Abstract: A trigger switch for hand-held electric power tools in which an actuating arm for actuating a switch mechanism is pivotally supported in a case by way of a pivot shaft pivotally supported by a pair of parallel lateral walls defining the case, and a trigger member having a front end and a pair of lateral flanges is pivotally supported by the case in a coaxial relationship with the pivot shaft by way of the lateral flanges. By securely coupling an extension of the pivot shaft with one of the flanges, the switch mechanism internally accommodated in the case can be actuated by operating the trigger member. Since the switch mechanism is internally accommodated in the case, a considerable saving of space can be accomplished. Since the coupling between the pivot shaft and the trigger member can be accomplished by the extension of the pivot shaft passed through the case by way of a round opening provided in the case, sealing of the switch mechanism can be easily accomplished.

Abstract: A variable speed control switch for an electric tool including a DC motor having an armature circuit, includes: a device for turning off and on the armature circuit; an upper heat dissipation cover for covering the top of the turning off and on device; a lower heat dissipation cover for covering the bottom of the turning off and on device; a printed circuit board located at the lower surface of the lower cover for controlling motor speed; a resistor element is provided on the lower surface of the board; a movable contact assembly, including a first contact member for short circuiting the motor terminals, a second contact member for turning ON the power source, a third contact member for short circuiting the turning off and on device, and a brush for providing variable resistance by sliding over the resistor element; a device for biasing the movable contact assembly to the position of short-circuiting the motor terminals; a box like casing which receives the above-mentioned components, the power source termina