US Patent 7752763 Electric drill

An electric drill having a function for preventing drilling of unexpected oblique hole. Further in the electric drill, when the direction of drilling is displaced in drilling work using the electric drill, it is sensed automatically to stop the drilling. The electric drill (1) performs drilling in the direction perpendicular a workpiece (7) and have a tilt sensor (10) mounted on a tilt sensor mounting surface (8) defined in parallel to the ground surface. When the rotation axis (C) of the drill positioned perpendicular to the surface of the workpiece is tiled to an angle equal to or greater than a predetermined angle, the tilt sensor (10) senses the tilt shutoff a drive current of the electric drill.