Abstract: Disclosed is a reversing speed control switch. This control switch has a trigger arranged on a casing, a movable element which is moved upon operation of the trigger, a power switch for switching, on and off, a power source to be interlocked with the operation of the movable element, a reversing switch, connected to the switch, for switching the polarity of the power source, a reversing actuator whose shaft portion coupled to the reversing switch is located in the central portion the casing, and whose actuation portion is located outside the casing, and a speed control circuit for performing speed control, upon operation of the trigger. The movable element, the switch, and the speed control circuit are arranged around the shaft portion.

Abstract: A variable resistor and a printed circuit board having a velocity control circuit are separated from each other in a switch case. The resistance of the variable resistor changes upon operation of a trigger. An element constituting the variable resistor is electrically connected to a predetermined pattern of the printed circuit board through a coil spring. The heat-generating portion of a thyristor is separated from the printed circuit board. A storage component is formed in a part of the trigger shaft which is located inside the switch case. A threaded portion of an adjusting screw which extends in the shaft of the trigger, threadably engages an engaging member which can slide in the storage compartment of the trigger shaft. A movable member is brought into slidable contact with the variable resistor by the engaging member, so as to change the resistance of the variable resistor when the trigger and/or the adjusting screw is operated.

Abstract: A lock-off switch comprises a switch case, a trigger-like slider and a lock plate rockably attached to the slider and engageable therewith in a locking position so as to prevent a pulling of the trigger-like slider. A release shaft slidably penetrates into the switch case through one side thereof and is coupled to the lock plate by a coupler member. The release shaft is normally urged by a compression coil spring in such a way as to hold the lock plate in engagement with the trigger-like slider in the locked position. When the release shaft is pushed against the urging force of the compression coil spring, the coupler member moves to rock the lock plate out of the engagement with the trigger-like slider, whereby the trigger-like slider can be pulled.