SU718866A1 - Method of measuring deformation of moving record carrier tape - Google Patents

Description

one

The invention relates to the field of measurement technology, in particular, to methods for measuring the longitudinal deformation of an information recording medium of an electrostatic tape, a medium in vibration measuring laboratories and research institutes.

A known method for measuring the deformation of a moving magnetic recording medium, in which the formation of a primary magnetic sigialogram is carried out, the successive rewriting of this waveform on a moving medium, the frequency demodulation of the reproduced signal 1.

However, this method does not provide the required accuracy.

The closest to the technical essence of the invention is a method for measuring the deformation of a moving tape recording medium, in which a recorded soundtrack is recorded on a fixed carrier in the form of parallel straight lines spaced at equal distance from one another, reproduced at two fixed points along each examined for the deformation of the longitudinal tracks of the tape carrier, and the deformation is judged by the difference in the moments of reproduction of the adjacent lines of the waveform 2.

The purpose of the invention is to improve the measurement accuracy.

The goal is achieved by the fact that according to the proposed method, the control

the waveform is recorded across the carrier in the form of equipotential lines spaced from one another by a distance equal to the distance between the two reproduction points.

The proposed method is implemented using two devices. One of them is intended for applying an accurate primary waveform, the other is non-means for measuring the deformation (block diagram

This device is shown in FIG. one); in fig. Figure 2 shows the arrangement of the reproducing electrodes relative to the carrier tape.

Reproducing systems 1 and 2 of the electrodes are installed perpendicular to the electrostatic carrier tape 3 with a fixed gap. The distances between reproducing systems of electrodes 1 and 2 are chosen equal to the distance between

two adjacent marks 4. On the opposite side of the cad-electrode of systems 1 and 2, there is a rigidly mounted counter-electrode of the systems of coitrodes 5 and 6, which is grounded through a resistor (in Fig. 1, groups of resistors are marked with ends 7, 8). The counter electrodes corresponding to the same electrodes in systems 1 and 2 are connected via amplifiers 9 and 10 to separate inputs of flip-flops 11. The outputs of the latter are connected via time meters 12 to the inputs of recorders 13. The reproducing electrodes of systems 1 and 2 are connected to the outputs of high-voltage source 14 wives The tape carrier 3 is rewound from the supply cassette 15 to the receiving cassette 16 by means of the actuator 17.

Measurement of the deformation of the moving tape carrier is carried out as follows.

At the moment when the electrostatic carrier tape 3 passes by the electrodes of systems 1 and 2, the high voltage across the electrodes penetrates the air gap. As a result, the charge is transferred from the electrodes of systems 1 and 2 to the surface of the carrier 3. At this moment, a short pulse is formed, the amplitude of which is proportional to the potential difference between the electrodes and the carrier section, and if the charge is transferred to uncharged parts of the carrier tape 3, then resistors 7 and 8 take the voltage drop with and. When the charge is transferred in the area of the marks 4, the amount of the transferred charge is proportional to the potential difference between the electrodes of systems 1 or 2 and the potential of the marks 4 of the signal pattern. The current flowing through the same circuit generates a voltage drop with a level U. The pulse duration with a level U is equal to the time t the carrier travels 3 ways equal to the width of mark 4. After passing the mark on a resistor 7 or 8, a voltage drop with level U occurs.

In the case of deformation of the carrier, the leading edge of the pulse of the electrode 2 will lag behind the leading edge of the electrode 1 by

a time directly proportional to the amount of deformation of the carrier tape.

The electrodes 1 and 2 in the transverse direction of movement of the carrier 3 are displaced by an insignificant distance for continuous measurement of deformation, since the information is erased by reproducing, and for a continuous measurement process, each label must be reproduced on the background.

The proposed method significantly improves the accuracy of the measurement of the longitudinal deformation of the carrier, since the measurement of the deformation is performed by purely linear physical processes, namely, the deformation is judged directly from the difference in the reproduction times of two adjacent L-layers.

Claims (2)

Invention Formula A method for measuring the deformation of a moving tape recording medium, in which a control signal is recorded on a fixed carrier in the form of parallel straight lines located on equal distance from each other, reproduced at two fixed points along each of the longitudinal tracks of the tape carrier examined for deformation, and deformation is judged by the difference in moments reproduction of adjacent lines of the waveform, characterized in that, in order to increase the measurement accuracy, the control signal is recorded across the carrier in the form of equipotential lines spaced from one another by a distance equal to the distance between the two playback points. Sources of information taken into account at the examination 1- USSR Author's Certificate No. 368469, cl. G 01B 7/00, 1971. 2. USSR author's certificate in application number 2446873, cl. G 11B 27/10, 1976 (prototype).