A method of controlling an electric oil pump configured for a vehicle, may include a step of determining whether a vehicle has entered a sloped road, a step of determining whether a drive motor of the vehicle is in one or more overheatable conditions when it is determined that the vehicle has entered a sloped road, a step of determining whether the overheatable condition is maintained over a preset reference time when it is determined that the vehicle is in the over-heatable condition; and a step of supplying a pulse to an RPM input for the electric oil pump when it is determined that the duration of the over-heatable condition exceeds the preset reference time.

Provided is a compressor capable of calculating the correct time remaining before maintenance. The compressor is provided with: a compressor body that compresses fluid; a motor that drives the compressor body; a temperature sensor that detects the temperature of the compressor; a pressure sensor that detects the pressure of the compressed fluid outputted from the compressor body; and a calculation unit that calculates the time remaining before maintenance for the compressor body, using the temperature of the compressor and the pressure of the compressed fluid assigned with respective predetermined weights. The calculation unit changes the weighting of the temperature according to the pressure of the compressed fluid or the operation rate of the compressor body.

This disclosure relates to a system for reducing cavitation at a surface that moves relatively with respect to a first fluid. The system comprises a degasser configured to at least partially degas a second fluid. The system also comprises a reservoir in communication with the degasser and configured to house the at least partially degassed second fluid, the reservoir having an outlet that is arranged for directing the second fluid towards the surface. The system is configured such that the directing of the at least partially degassed second fluid towards the surface forms a boundary layer at the surface. The boundary layer is adapted to at least partially increase the negative pressure required to initiate cavitation at the surface so as to reduce the occurrence of cavitation during such relative movement.

A linear compressor according to the present disclosure may include a cylinder provided with at least one groove, a piston reciprocating within the cylinder, a motor configured to provide a driving force to move the piston within the cylinder, an inverter configured to perform a switching operation to transmit electric power to the motor, and a controller configured to receive temperature information from the electronic device and control the inverter to preheat the motor based on the received temperature information.

A method of driving a pump is used in a pressure-applying apparatus, the apparatus including a flow passage, a pump configured to impart pressure into the flow passage, an opening and closing valve configured to open and close the flow passage, a pressure detector configured to detect pressure in the flow passage, and an atmospheric air open valve configured to open an interior of the flow passage to atmospheric air. The method includes driving the pump after closing the opening and closing valve and opening the atmospheric air open valve, and evaluating a state of the pump, based on one of: the pressure detected by the pressure detector at a time at which a predetermined time period has elapsed after closing the atmospheric air open valve, and a time from closing of the atmospheric air open valve until detection of a predetermined pressure by the pressure detector.

A method of controlling an electric oil pump configured for a vehicle, may include a step of determining whether a vehicle has entered a sloped road, a step of determining whether a drive motor of the vehicle is in one or more overheatable conditions when it is determined that the vehicle has entered a sloped road, a step of determining whether the overheatable condition is maintained over a preset reference time when it is determined that the vehicle is in the over-heatable condition; and a step of supplying a pulse to an RPM input for the electric oil pump when it is determined that the duration of the over-heatable condition exceeds the preset reference time.

The invention relates to a method and a device for controlling the delivery rate (P.sub.Q) of a concrete pump (1) for filling a formwork arrangement (2) with a pumpable filling compound (3) as a function of curing-relevant material and environmental parameters (RST), after which the installed filling compound (3) sets within the formwork arrangement (2), comprising the following steps: determining a permissible climbing speed (vsz) for filling the formwork arrangement (2) with the filling compound (3) on the basis of the material and ambient parameters (RST), measuring the static filling compound pressure (p.sub.F) acting on the formwork arrangement (2) during filling, calculating the permissible delivery rate (P.sub.Q) of the concrete pump (1) as a function of the determined permissible rate of ascent (vsz) and the measured static filling compound pressure (p.sub.F) at the formwork arrangement (2).

A drive system for a fluid displacement pump includes an electric motor, a drive coupled to the rotor at a first end of the electric motor, a pump including a fluid displacement member mechanically coupled to the drive, and a controller configured to control a level of power to the electric motor based on a pressure setting set by a user. The electric motor includes a stator and a rotor disposed on an axis. The drive coupled to the rotor converts the rotational output to a linear, reciprocating input to power a pump.

A drive system for a fluid displacement pump includes an electric motor, a drive coupled to the rotor at a first end of the electric motor, a fluid displacement member mechanically coupled to the drive, and a pump frame mechanically coupled to the electric motor. The electric motor includes a stator and a rotor disposed on an axis. The drive coupled to the rotor converts the rotational output to a linear, reciprocating input to the fluid displacement member. The rotor is disposed about the stator to rotate about the stator.

A control module for a refrigeration system includes a startup mode control module that receives an off time of a compressor and an ambient temperature, determines whether the off time and the ambient temperature indicate that the compressor is in a flooded condition, and selects, based on the determination, between a normal startup mode and a flooded startup mode. A compressor control module transitions from the flooded startup mode to the normal startup mode after a predetermined period associated with operating in the flooded startup mode and operates the compressor at a first speed in the normal startup mode and operates the compressor at a second speed less than the first speed in the flooded startup mode.