Abstract: A motor-operated hand-held device (1), such as a drilling device, has a rotary spindle 6 located in and projecting out of a housing (2). Rotational movement of a driving motor (8) is transmitted to a tool (7) situated in an end of the rotary spindle (6). A safety device (11) within the housing (2) prevents deflection of the housing about an axis (A) of the rotary spindle (6) in the event the tool (7) becomes suddenly jammed. The safety device (11) can be activated by a detection device (12) if the tool becomes jammed. The safety device (11) is located inside the housing 2 adjacent to the rotary spindle (6) and is formed of at least two component parts which cooperate in frictional engagement in the event the device is activated. One of the component parts is connected to the housing (2) and the other is connected to the rotary spindle (6).

Abstract: A motor-operated hand-held device (1), such as a drilling device, has a rotary spindle (6) located within and projecting out of a housing (2). Rotational movement of a driving motor (8) is transmitted to a tool (7) secured to the end of the rotary spindle (6). A safety device (11) within the housing (2) prevents a deflection of the housing about an axis (A) of the rotary spindle (6) in the event the tool (7) becomes suddenly jammed. The safety device (11) can be activated by a detection device (12) if the tool (7) becomes jammed. An overload slip clutch (10) is provided in the drive (9) between the driving motor (8) and the rotary spindle (6). The safety device (11) is arranged in series with the overload slip clutch (10) and is located in the drive (9) adjacent the overload slip clutch (10). When activated, the safety device (11) couples the housing (2) with the drive (9) for the rotary spindle so that the housing (2) and the drive (9) are fixed with respect to rotation relative to one another.

Abstract: A device for transmitting impulse-like blows to a continuously rotatable tool bit (6) is formed as an axially extending adapter (1) having a first chuck for the tool bit (6) and being insertable at a trailing end into a second tool bit chuck in a manually operated tool equipped with a striking mechanism. The adapter (1) has a housing (2) containing a unit for superimposing a second blow component on the first impulse blow component produced by the striking mechanism, so that an impulse-like drilling blow can be transmitted to the drill bit (6) made up of an axially directed blow component and a torsional blow component.

Abstract: A manually operable tool, such as a hammer drill, for drilling and/or removing material in at least one of brittle material and low ductile material, has a continuously rotatable chuck (8) and a motor driven striking mechanism (1) for transmitting impulse-like blows to a tool bit (9) held in the chuck (8). The tool includes members (5) for transmitting impulse-like blows composed of superimposed axially-directed blows and torsional blows to the tool bit (9) in the chuck for forming drilling blows. Further, an adaptor can be provided for attachment to the hammer drill containing the members (5) for affording the superimposed blows.

Abstract: A manual tool for removing material from brittle and/or non-ductile stock includes a housing (1) with a drive unit (2) for a tool bit (3) located within the housing (1). The tool bit is arranged to be rotated by the drive unit (3) about the bit axis. In addition, an electro-acoustic converter (4) for producing ultrasonic vibrations and a vibration amplifier (5) are positioned within the housing for superimposing ultrasonic vibrations on the rotational action of the tool bit during operation on the manual tool.

Abstract: A rock drill has an axially elongated shank (1) with a hard metal drill head (2) secured at one end. The transverse cross-section of the drill head is basically rectangular with cutters located along each of two diagonals of its cross-section. The cutters remove drillings from rock. The cutters include a main cutter (4) and two auxiliary cutters (5, 6) having the same rotational envelope curve.

Abstract: A hollow crown drill has a set of cutting members (2, 3, 4) positioned on the leading or cutting end of an annular axially extending carrier member (1). The radial width of the cutting faces (2a, 3a, 4a) of the cutting members (2, 3, 4) increases opposite to the rotational direction (D) of the carrier member (1). In addition, the cutting members (3, 4) in the set disposed counter to the rotational direction (D) are offset in the direction parallel to the axis of the carrier member relative to the cutting member of the set leading in the rotational direction. This dimensional feature relates to the increase in the size of the cutting faces (2a, 3a, 4a). With the cutting faces (2a, 3a, 4a) dimensioned as above, each of the cutting members penetrates deep into the material being drilled, so that if the usual contact pressure forces are applied abrasive wear resulting in premature failure of the hollow crown drill does not occur.

Abstract: A tool bit for machining a hard material includes a carrier member (1) supporting polycrystalline diamond platelets (2) with the platelets including a hard metal base member (2a) and a diamond-type layer (2b) supported by the base body. At least the diamond-type layer (2b) is covered by a hard metal layer (3). The hard metal layer (3) serves a carbon diffusion block, whereby the tool bit can be used for machining ferroalloys. Without such a hard metal layer (3) chemical wear occurs due to carbon interaction.

Abstract: A drilling and chiseling bit includes a base member (1) having an axis extending in the drilling and chiseling direction. The base member has an end face disposed transversely of the axis, with a recess (3) extending in the axially direction inwardly from the end face. A cutting member (2) is secured in the recess by a soldered joint. At least one of the base member and cutting member is formed to prevent the development of shear stress peaks in the end regions of the recess extending transversely of the axial direction. To prevent the shear stress peaks, relief notches or recesses can be provided in the base member (1) or the soldered joint (4) can have a variable thickness in the axial direction increasing towards the opposite ends of the recess.

Abstract: Precipitation hardenable solders are used for securing hard metal or hard material parts to the support member of a tool for drilling, chipping or cutting rock or hard construction materials. The support member is formed of steel. The hard metal or hard material parts are secured to the support member by soldering using a precipitation hardenable solder. The parts secured to the support member are subjected after a solution treatment to the tempering and precipitation hardening temperature.