DOSING PUMP AND METHOD FOR ENHANCING DOSING PRECISION

摘要

The invention relates to a method for increasing the dosing precisionof a dosing pump which is driven by an asynchronous motor via aneccentric gear. A supply voltage to the motor is switched on for driving thedosing pump for an actuation interval. The supply of the motor is switchedoff about half a cycle time before it is required to stop the motor toterminate dosing by the dosing pump. The motor is allowed to run freely inan unpowered mode for about one quarter of the cycle time after theswitching off step and a DC voltage is applied to it for approximately thenext one quarter cycle time to induce an eddy current is induced in a rotorof the motor to generate a counter-magnetic field for braking the rotor to astand still.