A pump arrangement for pumping a liquid, in particular a liquid contaminated with dirt particles, the pump arrangement having at least one working chamber (1, 2, 11, 12) and at least one delivery piston (3, 4, 13), and at least one inlet valve (7) and at least one outlet valve (8), and the delivery piston (3, 4, 13) being movable in order to suck liquid into the working chamber (1, 2, 11, 12) through the inlet valve (7) and to eject liquid out of the working chamber (1, 2, 11, 12) through the outlet valve (8), and the pump arrangement having a wear-monitoring device (40) for monitoring the wear on the inlet valve (7) and/or outlet valve (8) with at least one pressure sensor (41) and one pressure evaluation unit (42) for processing pressure measurement values output from the pressure sensor (41), wherein the pump arrangement, for the purpose of moving the delivery piston (3, 4, 13), has a drive fluid system (20) that can be operated with a drive fluid, and the pressure sensor (41) of the wear-monitoring device (40) is arranged to detect the pressure of the drive fluid in the drive fluid system (20).

A pump arrangement for pumping a liquid, in particular a liquid contaminated with dirt particles, the pump arrangement having at least one working chamber (1, 2, 11, 12) and at least one delivery piston (3, 4, 13), and at least one inlet valve (7) and at least one outlet valve (8), and the delivery piston (3, 4, 13) being movable in order to suck liquid into the working chamber (1, 2, 11, 12) through the inlet valve (7) and to eject liquid out of the working chamber (1, 2, 11, 12) through the outlet valve (8), and the pump arrangement having a wear-monitoring device (40) for monitoring the wear on the inlet valve (7) and/or outlet valve (8) with at least one pressure sensor (41) and one pressure evaluation unit (42) for processing pressure measurement values output from the pressure sensor (41), wherein the pump arrangement, for the purpose of moving the delivery piston (3, 4, 13), has a drive fluid system (20) that can be operated with a drive fluid, and the pressure sensor (41) of the wear-monitoring device (40) is arranged to detect the pressure of the drive fluid in the drive fluid system (20).

A fracturing apparatus is provided. The fracturing apparatus includes: a plunger pump including a hydraulic end and a power end, the power end having a power end oil outlet and at least one power end oil inlet that are coupled to each other; and a power end lubricating system, including: a lubricating oil tank configured for defining an accommodation space, at least one lubrication pump having a lubrication pump oil inlet and a lubrication pump oil outlet that are coupled to each other, and at least one lubrication motor configured for providing power for the at least one lubrication pump, wherein at least a portion of at least one of the lubrication motor and the lubrication pump is located in the accommodation space.

A fracturing apparatus is provided. The fracturing apparatus includes: a plunger pump including a hydraulic end and a power end, the power end having a power end oil outlet and at least one power end oil inlet that are coupled to each other; and a power end lubricating system, including: a lubricating oil tank configured for defining an accommodation space, at least one lubrication pump having a lubrication pump oil inlet and a lubrication pump oil outlet that are coupled to each other, and at least one lubrication motor configured for providing power for the at least one lubrication pump, wherein at least a portion of at least one of the lubrication motor and the lubrication pump is located in the accommodation space.

A pump including one or more pumping chambers, one or more drive mechanisms for driving the one or more pumping chambers and a logic arrangement. The first pumping chamber of the one or more pumping chambers has a first inlet check valve, a first outlet check valve and a first temperature sensor. The logic arrangement is configured to identify a leak by applying logic to at least resistance-data indicative of a resistance of the first pumping chamber to the driving and temperature-data at least based on output from the first temperature sensor.

A switch (10, 200) is provided for installation in the air conditioning (A/C) system (12) in a vehicle (16) for intermittently operating the clutch (20) in the A/C system (12) each time the control (44) in the A/C system (12) provides power to operate the clutch (20) to prevent slugging. This turns the compressor (14) a few turns each time the clutch (20) is energized during intermittent operation to purge liquid refrigerant and lubricant from the compressor (14) to prevent slugging. The switch (10, 200) can be installed in existing vehicles by connecting the switch (10, 200) in the wiring harness (18) of the A/C system (12) to the power lead (38) from the control (44) to the clutch (20) and between the ground lead (40) from the clutch (20) and a ground. The switch (10, 200) can include a microcontroller (52) for controlling the operation of a power transistor (70) to intermittently ground the clutch to provide the intermittent operation. A battery (202) can be provided to power the microcontroller (52) for a set period of time after an initial intermittent operation. This prevents additional intermittent operation for the set period of time.

A leak-current detecting unit detects a zero-phase current flowing from an electric-motor driving device, which drives an electric motor with electric power from an alternating-current power supply, or the electric motor to a ground, a leak-current control unit that, on the basis of the zero-phase current detected by the leak-current detecting unit, generates a control signal having cyclicity synchronized with the alternating-current power supply, and an anti-phase generating unit that generates an anti-phase current that is in anti-phase to the zero-phase current on the basis of the control signal from the leak-current control unit, and outputs the anti-phase current.

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.

An information processing system includes a terminal apparatus that sends the received machine-type identification information and state history information received from the monitoring target apparatus by near field communication, an information processing apparatus that receives the machine-type identification information and the state history information from the terminal apparatus, and a storage apparatus that accumulates machine-type identification information identifying a machine type of a monitoring target apparatus and normal-state history information in an associated manner. When the information processing apparatus receives the machine-type identification information and state history information about a certain monitoring target apparatus from the terminal apparatus, the information processing apparatus compares the normal-state history information accumulated in the storage apparatus in association with the machine-type identification information and the received state history information, judges whether an operation state of the monitoring target apparatus is normal, and sends a judgment result to the terminal apparatus.

An information processing system includes a terminal apparatus that sends the received machine-type identification information and state history information received from the monitoring target apparatus by near field communication, an information processing apparatus that receives the machine-type identification information and the state history information from the terminal apparatus, and a storage apparatus that accumulates machine-type identification information identifying a machine type of a monitoring target apparatus and normal-state history information in an associated manner. When the information processing apparatus receives the machine-type identification information and state history information about a certain monitoring target apparatus from the terminal apparatus, the information processing apparatus compares the normal-state history information accumulated in the storage apparatus in association with the machine-type identification information and the received state history information, judges whether an operation state of the monitoring target apparatus is normal, and sends a judgment result to the terminal apparatus.