MOTORISCH BETRIEBENES HANDGERAET.

摘要

When using a hand held power tool, such as a hammer drill, there is a risk of the tool being wrenched out of the operator's hand if the drill bit is suddenly stopped due to the bit striking an obstacle. This risk is reduced by mounting a cylindrical mass (14) on the driving shaft (5). The mass (14) is free to rotate relative to the shaft (5) and is attached to one end of a torsion spring (16). This torsion spring is coiled around the shaft (5) and has its other end attached to the tool housing. When the shaft (5) is suddenly stopped the inertia of the mass (14) coils the torsion spring tightly around the shaft so that the spring acts as a brake and prevents the housing from rotating.