SU847367A1 - Method of measuring lateral oscillations of moving carrier tape - Google Patents

Description

one

The invention relates to a measurement technique, in particular, to methods for measuring motion parameters of information carriers of an electrostatic recording.

A known method of measuring transverse oscillations of a tape carrier, which consists of recording a control signal on a dielectric medium, reproduces it by scanning a beam of an electron-beam tube with a met-fiber-fiber screen across the width of the carrier, generates a pulse signal, by varying the parameters of which the transverse oscillations of the carrier are measured Dj.

The disadvantage of this method is the difficulty of providing identical movement conditions of the carrier during recording and reproduction.

The closest in technical essence to the present invention is a method for measuring transverse oscillations of a tape information carrier.

electrostatic recording, which includes the operation of forming and recording several pilot signals on a moving medium, simultaneously removing the recorded signals, converting them into a code, reproducing the pilot signals by scanning the beam of a cathode-ray flux tube, forming pulses, converting

10 in the code of their durations and judgments about the transverse oscillations of the carrier on the difference between the codes of the signals obtained during playback and recording of G22.

The disadvantages of this method are its relative complexity and lack of accuracy. It allows the measurement of the lateral oscillations of the media that occurred during the recording during playback.

20 In this case, it is necessary in the measurement process to eliminate the effect of perpendicular vibrations of the carrier during recording and transverse oscillations of the carrier,

l when playing. The accuracy of this method depends on the degree of exclusion of these factors.

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

This goal is achieved by the fact that according to the method, two waveforms are recorded on a moving medium, when played back by scanning a beam of a cathode ray tube with a metal fiber screen, pulses are formed and their duration is measured, while electrograms are recorded in the form of a stepped rising and falling across the potential of the electrostatic force. field, reproduced by scanning the oppositely directed rays of two electron-beam tubes, and with respect to the difference of the differences to the sum of the dB pairs formed pulses with the same amplitude trial of the magnitude of the transverse oscillations.

FIG. 1 is a block diagram of a device implementing this method; in fig. 2-5 timing charts of the device.

Electron-beam tubes 1 and 2 with metal-fiber screens are installed perpendicularly rigidly fixed counter electrodes 3 and 4 and sliding tape carrier 5 along them with control signalograms-6 and 7 recorded on it (Fig. 2 signalogram 6 - section from O to L2, signalogram 7 - section from L2 to L). The screens of tubes 1 and 2 are installed in parallel, and the screen of tube 2 is rotated by 180 °. The outputs of the high voltage source 8 are connected to the cathodes of tubes 1 and 2, the diverting systems of which are connected to two outputs of the sweep generator 9, the third output of the latter is connected to a generator of 10 clock pulses, grounded respectively through resistors 11 and 12, counter electrodes 3 and 4 through amplifiers 13 and 14 are connected to the distributors 15 and 16, the pulses, the first outputs of which are connected to the converters 17 and 18 of the time interval to the code, the second with blocks i 9 and 20 of the same designation NIN. Start input: the limit of pulse bodies 21 is connected to a generator of 10 clock pulses, and its first and second outputs are connected, respectively, to pairs of converters 17, 18 and 19, 20 of the time interval into the code. The outputs of these pairs of blocks are connected to the operational blocks 22 and 23 associated with the inputs of the recorder 24.

The method of measuring transverse vibrations of a tape carrier is carried out as follows.

The carrier 5 with recorded waveforms 1 and 6 and 7 is moved by an electrically driven tape mechanism (not shown). The screen centers of tubes 1 and 2 coincide with the centerline of the carrier 5. The control signal 6 reproduces the tube 1, the control signal 7 - the tube 2. This is done as follows: the cathodes of the tubes I and 2 from the output of the source 8 are supplied with a constant electronic backlight voltage the beam, and the deflecting systems from the generator 9, the pulses of the sweep voltage, (Fig. 3). Tube tube I skins up from the center of the screen up, and tube tube 2 - from the center of the screen monitored when scanning electron beams across the electrodes of one half of the tube screens

1 and 2, their potential reaches the breakdown voltage, the consequence of which is the transfer of charge to portions of carrier 5. The magnitude of the transferred charge is directly proportional to the potential difference between the screen electrodes of tubes 1 and 2 and portions recorded on the carrier of waveforms 6 and 7. Transferred The charge flows in the form of a current in the following circuits: carrier 5 - counter electrode 3 (4) - resistor 12 (13) - housing. The magnitude of the current flowing through these circuits, as well as the magnitude of the voltages falling on the resistors 12 and 13, depends on the magnitude of the transferred charge.

In the absence of transverse oscillations of the carrier 5, the signals, which can be detected on resistors 12 and 13, are identical in shape to the sections of the graph shown in FIG. 2, respectively, О О to L / j and from Ln to L. Only the path coordinates are the time coordinate, and instead of the length of the sections a of the carrier 5, the time Tjj, during which the electron beam of tubes 1 and

2 passes the distance a. The kind of signals taken from resistors 12 and 13 is shown in FIG. four.

In the presence of transverse oscillations of the carrier 5, the duration of the steps

modulated by the law of its transverse oscillations (Fig. 5). Moreover, if the velocity vector / q of transverse oscillations, the carrier 5 coincides with the velocity vector of the scanning beam of the beats of the tubes, then the duration of the steps will be more than C, otherwise - less. The scanning time of the beam across the width a of the band is performed at a speed V Vd + V the speed of transverse oscillations of the carriers 5 U% ilhl VU 7Z L / y 4 is characterized. In FIG. L / Beats) (5). During time Dg, carrier 5 is displaced from speed to vapichin (ii | .G O% r4i V Analysis of the formula (6) shows that the method allows measuring the smaller displacements, the greater - the number of brightness gradations in recorded waveforms. The more n, the greater the number of measurements that can be made during the beam sweep time, the higher the accuracy of determining the law of transverse vibrations of the carrier 5. In determining the transverse oscillations, the ratio (; -rconsi (7) n is known in advance therefore, formula (6) takes the form V. When scanning a beam On tubes I and 2 on the control waveform 6 and 7, pulses with durations T fii are formed on resistors 11 and 12 and amplified in amplifiers I3 and 14 and fed to the input of distributors 15 and 16 pulses, which odd pulses are sent to transducers 17 and 18 time intervals in the code, and even ones in 19 and 20. The generator signals 10 clock pulses, synchronized by the pulses of the generator 9 sweep, arrive at the distributor

21 pulses, which directs even pulses to blocks 17 and 18, odd pulses - to blocks 19 and 20. The period C of the pulse generator 10 is longer than time d, defined by the expression

 a / i 1

(9)

.G Clock pulses gate codes in pairs of converters 17, 18, and 19, 20 of the time and time code into the code, which arrive at the inputs of the operating units 22 and 23. In addition, the clock pulses prepare the specified converters for the following input pulses. Operational units 22 and 23 perform the following operations: subtract (tgi-C -, -;), add (C | 1), and de. . .. .. .. . laziness (-p} -L. The registrar records the results obtained at the output of the operating units 22 and 23. The proposed method has a number of preferences compared with the known. First, the process of measuring transverse vibrations is not affected by lateral deformation, so How control signals are applied to a moving medium in a prestressed and deformed state. Secondly, the high resolution of the electrostatic method of recording and reproducing information provides sufficient Internally, a large number of gradations of brightness, and therefore allows you to make a large number of gradations of brightness, as well as a large number of reference points of carrier movement during the scanning period of the electron beam of the tubes. It is practically possible to measure the instantaneous values of the transverse oscillations of the carrier. , reliable and has high speed and accuracy.

Invention Formula

A method of measuring transverse buoys of a moving tape carrier, in which two waveforms are recorded on a moving medium, when a beam of an electron beam tube with a metal fiber screen is reproduced by scanning a beam, pulses are measured and measured in that they are recorded in the form of measurement accuracy. step potential of electrostatic capacity increasing and decreasing across the carrier.

3

473678

They reproduce the scanning of the oppositely directed rays of two electron-beam tubes, and with respect to the difference of 5 to the sum of the durations of the pairs of formed pulses with the same amplitude, they judge the magnitude of the transverse oscillations. I

10 Sources of information

taken into account in the examination

1. USSR author's certificate number 568077, cl. G 11 B 27 / 10,07.12.75.

2. USSR author's certificate 15 No. 6561.04, cl. G 11 V 27 / 10.06.09.76 (prototype).

FIG. 2. Un

Claims (2)

Claim A method for measuring the transverse vibrations of a moving tape medium, in which two waveforms are recorded on a moving medium, when pulses are generated by scanning a beam of a cathode ray tube with a metal fiber screen, pulses are generated and their durations measured, characterized in that, in order to increase the measurement accuracy, the waveforms are recorded in the form of a step electrostatic potential increasing and decreasing across the carrier. fields, reproduce their scanning of oppositely directed rays of two cathode ray tubes, and with respect to the ratio of differences ₅ to the sum of the durations of pairs of generated pulses with the same amplitude, they judge the magnitude of the transverse vibrations. I 10 Sources of information taken into account in the examination 1. USSR copyright certificate No. 568077, cl. G and B 27/10.07.07.75. 2. USSR copyright certificate 15 No. 656104, cl. G 11 V 27 / 10.06.09.76 (prototype).