Abstract: A drill bit having a drill body and a drill shank including a substantially cylindrical guide portion (10) having at least one guide surface (101, 102), and a locking portion (11) projecting radially beyond the guide portion and having locking surfaces (111, 112) extending substantially perpendicular to a longitudinal axis of the drill bit, with the locking portion (11) having, perpendicular to the drill bit longitudinal axis, a non-circular cross-section; and a drill chuck for receiving the shank.

Abstract: A working tool holder for a drilling or chiseling device includes a holder sleeve with an axially extending conically shaped section within a holder opening or bore. A working tool to be secured in the holder sleeve, has a tool shaft with a conically shaped section to engage the conically shaped section in the holder opening. Grooves are formed in the tool shaft to receive inwardly projecting ridges in the holder opening. The tool shaft has recesses to receive the pins mounted in the holder sleeve. The tool shaft and an actuating sleeve extending around the holder sleeve each have connecting threads for securing the working tool in the holder.

Abstract: 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.

Abstract: A drilling stand has an axially extending guide column with a U- or C-shaped transverse cross-section forming an interior space in which a carriage is guided for movement in the axial direction. A drilling unit is mounted on the carriage and includes a drive member supported on the carriage within the interior space and a receiving part forming a holder for a drilling tool, connected to the drive member and projecting laterally outwardly from the guide column.

Abstract: A stand for a drilling tool includes a support column with a carriage movably mounted on the column. A carrier member for a drilling tool can be secured to the carriage with support sections on the carrier member in engagement with support surfaces on the carriage. One of these support surfaces is provided by the eccentric circumferential surface on an eccentric peg which is rotatably mounted in the carriage. The support section engageable with the peg has a catch projection which prevents displacement of the carrier member from the carriage when the eccentric surface on the peg is aligned opposite the corresponding support section on the carrier member. The projection extends outwardly from the support section by an amount at least equal to the eccentricity of the circumferential surface of the peg.

Abstract: On a drill stand, a drilling member is movable between an inactive position spaced from the material to be drilled and an active position in contact with the material to be drilled. A marking element is mounted on the stand and is slidably movable between a retracted position and a marking position. In the marking position, a pointer on the element can mark the drilling axis on the material to be drilled. With the drilling axis located, the drilling member can be moved into the active position to commence drilling.

Abstract: In a stator for an electromotor, field coils associated with a packet of laminations are spaced apart by filler pieces. The combination of the field coils and filler pieces form an annular arrangement. Each filler piece extends between the adjacent ends of two field coils. The filler pieces are slotted in the radial direction to provide a certain adjustability in the circumferential direction of the annular arrangement where the dimension between the adjacent ends of the field coils is subject to variation.

Abstract: In an electromotor having a stator and a rotor, a collector is located on the rotor and carbon brushes are movably supported in carbon supports relative to the outer circumferential periphery of the collector. Segment-shaped shells are located on the upstream sides of the carbon brushes and cover an angular part of the outer circumferential periphery of the collector. Downstream of the carbon brushes the outer circumferential periphery of the collector is uncovered. Accordingly, the collector can be cooled while protecting the collector and carbon brushes from contamination.