Distance measuring device operating with torsional ultrasonic waves detected without mode conversion

摘要

The invention relates to an ultrasonic distance measuring device for linear distance measurement comprising a tube of magnetostrictive material, a magnet displaceable relative to the tube for generating torsional ultrasonic pulses as a function of electrical pulses produced by a pulse generator and travelling along the tube, these torsional ultrasonic pulses serving as position signals, and also comprising an ultrasonic receiver coupled to the tube for converting ultrasonic pulses generated in the tube into electrical signals and a measuring circuit for ascertaining the position of the movable magent as a function of the time interval between the signals obtained from the position signals and at least one respective reference signal generated by the presence of an electrical pulse. In accordance with the invention, the ultrasonic receiver for direct detection of torsional pulses is provided as a section of the tube which is circumferentially magnetized on the basis of remanence and a coil surrounding this section in axial direction.