Pulse test circuit for gamma probe

Abstract

The utility model relates to a pulse test circuit for a gamma probe. The pulse test circuit comprises a power supply module, a signal conversion module and a signal processing module, the power supply module is used for converting an alternating-current power supply into a + 5V direct-current power supply and converting the + 5V direct-current power supply into a + 3.3 V direct-current power supply; the signal conversion module is used for filtering the gamma pulse signal through a comparator and isolating the gamma pulse signal through a photoelectric coupler to generate a current pulser signal; the signal processing module is used for collecting the current pulse signal generated by the signal conversion module into the single-chip microcomputer to calculate a gamma value. A stable direct-current power source can be provided for the gamma probe, gamma pulse signals are collected while the gamma probe works normally, accumulation calculation of the gamma pulse signals is carried out, compared with a traditional gamma probe testing mode, the gamma value can be detected without a ground system, a directional probe and a PC end serving as necessary testing equipment, testing equipment is simplified, and the testing efficiency is improved. And the test operation process is simplified, and the test convenience is greatly improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of gamma probe testing, and in particular relates to a pulse testing circuit for a gamma probe. Background Art

[0002] In the exploration and development of underground resources such as oil and natural gas, gamma probes are an essential downhole instrument. Gamma probes are usually used to measure the gamma radiation intensity of the formation to assist drilling construction and find underground high-quality resources. However, in the traditional gamma probe testing method, it is necessary to connect with the directional probe, the ground system and the PC. The connection equipment is complicated and the operation steps are cumbersome, which not only increases the difficulty of the test, but also affects the convenience of the test.

[0003] The Chinese utility model patent (patent number CN202222525511.8) discloses a gamma probe test system, including a host computer, a control device and a probe environment box; the probe environment box includes: vibration and fixing tooling, a heating device and a temperature sensor; the vibration and fixing tooling includes multiple fixed channels for fixing the gamma probe; the temperature sensor and the heating device are placed in the box; the gamma probe is fixed by the vibration and fixing tooling and provides an underground vibration environment for the probe, and the heating device is used to provide an underground high temperature condition for the gamma probe. The control device is used to start counting gamma photons when receiving the test instruction sent by the host computer, and at the same time receive the temperature information collected by the temperature sensor, and send the counting information to the host computer for visual display. However, the connection equipment is complicated and the operation steps are cumbersome.

[0004] The Chinese utility model patent (CN201320753255.6) discloses a downhole measurement while drilling assembly, including a non-magnetic suspension drill collar short section, a pulse generator, a directional probe, an electromagnetic wave resistivity logging short section, and a power module. The downhole instrument also includes a gamma probe connected to the directional probe at the front end and connected to the electromagnetic wave resistivity logging short section at the rear end through a through-core centralizer. The gamma probe measures the intensity of gamma rays emitted by naturally existing radionuclides (K, U, Th, etc.) in the rock in the wellbore profile during nuclear decay to determine the lithology profile, estimate the mud content, and perform stratigraphic comparison. At the same time, after the gamma probe receives the natural radiation of the rock, it outputs the number of electrical pulses proportional to the received signal, and the number of gamma rays in the area is obtained according to the number of electrical pulses, and then a standard logging curve is drawn. As described above, it is a traditional gamma probe, which is connected to the directional probe, the ground system and the PC. Summary of the invention

[0005] The purpose of the utility model is to solve the above technical problems and provide a pulse test circuit for a gamma probe tube which can directly detect the gamma value.

[0006] To achieve the above-mentioned purpose, the utility model provides a pulse test circuit for a gamma probe, comprising a power supply module, a signal conversion module and a signal processing module; the power supply module is used to convert a 220V, 50Hz AC power supply into a +5V DC power supply, and provide a +5V DC power supply to the signal conversion module, and at the same time convert the +5V DC power supply into a +3.3V DC power supply, and provide a +3.3V DC power supply to the signal processing module; the signal conversion module is used to generate a current pulse signal after filtering the gamma pulse signal through a comparator and isolating it through a photoelectric coupler; the signal processing module is used to collect the current pulse signal generated by the signal conversion module into a single-chip microcomputer to calculate the gamma value, and send the gamma value to a display screen for display.

[0007] Furthermore, the power module includes a switching power supply, a diode D1, a tantalum capacitor C2, a tantalum capacitor C3, a capacitor C4 and a low-voltage linear regulator U5; the anode of the diode D1 is connected to the +5V DC power supply output by the switching power supply, and the cathode is connected to the Vin pin of the low-voltage linear regulator U5; the anode of the tantalum capacitor C2 is connected to the Vin pin of the low-voltage linear regulator U5, and the cathode is grounded; the anode of the tantalum capacitor C3 is connected to the Vout pin of the low-voltage linear regulator U5, and the cathode is grounded; one end of the capacitor C4 is connected to the Vout pin of the low-voltage linear regulator U5, and the other end is grounded; the GND pin of the low-voltage linear regulator U5 is grounded.

[0008] Furthermore, the signal conversion module includes a comparator U3A, a comparator U3B, an optocoupler U1 and an optocoupler U2; pin 1 of the comparator U3A is connected to pin 1 of the optocoupler U1, pin 2 of the comparator U3B is connected to pin 1 of the optocoupler U2, pin 3 of the comparator U3A is connected to a +5V DC power supply output by a switching power supply, pin 4 of the comparator U3B is connected to pin 6 of the comparator U3A, pin 5 of the comparator U3B is connected to gamma signal input port 2, pin 7 of the comparator U3A is connected to gamma signal input port 1, and pin 12 of the comparator U3A is grounded.

[0009] Furthermore, the signal processing module includes a single-chip microcomputer U4, pins 2 and 4 of the optocoupler U1 are both grounded, and pin 5 is connected to pin 11 of the single-chip microcomputer U4; pins 2 and 4 of the optocoupler U2 are both grounded, and pin 5 is connected to pin 12 of the single-chip microcomputer U4.

[0010] Furthermore, the signal conversion module also includes a resistor R1, a resistor R2, a resistor R3, a resistor R4, a resistor R5 and a resistor R6; one end of the resistor R1 is connected to the Vout pin of the low-voltage linear regulator U5, and the other end is connected to the No. 5 pin of the optocoupler U1; one end of the resistor R2 is connected to the Vout pin of the low-voltage linear regulator U5, and the other end is connected to the No. 5 pin of the optocoupler U2; one end of the resistor R3 is connected to the +5V DC power supply output by the switching power supply, and the other end is connected to the No. 1 pin of the comparator U3A; one end of the resistor R4 is connected to the +5V DC power supply output by the switching power supply, and the other end is connected to the No. 2 pin of the comparator U3B; one end of the resistor R5 is connected to the No. 6 pin of the comparator U3A, and the other end is grounded; one end of the resistor R6 is connected to the No. 3 pin of the comparator U3A, and the other end is connected to the No. 6 pin of the comparator U3A.

[0011] Furthermore, pin 1 of the single-chip microcomputer U4 is connected to the Vout pin of the low-voltage linear regulator U5, pin 8 is grounded, pin 9 is connected to pin 1, pin 11 is connected to pin 5 of the optical coupler U1, pin 12 is connected to pin 5 of the optical coupler U2, pin 20 is grounded, pin 23 is grounded, and pin 24 is connected to pin 1; pin 30 of the single-chip microcomputer U4 is the RS232 communication sending end, which is connected to the display screen end Pin 3 of port P3 and Pin 31 of MCU U4 are the RS232 communication receiving end, connected to Pin 2 of display port P3; Pin 35 of MCU U4 is grounded, Pin 36 is connected to Pin 1, Pin 37 is connected to Pin 2 of program write port P2, and Pin 38 is connected to Pin 3 of program write port P2; Pin 44 of MCU U4 is grounded, Pin 47 is grounded, and Pin 48 is connected to Pin 1.

[0012] Furthermore, pin 1 of the program writing port P2 is connected to the Vout pin of the low voltage linear regulator U5, and pin 4 is grounded; pin 1 of the display port P3 is grounded, and pin 4 is connected to the +5V DC power supply output by the switching power supply.

[0013] Furthermore, the signal processing module also includes a resistor R19 and a capacitor C7; one end of the resistor R19 is connected to the Vout pin of the low-voltage linear regulator U5, and the other end is connected to the pin 7 of the microcontroller U4; one end of the capacitor C7 is connected to the pin 7 of the microcontroller U4, and the other end is grounded.

[0014] Furthermore, the model of the diode D1 is 1N4007, and the model of the low-voltage linear regulator U5 is LM1117-3.3.

[0015] Furthermore, the comparator U3 and the comparator U3B are both of the type LMV339, the optocoupler U1 and the optocoupler U2 are both of the type 4N35; and the single-chip microcomputer U4 is of the type STM32L151C8.

[0016] Compared with the prior art, the beneficial effects of the utility model are as follows: the pulse test circuit for the gamma probe of the utility model can provide a stable DC power supply to the gamma probe, so that the gamma probe can work normally while collecting gamma pulse signals and performing cumulative calculation of the gamma pulse signals. Compared with the traditional gamma probe test method, the gamma value can be detected without the need for a ground system, a directional probe and a PC as necessary test equipment, which not only streamlines the test equipment, but also simplifies the test operation process, greatly improving the convenience of the test. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is the circuit schematic diagram of the power module of the utility model;

[0018] Figure 2 This is the circuit schematic diagram of the signal conversion module of the utility model;

[0019] Figure 3 This is the circuit schematic diagram of the signal processing module of the utility model. DETAILED DESCRIPTION

[0020] like Figures 1 to 3 The pulse test circuit for the gamma probe shown in the figure includes a power supply module, a signal conversion module and a signal processing module; the power supply module is used to convert the 220V, 50Hz common AC power supply into a +5V DC power supply, and provide a +5V DC power supply to the signal conversion module, and at the same time convert the +5V DC power supply into a +3.3V DC power supply, and provide a +3.3V DC power supply to the signal processing module; the signal conversion module is used to generate a current pulse signal after filtering the gamma pulse signal through a comparator and isolating it safely through an optocoupler; the signal processing module is used to collect the current pulse signal generated by the signal conversion module into a single-chip microcomputer for processing, calculate the gamma value, and send the gamma value to the display screen through the RS232 protocol.

[0021] The power supply module includes a switching power supply, a diode D1, a tantalum capacitor C2, a tantalum capacitor C3, a capacitor C4 and a low-voltage linear regulator U5; the anode of the diode D1 is connected to the +5V DC power supply output by the switching power supply, and the cathode is connected to the Vin (voltage input) pin of the low-voltage linear regulator U5; the anode of the tantalum capacitor C2 is connected to the Vin (voltage input) pin of the low-voltage linear regulator U5, and the cathode is grounded; the anode of the tantalum capacitor C3 is connected to the Vout (voltage output) pin of the low-voltage linear regulator U5, and the cathode is grounded; one end of the capacitor C4 is connected to the Vout (voltage output) pin of the low-voltage linear regulator U5, and the other end is grounded; the GND pin of the low-voltage linear regulator U5 is grounded.

[0022] In this embodiment, the model of the diode D1 is 1N4007, the model of the low voltage linear regulator U5 is LM1117-3.3, the capacitance of the tantalum capacitor C2 and the tantalum capacitor C3 are both 476 μF, and the capacitance of the capacitor C4 is 100 nF.

[0023] like Figure 1 As shown, the switching power supply POWER in the power supply module is connected to the 220V, 50Hz room power, and then the room power is converted into a +5V DC power supply, and then the power is provided to the circuit; after the low-voltage linear regulator U5 receives the +5V DC power provided by the switching power supply POWER, it is converted into a +3.3V DC power supply, and then the power is provided to the circuit.

[0024] The signal conversion module includes comparator U3A, comparator U3B, optocoupler U1 and optocoupler U2; pin 1 of comparator U3A is connected to pin 1 of optocoupler U1, pin 2 of comparator U3B is connected to pin 1 of optocoupler U2, pin 3 of comparator U3A is connected to +5V DC power output by switching power supply, pin 4 of comparator U3B is connected to pin 6 of comparator U3A, pin 5 of comparator U3B is connected to gamma signal input port 2, pin 7 of comparator U3A is connected to gamma signal input port 1, and pin 12 of comparator U3A is grounded; pins 2 and 4 of optocoupler U1 are both grounded, and pin 5 is connected to pin 11 of microcontroller U4; pins 2 and 4 of optocoupler U2 are both grounded, and pin 5 is connected to pin 12 of microcontroller U4.

[0025] The signal conversion module also includes resistors R1, R2, R3, R4, R5 and R6; one end of resistor R1 is connected to the Vout (voltage output) pin of the low-voltage linear regulator U5, and the other end is connected to pin 5 of the optocoupler U1; one end of resistor R2 is connected to the Vout (voltage output) pin of the low-voltage linear regulator U5, and the other end is connected to pin 5 of the optocoupler U2; one end of resistor R3 is connected to the +5V DC power supply output by the switching power supply, and the other end is connected to pin 1 of the comparator U3A; one end of resistor R4 is connected to the +5V DC power supply output by the switching power supply, and the other end is connected to pin 2 of the comparator U3B; one end of resistor R5 is connected to pin 6 of the comparator U3A, and the other end is grounded; one end of resistor R6 is connected to pin 3 of the comparator U3A, and the other end is connected to pin 6 of the comparator U3A.

[0026] In this embodiment, the comparator U3 and the comparator U3B are both of LMV339 type, and the optocoupler U1 and the optocoupler U2 are both of 4N35 type.

[0027] Comparator U3A and comparator U3B in the signal conversion module divide the voltage through resistors R5 and R6 respectively, so that the voltage on pin 6 of comparator U3A and pin 4 of comparator U3B is 2.5V. Comparator U3A and comparator U3B filter out interference signals below 2.5V through comparison, and then output them to optocoupler U1 and optocoupler U2 respectively, and finally convert them into current pulse signals and input them into microcontroller U4.

[0028] The signal processing module includes a single-chip microcomputer U4, a program writing port P2 and a display port P3. Pin 1 of the single-chip microcomputer U4 is connected to the Vout (voltage output) pin of the low-voltage linear regulator U5, pin 8 is grounded, pin 9 is connected to pin 1, pin 11 is connected to pin 5 of the optocoupler U1, pin 12 is connected to pin 5 of the optocoupler U2, pin 20 is grounded, pin 23 is grounded, and pin 24 is connected to pin 1; pin 30 of the single-chip microcomputer U4 is RS 232 communication sending end, connected to the display screen port P3 pin 3, the single-chip U4 pin 31 is the RS232 communication receiving end, connected to the display screen port P3 pin 2; single-chip U4 pin 35 is grounded, pin 36 is connected to pin 1, pin 37 is connected to the program write port P2 pin 2, pin 38 is connected to the program write port P2 pin 3; single-chip U4 pin 44 is grounded, pin 47 is grounded, and pin 48 is connected to pin 1. Pin 1 of the program write port P2 is connected to the Vout (voltage output) pin of the low-voltage linear regulator U5, and pin 4 is grounded; pin 1 of the display screen port P3 is grounded, and pin 4 is connected to the +5V DC power output of the switching power supply. The signal processing module also includes a resistor R19 and a capacitor C7; one end of the resistor R19 is connected to the Vout (voltage output) pin of the low-voltage linear regulator U5, and the other end is connected to the No. 7 pin of the microcontroller U4; one end of the capacitor C7 is connected to the No. 7 pin of the microcontroller U4, and the other end is grounded.

[0029] In this embodiment, the model of the single chip computer U4 is STM32L151C8, and the capacitance of the capacitor C7 is 100nF.

[0030] The voltage pulse signal of the gamma probe is converted into a current pulse signal after passing through the signal conversion module and transmitted to pins 11 and 12 of the single-chip microcomputer U4. After collecting the current pulse signal, the single-chip microcomputer U4 counts and calculates the pulse count and the pulse count collected every t seconds, and finally displays the test result of the gamma probe on the display screen.

[0031] The Vin input voltage range of the low-voltage linear regulator U5 in the power module of the utility model is between 4.75V and 10V, which has a relatively wide voltage range and reserves space for voltage fluctuations; and the input power supply is stabilized by the rectifier diode D1 before the voltage input Vin pin, and the input voltage and output voltage are stabilized by the capacitor and filtered to reduce noise.

[0032] The utility model uses 2 channels, which can simultaneously access the pulse signals of two gamma probes and measure the two gamma probes at the same time, which greatly improves the test efficiency of the gamma probes; the photoelectric couplers U1 and U2 can safely isolate the comparator output signal and convert the voltage pulse signal into a current pulse signal.

Claims

1. A pulse test circuit for a gamma probe, characterized in that: It includes a power module, a signal conversion module and a signal processing module; the power module is used to convert 220V, 50Hz AC power into a +5V DC power, and provide a +5V DC power to the signal conversion module, and at the same time convert the +5V DC power into a +3.3V DC power, and provide a +3.3V DC power to the signal processing module; the signal conversion module is used to generate a current pulse signal after filtering the gamma pulse signal through a comparator and isolating it through a photoelectric coupler; the signal processing module is used to collect the current pulse signal generated by the signal conversion module into a single-chip microcomputer to calculate the gamma value, and send the gamma value to the display screen for display.

2. The pulse test circuit for a gamma probe according to claim 1, characterized in that: The power module includes a switching power supply, a diode D1, a tantalum capacitor C2, a tantalum capacitor C3, a capacitor C4 and a low-voltage linear regulator U5; the anode of the diode D1 is connected to the +5V DC power supply output by the switching power supply, and the cathode is connected to the Vin pin of the low-voltage linear regulator U5; the anode of the tantalum capacitor C2 is connected to the Vin pin of the low-voltage linear regulator U5, and the cathode is grounded; the anode of the tantalum capacitor C3 is connected to the Vout pin of the low-voltage linear regulator U5, and the cathode is grounded; one end of the capacitor C4 is connected to the Vout pin of the low-voltage linear regulator U5, and the other end is grounded; the GND pin of the low-voltage linear regulator U5 is grounded.

3. The pulse test circuit for a gamma probe according to claim 2, characterized in that: The signal conversion module includes a comparator U3A, a comparator U3B, an optocoupler U1 and an optocoupler U2; pin 1 of the comparator U3A is connected to pin 1 of the optocoupler U1, pin 2 of the comparator U3B is connected to pin 1 of the optocoupler U2, pin 3 of the comparator U3A is connected to a +5V DC power supply output by a switching power supply, pin 4 of the comparator U3B is connected to pin 6 of the comparator U3A, pin 5 of the comparator U3B is connected to gamma signal input port 2, pin 7 of the comparator U3A is connected to gamma signal input port 1, and pin 12 of the comparator U3A is grounded.

4. The pulse test circuit for a gamma probe according to claim 3, characterized in that: The signal processing module includes a single chip microcomputer U4, pins 2 and 4 of the optical coupler U1 are both grounded, and pin 5 is connected to pin 11 of the single chip microcomputer U4; pins 2 and 4 of the optical coupler U2 are both grounded, and pin 5 is connected to pin 12 of the single chip microcomputer U4.

5. The pulse test circuit for a gamma probe according to claim 3, characterized in that: The signal conversion module also includes a resistor R1, a resistor R2, a resistor R3, a resistor R4, a resistor R5 and a resistor R6; one end of the resistor R1 is connected to the Vout pin of the low-voltage linear regulator U5, and the other end is connected to the No. 5 pin of the optocoupler U1; one end of the resistor R2 is connected to the Vout pin of the low-voltage linear regulator U5, and the other end is connected to the No. 5 pin of the optocoupler U2; one end of the resistor R3 is connected to the +5V DC power supply output by the switching power supply, and the other end is connected to the No. 1 pin of the comparator U3A; one end of the resistor R4 is connected to the +5V DC power supply output by the switching power supply, and the other end is connected to the No. 2 pin of the comparator U3B; one end of the resistor R5 is connected to the No. 6 pin of the comparator U3A, and the other end is grounded; one end of the resistor R6 is connected to the No. 3 pin of the comparator U3A, and the other end is connected to the No. 6 pin of the comparator U3A.

6. The pulse test circuit for a gamma probe according to claim 4, characterized in that: Pin 1 of the single-chip microcomputer U4 is connected to the Vout pin of the low-voltage linear regulator U5, pin 8 is grounded, pin 9 is connected to pin 1, pin 11 is connected to pin 5 of the optical coupler U1, pin 12 is connected to pin 5 of the optical coupler U2, pin 20 is grounded, pin 23 is grounded, and pin 24 is connected to pin 1; pin 30 of the single-chip microcomputer U4 is the RS232 communication sending end, connected to the display port P Pin 3 of MCU U4 and Pin 31 of MCU U4 are the RS232 communication receiving end, connected to Pin 2 of display port P3; Pin 35 of MCU U4 is grounded, Pin 36 is connected to Pin 1, Pin 37 is connected to Pin 2 of program write port P2, and Pin 38 is connected to Pin 3 of program write port P2; Pin 44 of MCU U4 is grounded, Pin 47 is grounded, and Pin 48 is connected to Pin 1.

7. The pulse test circuit for a gamma probe according to claim 6, characterized in that: Pin 1 of the program writing port P2 is connected to the Vout pin of the low voltage linear regulator U5, and pin 4 is grounded; pin 1 of the display port P3 is grounded, and pin 4 is connected to the +5V DC power supply output by the switching power supply.

8. The pulse test circuit for a gamma probe according to claim 4, characterized in that: The signal processing module also includes a resistor R19 and a capacitor C7; one end of the resistor R19 is connected to the Vout pin of the low voltage linear regulator U5, and the other end is connected to the No. 7 pin of the microcontroller U4; one end of the capacitor C7 is connected to the No. 7 pin of the microcontroller U4, and the other end is grounded.

9. The pulse test circuit for a gamma probe according to claim 2, characterized in that: The model of the diode D1 is 1N4007, and the model of the low-voltage linear regulator U5 is LM1117-3.

3.

10. The pulse test circuit for a gamma probe according to claim 4, characterized in that: The comparator U3 and the comparator U3B are both of the LMV339 type, the optocoupler U1 and the optocoupler U2 are both of the 4N35 type; the single-chip microcomputer U4 is of the STM32L151C8 type.

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