A lubricant recovery system for vacuum pump comprising a reservoir to store lubricant. Supply lines connected to the reservoir wherein the supply line can be connected to the vacuum pump to supply the lubricant to the vacuum pump. Further, a return line is connected to the reservoir to return a lubricant-air mixture from the vacuum pump to the reservoir by the return line. An air filter is disposed inside the reservoir to separate lubricant from the air wherein the filter is connected to a scavenge line which is connectable to a low-pressure region of the vacuum pump such that lubricant separated from the lubricant-air mixture by the air filter is drawn via the scavenge line into the vacuum pump. In accordance to the present invention a valve is disposed in the scavenge line to selectively separate the air filter from the vacuum pump.

Disclosed is a safety-reinforced water-ring vacuum pump including a built-in hogging flow path. The water-ring vacuum pump includes a first-stage body, a second-stage body, and an impeller. The first-stage body includes a gas inlet port through which gas is suctioned and a seal water supply port through which seal water is supplied. The second-stage body includes a mixed fluid outlet port through which a mixed fluid of the gas and the seal water is discharged. The impeller is rotated at high speed by an internal drive shaft penetrating the first-stage body and the second-stage body. The first-stage body has a fluid-mixing space provided therein, the fluid-mixing space having a mixed flow of the gas and the seal water therein. The second-stage body has a fluid guide space and an internal hogging flow path provided therein, the internal hogging flow path communicating with the fluid guide space.

An electrically driven positive displacement compressor includes an electric drive motor configured to drive the compressor, the electric drive motor including a ring shaped electric stator and an electric rotor arranged inside the ring shaped electric stator and defining a cavity within the electric rotor. The compressor also includes a working chamber having an inlet and an outlet, the working chamber being arranged at least partially inside the cavity of the electric rotor. The compressor additionally includes a compressor rotor arranged inside the working chamber and coupled to the electric rotor.

Durability of a vacuum pump is prevented from degrading by suppressing abrasion of a rotor and a side plate. The vacuum pump has a hollow cylinder chamber S having an opening at an end portion of a casing body, a rotor which is rotationally driven in the cylinder chamber S, a side plate for blocking the opening of the cylinder chamber S, and a pump cover which is disposed at the opposite side to the rotor so as to sandwich the side plate between the pump cover and the rotor, and the side plate is provided with an intercommunication port which confronts a shaft hole of the rotor and intercommunicates with a space between the side plate and the pump cover.

A vacuum system having a condenser and a root vacuum pump set includes an independent inlet condenser set having an inlet end for receiving vapor inputted from an output of an air cooling power generator condenser of a generator; air in the vapor being condensed, and the surplus air is outputted; a root vacuum pump set including a plurality of root vacuum pumps; the root vacuum pump set further including an input end and an output end; the input end being connected to the independent inlet condenser set; air outputted from the independent inlet condenser set being inputted to the plurality of root vacuum pump for compression and then the compressed air being outputted from the output end; and a backing pump connected to the output end of the root vacuum pump set by using an output pipe; the backing pump serving to receive air outputted from the root vacuum pump set.

A pump includes a pump chamber in which a rotor with gates is supported so that it can rotate, an electric motor for driving the rotor, an outlet, and an inlet port that is fastened to a mounting plate and is in active connection with an inlet channel. The pump should be improved so that its service life and reliability are improved with minimal installation complexity in a vehicle, wherein intense cleaning of lines and devices connected on the suction side can be eliminated. This is achieved in that a filter is arranged in the area of the inlet channel between the mounting plate and the pump chamber.

A rotor for a multi-stage vacuum pump, a multi-stage vacuum pump and a method. The rotor comprises: a plurality of rotary vanes, the plurality of rotary vanes being axially displaced and coaxially aligned; a pair of end shafts, each end shaft extending from opposing axial ends of the plurality of rotary vanes; and an inter-vane shaft extending between adjacent rotary vanes of the plurality of rotary vanes, the inter-vane shaft having a diameter which is greater than that of the end shafts. In this way, the inter-vane shaft provided between each rotary vane may have an increased diameter, which improves the stiffness of the shaft and changes the modal frequency of the rotor. Such a change in the modal frequency is typically sufficient to improve its operation.

A vane pump with a pump housing in which a cam ring is constructed or arranged, and wherein a rotor is provided that is mounted in the cam ring so that it can rotate about a rotational axis , wherein the cam ring has an inner contour with a variable radius that varies between a maximum radius and a minimum radius in the circumferential direction about the rotational axis , wherein, in the radial gap between the inner contour and the rotor , a number of lift sections is constructed with pump chambers constructed in these sections, and wherein vane elements are mounted on the rotor , wherein these elements slide against the inner contour of the cam ring and limit the pump chambers in the circumferential direction. According to the invention, the radius of the inner contour varies about the rotational axis according to the function: r=r.sub.0+a.Math.sin(n.Math.φ), where r.sub.0=(r.sub.max+r.sub.min)/2, a =(r.sub.max−r.sub.min)/2, and φ=phase angle of the radius (r) between (r.sub.min) and (r.sub.max) in the direction of rotation of the rotor .

A control device that controls a target vacuum pump including a motor, including: a decision unit that decides, using at least one of target state quantities at a time of a past stop process of the target vacuum pump or another vacuum pump wherein the target state quantities are state quantities which fluctuate in accordance with a load at a time of a process of stopping a vacuum pump, a normal fluctuation range or a normal time fluctuation behavior of the target state quantity at the time of the stop process; and a control unit that controls the motor, wherein the control unit compares the target state quantity at the time of the process of stopping the target vacuum pump with the normal fluctuation range or the normal time fluctuation behavior, and changes a method of controlling the motor during the stop process depending on the comparison result.

There is disclosed a pump apparatus which can more accurately determine the occurrence of an abnormal vibration. The pump apparatus includes: a pump; an electric motor for driving the pump; an inverter as a speed changing means for the electric motor; a vibration detector for detecting at least one of a vibration of the pump, a vibration of the electric motor and a vibration of the inverter; and a controller for controlling the pump. The controller includes a storage unit for storing a measured vibration value measured by the vibration detector. The storage unit has a storage table which, when the rotational speed of the pump is increased stepwise to a predetermined rotational speed, stores the measured vibration value measured at each step.