Patent ID: 6320339
Filing Date: 2001-11-20
Classification: H02P,Y10S

Abstract:
A control device for controlling current passing through a motor, comprising:a power module adapted to be connected to the motor and a power supply unit;a current sensor connected to said power module for generating an electric signal corresponding to magnitude of the current passing through the motor;a first current detecting circuit connected to said current sensor and said power module, said first current detecting circuit determining whether the current passing through the motor is larger than a first predetermined value according to the electric signal from said current sensor, and generating a first flag signal that is provided to said power module so as to inhibit connection between the motor and the power supply unit upon detection that the current passing through the motor is larger than the first predetermined value;a second current detecting circuit connected to said current sensor and said power module, said second current detecting circuit determining whether the current passing through the motor is larger than a second predetermined value according to the electric signal from said current sensor, and generating a second flag signal that is provided to said power module so as to inhibit connection between the motor and the power supply unit upon detection that the current passing through the motor is larger than the second predetermined value, wherein the second predetermined value is larger than the first predetermined value; anda processor connected to said first and second current detecting circuits, said processor generating a first flag reset signal to said first current detecting circuit at a first reset frequency for resetting the first flag signal periodically, said processor further generating a second flag reset signal to said second current detecting circuit at a second reset frequency for resetting the second flag signal periodically, wherein the first reset frequency is larger than the second reset frequency;whereby, connection between the motor and the power supply unit is inhibited for a period of time that is longer when the second flag signal is provided to said power module than when the first flag signal is provided to said power module.