Power-operated valve, has control unit for controlling stepper motor with reduced speed at beginning of opening of shutter so that motor exerts maximum force on valve, and for increasing speed of motor after shutter opening

摘要

The valve has a stepper motor (16) controlling a displacement of a shutter (10a) movably mounted in a body (1). A control unit (8) has an electronic control board (17) and controls the motor with a reduced speed value at the beginning of opening of the shutter (10a), such that the motor exerts a maximum force on the shutter. The unit increases the speed of the motor after opening of the shutter.