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.

A method is provided for controlling a temperature of a vacuum pump of a dry vacuum pump type subjected to variable pumping loads, the pump including a stator, a pumping stage, two shafts extending into the stage and respectively bearing a rotor to rotate synchronously in opposite directions in the stator and to drive a gas from a suction inlet to a delivery outlet, a cooling element coupled to the stator, a temperature sensor to measure a stator temperature, and a controller to control the stator temperature by the cooling element and the temperature sensor; and the method including controlling the pump temperature by the cooling element based on a temperature setpoint and a measurement of the stator temperature, and monitoring whether a value of a pumping load parameter is below a load threshold and, if so, increasing the setpoint. A vacuum pump and a system are also provided.

An oil-injected multistage compressor device that comprises at least one low-pressure stage compressor element (2) with an inlet (4a) and an outlet (5a) and a high-pressure stage compressor element (3) with an inlet (4b) and an outlet (5b), whereby the outlet (5a) of the low-pressure stage compressor element (2) is connected to the inlet (4b) of the high-pressure stage compressor element (3) via a conduit (6), characterized in that an intercooler (9) is provided between the low-pressure stage compressor element (2) and the high-pressure stage compressor element (3) in the aforementioned conduit (6) and that the compressor device (1) is also equipped with a restriction (10) for limiting the amount of oil injected in the low-pressure stage compressor element (2).

A fluid pump includes a pump element where rotation of the pump element generates suction at the inlet and pressure at the outlet to move fluid through a fluid path. An inlet orifice directs a portion of the fluid through the accessory fluid path that includes a low-restriction return path providing a continuous flow of the fluid through the accessory fluid path and to an outlet orifice. A circuit board housing includes a contoured portion and a PCB with a thermistor in communication with contoured portion. The continuous flow is directed between the contoured portion and the outlet orifice between a rotor and the outer wall. The low-restriction return path maintains a temperature of the continuous flow of the fluid within the contoured portion of the accessory fluid path to be similar to a temperature of the fluid in the fluid path.

A control system comprising: a suction line; an exhaust line; an operating liquid line; a liquid ring pump comprising a suction input coupled to the suction line, an exhaust output coupled to the exhaust line, and a liquid input coupled to the operating liquid line; a pump configured to pump operating liquid into the liquid ring pump via the operating liquid line and the liquid input; a motor configured to drive the pump; a first sensor configured to measure a first parameter, the first parameter being a parameter of an exhaust fluid of the liquid ring pump; a second sensor configured to measure a second parameter, the second parameter being a parameter of a fluid received by the liquid ring pump; and a controller operatively coupled to the first sensor, the second sensor, and the motor, and configured to control the motor based on sensor measurements of the first sensor and the second sensor. The control system advantageously tends to reduce or eliminate the wear caused by cavitations.

Compressor device comprising an oil-injected compressor element (2) with an outlet (4) connected via an outlet line (8) to an oil separator (9) which is connected via an injection pipe (10) to the compressor element (2), wherein controllable cooling means (15) for the oil are provided, the compressor device (1) being provided with a control unit (21) and thereto connected measuring means (22a, 22b) for controlling the cooling means (15) to control a temperature (T_uit_afsch) downstream of the oil separator (9), the measuring means (22a, 22b) including means (22a) for determining a temperature (T_uit) at the outlet (4) and a temperature sensor (22b) for determining the temperature (T_uit_afsch) downstream of the oil separator (9), the control unit (21) including a controller (25) for controlling the cooling means (15) on the basis of signals from said measuring means (22a, 22b) and on the basis of a dew point.

An electronic oil pump includes a first rotor assembly, a stator assembly, an electric control board assembly, an isolation member and thermal conductive members; the first rotor assembly is located in a first chamber of the electronic oil pump, the thermal conductive members each comprise a first portion and a second portion, the first portions being located in a second chamber of the electronic oil pump, the second portions being located in a third chamber of the electronic oil pump; the electric control board assembly includes a base plate and a temperature-sensing unit, the base plate including first holes, an upper plate layer, a lower plate layer and at least one metal layer, a part of the second portions being located in the first holes; the temperature-sensing unit is located at one side of the second portion, there is a preset distance between the temperature-sensing unit and the second portion.

A control system comprising: a suction line; an exhaust line; an operating liquid line; a liquid ring pump comprising a suction input coupled to the suction line, an exhaust output coupled to the exhaust line, and a liquid input coupled to the operating liquid line; a pump configured to pump operating liquid into the liquid ring pump via the operating liquid line and the liquid input; a motor configured to drive the pump; a first sensor configured to measure a first parameter, the first parameter being a parameter of an exhaust fluid of the liquid ring pump; a second sensor configured to measure a second parameter, the second parameter being a parameter of a fluid received by the liquid ring pump; and a controller operatively coupled to the first sensor, the second sensor, and the motor, and configured to control the motor based on sensor measurements of the first sensor and the second sensor. The control system advantageously tends to reduce or eliminate the wear caused by cavitations.

A fluid pump includes a pump element in communication with an inlet and an outlet. Rotation of the pump element generates a suction at the inlet and pressure at the outlet. The suction and pressure cooperate to move a fluid through a fluid path. An accessory fluid path is in communication with the inlet and outlet. The accessory fluid path includes a thermistor in communication with the accessory fluid path. The thermistor monitors a temperature of the fluid within the accessory fluid path.

A fault-rectification method for an eccentric screw pump of a conveying apparatus for conveying viscous construction materials, comprising the steps of monitoring a start of a conveying operation of the eccentric screw pump by way of a characteristic-variable-monitoring program of a control device of the conveying apparatus, wherein a working-free program is executed by the control device of the eccentric screw pump if, for one or more characteristic variables. The characteristic-variable-monitoring program acquires characteristic-variable values which are stored, alone or in combination with one another, as fault values that indicate jamming of a rotor/stator unit of the eccentric screw pump, and wherein otherwise a conveying operation is begun. The eccentric screw pump is operated in the working-free program in such a way that an electric motor of a drive unit of the conveying apparatus is multiply alternately switched on and switched off.