Abstract: A striking mechanism includes a working space whose first section is surrounded by a first electromagnet and whose second section is surrounded by a second electromagnet; a striking element that can move along a striking axis inside the working space and that has a magnetizable material; an anvil whose striking surface delimits the working space in the striking direction and which protrudes into the first magnetic coil and which is made of a magnetically soft material. A spring element is provided which exerts a force onto the striking element in every position in the working space in the direction of the anvil.

Abstract: A striking mechanism includes a working space whose first section is surrounded by a first electromagnet and whose second section is surrounded by a second electromagnet; a striking element that can move along a striking axis inside the working space and that has a magnetizable material; an anvil whose striking surface delimits the working space in the striking direction and which protrudes into the first magnetic coil and which is made of a magnetically soft material. A spring element is provided which exerts a force onto the striking element in every position in the working space in the direction of the anvil.

Abstract: A concrete drill for a rotary and percussively driven hand tool machine with a cutting part (1) and a striking part (2) that is axially and limited displaceable relative to the cutting part (1). Each of the cutting part (1) and the striking part (2) have a respective facial surface work area for machining a bore hole surface. The respective facial surface work area of the cutting part (1) and the striking part (2) radially overlap upon rotation of the concrete drill.

Abstract: A hand-held power tool includes a motor (6) for applying a drive torque (MA) to the drive spindle (10) of the power tool, a working tool spindle (14) for driving a tool bit (18) in a rotational direction (D) and connectable with the drive spindle (10), an angular torque generator (12) for applying an angular torque pulse to the working tool spindle (14) when a resistance torque (MB) acting on the working tool spindle (10) reaches a predetermined threshold, and a braking force generator (20) arranged on the working tool spindle (14) for applying thereto a braking force in a direction opposite the rotational direction of the working tool spindle.

Abstract: An electrical hand-held power tool for at least partially percussive driving of a tool (1) along a striking axis (A) and including a striking mechanism (2) having a striker (3) for generating striking forces on the anterior arranged tool (1) and a housing (5) enclosing the striking mechanism (2) and having a handle (6) affixed thereto, with the striker (3) being formed as a high-energy piezo actor connected with a voltage pulse generating unit (7), and rearwardly affixed to the housing (5).

Abstract: An electrical hand-held power tool for at least partially percussive driving of a tool (1) along a striking axis (A) and including a striking mechanism (2) having striking means (3) for generating striking forces on the anterior arranged tool (1) and a housing (5) enclosing the striking mechanism (2) and having a handle (6) affixed thereto, with the striking means (3) being formed as a high-energy piezo actor connected with a voltage pulse generating unit (7), and rearwardly affixed to the housing (5).

Abstract: A pneumatic percussive mechanism having an axially reciprocating percussive loaded percussion piston (2), wherein a non-contacting magnetic field sensitive sensor (3) is arranged radial thereto. The percussion piston (2) features at least externally ferromagnetic material and has a plurality of axially separated zones (4) of different magnetic permeability.

Abstract: A concrete drill for a rotary and percussively driven hand tool machine with a cutting part (1) and a striking part (2) that is axially and limited displaceable relative to the cutting part (1). Each of the cutting part (1) and the striking part (2) have a respective facial surface work area for machining a bore hole surface. The respective facial surface work area of the cutting part (1) and the striking part (2) radially overlap upon rotation of the concrete drill.

Abstract: A pneumatic percussive mechanism having an axially reciprocating percussive loaded percussion piston (2), wherein a non-contacting magnetic field sensitive sensor (3) is arranged radial thereto. The percussion piston (2) features at least externally ferromagnetic material and has a plurality of axially separated zones (4) of different magnetic permeability.

Abstract: A percussion bores for forming borer in a stone material and including a chisel stem (2) having a prismatic cross-section and provided with a chiseling head (3) and at least one radial opening (4), a twist drill (6) extending through the cylindrical through-bore (3) of the chisel stem and projecting beyond the chiseling head (7), a drilling head (10) with cutting elements (9) provided at the projecting end of the twist drill and a shank (12) provided at another end of the twist drill, and a stop (13) provided between the shank (12) and the chisel stem (2), with a drill stem being offset radially inwardly with respect to an outer diameter of the shank in the region of the stop.

Abstract: A working tool for use with a percussion power tool and including a cushioning elongate stem (3), and a head (4) connected with the stem (3) for joint rotation therewith and for a limited axial displacement relative thereto, with the tool head (4) being adapted, with respect to its resistance associated with its cushioning properties, to characteristics of the percussion piston (5) of the power tool and with the tool stem (3) and the tool head (4) having mutually abutting each other end surfaces (10) which form at least a partially flat contact upon abutting each other.

Abstract: A percussion bores for forming borer in a stone material and including a chisel stem (2) having a prismatic cross-section and provided with a chiseling head (3) and at least one radial opening (4), a twist drill (6) extending through the cylindrical through-bore (3) of the chisel stem and projecting beyond the chiseling head (7), a drilling head (10) with cutting elements (9) provided at the projecting end of the twist drill and a shank (12) provided at another end of the twist drill, and a stop (13) provided between the shank (12) and the chisel stem (2), with a drill stem being offset radially inwardly with respect to an outer diameter of the shank in the region of the stop.

Abstract: A working tool for use with a percussion power tool and including a cushioning elongate stem (3), and a head (4) connected with the stem (3) for joint rotation therewith and for a limited axial displacement relative thereto, with the tool head (4) being adapted, with respect to its resistance associated with its cushioning properties, to characteristics of the percussion piston (5) of the power tool and with the tool stem (3) and the tool head (4) having mutually abutting each other end surfaces (10) which form at least a partially flat contact upon abutting each other.

Abstract: A percussion blow added manually operable drilling tool, such as a hammerdrill, has a housing (2) containing an electric motor for rotating a tool bit chuck (9) about its axis, a control device (C) for controlling the rpm of the chuck (9) operated by the electric motor (3) which is activated by a switch (5) located on the exterior of the housing (2), and a percussion blow mechanism for periodically applying axially directed blows to a bit (10) secured in the chuck (9). The electric motor (3) is coupled to a device (12) for measuring the reaction torque. The control device (C) is connected to an evaluation unit (E) which is connected to the device (12) for measuring the reaction torque so that the rpm of the chuck can be regulated from maintaining the measured reaction torque at a maximum.

Abstract: A self-cutting, undercutting dowel (1) is formed of an axially extending anchor rod (2) with a head part (3) leading in a setting direction (S) of the dowel and an axially extending sleeve (5) laterally enclosing the anchor rod (2). At its end facing in the setting direction, the sleeve (5) has expansion sections (7) separated from one another by axially extending slots (6). The sleeve (5) can be driven over the head part (3) relative to the anchor rod (2) so that the expansion sections (7) flare radially outwardly. At least one of the expansion sections (7) has a tooth shape at its end facing in the setting direction forming a cutting edge (10) for cutting an undercut in a receiving material for the dowel. The cutting action is effected by rotating the sleeve (5). The cutting edge (10) is located at a side edge (11) of the expansion section (7) leading in the rotating direction (R) of the sleeve (5) and the cutting edge is inclined to an axis (A) of the sleeve at a first angle (.alpha.).

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: The present invention discloses a method and an apparatus which enables one to obtain definite non-modulo-2.pi.-dependent measurements wherein a method for the fiber-optic measurement of force, which is based upon the strain-induced birefringence of a single-mode light waveguide, provides a compensation method for the phase differences of two linear modes of the exiting light waves, which are caused by the force acting on the light waveguide and the consequent change in birefringence. In one embodiment of the method, a liquid crystal cell, the birefringence effect of which can be controlled electrically, is used as a compensation element. The maximum of an autocorrelation function, which occurs as an image, and the respective voltage at the liquid crystal cell, are evaluated as a measurement for the birefringence which is to be compensated for and, accordingly, for the effective force.

Abstract: A method and the device for fiber-optic measurement of the absolute value of the pretensioning in a highly loaded mechanical structural component part are based on the measurement of the phase displacement of a light wave caused by the strain-induced birefringence in a single-mode light waveguide 4 which is embedded between two metallic disks or washers 3a, 3b. Since the measurement results are ambiguous modulo-2.pi., serial or simultaneous measurement with two light wavelengths .lambda..sub.1, .lambda..sub.2 is used according to a first method variant of the invention. The quantity of 2.pi. periods can be unequivocally determined within a predetermined measuring range by means of comparing the two measurement results. The evaluation is preferably effected according to a quadrature or phase step method, known per se. According to second method variant, the light waveguide 4 is irradiated with polarized white light.

Abstract: In a process for the sampling of an electric signal changing over time, an electron beam (12) is deflected laterally and linearly over time and at the same time modulated in its intensity according to the instantaneous amplitude of the electric signal. The electron beam (12) generates on a fluorescent screen (14) a brightness-modulated bar of light, which is preferably sampled with a sensor (15) arranged ahead of the fluorescent screen (14) in the form of a CCD line camera having a linear array of sensor elements (15a, b, c).The read-out analog sampled values of the sensor (15) are subsequently digitized and further processed.The advantage of the process is its high broad-bandedness and resolution and the capability of being able to carry out an averaging without additional expenditure of time.

Abstract: An optoelectronic displacement sensor for the absolute measurement of displacement in the sub-micrometer range is described, which is constructed, according to an exemplary embodiment, with a light-emitting diode (L) as light source and two photodiodes (D1, D2), which are arranged in a difference circuit and which are opposite to one another, as radiation sensors. The sensing of displacement takes place by means of a diaphragm (2), which is displaceable between light source and radiation sensors and which influences the illumination received by of the photodiodes (D1, D2). For the homogenization of the illumination, special means are provided, which, according to an exemplary embodiment, consist of a correction filter (6) disposed in the beam path.