure of discharged refrigerant is high by increasing the back pressure of a back pressure chamber.

An embodiment of a system with a minute measure of pulsatility in a flow of a fluid is described that comprises a first pump configured to flow the fluid to a junction at a first flow rate that comprises a measure of pulsatility; and a second pump configured to flow a portion of the fluid from the junction at a second flow rate that is less than the first flow rate to produce a flow of the fluid at a third flow rate from the junction with a minute measure of pulsatility.

A compressor includes a bore, a rotor disposed within the bore, a compressor inlet, a compressor outlet and a compression chamber defined between the bore and the rotor. A volume of the compression chamber gradually reduces from the compressor inlet to the compressor outlet. An economizer is configured to fluidically connect to the compression chamber. The economizer is configured to inject a working fluid into the compression chamber at an injection position. The injection position is changeable according to a working condition of the compressor.

A self adjusting gear pump (10) for an ice cream freezer and a control unit (20) for adaptively controlling the closing pressure (PCLOSE) of a pump for an ice cream freezer. The gear pump system comprises a pump casing (11), an inlet (12) for receiving a liquid food product of ice cream mix, an outlet (15) for transferring the ice cream mix into a freezing cylinder (41) of the ice cream freezer (40), wherein the pump (10) is closed by supplying a closing air pressure onto a moveable pump cover (16) of the pump via at least one hole (191, 192) provided straight through the pump casing (11), thereby moving said moveable pump cover (16) against the star wheel (14) and a control unit (20) for supplying a calculated closing air pressure (PCLOSE) to the pump by means of the air pressure regulator (100).

A compressor includes a bore, a rotor disposed within the bore, a compressor inlet, a compressor outlet and a compression chamber defined between the bore and the rotor. A volume of the compression chamber gradually reduces from the compressor inlet to the compressor outlet. An economizer is configured to fluidically connect to the compression chamber. The economizer is configured to inject a working fluid into the compression chamber at an injection position. The injection position is changeable according to a working condition of the compressor.

The present disclosure relates to a scroll compressor, and it is possible to constitute a depressurized resistance value of a first orifice disposed on an oil recovery part to be lower than a depressurized resistance value of a second orifice, thereby maintaining/enhancing volume efficiency upon driving under a high pressure condition where a pressure of discharged refrigerant is high by increasing the back pressure of a back pressure chamber.

An embodiment of a system with a minute measure of pulsatility in a flow of a fluid is described that comprises a first pump configured to flow the fluid to a junction at a first flow rate that comprises a measure of pulsatility; and a second pump configured to flow a portion of the fluid from the junction at a second flow rate that is less than the first flow rate to produce a flow of the fluid at a third flow rate from the junction with a minute measure of pulsatility.