Patent attributes
A magnetic drill is provided with an alternate power source. The drill is comprises of: an electric motor for driving a tool; a controller configured to receive an AC input signal and operable to control a drive signal to the electric motor; an electromagnet arranged in a base of the drill housing and operable, in response to a DC voltage, to magnetically couple the base to a surface proximate to the base; an AC/DC converter configured to receive the AC input signal and operates, independent from the controller and in the presence of the AC input signal, to output a DC voltage to the electromagnet; and an alternate power source circuit that monitors the DC voltage output by the converter and, in the absence thereof, provides an alternate DC voltage to the electromagnet.
