Methane alarm execution circuit

Abstract

The utility model discloses a kind of methane alarm executing circuit, comprising: methane detector, variable load module, amplification module, AD conversion module, control module, output detection module, display module and power supply module;Methane detector power supply end is powered by power supply module, methane detector output end is grounded by variable load module, the control end group of variable load module is connected to control module first output end group, control module can control variable load module resistance value change;Methane detector output end is connected to amplification module input end, amplification module output end is connected to AD conversion module input end, AD conversion module output end is connected to control module input end.The methane alarm executing circuit solves the problem that load resistance value at methane detector output end cannot be adjusted in prior art.

Description

Technical Field

[0001] This utility model relates to a methane alarm, specifically to an execution circuit for a methane alarm. Background Technology

[0002] Chinese patent discloses a methane temperature alarm with application number CN202323627069.0. The methane temperature alarm includes: an upper shell, a lower shell, a sensing and actuating component, and an alarm device. The upper shell and the lower shell are fastened together to form a chamber, and the sensing and actuating component and the alarm device are installed in the chamber. The sensing and actuating component includes: a start switch, a detection and control circuit, and a sensor device. The sensor device includes: a methane sensor and a temperature sensor. The methane sensor is used to detect ambient methane, and the temperature sensor is used to detect the temperature of the methane. The detection and control circuit is mounted on a circuit board and includes: an amplification module, an analog-to-digital converter chip U3, and a controller U1. The output terminal of the methane sensor is connected to the input terminal of the amplification module.

[0003] Although this methane smoke alarm solves the problem of excessively long wires between the start switch and the detection control circuit caused by installing the start switch on the upper or lower shell in the existing technology, the methane smoke alarm still has the following drawback: the load resistance at the output of the methane detector cannot be adjusted, making it impossible to know whether the load is suitable for the detection environment. Utility Model Content

[0004] This invention provides an execution circuit for a methane alarm, solving the problem in the prior art that the load resistance at the output terminal of the methane detector cannot be adjusted.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] This utility model discloses an execution circuit for a methane alarm, comprising: a methane detector, a variable load module, an amplification module, an AD conversion module, a control module, an output detection module, a display module, and a power supply module. The power supply module powers the methane detector's output terminal, which is grounded through the variable load module. The control terminal group of the variable load module is connected to the first output terminal group of the control module, allowing the control module to control the resistance change of the variable load module. The methane detector's output terminal is connected to the amplification module's input terminal, which in turn is connected to the AD conversion module's input terminal. The AD conversion module's output terminal is connected to the control module's input terminal. The power supply module powers the variable load module's power supply terminal, the amplification module's power supply terminal, the AD conversion module's power supply terminal, the output detection module's power supply terminal, the display module's power supply terminal, and the control module's power supply terminal. The methane detector's output terminal is connected to the output detection module's input terminal, which is connected to the control module's input terminal. The control module and the display module are communicatively connected.

[0007] Preferably, the variable load module includes: a fixed access load, a movable access load, and a controllable switch switching unit. The first end of the fixed access load is connected to the output end of the methane detector. The second end of both the fixed access load and the second end of the movable access load are grounded. The first end of the movable access load is connected to the first end of the fixed access load through a switch in the controllable switch switching unit.

[0008] Preferably, there are at least two active loads, and the controllable switch switching unit is provided with at least two switching parts and at least two control parts. Each control part controls one switching part, and the control terminals of all control parts form a control terminal group of the variable load module.

[0009] Preferably, the input detection module includes a direct sensing unit and an indirect sensing unit. The output terminal of the methane detector is connected to the high-voltage terminal of the direct sensing unit, the low-voltage terminal of the direct sensing unit is grounded, the indirect sensing unit is photoelectrically induced with the direct sensing unit, the high-voltage terminal of the indirect sensing unit is the power supply terminal of the input detection module, and the low-voltage terminal of the indirect sensing unit is grounded.

[0010] Preferably, the direct sensing unit is provided with a direct sensing part, the indirect sensing unit is provided with an indirect sensing part, and the direct sensing part and the indirect sensing part constitute a thyristor-type optocoupler.

[0011] Preferably, the methane alarm execution circuit further includes: an alarm module, a second output terminal of the control module connected to the control terminal of the alarm module, and a power supply module supplying power to the alarm module.

[0012] Preferably, the alarm module includes an alarm and an alarm driving unit, the power supply module supplies power to the alarm through the alarm driving unit, and the control terminal of the alarm driving unit is the control terminal of the alarm module.

[0013] Compared with the prior art, this utility model has the following beneficial effects: In this application, by setting a variable load module at the output terminal of the methane detector, the control module can control and adjust the resistance value of the variable load module. Furthermore, by setting an output detection module, the output voltage of the methane detector is detected, thereby determining whether the voltage at the output terminal of the methane detector has reached the required value. The display module can display the maximum and minimum voltage values ​​output by the methane detector. The control module determines the maximum and minimum voltage values ​​output by the methane detector based on the output voltage of the output detection module. This is a known procedure and is not protected.

[0014] Other advantages, objectives and features of this invention will be partly apparent from the following description, and partly understood by those skilled in the art through study and practice of this invention. Attached Figure Description

[0015] Figure 1This is a circuit diagram of the methane detector, variable load module, amplification module, and AD conversion module in the execution circuit of a methane alarm.

[0016] Figure 2 This is the circuit diagram for the output detection module.

[0017] Figure 3 This is a circuit diagram for the control module, alarm module, and display module. Detailed Implementation

[0018] To make the technical means, creative features, objectives and effects of this utility model clearer and easier to understand, the present utility model will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0019] like Figures 1 to 3 As shown, this utility model discloses an execution circuit for a methane alarm, including: a methane detector MQ, a variable load module, an amplification module, an AD conversion module, a control module, an output detection module, a display module, and a power supply module; the power supply terminal of the methane detector MQ is powered by the power supply module, the output terminal of the methane detector MQ is grounded through the variable load module, the control terminal group of the variable load module is connected to the first output terminal group of the control module, and the control module can control the resistance change of the variable load module; the output terminal of the methane detector MQ is connected to the input terminal of the amplification module, the output terminal of the amplification module is connected to the input terminal of the AD conversion module, the output terminal of the AD conversion module is connected to the input terminal of the control module, and the power supply module supplies power to the power supply terminals of the variable load module, the amplification module, the AD conversion module, the output detection module, the display module, and the control module; the output terminal of the methane detector MQ is connected to the input terminal of the output detection module, the output terminal of the output detection module is connected to the input terminal of the control module, and the control module and the display module are communicatively connected.

[0020] In this application, the ground terminal GND of the methane detector MQ is grounded through resistor R1, and the power supply terminal of the methane detector MQ is connected to the output terminal of the power supply module, which outputs a 5V voltage.

[0021] In this application, the variable load module includes: a fixed connected load R2, a movable connected load (R5, R6, R7, or R8), and a controllable switch unit. The first terminal of the fixed connected load R2 is connected to the output terminal of the methane detector MQ. Both the second terminals of the fixed connected load R2 and the second terminal of the movable connected load are grounded. The first terminal of the movable connected load is connected to the first terminal of the fixed connected load R2 via a switch in the controllable switch unit. The controllable switch unit controls whether the movable connected load is connected in parallel with the fixed connected load R2, and also controls the number of movable connected loads in parallel, thereby controlling the resistance value of the fixed connected load R2 and the movable connected loads in parallel. The controllable switch unit, which controls whether the movable connected load is connected in parallel, avoids temperature drift caused by temperature changes during the sliding process of a sliding rheostat, thus preventing significant impact on resistance adjustment.

[0022] In this application, there are at least two active loads. The controllable switch unit is provided with at least two switching sections and at least two control sections. Each control section controls one switching section, and the control terminals of all control sections form a control terminal group for the variable load module. When a high level is applied to the control terminal of a control section, the switching section is closed. When a low level is applied to the control terminal of a control section, the switching section is opened.

[0023] In this application, the controllable switch switching unit uses a controllable switch chip U2, which is an ADG1611 model chip. The ground terminal GND of the controllable switch chip U2 is grounded, and its power supply terminal VDD is powered by the power supply module. The first terminal of the active load R5 is connected to pin D1 of the controllable switch chip U2; the first terminal of the active load R6 is connected to pin D2 of the controllable switch chip U2; the first terminal of the active load R7 is connected to pin D3 of the controllable switch chip U2; the first terminal of the active load R8 is connected to pin D4 of the controllable switch chip U2; and pins S1, S2, S3, and S4 of the controllable switch chip U2 are all connected to the first terminal of the fixed load R2. Pins IN1, IN2, IN3, and IN4 of the controllable switch chip U2 are the control terminal group of the variable load module. When IN1 is high, pins D1 and S1 are closed; when IN2 is high, pins D2 and S2 are closed; when IN3 is high, pins D3 and S3 are closed; and when IN4 is high, pins D4 and S4 are closed. When IN1 is low, pins D1 and S1 are open; when IN2 is low, pins D2 and S2 are open; when IN3 is low, pins D3 and S3 are open; and when IN4 is low, pins D4 and S4 are open.

[0024] The amplification module includes: resistors R3, R4, and R9, capacitors C1 and C2, and amplifier U1. The first end of resistor R3 is connected to the output of the power supply module, and the second end of resistor R3 is grounded through resistor R4. The second end of resistor R3 is connected to the non-inverting input of amplifier U1. The inverting input of amplifier U1 is the input of the amplification module. The inverting input of amplifier U1 is connected to the first end of resistor R9 and the first end of capacitor C1. The second ends of resistor R9 and the second ends of capacitor C1 are connected to the output of amplifier U1. The power supply of amplifier U1 is powered by the output of the power supply module. The power supply of amplifier U1 is connected to the first end of capacitor C2, and the second end of capacitor C2 is grounded.

[0025] The AD conversion module includes an AD conversion chip U3. The output terminal CHI of the AD conversion chip U3 is the input terminal of the AD conversion module, and the output terminal DI of the AD conversion chip U3 is the output terminal of the AD conversion module. The power supply terminal VCC of the AD conversion chip U3 is powered by the output terminal of the power supply module.

[0026] In this application, the input detection module includes: a direct sensing unit and an indirect sensing unit. The output terminal of the methane detector MQ is connected to the high-voltage terminal of the direct sensing unit, the low-voltage terminal of the direct sensing unit is grounded, the indirect sensing unit is photoelectrically induced with the direct sensing unit, the high-voltage terminal of the indirect sensing unit is the power supply terminal of the input detection module, and the low-voltage terminal of the indirect sensing unit is grounded.

[0027] In this application, the direct sensing unit is provided with a direct sensing part, and the indirect sensing unit is provided with an indirect sensing part. The direct sensing part and the indirect sensing part constitute a thyristor-type optocoupler U4. The direct sensing part is a light-emitting diode in the thyristor-type optocoupler U4, and the indirect sensing part is a thyristor in the thyristor-type optocoupler U4.

[0028] The anode of the direct sensing unit is the input terminal of the input detection module, the cathode of the direct sensing unit is connected to the collector of transistor Q1, the emitter of transistor Q1 is grounded, and the base of transistor Q1 is connected to the first output terminal of the control module. The first terminal of the indirect sensing unit is connected to the output terminal of the power supply module, and the second terminal of the indirect sensing unit is grounded through resistor R10. The second terminal of the indirect sensing unit is the output terminal of the input detection module. This enables the control module to control whether the direct sensing unit is working by controlling transistor Q1.

[0029] In this application, the methane alarm execution circuit further includes: an alarm module, a second output terminal of the control module connected to the control terminal of the alarm module, and a power supply module supplying power to the alarm module.

[0030] Preferably, the alarm module includes an alarm BUZ1 and an alarm drive unit. The power supply module supplies power to the alarm BUZ1 through the alarm drive unit, and the control terminal of the alarm drive unit serves as the control terminal for the alarm module. This enables control of whether the alarm BUZ1 alarms via the alarm drive unit.

[0031] The alarm drive unit includes a resistor R11 and a transistor Q2. The first end of the resistor R11 is connected to the output of the power supply module, the second end of the resistor R11 is connected to the collector of the transistor Q2, the emitter of the transistor Q2 is connected to the positive terminal of the alarm BUZ1, and the negative terminal of the alarm BUZ1 is grounded.

[0032] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model and are not intended to limit it. Although this utility model has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of this utility model without departing from the spirit and scope of the technical solutions of this utility model, and all such modifications or substitutions should be covered within the scope of the claims of this utility model.

Claims

1. A methane alarm actuator circuit, characterized in that, include: Methane detector, variable load module, amplification module, AD conversion module, control module, output detection module, display module, and power supply module; The power supply terminal of the methane detector is powered by the power supply module, and the output terminal of the methane detector is grounded through the variable load module. The control terminal group of the variable load module is connected to the first output terminal group of the control module, and the control module can control the resistance value of the variable load module. The output of the methane detector is connected to the input of the amplification module, the output of the amplification module is connected to the input of the AD conversion module, the output of the AD conversion module is connected to the input of the control module, and the power supply module provides power to the variable load module, the amplification module, the AD conversion module, the output detection module, the display module, and the control module. The output of the methane detector is connected to the input of the output detection module, the output of the output detection module is connected to the input of the control module, and the control module is communicatively connected to the display module.

2. The methane alarm execution circuit according to claim 1, characterized in that, The variable load module includes: a fixed access load, a movable access load, and a controllable switch switching unit. The first terminal of the fixed access load is connected to the output terminal of the methane detector. The second terminals of both the fixed access load and the movable access load are grounded. The first terminal of the movable access load is connected to the first terminal of the fixed access load through the switch section in the controllable switch switching unit.

3. The methane alarm execution circuit according to claim 2, characterized in that, There are at least two active loads. The controllable switch switching unit is equipped with at least two switching sections and at least two control sections. Each control section controls one switching section. The control terminals of all control sections form the control terminal group of the variable load module.

4. The methane alarm actuator circuit according to claim 3, characterized in that, The input detection module includes a direct sensing unit and an indirect sensing unit. The output terminal of the methane detector is connected to the high-voltage terminal of the direct sensing unit, and the low-voltage terminal of the direct sensing unit is grounded. The indirect sensing unit is photoelectrically induced to the direct sensing unit. The high-voltage terminal of the indirect sensing unit is the power supply terminal of the input detection module, and the low-voltage terminal of the indirect sensing unit is grounded.

5. The methane alarm execution circuit according to claim 4, characterized in that, The direct sensing unit is provided with a direct sensing part, and the indirect sensing unit is provided with an indirect sensing part. The direct sensing part and the indirect sensing part constitute a thyristor-type optocoupler.

6. The methane alarm actuator circuit according to any one of claims 1 to 5, characterized in that, Also includes: The alarm module and the control module's second output terminal are connected to the alarm module's control terminal, and the power supply module supplies power to the alarm module.

7. The methane alarm execution circuit according to claim 6, characterized in that, The alarm module includes an alarm and an alarm drive unit. The power supply module supplies power to the alarm through the alarm drive unit, and the control terminal of the alarm drive unit is the control terminal of the alarm module.

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