阅读说明：本技术 光电式流量测井仪 (Photoelectric flow logging instrument ) 是由 赵希正 陈美英 左卿伶 于 2019-10-31 设计创作，主要内容包括：本发明涉及地质勘探技术领域,提供一种光电式流量测井仪,包括：运动部件,所述运动部件上设有透光孔；光电感应部件,包括发光部件和光敏部件,所述发光部件与所述光敏部件之间设置所述运动部件,所述运动部件运动以使所述发光部件、所述透光孔和所述光敏部件共线并导通光路；比较单元,所述比较单元连接所述光敏部件的输出端,所述比较单元输出预设结果,所述预设结果为根据所述光敏部件输出的光强信号与预设值的比较结果,所述预设结果对应流体清澈程度。本发明提供的光电式流量测井仪,利用光电转换原理,解决磁干扰问题,并且能够测得流体的清澈程度。(The invention relates to the technical field of geological exploration, and provides a photoelectric flow logging instrument, which comprises: the moving part is provided with a light hole; the photoelectric sensing part comprises a light emitting part and a photosensitive part, the moving part is arranged between the light emitting part and the photosensitive part, and the moving part moves to enable the light emitting part, the light holes and the photosensitive part to be collinear and conduct a light path; the comparison unit is connected with the output end of the photosensitive component and outputs a preset result, the preset result is a comparison result of the light intensity signal output by the photosensitive component and a preset value, and the preset result corresponds to the clarity degree of the fluid. The photoelectric flow logging instrument provided by the invention solves the problem of magnetic interference by using a photoelectric conversion principle, and can measure the clarity degree of fluid.)

1. An optoelectronic flow logging tool, comprising:

the moving part is provided with a light hole;

the photoelectric sensing part comprises a light emitting part and a photosensitive part, the moving part is arranged between the light emitting part and the photosensitive part, and the moving part moves to enable the light emitting part, the light holes and the photosensitive part to be collinear and conduct a light path;

the comparison unit is connected with the output end of the photosensitive component and outputs a preset result, the preset result is a comparison result of the light intensity signal output by the photosensitive component and a preset value, and the preset result corresponds to the clarity degree of the fluid.

2. The electro-optical flow logging instrument of claim 1, wherein the comparison unit comprises a comparator, the comparator is connected to an output end of the photosensitive component, the comparator receives an output signal of the photosensitive component, and the comparator outputs a preset result according to a comparison result of the output signal of the photosensitive component and a preset value.

3. The electro-optical flow logging tool of claim 2 wherein the plurality of comparators are connected in parallel to the output of the photosensitive member.

4. The electro-optical flow logging tool of claim 2, wherein a voltage follower is connected between the output of the photosensitive element and the comparator.

5. The optoelectronic flow logging tool of claim 1 wherein the moving member is a turbine shaft to which the blades are attached.

6. The optoelectronic flow logging instrument of claim 5, wherein a plurality of said light-transmitting holes are uniformly distributed circumferentially of said turbine shaft.

7. The optoelectronic flow logging instrument of claim 6, wherein the turbine shaft is provided with an optoelectronic encoder, and the light hole is provided on the optoelectronic encoder.

8. The optoelectronic flow logging instrument of claim 1 wherein said light emitting member emits red light having a wavelength range of 6300A⁰～7600A⁰。

9. The electro-optic flow logging tool of claim 1, further comprising a housing having a sealed region disposed therein, the light emitting member and the light sensitive member being disposed in the sealed region.

10. The tool of any one of claims 2-9, further comprising a signal processing circuit and a counter, wherein the signal processing circuit is coupled to the output of the comparator, and wherein the output of the signal processing circuit is coupled to the counter.

Technical Field

The invention relates to the technical field of geological exploration, in particular to a photoelectric flow logging instrument.

Background

In the hydrogeological exploration of a mine, water pumping wells and aquifers exposed in overflow wells are mutually supplemented through drill holes due to different water levels, so that longitudinal water flow in the drill holes is caused. The change of the speed of longitudinal water flow in the well at different depths is closely related to the number, thickness and depth of aquifers, the flow rate of each aquifer, the hydraulic state (water burst or water absorption), the permeability and the heterogeneity thereof, and the like. The working method of detecting the vertical flow velocity and the aperture change condition of underground water in a borehole by using an underground instrument is called flow logging.

In the last 80 th century, the flow logging technology was applied in mine hydrogeological exploration in China, and is firstly applied to hydrogeological logging work of a coal mine shaft inspection hole. The originally used instrument mainly follows the principle of former Soviet Union equipment and can only carry out point measurement. MDS-1 type well flow meters, SLJ-2 type well flow meters produced by Shanghai geological instruments, RM-2 type underground water flow meters produced by Wuhan investigation institute, LY-1 type well flow meters produced by Chongqing geological instruments and the like are developed by the national coal geological Bureau geophysical prospecting research institute. In the development process of the instruments, many experiments are carried out on the flow meter, such as methods for generating signals by a heat-sensitive type, an electromagnetic type, a deep water head, a neutron tracing and the like, but the performance effects of the instruments are not as stable and reliable as the signals generated by a rotating impeller and good in effect, especially in the measurement range, so that most of the instruments adopt a turbine type flow velocity sensor. Meanwhile, the function of constant-speed continuous measurement in the well is realized.

The working principle of the turbine flow velocity sensor is as follows: when the turbine rotates for one circle, the permanent magnet on the turbine passes through the reed pipe fixed on the turbine frame once, the reed pipe is conducted once under the action of magnetic force, and the purpose of measuring the flow rate is achieved by measuring the rotation frequency of the turbine.

However, the existing magnetic reed pipe turbine type flow velocity sensor also has the following defects:

1. in the drilling construction process, the iron pins generated by grinding rocks by a drilling tool in a drill hole are remained in the drill hole, when the flow logging instrument moves in the well, the iron pins can be adsorbed on the permanent magnet of the sensor, so that the rotational inertia of the impeller is changed, the measurement precision is reduced, and when the iron pins are adsorbed to a certain degree, the impeller is clamped with the reed pipe fixing frame, so that the sensor cannot normally work. Under the condition, the probe can only be lifted out of the well to clean the iron pin on the impeller and measure again, so that the measurement of one shaft inspection hole needs to be repeated for many times, and the detection precision and the working efficiency are seriously influenced.

2. When the flow logging instrument moves at a constant speed in a well, the rotation signal of the turbine can be detected no matter whether well liquid is clear or not, so that the flow logging instrument cannot detect the hole flushing quality within the full hole depth range. Because slurry generated by rock powder enters pores and cracks of an aquifer through well fluid pressure in the drilling process of the drilling hole, the drilling of flow logging needs to be carried out, the hole washing needs to be carried out before a water pumping experiment, the pores and cracks of each aquifer are ensured to be smooth, if the hole washing is not thorough, the detection precision is influenced, even a weak aquifer is leaked, and the hole washing quality is difficult to judge.

3. The original equipment, namely the underground instrument and the ground instrument, is in an analog measurement mode, the signal transmission between the underground and the ground is a parallel transmission mode, three transmission cables are needed for simultaneously measuring three parameters of flow rate, well diameter and well temperature, the ground instrument (a coal field digital logging system) is in a serial communication mode, the measurement parameters only need to be transmitted by one cable, and the original flow logging instrument cannot be compatible with the original flow logging instrument, so that the special ground instrument is needed for flow logging work in the drilling full-parameter digital logging work, and the measurement parameter data cannot directly enter a database of the coal field digital logging, so that the site construction and the data processing are very inconvenient.

Disclosure of Invention

The present invention is directed to solving at least one of the problems of the prior art. Therefore, the invention provides a photoelectric flow logging instrument which solves the problem of magnetic interference and can measure the clarity degree of fluid by using a photoelectric conversion principle.

An optoelectronic flow logging tool according to an embodiment of the first aspect of the invention comprises:

the moving part is provided with a light hole;

the photoelectric sensing part comprises a light emitting part and a photosensitive part, the moving part is arranged between the light emitting part and the photosensitive part, and the moving part moves to enable the light emitting part, the light holes and the photosensitive part to be collinear and conduct a light path; the comparison unit is connected with the output end of the photosensitive component and outputs a preset result, the preset result is a comparison result of the light intensity signal output by the photosensitive component and a preset value, and the preset result corresponds to the clarity degree of the fluid.

According to an embodiment of the present invention, the comparing unit includes a comparator connected to an output terminal of the photosensitive member, the comparator receives an output signal of the photosensitive member, and the comparator outputs a preset result according to a comparison result of the output signal of the photosensitive member with a preset value.

According to one embodiment of the present invention, the comparator is provided in plurality, and the plurality of comparators are connected in parallel to the output terminal of the photosensitive element.

According to one embodiment of the invention, a voltage follower is connected between the output of the photosensitive element and the comparator.

According to one embodiment of the invention, the moving part is a turbine shaft to which the blades are attached.

According to one embodiment of the invention, a plurality of the light-transmitting holes are uniformly distributed in the circumferential direction of the turbine shaft.

According to one embodiment of the invention, a photoelectric encoder is arranged on the turbine shaft, and the light hole is formed in the photoelectric encoder.

According to an embodiment of the present invention, the light emitting part emits red light having a wavelength range of 6300A⁰～7600A⁰。

According to an embodiment of the present invention, the light emitting device further comprises a housing, wherein a sealing region is arranged in the housing, and the light emitting component and the light sensitive component are arranged in the sealing region.

According to an embodiment of the present invention, the apparatus further comprises a signal processing circuit and a counter, wherein the signal processing circuit is connected to the output end of the comparator, and the output end of the signal processing circuit is connected to the counter.

One or more technical solutions in the embodiments of the present invention have at least one of the following technical effects: the moving part is matched with the photoelectric sensing part, the flow velocity of the fluid is measured by utilizing photoelectric conversion, the problem of magnetic interference is solved, the light emitting part adopts a red light source, when visible light is transmitted in liquid (such as water), the absorption coefficient of the red light is minimum, the attenuation of the light in the transmission process is small, the interference of the light emitting part on a detection result is reduced, and the detection accuracy is improved.

Furthermore, the photoelectric sensing component is matched with the comparison unit, the clarity degree of the fluid can be measured, the whole structure is simple, the cost is low, the using effect is good, and the device is particularly suitable for measuring the flow rate and the flow rate of the fluid in a well and obtaining the hole flushing quality.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a schematic diagram of a flow velocity sensor of an optoelectronic flow logging tool according to an embodiment of the present invention;

FIG. 2 is a schematic diagram of a well fluid detection circuit of the electro-optical flow logging tool according to an embodiment of the present invention;

FIG. 3 is a schematic diagram of a serial communication circuit of an optoelectronic flow logging tool provided by an embodiment of the present invention;

reference numerals:

1. a light emitting part; 2. a lead wire; 3. a sealing zone; 4. a photosensitive member; 5. a photoelectric encoder; 6. a blade; 7. a friction reducing member; 8. a housing; 9. a turbine shaft; 10. a voltage follower; 11. a first comparator; 12. a second comparator; 13. a third comparator; 14. a shaping width fixer; 15. an integrator; 16. a voltage/frequency converter; 17. a counter; 18. a latch; 19. a time delay; 20. a timer.

Detailed Description

The embodiments of the present invention will be described in further detail with reference to the drawings and examples. The following examples are intended to illustrate the invention but are not intended to limit the scope of the invention.

In the description of the embodiments of the present invention, it should be noted that the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience in describing the embodiments of the present invention and simplifying the description, but do not indicate or imply that the referred devices or elements must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the embodiments of the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the embodiments of the present invention, it should be noted that, unless explicitly stated or limited otherwise, the terms "connected" and "connected" are to be interpreted broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; may be directly connected or indirectly connected through an intermediate. Specific meanings of the above terms in the embodiments of the present invention can be understood in specific cases by those of ordinary skill in the art.

In embodiments of the invention, unless expressly stated or limited otherwise, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through intervening media. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of an embodiment of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.

Referring to fig. 1 to 3, an embodiment of the present invention provides an optoelectronic flow logging tool, including: the moving part is provided with a light hole; the photoelectric sensing part comprises a light emitting part 1 and a photosensitive part 4, a moving part is arranged between the light emitting part 1 and the photosensitive part 4, and the moving part moves to enable the light emitting part 1, the light holes and the photosensitive part 4 to be collinear and conduct a light path; and the comparison unit is connected with the output end of the photosensitive component and outputs a preset result, and the preset result is a comparison result of the light intensity signal output by the photosensitive component and a preset value and corresponds to the clarity degree of the fluid.

Luminous component 1 and the relatively fixed setting of light sensitive component 4, moving part moves under the exogenic action of fluid, moving part moves luminous component 1, during light trap and light sensitive component 4 collineation, the light of luminous component 1 transmission shines light sensitive component 4 through the light trap, light signal is received to light sensitive component 4, light sensitive component 4 converts received light signal into the signal of telecommunication, and obtain moving part's movement cycle according to the signal of telecommunication, the velocity of flow sensor has also been formed, can measure fluid flow rate and flow.

Meanwhile, the clarity degree of the fluid can be judged according to the light intensity signal received by the photosensitive component 4. Under the conditions that the light source intensity of the light emitting component 1 is certain and the propagation distance between the light emitting component 1 and the photosensitive component 4 is certain, the light transmission performance of a propagation medium (such as well fluid) determines the amplitude of a signal output by the photosensitive component 4, so that whether the fluid is clear or not can be judged according to the light intensity signal output by the photosensitive component 4, and whether hole washing in a well is thorough or not can be judged.

The preset value of the comparison unit is a signal corresponding to the light intensity signal output by the photosensitive component 4, and can be a light intensity signal, and a grade boundary value is preset according to requirements. When the light intensity signal output by the photosensitive element 4 is converted into an electrical signal, the preset value is the corresponding electrical signal.

It should be noted that the output end of the photosensitive component 4 outputs an approximate positive sine wave voltage or current signal, the frequency of which is proportional to the fluid flow rate to measure the flow rate, and the photoelectric sensing component and the moving component are combined to form the flow rate sensor. Specifically, the photosensitive component 4 includes a photosensitive resistor, and a fixed voltage is applied to two ends of the photosensitive resistor to obtain a varying current signal; alternatively, a fixed current may flow in the photo-resistor to obtain a varying voltage signal.

The motion form of the motion part can be various forms such as rotation, swing, linear motion and the like. When the moving member is the turbine shaft 9, the turbine shaft 9 is rotationally moved.

This embodiment adopts the photoelectric conversion principle, carries out velocity of flow, flow measurement, and overall structure is simple, with low costs, long service life receives environmental disturbance little, is applicable to the flow or the velocity of flow measurement of multiple occasion. Especially, when flow measurement in the well is carried out, the problem of ferromagnetic substance interference is solved, the measurement sensitivity is improved, the clarity degree of the fluid can be measured, and the hole washing quality is obtained, so that the hole washing is reminded in time.

The electrical signal output from the output terminal of the photosensitive element 4 may be a voltage or a current, and the voltage signal is used as an example for description hereinafter.

In one embodiment, the comparing unit comprises a comparator, the comparator is connected to the output end of the photosensitive component 4, the comparator receives the output signal of the photosensitive component 4, and the comparator outputs the preset result according to the comparison result between the output signal of the photosensitive component 4 and the preset value.

The amplitude of the approximately positive sine wave voltage or current signal output by the output end of the photosensitive component 4 is related to the intensity of light received by the photosensitive component 4, and the intensity of light is influenced by the clarity degree of the fluid, so that the clarity degree of the fluid can be obtained through the amplitude. Wherein the preset value is a voltage value, and the amplitude value output by the photosensitive component 4 is compared with the preset value.

Further, a voltage follower 10 is connected between the output end of the photosensitive component 4 and the comparator, and the voltage follower 10 plays roles of buffering and isolating, plays a role of impedance matching, and improves signal stability.

When one comparator is arranged, the result obtained by the comparator is two, namely clear or turbid, clear indicates that the quality of the hole washing meets the requirement, and turbid indicates that the quality of the hole washing does not meet the requirement. Specifically, when the output signal of the photosensitive element 4 is greater than a preset value, the preset result output by the comparator is a high level 1, which indicates that the signal is clear; when the output signal of the photosensitive element 4 is smaller than the preset value, the preset result output by the comparator is low level 0, which indicates turbidity.

In another embodiment, a plurality of comparators are provided and connected in parallel to the output end of the photosensitive component 4, and the preset values of at least two comparators are different, so that the clear or turbid fluid can be judged, and the clarity degree of the fluid can be divided into a plurality of grades.

Referring to fig. 2, three comparators (i.e., three-step voltage comparator circuit) are illustrated. The comparator includes a first comparator 11, a second comparator 12, and a third comparator 13. The preset result of the first comparator 11 is: when the output signal of the photosensitive component 4 is greater than the first preset value, the preset result output by the first comparator 11 is a high level 1, and when the output signal of the photosensitive component 4 is less than the first preset value, the preset result output by the first comparator 11 is a low level 0; similarly, the preset result of the second comparator 12 is: when the output signal of the photosensitive component 4 is greater than the second preset value, the preset result output by the second comparator 12 is a high level 1, and when the output signal of the photosensitive component 4 is less than the second preset value, the preset result output by the second comparator 12 is a low level 0; the preset result of the third comparator 13 is: when the output signal of the photosensitive element 4 is greater than the third preset value, the preset result output by the third comparator 13 is a high level 1, and when the output signal of the photosensitive element 4 is less than the third preset value, the preset result output by the third comparator 13 is a low level 0.

The first preset value, the second preset value and the third preset value are sequentially decreased. The voltage signal of the photosensitive component 4 is isolated by a voltage follower 10 with a high impedance input and then enters a third order voltage comparator circuit. Specifically, when the output value of the voltage follower 10 is greater than the first preset value, the outputs of the first comparator 11, the second comparator 12 and the third comparator 13 are 111, and at this time, the record is that the fluid is clear, and the hole washing quality is good; when the output value of the voltage follower 10 is smaller than the first preset value and larger than the second preset value, the outputs of the first comparator 11, the second comparator 12 and the third comparator 13 are 011, at this time, the record is that the fluid is not clear, and the hole washing quality is general; when the output value of the voltage follower 10 is smaller than the second preset value and larger than the third preset value, the outputs of the first comparator 11, the second comparator 12 and the third comparator 13 are 001, and at this time, the record is that the fluid is turbid, the hole washing quality is poor, and the re-hole washing can be reminded.

One example of the first preset value, the second preset value and the third preset value is shown in fig. 2, and the first preset value, the second preset value and the third preset value are 8V, 6V and 4V, respectively.

In another embodiment, shown in connection with FIG. 1, the moving part is a turbine shaft 9, and the blades 6 are attached to the turbine shaft 9. Furthermore, an antifriction piece 7 is arranged between the turbine shaft 9 and the blades 6, so that the friction resistance is reduced, and the measurement accuracy is improved. The friction reducing member 7 may be a quartz material.

In another embodiment, a plurality of light holes are uniformly distributed in the circumferential direction of the turbine shaft 9, and the turbine shaft 9 rotates for a circle to acquire signals for multiple times, so that the measurement accuracy is improved.

In another embodiment, the turbine shaft 9 is connected with a photoelectric encoder 5, the light hole is formed in the photoelectric encoder 5, and the photoelectric encoder 5 is used for measuring the rotation angle of the turbine shaft 9 and is matched with the light hole to ensure the measurement accuracy.

In another embodiment, the light emitting component 1 and the photosensitive component 4 are symmetrically arranged on two sides of the axis of the moving component, so that the distance between the light emitting component 1 and the photosensitive component 4 is reduced, the influence of light propagation loss on a measurement result is reduced, and the measurement accuracy is improved.

In another embodiment, the photoelectric flow logging instrument further comprises a housing 8, a sealing area 3 is arranged in the housing 8, and the light emitting component 1 and the photosensitive component 4 are arranged in the sealing area 3, so that the fluid is prevented from interfering with the operation of the light emitting component 1 and the photosensitive component 4, and the service lives of the light emitting component 1 and the photosensitive component 4 are ensured. The light emitting part 1 and the light sensitive part 4 in the sealing region 3 are connected to other parts through the lead wires 2.

In another embodiment, the sealing area 3 is formed by filling sealant, and has simple structure, low cost and convenient processing.

In another embodiment, the light emitting component emits red light having a wavelength range of 6300A⁰～7600A⁰When visible light is transmitted in liquid (such as water), the absorption coefficient of red light is minimum, the attenuation of light in the transmission process is small, the interference of the light-emitting component on the detection result is reduced, and the detection accuracy is improved. Specifically, the wavelength range of visible light is 7600A⁰～4000A⁰And the wavelength of red light is 7600A⁰～6300A⁰The absorption coefficient of red light in visible light sources is minimal. According to the optical principle: i0e- α d (transmission law), the attenuation of light in transmission is mainly determined by the absorption coefficient α and the transmission thickness d. When d is constant, alpha is the main parameter of choice, and by the principle of transmission, the longer the wavelength of light in water, the smaller alpha, and vice versa. To make the absorption coefficientSmall, the larger the wavelength of the light source is selected.

Specifically, the blades 6 are made of the molded polyaluminium phosphate, and have the density of 1 (close to the density of water), 4 blades 6, the inclination angle of 34 degrees and the lead of 7.8 cm. The top end of the turbine shaft 9 is provided with a photoelectric encoder 5, the diameter of the turbine shaft 9 is 8mm, the length of the turbine shaft 9 is 8mm, the photoelectric encoder 5 is provided with 4 light holes, and in order to reduce the loss of light intensity in the light path, the turbine shaft 9 and the shell 8 are made of polymethyl methacrylate. The light emitting part 1 has a wavelength of 6300A⁰～7600A⁰And the light emitting part 1 is directed toward the photoelectric encoder 5 through the light shield. Photosensitive part 4 is equipped with in 5 rear shell of photoelectric encoder 8, and when the installation, luminous component 1, photoelectric encoder 5, photosensitive part 4 collineation, when well liquid flows, and the effect of flowing power takes place to rotate for blade 6 in the well liquid, and when light trap and luminous component 1, photosensitive part 4 collineation, the light path switches on and produces a photoelectric signal, produces four signals of telecommunication when every rotates a week. And because the lead of the blade 6 is 7.8cm, namely when water flows for 7.8cm, the turbine shaft 9 rotates for a circle, and a 4Hz measuring signal can be obtained at a water flow speed of 8cm per second, and the resolution is improved by 4 times compared with the existing instrument.

In another embodiment, as shown in fig. 3, the optoelectronic flow logging tool further comprises a signal processing circuit and a counter 17, the signal processing circuit is connected to the output end of the comparator, the output end of the signal processing circuit is connected to the counter 17, and the counter 17 records the number of times of the output signal of the comparator, that is, the number of times of the light path connection, and further obtains the frequency of the moving part to measure the flow rate of the fluid. The output of each comparator is provided with a signal processing circuit and a counter 17.

Specifically, the signal processing circuit comprises a shaping width fixing device 14, an integrator 15 and a voltage/frequency converter 16 which are sequentially connected, wherein the voltage/frequency converter 16 is connected with a counter 17, the counter 17 is connected with a latch 18, a delayer 19 is connected on the counter 17, the delayer 19 is connected with a timer 20, and the timer 20 is connected with the latch 18. The voltage signal from the comparator is shaped and width-fixed by the retriggerable monostable circuit, the pulse voltage signal with fixed width is integrated by constant current (F/V), and then sent to the high-precision voltage/frequency converter 16 to obtain a stable frequency signal, and then the stable frequency signal is counted and latched in a certain counting time and sent to the eight transmission circuits. Through the processing, the measured signals are compatible with a ground instrument of the coal field digital logging system, the digital processing of the multi-channel signals and the serial communication with the ground coal field digital logging instrument are realized, and the problem that the frequency of the flow velocity measurement signals is low and direct counting cannot be realized in a rear-stage multi-channel signal time-sharing transmission circuit is solved.

Furthermore, the time sequence control of the underground transmission part is to generate 8 channel control square wave signals according to the time sequence, so that 8 paths of signals can be transmitted in a time-sharing serial mode. Each parameter signal measured by the downhole instrument can be distributed to any one of the 1-7 channels, the 8 th channel is 16 '1's as a synchronous signal, and after serial transmission is realized, a signal wire only occupies one cable core after one frame of data is transmitted for 32.768 ms.

When the embodiment is applied to a well, the photoelectric sensing technology is applied to the logging work of the hydrogeological exploration of the mine; the interference of ferromagnetic substances in the well is successfully eliminated, so that the detection precision and the working efficiency are greatly improved; the hole washing quality of the drilled hole can be accurately measured, and the problem which always troubles the flow logging work is solved; the data communication with the ground instrument of the coal field digital logging system is realized, a plurality of problems of the original analog instrument are solved, and the precision, the efficiency and the data processing function of the flow logging work are greatly improved; the structure is greatly simplified, the cost is reduced, and meanwhile, the environmental adaptability is improved and the service life is prolonged.

The above embodiments are merely illustrative of the present invention and are not to be construed as limiting the invention. Although the present invention has been described in detail with reference to the embodiments, it should be understood by those skilled in the art that various combinations, modifications or equivalents may be made to the technical solution of the present invention without departing from the spirit and scope of the technical solution of the present invention, and the technical solution of the present invention is covered by the claims of the present invention.