| 摘要 |
A device for adjusting the rotation speed of a drill or hammer drill as a function of the material to be worked and as a function of the drill bit diameter has a logarithmic potentiometer whose pick-off is connected to a rotating knob (2) which has markings (3) for the drill bit diameter on its circumference, in a logarithmic spacing. These markings (3) interact with reference markings (4; 4') for the materials which are to be worked, which reference markings (4; 4') are arranged on the housing of the drill, adjacent to the rotating knob (2). <IMAGE>
|
