Actuator for the release of an automatic emergency brake of a hand-operated powered tool

Abstract

Actuator for the release of automatic emergency brakes of hand-operated, powered tools, such as chain saws, having a driving shaft for the tool. Such emergency brakes are constituted of a brake mechanism released by means of stored energy. The actuator is constituted of a rotatable and balanced body with a small amount of friction on a shaft situated essentially parallel to the driving shaft. The actuator is fabricated of a permeable material, and has a mass having an essential inertia against rotation on the shaft. The actuator cooperates firstly with a magnet retaining the actuator with a predetermined magnetic force against rotation in an angular position of the actuator, and then with a sensor which is so arranged that an impulse for releasing the brake mechanism is given as soon as the actuator comes out of said angular position.

Dependencies are inferred from the claim text.