A portable detector for mine sensors

Abstract

The application provides a mine sensor portable detector. The mine sensor portable detector comprises a frequency input interface, a voltage-current conversion circuit, a current input circuit and a main control circuit; the frequency input interface is configured to receive a frequency signal output by a frequency signal type sensor; a capture signal input end of the main control circuit is connected with the frequency input interface; a first signal output end of the main control circuit is connected with an input end of the voltage-current conversion circuit; an output end of the voltage-current conversion circuit is connected with an input end of the current input circuit; and an output end of the current input circuit is connected with a first analog signal input end of the main control circuit; and the input end of the current input circuit is also used for receiving a current signal output by a current signal type sensor. The application can solve the problem of inconvenient sensor testing.

Description

Technical Field

[0001] This application relates to the field of automatic detection technology, and in particular to a portable detector for mining sensors. Background Technology

[0002] Mining sensors play a crucial role in coal mine safety production. They are mainly used to monitor changes in the concentration of various gases, dust, temperature, and humidity in real time, and provide timely data support. When the gas concentration or other standards are detected to exceed safety standards, the sensors will issue an alarm to remind staff to take appropriate measures to avoid accidents.

[0003] To ensure the detection accuracy of sensors, it is necessary to test the sensor detection results. Various types of sensors are used in coal mine production, including sensors for methane, carbon monoxide, oxygen, dust, carbon dioxide, hydrogen sulfide, and noise. The interfaces and signals of various sensor manufacturers are inconsistent, which makes it inconvenient to test the sensors. Utility Model Content

[0004] This application provides a portable sensor detector for mining to solve the problem of inconvenient testing of existing sensors.

[0005] This application provides a portable detector for mining sensors, including a frequency input interface, a voltage-to-current conversion circuit, a current input circuit, and a main control circuit; The frequency input interface is configured to receive frequency signals output by a frequency signal type sensor. The capture signal input terminal of the main control circuit is connected to the frequency input interface. The first signal output terminal of the main control circuit is connected to the input terminal of the voltage-to-current conversion circuit. The output terminal of the voltage-to-current conversion circuit is connected to the input terminal of the current input circuit. The output terminal of the current input circuit is connected to the first analog signal input terminal of the main control circuit. The input terminal of the current input circuit is also used to receive the current signal output by the current signal type sensor.

[0006] In one embodiment of this application, an anti-interference circuit is further provided between the frequency input interface and the capture signal input terminal of the main control circuit; The anti-interference circuit includes a comparator U3. The first input terminal of the comparator U3 is connected to the frequency input interface, the second input terminal of the comparator U3 is connected to the threshold voltage, and the output terminal of the comparator U3 is connected to the capture signal input terminal of the main control circuit.

[0007] In one embodiment of this application, the portable detector for mining sensors further includes resistors R14 and R16; The first end of the resistor R14 is connected to the power supply, and the second end of the resistor R14 is grounded through the resistor R16. The second end of the resistor R14 serves as the threshold voltage.

[0008] In one embodiment of this application, the voltage-to-current conversion circuit includes a voltage-to-current converter U4, a switching transistor Q3, a resistor R20, and an inductor W3. The signal source input terminal of the voltage-to-current converter U4 is the input terminal of the voltage-to-current conversion circuit and is connected to the first signal output terminal of the main control circuit. The drive output terminal of the voltage-to-current converter U4 is connected to the control terminal of the switching transistor Q3. The first terminal of the switching transistor Q3 is connected to the current output terminal of the voltage-to-current converter U4. The second terminal of the switching transistor Q3 is connected to the first terminal of the inductor W3 through the resistor R20. The second terminal of the inductor W3 is the output terminal of the voltage-to-current conversion circuit.

[0009] In one embodiment of this application, the current input circuit includes a resistor R12, the first end of the resistor R12 is the first end of the current input circuit, the second end of the resistor R12 is the second end of the current input circuit, and is connected to the first analog signal input terminal of the main control circuit.

[0010] In one embodiment of this application, the power supply of the portable mining sensor is provided by a battery pack, which includes a first battery, a second battery, and a third battery. The positive terminal of the first battery is the positive terminal of the battery pack, and the negative terminal of the third battery is the negative terminal of the battery pack. The portable detector for mining sensors also includes a battery protection circuit, which includes a battery protection module U1, a switching transistor Q1, and a switching transistor Q2. The first power input terminal of the battery protection module U1 is connected to the positive terminal of the first battery, the second power input terminal of the battery protection module U1 is connected to the positive terminal of the second battery, and the third power input terminal of the battery protection module U1 is connected to the positive terminal of the third battery. The overcharge detection output terminal of the battery protection module U1 is connected to the control terminal of the switching transistor Q2. The first terminal of the switching transistor Q2 is connected to the negative terminal of the battery pack, and the second terminal of the switching transistor Q2 is used to connect to an external power supply interface. The over-discharge detection output terminal of the battery protection module U1 is connected to the control terminal of the switching transistor Q1. The first terminal of the switching transistor Q1 is used to connect to the external power supply interface, and the second terminal of the switching transistor Q1 is connected to the negative terminal of the battery pack.

[0011] In one embodiment of this application, the portable detector for mining sensors further includes a current display circuit. The input terminal of the current display circuit is connected to the second signal output terminal of the main control circuit, and is used to display the current signal input to the current input circuit.

[0012] In one embodiment of this application, the portable mining sensor detector further includes a power detection circuit and a power display circuit; The power detection circuit includes a resistor R9 and a capacitor C7. The first end of the resistor R9 is connected to the power supply, and the second end of the resistor R9 is grounded through the capacitor C7. The second end of the resistor R9 is connected to the second analog circuit input terminal of the main control circuit, and the third signal output terminal of the main control circuit is connected to the input terminal of the power display circuit.

[0013] The working principle and beneficial effects of the portable detector for mining sensors provided in this application are as follows: In this embodiment, for frequency signal type sensors, i.e., sensors whose output signal is a frequency signal, the frequency signal output by such sensors can be connected to the frequency input interface of the portable mining sensor detector, and then connected to the capture signal input terminal of the main control circuit via the frequency input interface. The capture module inside the main control circuit collects the rising or falling edge of the frequency signal, and uses an internal timer to count the number of pulses per unit time to obtain the frequency of the frequency signal. Then, according to the magnitude of the frequency, a corresponding voltage command is output to the digital-to-analog converter (DAC) module, and a voltage signal of the corresponding level is output at the first signal output terminal of the main control circuit.

[0014] The voltage signal output from the first signal output terminal of the main control circuit is connected to the voltage-to-current conversion circuit, which converts the input voltage signal into a current signal and inputs it to the input terminal of the current input circuit. The output terminal of the current input circuit is connected to the first analog signal input terminal (U1.19) of the main control circuit. The main control circuit can obtain the magnitude of the frequency signal by reading the signal from the first analog signal input terminal.

[0015] For current signal type sensors, that is, sensors whose output signal is a current signal, the circuit signal output by this type of sensor can be directly connected to the input terminal of the current input circuit, and then connected to the first analog signal input terminal of the main control circuit through the current input circuit.

[0016] Therefore, the portable sensor detector for mining in this embodiment can be adapted to both frequency signal type sensors and current signal type sensors, making it convenient to test different types of sensors. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the anti-interference circuit provided in the embodiments of this application; Figure 2 This is a schematic diagram of the voltage-to-current conversion circuit provided in the embodiments of this application; Figure 3 This is a schematic diagram of the current input circuit provided in an embodiment of this application; Figure 4 This is a schematic diagram of the battery protection circuit provided in an embodiment of this application; Figure 5 This is a schematic diagram of the power display circuit provided in an embodiment of this application; Figure 6 This is an electrical schematic diagram of the portable mining sensor detector provided in the embodiments of this application; Figure 7 This is a schematic diagram of the overall appearance of the portable mining sensor detector provided in the embodiments of this application. Detailed Implementation

[0019] To enable those skilled in the art to better understand this solution, the technical solutions in the embodiments of this solution will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this solution. Based on the embodiments of this solution, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this solution.

[0020] The term "comprising" and any other variations thereof in the specification, claims, and accompanying drawings of this invention mean "including but not limited to," and are intended to cover a non-exclusive inclusion, not limited to the examples listed herein. Furthermore, the terms "first" and "second," etc., are used to distinguish different objects, not to describe a specific order.

[0021] The implementation of this application will be described in detail below with reference to the specific accompanying drawings: This embodiment of the portable detector for mining sensors includes a frequency input interface, a voltage-to-current conversion circuit, a current input circuit, and a main control circuit; The frequency input interface is configured to receive the frequency signal output by the frequency signal type sensor. The capture signal input terminal of the main control circuit is connected to the frequency input interface. The first signal output terminal of the main control circuit is connected to the input terminal of the voltage-to-current conversion circuit. The output terminal of the voltage-to-current conversion circuit is connected to the input terminal of the current input circuit. The output terminal of the current input circuit is connected to the first analog signal input terminal of the main control circuit. The input terminal of the current input circuit is also used to receive the current signal output by the current signal type sensor.

[0022] In this embodiment, for frequency signal type sensors, i.e., sensors whose output signal is a frequency signal, the frequency signal output by such sensors can be connected to the frequency input interface of the portable mining sensor detector, and then connected to the capture signal input terminal of the main control circuit via the frequency input interface. The capture module inside the main control circuit collects the rising or falling edge of the frequency signal, and uses an internal timer to count the number of pulses per unit time to obtain the frequency of the frequency signal. Then, according to the magnitude of the frequency, a corresponding voltage command is output to the digital-to-analog converter (DAC) module, and a voltage signal of the corresponding level is output at the first signal output terminal of the main control circuit.

[0023] The voltage signal output from the first signal output terminal of the main control circuit is connected to the voltage-to-current conversion circuit, which converts the input voltage signal into a current signal and inputs it to the input terminal of the current input circuit. The output terminal of the current input circuit is connected to the first analog signal input terminal (U1.19) of the main control circuit. The main control circuit can obtain the magnitude of the frequency signal by reading the signal from the first analog signal input terminal.

[0024] For current signal type sensors, that is, sensors whose output signal is a current signal, the circuit signal output by this type of sensor can be directly connected to the input terminal of the current input circuit, and then connected to the first analog signal input terminal of the main control circuit through the current input circuit.

[0025] Therefore, the portable sensor detector for mining in this embodiment can be adapted to both frequency signal type sensors and current signal type sensors, making it convenient to test different types of sensors.

[0026] Reference Figure 1 In one exemplary embodiment of this application, an anti-interference circuit is further provided between the frequency input interface and the capture signal input terminal of the main control circuit; The anti-interference circuit includes comparator U3. The first input terminal of comparator U3 is connected to the frequency input interface, the second input terminal of comparator U3 is connected to the threshold voltage, and the output terminal of comparator U3 is connected to the capture signal input terminal of the main control circuit.

[0027] In this embodiment, the frequency signal received by the frequency input interface is a square wave signal. During the high level period of the square wave signal, the voltage of the frequency signal is greater than the threshold voltage, and the comparator U3 outputs a high level. During the low level period of the square wave signal, the voltage of the frequency signal is less than the threshold voltage, and the comparator U3 outputs a low level. Thus, when the high level voltage of the frequency signal is greater than the threshold voltage, the comparator U3 outputs a square wave signal to the capture signal input terminal of the main control circuit.

[0028] When interference signals are present at the frequency input interface, because the voltage level of the interference signals is low, typically less than the threshold voltage, comparator U3 outputs a continuous low-level signal to the capture signal input terminal of the main control circuit. This means the main control circuit cannot receive the frequency signal, thus preventing interference signals from being input to the capture signal input terminal of the main control circuit. The threshold voltage can be designed according to actual needs; for example, in this embodiment, it can be set to 1.55V.

[0029] Reference Figure 1 In one exemplary embodiment of this application, the portable detector for mining sensors further includes resistors R14 and R16; The first end of resistor R14 is connected to the power supply, and the second end of resistor R14 is grounded through resistor R16. The second end of resistor R14 serves as the threshold voltage.

[0030] In this embodiment, resistors R14 and R16 form a series voltage divider circuit. The voltage divided by resistor R16 serves as the threshold voltage. The magnitude of the threshold voltage can be adjusted by adjusting the resistance values ​​of resistors R14 and R16 according to actual needs.

[0031] Reference Figure 2 In one exemplary embodiment of this application, the voltage-to-current conversion circuit includes a voltage-to-current converter U4, a switching transistor Q3, a resistor R20, and an inductor W3. The signal source input terminal of the voltage-to-current converter U4 is the input terminal of the voltage-to-current conversion circuit and is connected to the first signal output terminal of the main control circuit. The drive output terminal VG of the voltage-to-current converter U4 is connected to the control terminal of the switching transistor Q3. The first terminal of the switching transistor Q3 is connected to the current output terminal IS of the voltage-to-current converter U4. The second terminal of the switching transistor Q3 is connected to the first terminal of the inductor W3 through the resistor R20. The second terminal of the inductor W3 is the output terminal of the voltage-to-current conversion circuit.

[0032] In this embodiment, the voltage-to-current converter U4 specifically adopts the XTR111AIDGQR. The voltage-to-current converter U4 can convert the voltage signal output from the first signal output terminal of the main control circuit into a current signal. This current signal is amplified by the switching transistor Q3 and then output to the current input circuit. Among them, the inductor W3 plays the role of current filtering.

[0033] Reference Figure 3In one exemplary embodiment of this application, the current input circuit includes a resistor R12, the first end of the resistor R12 is the first end of the current input circuit, the second end of the resistor R12 is the second end of the current input circuit, and is connected to the first analog signal input terminal of the main control circuit.

[0034] In this embodiment, the current signal output by the voltage-to-current conversion circuit or the current signal output by the sensor is connected to the current input circuit, which converts resistor R12 into a voltage signal. This voltage signal is connected to the first analog signal input terminal of the main control circuit, and the analog-to-digital conversion module inside the main control circuit converts the analog voltage signal into a digital signal, so that the main control circuit can read the voltage signal and obtain the current signal output by the voltage-to-current conversion circuit or the current signal output by the sensor.

[0035] In one exemplary embodiment of this application, the power supply of the portable detector for mining sensors is provided by a battery pack, which includes a first battery, a second battery, and a third battery. The positive terminal of the first battery is the positive terminal of the battery pack, and the negative terminal of the third battery is the negative terminal of the battery pack. The portable detector for mining sensors also includes a battery protection circuit, which includes a battery protection module U1, a switching transistor Q1, and a switching transistor Q2. The first power input terminal of the battery protection module U1 is connected to the positive terminal of the first battery, the second power input terminal of the battery protection module U1 is connected to the positive terminal of the second battery, and the third power input terminal of the battery protection module U1 is connected to the positive terminal of the third battery. The overcharge detection output terminal of the battery protection module U1 is connected to the control terminal of the switching transistor Q2. The first terminal of the switching transistor Q2 is connected to the negative terminal of the battery pack, and the second terminal of the switching transistor Q2 is used to connect to the external power supply interface. The over-discharge detection output of the battery protection module U1 is connected to the control terminal of the switching transistor Q1. The first terminal of the switching transistor Q1 is used to connect to the external power supply interface, and the second terminal of the switching transistor Q1 is connected to the negative terminal of the battery pack.

[0036] In this embodiment, the portable detector for mining sensors has a built-in battery pack and a charging interface, which can be charged by an external 12V charger, eliminating the need for a temporary external power supply and facilitating the testing of the sensors.

[0037] To prevent overcharging or over-discharging of the battery pack, this embodiment also includes a battery protection circuit. Specifically, the battery protection module uses the CM1033-DS. The CM1033 series is a protection chip specifically designed for 3-cell lithium / iron battery or polymer battery packs. It has built-in high-precision voltage detection circuit and current detection circuit. By detecting the voltage, charging and discharging current, and other information of each battery cell, it can realize protection functions such as overcharging, over-discharging, overcurrent discharge, short circuit, and overcurrent charging.

[0038] Specifically, the positive terminals of the first, second, and third batteries are connected to the three power input terminals VC1 / VC2 / VC3 of the battery protection module U1, respectively. When the voltage of any battery rises above the upper voltage limit (VOC) and lasts for more than the first time threshold (TOC), the output of the overcharge detection output terminal CO of the battery protection module U1 will reverse, controlling the switch Q2 to turn off and stop charging. Similarly, when the voltage of any battery drops above the upper voltage limit (VOD) and lasts for more than the second time threshold (TOD), the output of the over-discharge detection output terminal DO of the battery protection module U1 will reverse, controlling the switch Q1 to turn off and stop discharging.

[0039] Reference Figure 4 In one exemplary embodiment of this application, the portable detector for mining sensors further includes a current display circuit. The input terminal of the current display circuit is connected to the second signal output terminal of the main control circuit, and is used to display the current signal input to the current input circuit.

[0040] In this embodiment, the output terminal of the current input circuit is connected to the first analog signal input terminal of the main control circuit. After the main control circuit reads the current signal, it displays the current data through the current display circuit.

[0041] Reference Figure 5 In one exemplary embodiment of this application, the portable mining sensor detector further includes a power detection circuit and a power display circuit; The power detection circuit includes a resistor R9 and a capacitor C7. The first end of the resistor R9 is connected to the power supply, and the second end of the resistor R9 is grounded through the capacitor C7. The second end of the resistor R9 is connected to the second analog circuit input terminal of the main control circuit, and the third signal output terminal of the main control circuit is connected to the input terminal of the power display circuit.

[0042] In this embodiment, resistor R9 and capacitor C7 are connected in series between the 3.3V power supply and ground. The main control circuit can obtain the power supply voltage by detecting the voltage at the second end of resistor R9, and then display the power supply voltage in the power display circuit.

[0043] In addition, refer to Figure 6 Regarding the interface, this embodiment features a sensor plug that can be directly plugged into a sensor from a certain coal research institute using a matching plug. Considering the large variety of sensor models on-site, and the fact that some sensors lack sockets, the tester is equipped with wiring terminals for easy direct wiring.

[0044] Reference Figure 7 The overall appearance of this embodiment is shown. Considering the requirements for use in coal mines and other explosive areas, selecting a suitable explosion-proof electrical enclosure material is particularly crucial. Therefore, the enclosure of the tester in this embodiment is specifically made of ABS plastic.

[0045] In summary, this embodiment solves the problem of inconsistent sensor signal formats, is applicable to most mining sensors, and can receive 4-20mA current signals and 200-2000Hz frequency signals. During use, no external power supply or measuring instruments are required, operation is simple, data is intuitive, and safety and convenience are high, making it a promising candidate for widespread application.

[0046] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A portable detector for mining applications, characterized in that, This includes a frequency input interface, a voltage-to-current conversion circuit, a current input circuit, and a main control circuit; The frequency input interface is configured to receive frequency signals output by a frequency signal type sensor. The capture signal input terminal of the main control circuit is connected to the frequency input interface. The first signal output terminal of the main control circuit is connected to the input terminal of the voltage-to-current conversion circuit. The output terminal of the voltage-to-current conversion circuit is connected to the input terminal of the current input circuit. The output terminal of the current input circuit is connected to the first analog signal input terminal of the main control circuit. The input terminal of the current input circuit is also used to receive the current signal output by the current signal type sensor.

2. The portable detection instrument for mining sensors as described in claim 1, characterized in that, An anti-interference circuit is also provided between the frequency input interface and the capture signal input terminal of the main control circuit; The anti-interference circuit includes a comparator U3. The first input terminal of the comparator U3 is connected to the frequency input interface, the second input terminal of the comparator U3 is connected to the threshold voltage, and the output terminal of the comparator U3 is connected to the capture signal input terminal of the main control circuit.

3. The portable detection instrument for mining sensors as described in claim 2, characterized in that, It also includes resistors R14 and R16; The first end of the resistor R14 is connected to the power supply, and the second end of the resistor R14 is grounded through the resistor R16. The second end of the resistor R14 serves as the threshold voltage.

4. The portable detection instrument for mining sensors as described in claim 1, characterized in that, The voltage-to-current conversion circuit includes a voltage-to-current converter U4, a switching transistor Q3, a resistor R20, and an inductor W3. The signal source input terminal of the voltage-to-current converter U4 is the input terminal of the voltage-to-current conversion circuit and is connected to the first signal output terminal of the main control circuit. The drive output terminal of the voltage-to-current converter U4 is connected to the control terminal of the switching transistor Q3. The first terminal of the switching transistor Q3 is connected to the current output terminal of the voltage-to-current converter U4. The second terminal of the switching transistor Q3 is connected to the first terminal of the inductor W3 through the resistor R20. The second terminal of the inductor W3 is the output terminal of the voltage-to-current conversion circuit.

5. A portable detection instrument for mining sensors as described in claim 1, characterized in that, The current input circuit includes a resistor R12, the first end of which is the first terminal of the current input circuit, and the second end of which is the second terminal of the current input circuit, and is connected to the first analog signal input terminal of the main control circuit.

6. A portable detection instrument for mining sensors as described in claim 1, characterized in that, The portable detector for mining sensors is powered by a battery pack, which includes a first battery, a second battery, and a third battery. The positive terminal of the first battery is the positive terminal of the battery pack, and the negative terminal of the third battery is the negative terminal of the battery pack. The portable detector for mining sensors also includes a battery protection circuit, which includes a battery protection module U1, a switching transistor Q1, and a switching transistor Q2. The first power input terminal of the battery protection module U1 is connected to the positive terminal of the first battery, the second power input terminal of the battery protection module U1 is connected to the positive terminal of the second battery, and the third power input terminal of the battery protection module U1 is connected to the positive terminal of the third battery. The overcharge detection output terminal of the battery protection module U1 is connected to the control terminal of the switching transistor Q2. The first terminal of the switching transistor Q2 is connected to the negative terminal of the battery pack, and the second terminal of the switching transistor Q2 is used to connect to an external power supply interface. The over-discharge detection output terminal of the battery protection module U1 is connected to the control terminal of the switching transistor Q1. The first terminal of the switching transistor Q1 is used to connect to the external power supply interface, and the second terminal of the switching transistor Q1 is connected to the negative terminal of the battery pack.

7. A portable detection instrument for mining sensors as described in claim 1, characterized in that, It also includes a current display circuit, the input terminal of which is connected to the second signal output terminal of the main control circuit, for displaying the current signal input to the current input circuit.

8. A portable detection instrument for mining sensors as described in claim 1, characterized in that, It also includes a power detection circuit and a power display circuit; The power detection circuit includes a resistor R9 and a capacitor C7. The first end of the resistor R9 is connected to the power supply, and the second end of the resistor R9 is grounded through the capacitor C7. The second end of the resistor R9 is connected to the second analog circuit input terminal of the main control circuit, and the third signal output terminal of the main control circuit is connected to the input terminal of the power display circuit.

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