Abstract: A core bit for abrasive cutting including a cylindrical tube (3) provided at its end surface with cutting or abrasive bodies (2) and a cover (4) provided at an opposite end surface of the cylindrical tube (3) and secured thereto and having, along its central axis (A), a shank (5) to be received in a rotary power tool, with the cover (4) being dimensioned, with respect to a set excitation frequency, for forming a whole number of maximum amplitude oscillations of a concentric flexural oscillation, and the cylindrical tube (3) being dimensioned, with respect to a set excitation frequency, for forming a whole number of maximum amplitude oscillations of axial longitudinal oscillations.

Abstract: A device for operating a tool has an ultrasound adapter with an capacitive electro-acoustic transducer (4) connected to an electrical ultrasonic frequency generator (8) for producing ultrasonic wave for a tool (2) driven by the device, wherein the capacitive electro-acoustic transducer (4) is connected with a secondary winding (5) and the ultrasonic frequency generator (8) is connected with a primary winding (7) of a transformer (6).

Abstract: A core bit for abrasive cutting including a cylindrical tube (3) provided at its end surface with cutting or abrasive bodies (2) and a cover (4) provided at an opposite end surface of the cylindrical tube (3) and secured thereto and having, along its central axis (A), a shank (5) to be received in a rotary power tool, with the cover (4) being dimensioned, with respect to a set excitation frequency, for forming a whole number of maximum amplitude oscillations of a concentric flexural oscillation, and the cylindrical tube (3) being dimensioned, with respect to a set excitation frequency, for forming a whole number of maximum amplitude oscillations of axial longitudinal oscillations.

Abstract: An electrical hand-held power tool including an arrangement for actively damping vibrations applied to the tool handle (2) and arranged between the handle and the hammer mechanism module (3) with a possibility of a limited axial displacement along the percussion axis (A) with respect to the hammer mechanism module (3) and having at least one electromechanical actuator (5a, 5b) surrounded by an elastic spring (8a, 8b), a sensor for sensing vibrations acting on the handle (2), and a microprocessor (7) for dynamically controlling the actuator (5a, 5b) in accordance with the signal generated by the sensor.

Abstract: A device for operating a tool has an ultrasound adapter with an capacitive electro-acoustic transducer (4) connected to an electrical ultrasonic frequency generator (8) for producing ultrasonic wave for a tool (2) driven by the device, wherein the capacitive electro-acoustic transducer (4) is connected with a secondary winding (5) and the ultrasonic frequency generator (8) is connected with a primary winding (7) of a transformer (6).

Abstract: A method of detecting foreign bodies in a medium with a radar having a transceiver, and including emitting a radar wave through a wall surface into the medium with the transceiver, detecting a radar signal reflected in the medium, pre-processing the reflected radar signal and subjecting the pre-processed radar signal to evaluation and assessment, determining a characteristic of a foreign body at a stationary position of the transceiver with an algorithm which is based on a pre-processed, digitalized receivable signal, which characteristic permits to recognize differences between a shape of the reflected radar signal and stored comparison values, and conducting a comparison assessment of the shape differences of the reflected signal against predetermined threshold values.

Abstract: A method of determining a relative permittivity (&egr;r) of concrete including providing a radar apparatus to be positioned on a concrete mass and having a transmitting antenna (2) for emitting a radar wave into the concrete mass and a receiving antenna (3) for detecting a cross-signal generated by the radar wave emitted into the concrete mass by the transmitting antenna, electronically processing the cross-signal, and determining the relative permittivity (&egr;r) by determining, with an algorithm, a frequency-dependent amplitude shifting in a spectrum of a signal section with in a predetermined time slot (t1); and using the so determined permittivitiy for depth scaling and determining presence of foreign bodies.

Abstract: A method of determining the ability of a medium to absorb electromagnetic waves including placing antenna unit (10) having spaced transmitting and receiving antennas (2 and 3) on a limiting surface of a medium (13), emitting, with the transmitting antenna (2), a radar wave into the medium (13) which is detected as a cross-signal by the receiving antenna (3), pre-processing and digitalizing the cross-signal, and, thereafter, analyzing the cross-signal with an algorithm for determining the ability of the medium to absorb electromagnetic waves and, thereby, a type of the medium; and an electromagnetic sensor the operation of which is based on the method.