SU1469491A1 - Device for reading out magnetic marks - Google Patents

Abstract

The invention relates to the field of geophysical surveys, in particular, magnetic tag reading devices for logging cables for determining depths in wells. The purpose of the invention is to improve the accuracy of reading magnetic labels at low levels of magnetization of the logging cable. The magnetic tag reader comprises a generator 1, a frequency divider 2, the first and second magnetic modulation converters.

Description

5s

cl

05

x

four

4 and 5, the first and second analog inverters 8 and 9, the first and second peak detectors Yu and 11, two switches 14 and 15, analog-to-digital converter (ADC) 16, two random-access memory (RAM) 22 and 23, switch 17, a digital comparator 24 and a logic block. When the device operates, the high accuracy of reading magnetic marks at low levels of magnetization of the logging cable is achieved due to the fact that

one

The invention relates to geophysical surveys, in particular, magnetic tag reading devices from a logging cable for determining depths in wells.

The purpose of the invention is to improve the accuracy of reading magnetic marks at low levels of magnetization of the logging cable.

Figure 1 presents the block diagram of the device; figure 2 - block diagram of the logic block; FIG. 3 shows stress and magnetic flux diagrams.

The device contains a generator 1, a divider 2 frequencies, an amplifier 3, magneto-modulation converters 4 and 5, voltage dividers 6 and 7, analog inverters 8 and 9, peak detectors 10 and 11, comparators 12 and 13, switches 14 and 15, analog-to-digital converter 16, switch 17, 3 a — sensor 18 for directional source voltage source 19, elements I 20 and 21, random access memory (RAM) 22 and 23, digital comparator 24, logic unit 25, and driver 26.

Block 25 logic form a counter 27, seven elements, and NOT 28-34, RS-trigger 35, the driver 36 and the four elements NOT 37-40.

The device works as follows.

High-frequency pulses from generator 1 are fed to the input of divider 2 frequencies. From the first output of the splitter 2 frequency pulse sequence

The analog signals at the outputs of the magneto-modulation sensors are converted by means of an ADC to a digital code, which is recorded in RAM. The value of the digital codes recorded in the RAM is directly proportional to the value of the magnetic field of the mark, independently of the magnetization value of the logging cable. The introduction of a digital comparator and a logic block makes it possible to compare these digital codes and obtain a label signal. I 3.p. f-ly, 3 ill.

(fig.Sv) through the amplifier 3 is fed to the inputs of magnetic modulators of converters 4 and 5. Magnetic modulators of 4 and 5 are set so that the distance between their centers is equal to half the width of the north pole of the mark. Depending on the direction of movement of the logging cable, which is determined by the position of the directional adjuster 18, the magnetic field of the mark will affect either the first 4 or second 5 magneto-modulation transducers. When the magnetic tag passes the first magneto-modulation transducer 4, a sequence of pulses (fig. 3) appears at its output, the amplitude of which is directly proportional to the magnetic field of the label acting on the magnetic-modulating transducer 4, and with the passage of the middle of the magnetic tag, the amplitude of the pulses (fig. W) will nait. much more. The same pulses appear on the extrude of the second magneto-modulation transducer 5 during the passage of the magnetic mark near it, only shifted in time (Fig. 3i).

At the outputs of the peak detectors 10 and 11, voltage levels appear (fig. 3k, l), the magnitude of which is directly proportional to the amplitudes of the pulses at the outputs of the magnetic modulation converters 4 and 5, the outputs of which are through dividers 6 and 7 and analog inverters.8 and 9 are connected to the inputs of peak detectors 10 and II. These levels

regularly reset by the signal from the output of the element And 2.1, generated by the shaper 26 by the signal End of the conversion (Fig.Zh) from the output of the analog-digital converter and the sequence of pulses (Fig.ze) received at the first input of the element 21 from the third output of the divider 2 frequencies. These levels from the outputs of the peak detectors 10 and 11 through the keys 14 and 15 arrive at the first input of the analog-digital converter 16 In the analog-digital converter, the conversion of the scientific research institutes at the outputs of the peak detectors 8 and 9 into the numerical code occurs, and when arriving at the first input the switch 17 and the second input of the first element AND the 20. positive pulse from the second output of the splitter 2 frequency (fig.Zd) is converted, and then written into the RAM 22, the signal from the output of the element 20 And the numerical code corresponding to the magnitude of the magnetic The ol of the label acting on the first magnetic modulating converter 4, and when the second input of the switch 17 and the second input of the second element 21 of the positive pulse of the third output of frequency divider 2 (fig. 3c) is received, the conversion occurs and then the write to the RAM 23

"

the signal from the output of the element 21 of the numerical code corresponding to the magnetic field of the label acting on the second magnetic modulating converter 5. At the same time, after writing the numerical code into the RAM 23, the peak detectors 10 and 1 are reset according to the signal from the generator 26 output. Numerical codes recorded in RAM 22 and 23 are fed to the inputs of digital comparator 24, where they are compared. If the number in the first RAM 22 is greater than the number written in the second RAM 23, then the output of the central comparator 24 is O, and if the number in the first RAM 22 is less than or equal to the number in the second RAM 23, then the output of the digital comparator is 1 The signal from the output of the digital comparator 24 is fed to the fourth input of the logic block 25.

Block 25 of logic works in the following way.

When the magnetic field of the tag does not act on the magnetic module circuits 4 and 5, at their outputs

ten

thirty

35

40

45

50

| with p 25 5

there are no high frequency pulses (fig.3z, and). Therefore, at the outputs of the comparators 12 and 13 there is O, at the outputs of the counter 27 - O, respectively, at the output of the sixth element AND-NOT 29 there is 1. Pulses coming from the first output of the splitter 2 frequency to the first input of the logic block 25, pass t- to the counting input of the counter 27 through the element IS-NOT 28. The counter 27 counts until the outputs do not have it in ts 1 and the output of the sixth element is IS-NOT 29 O. From the output of the element NOT 38 to the fourth input of the element AND- NOT 33 arrives 1..

When pulses appear, the outputs of the comparators 12 and 13 during the action of the magnetic field of the tag on a small modular converter 4 and 5 at the output of the AND-NE element 33 appear a negative pulse at the instant of the coincidence of the pulses at the second and third inputs of the element AND-NO 33 and a pulse at the first input of this: Element coming from the first output of divider 2 through the first element NOT 37. RS-flip-flop 35 switches to the state of one (fig.3m), and to the third input of the element IS-NOT 34 enters 1. When 1 arrives at the first input of the item NAND 34 from the output of digits ovogo comparator 24 at n jvtoroy input with the output of the inverter 26 through 40 at the output of AND-NO element 34 is a pulse. (fig.Zn) corresponding to the middle imagnitnoy tags. At the same time, the counter 27 is installed in O via the second input of the installation into O via the NOT 36 element and through the first input of the installation into O via the AND-NE elements 30-32 until the magnetic field of the mark on the magnetic modulation converters 4 and 5 and at the outputs comparators 12 and 13 will not disappear pulses of positive polarity. Upon termination of the zero pulse at the output of the NAND 34 element, the RS flip-flop 39 is set to O via the S input by a negative pulse generated by the driver 36.

When changing the direction of movement of the logging cable, determined by the direction adjuster 18, the number corresponding to the magnetic field value of the mark acting on the first

magneto-modulation transducer

4, is written to the second RAM 23, and the number corresponding to the magnetic field of the label acting on the second magnetic modulation converter 5 is written to the first RAM 22. The rest of the proposed device works similarly to the known one.

Claims (2)

1. A magnetic tag reader comprising a generator connected to a frequency divider, the first 15 the output of which is connected via an amplifier to the inputs of the first and second magnetic modulation transducers, the direction adjuster, the first and second comparators, the first 2o element, and the driver, characterized in that, in order to improve the accuracy of reading magnetic marks at. small magnetization levels of the logging cable, it is equipped with 25 first and second, voltage dividers, first and second analog inverters, first and second peak detectors, first and second keys, analog-digital converter, first and second - memory devices, a source of odor voltage, a switch, a second AND element, a digital comparator and a logic unit, the first input of the logic unit being connected to the first output of the frequency divider, the outputs of the first and second magnetic modulation switches. photoelectret through the first and second voltage dividers, Q analog first and second inverters connected to the inputs of the first and second comparators and to the first inputs of the first and second peak detectors, the outputs of which through the first and second keys connected minutes; the first input of the analog-digital converter, and the outputs of the first and second comparators are connected to the second and third inputs of the logic block, the control inputs gQ of the first and second keys are connected to the first and second outputs of the switch, the third and fourth inputs which are connected to the outputs the control knob direction, and the first and second g, - inputs, respectively - to the second and third outputs of the frequency divider, which are respectively connected to the first inputs of the first and second ELEZ: five o 5 o Q th gQ g, - E: And the second inputs of which are connected to the output of the conversion of the analog-digital converter, the second and third inputs of which are connected to the fourth and fifth outputs of the frequency divider, and the fifth input - to the output of the reference voltage, the data outputs of the analog-digital converter connected to the corresponding data inputs of the first and second random access memory devices, and the outputs of the latter are connected to the corresponding inputs of the digital comparator, the output of which is connected to the fourth input of the logic block, five whose input is connected to the output of the imager, which is also connected to the second inputs of pico-vik detectors, and the input of the imager is connected to the output of the second And element, which is connected to the recording input of the second random access memory, the recording input of the first random access memory -, is keyed to the output of the first element AND, 2. The device according to Clause G., characterized in that the logic block contains a counter, an RS flip-flop, a driver, four NOT elements and seven I-BE elements, the counting counter input being connected to the output of the fourth AND-NOT element, and the outputs to the inputs of the common element IS-NOT, the output of which is connected to the first inputs of the first, second and fourth elements of the IS-NOT and to the input of the second element NOT, the output of which is connected to the fourth input of the fifth element AND-NOT, the first input of which is through the first element NOT connected to the first input of the logic block, which is connected to the second th input of the fourth element AND-NOT, the second and third inputs of the fifth element AND-NOT connected to the second and third inputs of the logic block, which are connected respectively to the second inputs of the first and second elements AND-NOT, the outputs of which are connected to the first and second the inputs of the third NAND element, the output of which is connected to the first input of the installation in O of the counter, the second input of the installation to O of which is NOT connected via the fourth element to the output of the logic unit connected to the output of the seventh NAND element and through the driver to the S input RS-flip-flop, R- stroke RS-flip-flop connected to the output of the fifth NAND and the output 1D69491 RS flip-flop - to the third input of the seventh NAND element, the first input of which is connected to the fourth input FIG. 2 eight logic block, and the second input of the seventh element H-NOT through the third element NOT to the n input of the logic block. Editor A. Ogar Compiled by A.M. gkov Tehred L. Serdyukova Order 1359/54 Circulation 483 VNSHSHI of the State Committee for Inventions and Discoveries at the State Committee on Science and Technology of the USSR 4/5, Moscow, Zh-35, Raushsk nab. 113035 Production and Publishing Combine Patent, Uzhgorod, st. Gagarin, 101 Proofreader L. Pilipenko Subscription