Patent ID: 6286609
Filing Date: 2001-09-11
Classification: B25F,H02H,H02J,H02M,H02P

Abstract:
A corded/cordless system for power tools comprising:a low-voltage DC power tool operable in a preselected voltage range, said power tool having;an exterior, an interior, a pre-defined interface for mechanically and electrically mating with a power module having a source of electric power, and a motor of a predetermined rating having a predetermined minimum inductance; anda chopper module to convert input power from the source of electric power to an average DC motor voltage in the preselected voltage range suitable for powering the low-voltage DC power tool, said chopper module including a chopper circuit operable at a predetermined switching frequency to convert the input power to an output voltage comprising a series of voltage pulses that are averaged across the motor predetermined minimum inductance, thereby supplying the average DC motor voltage to the motor.