Patent ID: 9401670
Filing Date: 2016-07-26
CPC Classification: F04B,H02P

Claim Text:
1. An electric pump, comprising: a pump body pumping up and discharging an operation fluid; a sensorless brushless motor driving the pump body; and an electronic control unit controlling the motor to perform a constant current control and a constant voltage control to discharge a necessary discharge amount of the operation fluid from the pump body, the electronic control unit controlling the motor to switch from the constant current control to the constant voltage control at a predetermined temperature of the operation fluid and at a predetermined motor applied voltage, wherein the electronic control unit controls the motor to switch from the constant current control to the constant voltage control, wherein at switching, the electronic control unit increases linearly the motor applied voltage to a motor applied voltage that is higher than the predetermined motor applied voltage when a temperature of the operation fluid is lower than the predetermined temperature to discharge the necessary discharge amount of the operation fluid from the pump body.