A lubricant-sealed vacuum pump configured to pump fluid from an inlet to an exhaust, method and filter are disclosed. The lubricant-sealed vacuum pump comprises: a rotor; a filter for filtering lubricant from fluid to be output by the pump; control circuitry for controlling a speed of rotation of the rotor, the control circuitry being configured to control rotation of the rotor, such that the rotor rotates at a reduced speed initially when a pressure at the inlet is high and rotates at a higher operational speed when the pressure at the inlet has reduced.

The invention relates to a method for controlling a rotary screw compressor, having at least a first and a second air-end, wherein both air-ends are driven separately from one another and speed controlled. According to the invention, the following steps are carried out: detection of a volume flow taken at the outlet of the second air-end; adjustment of the rotational speed of both air-ends, when the removed volume flow fluctuates in a range between a maximum value and a minimum value; opening of a pressure-relief valve, if the volume flow falls below the minimum value; and reduction of the rotational speed of at least the first air-end to a predetermined idling speed (V1.sub.L) to reduce the volumetric flow delivered by the first to the second air-end.

A sealed compressor includes a centrifugal impeller above a rotor to synchronously rotate. A refrigerant rises through a rotor air hole, flows in an upper space, and flows out from a discharge pipe. The centrifugal impeller includes an oil separation plate on the rotor, and plural vanes standing on the oil separation plate, and forms inter-vane flow passages between adjacent vanes, and a vane inner flow passage that guides refrigerant from the rotor air hole to inner entrances of the inter-vane flow passages. Outer exits of the inter-vane flow passages are disposed along an entire circumference, and refrigerant increased in pressure while passing through the inter-vane flow passages flows out from the outer exits to the upper space. The oil separation plate closes a short-circuit passage through which the refrigerant directly flows from the vane inner flow passages to the discharge pipe without passing through the inter-vane flow passages.

A method of measuring fluid flow in a system includes providing a fluid supply assembly which includes a fluid supply supplying fluid, a dispensing valve from which the fluid is dispensed, a dispensing line connecting the fluid supply to the dispensing valve, a gear pump including a motor and a gear being rotated by the motor to provide a flow of fluid from the fluid supply to the dispensing line, a revolution counter counting a number of revolutions of an element of the gear pump, a pressure transducer coupled to the dispensing line sensing pressure in the system, and a controller including a processor and a memory to control the system. The method further includes directing fluid from the fluid supply, rotating the gear to provide the flow of fluid from the fluid supply to the dispensing line, and providing a calibration process by modulating the gear pump.

A method of measuring fluid flow in a system includes providing a fluid supply assembly which includes a fluid supply supplying fluid, a dispensing valve from which the fluid is dispensed, a dispensing line connecting the fluid supply to the dispensing valve, a gear pump including a motor and a gear being rotated by the motor to provide a flow of fluid from the fluid supply to the dispensing line, a revolution counter counting a number of revolutions of an element of the gear pump, a pressure transducer coupled to the dispensing line sensing pressure in the system, and a controller including a processor and a memory to control the system. The method further includes directing fluid from the fluid supply, rotating the gear to provide the flow of fluid from the fluid supply to the dispensing line, and providing a calibration process by modulating the gear pump.

Assemblies, apparatuses, and methods to extract or convey a material from a source of the material may include a vacuum generation and sound attenuation assembly. The vacuum generation and sound attenuation assembly may include a compressor housing having a vacuum source, a cooling system, and a vacuum controller. The vacuum source may include a compressor powered by an electric motor and positioned to cause a vacuum flow between the source of the material, and the vacuum generation and sound attenuation assembly. The vacuum generation and sound attenuation assembly may further include a sound attenuation chamber positioned to receive at least a portion of the vacuum flow from, and attenuate sound generated by, the vacuum source. The compressor housing and sound attenuation chamber of the vacuum generation and sound attenuation assembly may be arranged compactly on a common chassis for ease of transport and deployment.

The invention relates to a method for controlling a rotary screw compressor, having at least a first and a second air-end, wherein both air-ends are driven separately from one another and speed controlled. According to the invention, the following steps are carried out: detection of a volume flow taken at the outlet of the second air-end; adjustment of the rotational speed of both air-ends, when the removed volume flow fluctuates in a range between a maximum value and a minimum value; opening of a pressure-relief valve, if the volume flow falls below the minimum value; and reduction of the rotational speed of at least the first air-end to a predetermined idling speed (V1.sub.L) to reduce the volumetric flow delivered by the first to the second air-end.

A gerotor pump includes a pump head including a configuration of gerotors for pumping in operation a fluid medium from an input port arrangement to an output port arrangement, and a motor arrangement for providing mechanical power in operation for actuating the configuration of gerotors. The configuration of gerotors includes an outer gerotor and an inner gerotor that are operable to cooperate to entrap and propel the fluid medium from the input port arrangement to the output port arrangement. At least one of the outer gerotor and the inner gerotor are fabricated from a flexible material and/or are internally structured so as to exhibit a flexible peripheral exterior surface in operation. Moreover, the outer gerotor and the inner gerotor are loaded and/or are assembled together in a preloaded state, within the pump head, so that a gap formed between the gerotors whereat they mutually cooperate for entrapping and propelling the fluid medium is maintained in a flexibly compressed state when the pump is in operation. Optionally, at least one of the outer and inner gerotors is fabricated as a hybrid component including regions of a flexible material therein, and regions of an inflexible material therein. More optionally, the flexible material has a Young's modulus in a range of 1 MegaPascal (MPa) to 5 GigaPascals (GPa), and the inflexible material has a Young's modulus in a range of 2 GPa to 420 GPa. Optionally, at least one gerotor gerotor pump is includes in a gerotor pump apparatus that includes a pulse attenuating arrangement at an output port of the gerotor pump apparatus for attenuating periodic pulses and fluctuations in a fluid flow provided in use at the output port.

Assemblies, apparatuses, and methods to extract or convey a material from a source of the material may include a vacuum generation and sound attenuation assembly. The vacuum generation and sound attenuation assembly may include a compressor housing having a vacuum source, a cooling system, and a vacuum controller. The vacuum source may include a compressor powered by an electric motor and positioned to cause a vacuum flow between the source of the material, and the vacuum generation and sound attenuation assembly. The vacuum generation and sound attenuation assembly may further include a sound attenuation chamber positioned to receive at least a portion of the vacuum flow from, and attenuate sound generated by, the vacuum source. The compressor housing and sound attenuation chamber of the vacuum generation and sound attenuation assembly may be arranged compactly on a common chassis for ease of transport and deployment.