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 compressor fault diagnostic apparatus including a current sensing unit to sense a current flowing through a motor of the compressor, a fault diagnostic unit to determine whether or not the motor performs a reverse rotation based on the current flowing through the motor, and a cut-off unit to remove power based on a determination of the fault diagnostic unit.

A motor drive control device has a control circuit that generates a drive control signal for controlling a rotational speed of a motor based on a speed command signal indicating a target rotational speed of the motor, and a motor driving unit that drives the motor based on the drive control signal. The control circuit performs speed feedback control for generating the drive control signal so that the rotational speed of the motor coincides with the target rotational speed when the target rotational speed is lower than a rotational speed threshold value, and generates the drive control signal based on a relationship between current flowing through the motor and a reference current value when the target rotational speed is higher than the rotational speed threshold value.

A multi-winding-motor driving system includes a motor and a power unit. The motor has multi-branch windings independent from each other. The power unit includes a rectifier unit and a plurality of inverter units, wherein the inverter units correspond to the multi-branch windings of the motor one to one, and each of the inverter units supplies power to corresponding one branch of the multi-branch windings of the motor.

A system for calibrating an electrohydraulic pump for a vehicle having a propel system that includes an engine connected to the electrohydraulic pump. A micro-controller having software and an input device is connected to a plurality of sensors mounted about the vehicle. The software uses a plurality of parameters to convert internal analog drive signals into analog output signals to control the electrohydraulic pump and motion of the machine where the parameters include a forward start current value and a reverse start current value.

Disclosed are a variable capacity compressor operation mode determination method and device, a variable capacity compressor and an air conditioner. The variable capacity compressor operation mode determination method includes: detecting a current value of a compressor at present as A1 before switching an operation mode of the compressor; detecting the current value of the compressor at present as A2 after switching the operation mode of the compressor and reaching a preset time; comparing A1 and A2, determining that the switching of the operation mode of the compressor is successful when a ratio relationship between A1 and A2 satisfies a preset condition, and determining that switching of the operation mode of the compressor is failed when the ratio relationship between A1 and A2 dissatisfies a preset condition.

A pump having an electric motor (14) and an electronic monitoring circuit (30) arranged in a housing part (26) of the motor, for monitoring and recording operating parameters of the pump, one of the operating parameters being the current consumption of the pump, the monitoring circuit (30) having a digital current and voltage measuring circuit (34) which is integrated in a semiconductor component and has at least one Hall sensor (36) for measuring current.

A pump monitoring system may include a sensor for monitoring a parameter of a pump system. The sensor may include at least one of an ammeter in electrical communication with an electric motor driving a pump and a torque sensor on a drive shaft that drives a pump. The system may also include a controller in data communication with the sensor to receive sensor data. The controller may be configured to assess the performance of the respective pump in one or more ways. At least one of the one or more ways may include reliance on the sensor data from only one sensor to identify valve or seat wear or failure. Alternatively or additionally, at least one of the one or more ways may identify valve or seat wear or failure without reliance on pump output pressure.

A motor drive control device has a control circuit that generates a drive control signal for controlling a rotational speed of a motor based on a speed command signal indicating a target rotational speed of the motor, and a motor driving unit that drives the motor based on the drive control signal. The control circuit performs speed feedback control for generating the drive control signal so that the rotational speed of the motor coincides with the target rotational speed when the target rotational speed is lower than a rotational speed threshold value, and generates the drive control signal based on a relationship between current flowing through the motor and a reference current value when the target rotational speed is higher than the rotational speed threshold value.

There is provided a wobble plate piston water pump including: a pump body defining a plurality of channels; a rotatable wobble plate disposed in the pump body; a plurality of pistons each located in a respective one of the plurality of channels, the pistons being reciprocatable within the channel along a piston axis; a water passage defined by a water inlet and a water outlet; and a plurality of inlet check valves, each associated with one of the channels, and positioned between the water inlet and the associated channel, the inlet check valves reciprocate along an axis parallel to the piston axis to transition between closed states and open states.