Abstract: An acoustic therapy apparatus has a source of therapeutic acoustic waves and an ultrasound locating means with an ultrasound transducer, wherein the source and the ultrasound transducer are combined to form an oblong applicator with a longitudinal axis provided for introduction into the body interior of a patient, the ultrasound locating system generating ultrasound images with respect to a plane that contains the longitudinal axis of the applicator. The source and the ultrasound transducer are disposed relative to each other in the applicator so that the source and the ultrasound transducer are successively arranged in the direction of the longitudinal axis, with the ultrasound transducer being arranged preceding the source the in introduction direction, and the center axis of the plane describing an angle of less than 90° with that section of the longitudinal axis of the applicator located in the region of the source so that the center axis is inclined toward the source.

Abstract: In an ultrasound therapy apparatus and a method for the operation of an ultrasound therapy apparatus, a high-frequency generator generates electrical signals with different discrete frequency values that lie within a first frequency band in chronological succession. Whole multiples of the discrete frequency values do not lie in a second frequency band that corresponds to the reception band of a simultaneously operated diagnostic magnetic resonance apparatus.

Abstract: The invention is directed to a therapy apparatus for treatment with focussed ultrasound, comprising a cooled ultrasound source (1) implemented as phased array and a preceding acoustic lens (6). The ultrasound source (1) also comprises a base plate (3) arranged between the lens (6) and the ultrasound source (1) on whose side facing away from the lens (6) the ultrasound transducer elements (2.sub.1 through 2.sub.6) of the phased array are attached, whereby the base plate (3) is composed of a material with good thermal conductivity, whereby an ultrasound-conductive coolant that adjoins that side of the base plate (3) facing toward the lens (6) is situated between the lens (6) and the ultrasound source (1), whereby the base plate (3), at least in the region of the ultrasound transducer elements (2.sub.1 through 2.sub.6), comprises a thickness that is equal to an odd-numbered multiple of a quarter of the wavelength of the ultrasound in the material of the base plate (3).

Abstract: An apparatus for treating a subject with focused ultrasound waves has an ultrasound transducer composed of a number of ultrasound transducer elements. Each ultrasound transducer element has a memory connected thereto in which, during operation, a bit pattern corresponding to a desired position of the focus of the ultrasound waves is stored. A control unit cyclically addresses the individual memories in parallel such that electrical signals offset in time relative to one another according to the desired position of the focus are present at the respective data outputs of the memories, and these signals are supplied to the respective ultrasound transducer elements connected to the data outputs of the memories.

Abstract: In an ultrasound transducer arrangement having an electroacoustic transducer part, at least one acoustic matching layer is allocated to the transducer part. The acoustic matching layer is composed of an electrically conductive skeleton having interspaces connected to one another. The skeleton is constructed of particles connected to one another. The size of the particles is smaller than the wavelength of an acoustic wave in a matching layer, as a result of which no significant scattering of the wave occurs in the matching layer. The interspaces are filled with a curable casting compound.

Abstract: An apparatus for generating focused shockwaves, suitable for extracorporeal lithotripsy, has a substantially hollow-cylindrical membrane consisting of electrically conductive material and an electrical coil arrangement disposed inside the membrane which can be supplied with a high voltage pulse to rapidly repel the membrane and thereby generate a shockwave. The apparatus includes a concave reflector in the form of a paraboloid of revolution, which surrounds the membrane and coil, and which has a center axis substantially coincident with the center axis of the membrane. An acoustic propagation medium fills at least the volume between the membrane and the reflector. The shockwave generated by the cylindrical coil and membrane arrangement is reflected and focused by the paraboloid of revolution so that the shockwaves converge at a focus. The apparatus is arranged so that the focus conicides with a region of a patient to be treated with shockwave therapy, such as a calculus.

Abstract: An extracorporeal lithotripsy apparatus for treating a calculus in the body of a patient has a shock wave source which generates shock waves converging in a focus zone, and an ultrasound locating system having a sector applicator with which at least the focus zone can be scanned. The sector applicator includes a number of ultrasound transducers, so that a number of layers, proceeding parallel to each other, can be quasi-simultaneously scanned. The number of layers which can be scanned corresponds to the number of ultrasound transducers. The layers are directly adjacent each other so that displacement of a calculus in the body during treatment in a direction transverse to the acoustic axes of the scanned sectors can be observed.

Abstract: An apparatus for extracorporeal lithotripsy includes a shock wave source which generates shock waves converging in focus a zone, within which a calculus to be disintegrated is disposed. The shock wave source can be selectively driven to generate high-intensity shock waves for disintegrating the calculus, and for generating low-intensity shock waves for imaging purposes. A pressure sensor is disposed between the focus zone and the shock wave source to register the reflections of the low-intensity shock waves. The pressure sensor has a sensor surface which is substantially coextensive with the cross-sectional area of the shock waves in the region of the pressure sensor, and is connected to a reception circuit which constructs an image of the calculus during the course of treatment based on the signals from the pressure sensor.

Abstract: An extracorporeal lithotripsy apparatus includes a shock waves source which generates shock wave along an acoustic axis in a propagation direction, with the shock waves being caused to converge, either by a curvature of the shock wave source or by the use of a separate focusing element, at a focus region, the lithotripsy apparatus being initially positioned so that a calculus to be disintegrated is coincident with the focus region. During treatment, the calculus may be displaced from its original, identified position by patient movement, such as due to respiration.

Abstract: An apparatus for extracorporeal lithotripsy has one or more shock wave sources for generating shock waves converging at a focus zone in which a calculus to be disintegrated is located in a patient, and additionally has a therapeutic ultrasound source for generating ultrasound waves focused at a focus zone substantially coinciding with the focus zone of the shock wave source. The ultrasound waves generated by the therapeutic ultrasound source have a sufficiently high energy to be effective for assiting in disintegrating the calculus, as contrasted with ultrasound waves used to obtain an ultrasound image. The shock wave source and the therapeutic ultrasound source can be driven from a generator stage connected both sources, which is capable of driving the sources simultaneously or in selected chronological succession, such as in alternation.

Abstract: An ultrasound apparatus has a transducer array which includes a number of individual transducer, each transducer having a channel exclusively associated therewith. In an input stage for the ultrasound apparatus, an analog stage is provided in each channel to which the echo signals for a transducer associated with that channel are supplied. This analog stage concludes with an analog-to-digital converter in each channel. The output of the analog-to-digital converter is connected to a further processing circuit in each channel for the acquisition of Doppler signals of moving target echoes. A combined ultrasound imaging device and Doppler device is thus achieved, which allows the acquisition of Doppler signals with the digital input technology of the ultrasound imaging processing circuit. This permits expansion of digital operating RF input components of imaging devices to include Doppler signal processing.

Abstract: A shockwave source of the type wherein a shockwave is generated by rapid electromagnetic repulsion of a membrane by a rapidly energized coil has a central opening extending through the membrane and the coil. An ultrasound head of an ultrasound transmission and reception system is received in the opening. The ultrasound head is disposed in a mount which is rotatable around its longitudinal axis by a rotary drive. In one embodiment of the shockwave source, the shockwave source also has a focusing device disposed in front of the membrane, and in this embodiment the focusing device also has a central opening in which the ultrasound head is received. The ultrasound head has a distal end in contact with a liquid coupling agent for promoting transmission to, and reception from, a patient to which the shockwave source is coupled. The shockwave source is particularly suited for lithotripsy treatment of gallstones.

Abstract: A lithotripter for disintegrating a calculus in the body of a patient has a shock wave source which generates shock wave pulses which are focussed into coincidence with the calculus by an acoustic lens. The lithotripter has an ultrasound locating system integrated therewith, the locating system having a mechanically pivotable element for undertaking a sector scan of a portion of the patient to identify the position of the calculus therein. The pivotable element may be an ultrasound transducer, or may be an acoustic mirror which reflects ultrasound signals from a transducer disposed laterally of the mirror, as well as reflecting echo signals from the calculus back to the transducer. The rotational axis of the pivotable element is disposed perpendicularly on the central axis of the acoustic lens.

Abstract: A lithotripter for disintegrating a calculus in the body of a patient has a shock wave source which emits shock wave pulses which are focussed to the calculus by an acoustic lens. As seen in the propagation direction of the shock wave pulses, a semi-transmissive acoustic mirror is disposed in front of the acoustic lens at a fixed angle. An ultrasound transducer, which is part of an ultrasound locating system, such as an ultrasound sector scanner, is disposed laterally with respect to the acoustic mirror, so that ultrasound waves are transmitted by the transducer to the calculus, and the reflected waves are transmitted from the calculus to the transducer, reflected by the acoustic mirror. Shock wave pulses from the shock wave source are only minimally impeded by the mirror, so that the therapy is substantially uninfluenced by the presence of the mirror.

Abstract: A measuring cassette for checking magnetic head insertion distance and tape guide height in a magnetic tape cassette machine. A spring tongue in the cassette has at least one strain gauge on its surface to measure tongue bending, and is arranged to be deflected by insertion of the head into the cassette so as to sense the head surface or tape guide alignment with respect to the cassette.

Abstract: A diesel internal combustion engine in which during the starting and partial load operation, a number of the cylinders are operated as compressor cylinders and a number as engine cylinders. The supplied charging air of one compressor cylinder (26) is used as actuating medium for the valves (35 to 42) which are to be controlled corresponding to the operating condition of the internal combustion engine, in the connecting lines (27 to 34) between the compressor cylinders (19 to 26) and the engine cylinders (11 to 18) in the absence of a compressed air network. As a result thereof, auxiliary energy of the internal combustion engine (10) is needed only for the initiating control and a rapid shifting of the operating conditions is attained with minimum expenditures.

Abstract: A torque-measuring test cassette having at least one annular member arranged to engage a winding mandrel of a tape cassette apparatus. A resilient metal strip extending radially from each annular member has a far end arranged to be guided in a slot in the test cassette housing, so that a strip can bend as a result of torque imparted to the annular member by a winding mandrel. Each strip has a strain gauge attached to at least one side to permit remote electrical measurement of bending of the strip and thus the torque exerted by the mandrel.

Abstract: A helical scan recording and playback apparatus wherein magnetic video tape forms a helix about the peripheral surfaces of two coaxial drums which define an annular gap for magnetic heads which orbit in a chamber between the drums and engage inclined tracks at the inner side of the helix. The heads are mounted on a disk which is rotatable on a sleeve surrounding with clearance a shaft for the drums and having an internal protuberance which is tiltable with respect to the periphery of the shaft by a rod extending through an opening in the flange of one of the drums. The inclination of the plane of orbital movement of the heads relative to the central symmetry plane of the gap is changed when the speed of lengthwise movement of tape during playback deviates from the speed of lengthwise movement of tape during recording.