Patent ID: 6873128
Filing Date: 2005-03-29
Classification: B60H,Y02T

Abstract:
1. A DC motor control device of a water heater, comprising: a fanner control system having a DC motor and a control circuit unit connected to said DC motor, said control circuit unit having a first control circuit for filtering out noises from an input AC source, a second control circuit for phase control of external signals, and a third control circuit having input terminals respectively connected to said first control circuit and said second control circuit and output terminals connected to said DC motor; for rectifying and filtering a first AC voltage outputted from said first control circuit and a second AC voltage outputted from said second control circuit so as to provide a DC voltage to drive said DC motor and control a rotation speed of said DC motor; a rotation speed detection circuit being connected to said DC motor of said fanner control system for detecting the rotation speed of said DC motor; and a micro-processing unit connected to said rotation speed detection circuit and said second control circuit for processing outputs from said rotation speed detection circuit and outputting a control signal to drive said second control circuit to output the second AC voltage.