Hilti Aktiengesellschaft

Heinrich Pauli

Wolfgang Millauer

Michael Selb

Franz Hoyss

Axel Neukirchen

Gottfried Benz

A tool bit to be inserted into a tool bit chuck of a hand tool used for chiseling, drilling and/or percussion drilling has an axially extending chucking shank (A) with two locking grooves (1) closed at the ends spaced apart in the axial direction, and two rotary entrainment grooves (2) open at a free end of the shank. In addition, two rotary entrainment faces (3) are located in the areas of the locking grooves (1).

Tool bit and tool bit chuck for hand tools

Drive control for a drilling device including a universal motor is arranged so that the total available mains voltage is applied when a fraction of the motor torque, available for the full work range of the device, is reached. If a higher torque is desired, the motor torque/rotational speed curve follows the natural characteristic line until a load point is reached where current limitation occurs. Accordingly, as the motor speed decreases as the normal work range is exceeded, the operator of the drilling device is signaled concerning the load state due to the noise developed in the drilling device.

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Germering, Germany

Heinrich Pauli