阅读说明：本技术 一种隧道施工用智能安全帽 (Intelligent safety helmet for tunnel construction ) 是由 李化云 赵晨夕 代云昊 陈晔磊 周伟 于 2021-03-22 设计创作，主要内容包括：一种隧道施工用智能安全帽,包括安全帽本体、蓄电池、电源开关、充电插座；还具有气体探测电路、粉尘探测电路及高度探测电路、无线发射电路、无线接收电路、温度探测电路；安全帽本体的上端有壳体,蓄电池、电源开关、充电插座、气体探测电路、粉尘探测电路及高度探测电路、无线发射电路、温度探测电路安装在壳体内并电性连接；无线接收电路安装在在施工区域附近的管理室内。本发明每个施工人员佩戴,当附近发生瓦斯泄漏及粉尘超标时,能第一时间发出不同警示信号,提示施工人员及时撤离现场,当头部接近头顶作业面等一定距离时,能提示施工人员注意安全,还能在温度超标时,提示施工人员暂停作业防中暑,且发生瓦西泄漏时,还能通知管理人员。(An intelligent safety helmet for tunnel construction comprises a safety helmet body, a storage battery, a power switch and a charging socket; the device is also provided with a gas detection circuit, a dust detection circuit, a height detection circuit, a wireless transmitting circuit, a wireless receiving circuit and a temperature detection circuit; the upper end of the safety helmet body is provided with a shell, and the storage battery, the power switch, the charging socket, the gas detection circuit, the dust detection circuit, the height detection circuit, the wireless transmitting circuit and the temperature detection circuit are arranged in the shell and are electrically connected; the wireless receiving circuit is installed in a management room near a construction area. The warning device is worn by each constructor, when gas leakage and dust exceeding the standard occur nearby, different warning signals can be sent out at the first time to prompt the constructor to withdraw from the site in time, when the head part is close to the operation surface on the top of the head and the like for a certain distance, the constructor can be prompted to pay attention to safety, when the temperature exceeds the standard, the constructor can be prompted to pause the operation to prevent heatstroke, and when the gas leakage and the dust exceeding the standard occur, the constructor can be notified.)

1. An intelligent safety helmet for tunnel construction comprises a safety helmet body, a storage battery, a power switch and a charging socket; it is characterized by also comprising a gas detection circuit, a dust detection circuit, a height detection circuit, a wireless transmitting circuit, a wireless receiving circuit and a temperature detection circuit; the upper end of the safety helmet body is provided with a shell, and the storage battery, the power switch, the charging socket, the gas detection circuit, the dust detection circuit, the height detection circuit, the wireless transmitting circuit and the temperature detection circuit are arranged in the shell; the wireless receiving circuit is installed in a management room near a construction area; the storage battery is electrically connected with the two ends of the power supply input of the gas detection circuit, the dust detection circuit, the height detection circuit and the temperature detection circuit respectively; the power supply output end of the gas detection circuit is electrically connected with the power supply input end of the wireless transmitting circuit, and the signal input end of the height detection circuit is electrically connected with the signal output end of the dust detection circuit; the wireless receiving circuit comprises a stabilized voltage power supply and a trigger sub-circuit, and the power supply output end of the stabilized voltage power supply is electrically connected with the power supply input end of the trigger sub-circuit.

2. The intelligent safety helmet for tunnel construction as claimed in claim 1, wherein the gas detection circuit comprises a gas-sensitive device, a resistor, an adjustable resistor, a diode, a relay, a buzzer and an NPN transistor, which are electrically connected with each other, a first measuring electrode of the gas-sensitive device is connected with one end of the resistor, a positive electrode of the relay and a control power input end, the other end of the resistor is connected with a positive power input end of the gas-sensitive device, a negative power input end of the gas-sensitive device is connected with a negative electrode of the diode, a negative power input end of the buzzer and an emitter of the NPN transistor, a positive electrode of the diode is connected with one end of the first adjustable resistor, the other end of the first adjustable resistor is connected with one end of the second adjustable resistor and a second measuring electrode of the gas-sensitive device, the other end of the second adjustable resistor is connected with a base of the NPN transistor, and a collector, the normally open contact end of the relay is connected with the positive power supply input end of the sounder.

3. The intelligent safety helmet for tunnel construction as claimed in claim 1, wherein the height detection circuit comprises a photoelectric switch and a vibration motor electrically connected to each other, a negative power input terminal of the photoelectric switch is connected to a negative power input terminal of the vibration motor, and a power output terminal of the photoelectric switch is connected to a positive power input terminal of the vibration motor.

4. The intelligent safety helmet for tunnel construction according to claim 1, wherein the dust detection circuit comprises a photodiode and a phototransistor, a resistor, an adjustable resistor, a diode, an electrolytic capacitor, an NPN transistor electrically connected therebetween, wherein a positive electrode of the photodiode is connected to one end of the first adjustable resistor and a collector of the first NPN transistor, a negative electrode of the photodiode is connected to the collector of the phototransistor and one end of the first resistor, the other end of the first resistor is connected to one end of the second adjustable resistor, an emitter of the phototransistor is connected to one end of the second resistor and a positive electrode of the diode, a negative electrode of the diode is connected to one end of the third resistor, the other end of the third resistor is connected to a base of the second NPN transistor, the collector of the second NPN transistor is connected to the other end of the first adjustable resistor, a sliding contact of the first adjustable resistor is connected to the base of the first NPN transistor, the emitter of the first NPN triode is connected with the anode of the electrolytic capacitor, and the other end of the second resistor, the other end of the second adjustable resistor, the cathode of the electrolytic capacitor and the emitter of the second NPN triode are connected.

5. The intelligent safety helmet for tunnel construction as claimed in claim 1, wherein the wireless transmitting circuit is a wireless transmitting circuit module, and two contacts of one of the wireless transmitting key buttons of the wireless transmitting circuit module are electrically connected together.

6. The intelligent safety helmet for tunnel construction according to claim 1, wherein the voltage-stabilized power supply of the wireless receiving circuit is an AC-to-DC switching power supply module; the trigger sub-circuit comprises a wireless receiving circuit module, a resistor, an NPN triode and a buzzer, wherein the wireless receiving circuit module is electrically connected with the resistor, the positive power supply input end of the wireless receiving circuit module is connected with the positive power supply input end of the buzzer and the positive power supply output end of the stabilized voltage power supply, the negative power supply output end of the stabilized voltage power supply is connected with the emitting electrode of the NPN triode and the negative power supply input end of the wireless receiving circuit module, the collecting electrode of the NPN triode is connected with the negative power supply input end of the buzzer, the output end of the wireless receiving circuit module is connected with one end of the resistor.

7. The intelligent safety helmet for tunnel construction as claimed in claim 1, wherein the temperature detection circuit comprises a temperature switch and a buzzer, which are electrically connected, and one end of the temperature switch is connected with the positive power input end of the buzzer.

Technical Field

The invention relates to the technical field of safety equipment, in particular to an intelligent safety helmet for tunnel construction.

Background

With the rapid development of national economy, tunnel construction in China is more and more diverse. The highway, the railway tunnel and the like improve the technical indexes of the route, shorten the distance and the driving time and improve the operation benefit. The tunnel construction is limited by factors such as construction conditions, environment and the like, and the existing tunnel construction has the defects of complex construction management, multiple potential safety hazards and severe construction conditions, and is always a management difficulty in the current tunnel engineering. Especially, in the construction of mountainous area tunnels, not only dust can influence the health of workers in the construction, but also the personal safety of constructors can be threatened due to the leakage probability of combustible gas such as gas and the like.

In order to prevent the gas leakage from affecting the safety of constructors, a gas detector is arranged in a tunnel in the prior art, and when the gas leakage in the tunnel is detected, an alarm signal is generated to prompt the constructors to evacuate from the site in time. Although the mode has a certain safety effect, the gas detector has a fixed installation position and a limited detection area, so that in practical application, gas leakage is probably not generated at the detection position, and gas leakage is generated at other undetected points, thereby further causing gas poisoning of constructors. At present, dust control in tunnel construction generally means that when dust exceeds standard obviously and visually appears in a tunnel, workers open spraying equipment and the like to perform dust falling treatment; in the control mode, because the tunnel construction surfaces are more, related personnel cannot perform dust inspection on each construction area in real time, and the health of the constructors cannot be guaranteed. In addition, particularly in the operation in the hot summer, when the temperature is high, the heat of the constructors is possibly caused, and the health of the constructors is influenced. Finally, in tunnel construction, due to the fact that the operation surface is narrow, a constructor can collide the operation surface or other construction equipment with the head safety helmet carelessly, and when the collision force is too large, the head of the constructor and other positions of the constructor can be damaged with probability.

Disclosure of Invention

In order to overcome the defects that the personal safety of constructors at each point in a tunnel cannot be effectively ensured due to the structural limitation of the gas detector applied in the prior tunnel construction, related personnel cannot detect dust in the tunnel in real time, the health of the constructors is affected, the constructors are easy to collide with foreign matters to be injured when working heads in the tunnel, and the heatstroke probability of the working temperature cannot be known, the invention provides a safety helmet body, wherein a gas detection circuit, a dust detection circuit, a height detection circuit, a temperature detection circuit and the like are arranged on the safety helmet body, each constructor wears the safety helmet body to operate in the application, when the gas leakage and the dust exceeding the standard occur at the nearby tunnel working point, different warning signals can be sent out at the first time to prompt the constructors to timely evacuate from the site, and when the temperature exceeds the standard, the constructors can be prompted to temporarily stop the operation to prevent heatstroke, when the head of a constructor is close to the top operation surface of a head or other construction equipment for a certain distance in operation, the intelligent safety helmet can prompt the constructor to pay attention to safety in time, and can inform management indoor personnel to take corresponding measures in time when Waxi leakage occurs, so that the intelligent safety helmet can play a good protection role for the constructor during tunnel construction.

The technical scheme adopted by the invention for solving the technical problems is as follows:

an intelligent safety helmet for tunnel construction comprises a safety helmet body, a storage battery, a power switch and a charging socket; it is characterized by also comprising a gas detection circuit, a dust detection circuit, a height detection circuit, a wireless transmitting circuit, a wireless receiving circuit and a temperature detection circuit; the upper end of the safety helmet body is provided with a shell, and the storage battery, the power switch, the charging socket, the gas detection circuit, the dust detection circuit, the height detection circuit, the wireless transmitting circuit and the temperature detection circuit are arranged in the shell; the wireless receiving circuit is installed in a management room near a construction area; the storage battery is electrically connected with the two ends of the power supply input of the gas detection circuit, the dust detection circuit, the height detection circuit and the temperature detection circuit respectively; the power supply output end of the gas detection circuit is electrically connected with the power supply input end of the wireless transmitting circuit, and the signal input end of the height detection circuit is electrically connected with the signal output end of the dust detection circuit; the wireless receiving circuit comprises a stabilized voltage power supply and a trigger sub-circuit, and the power supply output end of the stabilized voltage power supply is electrically connected with the power supply input end of the trigger sub-circuit.

Furthermore, the gas detection circuit comprises a gas sensitive device, a resistor, an adjustable resistor, a diode, a relay, a buzzer and an NPN triode, the gas sensor is electrically connected with the gas sensor, a first measuring electrode of the gas sensor is connected with one end of a resistor, a positive electrode of a relay and an input end of a control power supply, the other end of the resistor is connected with a positive power supply input end of the gas sensor, a negative power supply input end of the gas sensor is connected with a negative electrode of a diode, a negative power supply input end of a sounder and an emitting electrode of an NPN triode, a positive electrode of the diode is connected with one end of a first adjustable resistor, the other end of the first adjustable resistor is connected with one end of a second adjustable resistor and a second measuring electrode of the gas sensor, the other end of the second adjustable resistor is connected with a base electrode of the NPN triode, a collector electrode of the NPN triode is connected with a negative.

Furthermore, the height detection circuit comprises a photoelectric switch and a vibration motor which are electrically connected, wherein a negative power supply input end of the photoelectric switch is connected with a negative power supply input end of the vibration motor, and a power supply output end of the photoelectric switch is connected with a positive power supply input end of the vibration motor.

Further, the dust detection circuit comprises a photodiode, a phototriode, a resistor, an adjustable resistor, a diode, an electrolytic capacitor and an NPN triode which are electrically connected with each other, wherein the anode of the photodiode is connected with one end of a first adjustable resistor and the collector of the first NPN triode, the cathode of the photodiode is connected with the collector of the phototriode and one end of the first resistor, the other end of the first resistor is connected with one end of a second adjustable resistor, the emitter of the phototriode is connected with one end of the second resistor and the anode of the diode, the cathode of the diode is connected with one end of a third resistor, the other end of the third resistor is connected with the base of the second NPN triode, the collector of the second NPN triode is connected with the other end of the first adjustable resistor, the sliding contact end of the first adjustable resistor is connected with the base of the first NPN triode, the emitter of the first NPN triode is connected with the anode of the electrolytic, the other end of the second resistor, the other end of the second adjustable resistor, the cathode of the electrolytic capacitor and the emitter of the second NPN triode are connected.

Furthermore, the wireless transmitting circuit is a wireless transmitting circuit module, and two contacts under one of the wireless transmitting key of the wireless transmitting circuit module are electrically connected together.

Furthermore, the stabilized voltage power supply of the wireless receiving circuit is an alternating current to direct current switching power supply module; the trigger sub-circuit comprises a wireless receiving circuit module, a resistor, an NPN triode and a buzzer, wherein the wireless receiving circuit module is electrically connected with the resistor, the positive power supply input end of the wireless receiving circuit module is connected with the positive power supply input end of the buzzer and the positive power supply output end of the stabilized voltage power supply, the negative power supply output end of the stabilized voltage power supply is connected with the emitting electrode of the NPN triode and the negative power supply input end of the wireless receiving circuit module, the collecting electrode of the NPN triode is connected with the negative power supply input end of the buzzer, the output end of the wireless receiving circuit module is connected with one end of the resistor.

Furthermore, the temperature detection circuit comprises a temperature switch and a buzzer, wherein the temperature switch and the buzzer are electrically connected, and one end of the temperature switch is connected with the positive power supply input end of the buzzer.

The invention has the beneficial effects that: in the application of the invention, each constructor wears a safety helmet body to operate. During operation, when gas leakage occurs at the operation point position of a constructor, the gas leakage is detected by a gas detection circuit, and dust exceeding the standard is detected by a dust detection circuit; and then gas detection circuit detection can send out loud alarm sound and remind the operating personnel to withdraw from the scene in time, vibrating motor sends out vibration suggestion constructor operation position dust exceeds standard and can suspend the operation (follow-up relevant personnel carry out water spray dust fall processing to the operation position etc.), because, the mode that gas exceeds standard and dust exceeds standard suggestion is different, constructor can carry out corresponding action according to different alarm information like this, if gas exceeds standard withdraw outside the tunnel at once, the dust exceeds standard and can just wait for relevant personnel dust fall processing in the area that the dust does not exceed standard in the tunnel and do business again, brought the facility for constructor. In the height detection circuit, when the upper end of the head of a constructor is close to a head top operation surface or other construction equipment for a certain distance, the vibration of the vibration motor can prompt the constructor to pay attention to safety in time, and the constructor does not collide the head, so that a good safety protection effect is achieved. When the temperature in the tunnel exceeds 40 ℃ (in hot summer), the buzzer of the temperature detection circuit can make a loud prompt sound, and workers can stop working temporarily after hearing the sound, so that heatstroke and the like are effectively prevented. In the invention, when gas leakage occurs, the wireless transmitting circuit and the wireless receiving circuit can inform management indoor personnel of taking corresponding measures in time, for example, all personnel in the tunnel are informed to evacuate as soon as possible, emergency exhaust equipment in the tunnel is opened, gas in the tunnel is discharged, spraying equipment is opened to dilute gas, and the like, so that the gas leakage protection device can play a good protection role for constructors. Based on the above, the invention has good application prospect.

Drawings

The invention is further illustrated with reference to the following figures and examples.

FIG. 1 is an enlarged view of the whole and a part of the present invention.

Fig. 2 and 3 are circuit diagrams of the present invention.

Detailed Description

As shown in fig. 1, an intelligent safety helmet for tunnel construction includes a safety helmet body 1, a storage battery 2, a power switch 3, and a charging socket 4; the device is also provided with a gas detection circuit 5, a dust detection circuit 6, a height detection circuit 7, a wireless transmitting circuit 8, a wireless receiving circuit and a temperature detection circuit 11; a shell 101 which is integrally formed with the safety helmet body and is consistent with the arc shape of the upper end of the safety helmet body is arranged outside the upper end of the safety helmet body 1, the storage battery 2, the power switch 3, the charging socket 4, the gas detection circuit 5, the dust detection circuit 6, the height detection circuit 7, the wireless transmitting circuit 8 and the temperature detection circuit 11 are arranged on a circuit board, and the circuit board is arranged in the shell 1; the wireless receiving circuit is arranged on a circuit board in the element box 10, and the element box 10 is arranged in a management room near a construction area; the wireless receiving circuit includes a voltage-stabilized power supply 91 and a trigger sub-circuit 92.

As shown in fig. 1, 2 and 3, the storage battery G is a 12V/2Ah sheet lithium storage battery, the power switch S is a toggle power switch, the charging socket CZ is a coaxial power socket, and the handle of the power switch S and the jack of the charging socket CZ are positioned outside two openings in the upper end of the shell. The gas detection circuit comprises a gas sensitive device A with a model number QM-N5, a resistor R, adjustable resistors RP and RP1, a diode VD, a relay K and a buzzer B, NPN and a triode Q1 which are connected through circuit board wiring, wherein the first measuring pole 3 of the gas sensitive device A is connected with one end of the resistor R, the anode of the relay K and the input end of a control power supply, the other end of the resistor R is connected with the anode power supply input end 1 of the gas sensitive device A, the cathode power supply input end 2 of the gas sensitive device A is connected with the cathode of the diode VD, the cathode power supply input end of the buzzer B and the emitter of an NPN triode Q1, the anode of the diode VD is connected with one end of a first adjustable resistor RP, the other end of the first adjustable resistor RP is connected with one end of a second adjustable resistor RP1 and the second measuring pole 4 of the gas sensitive device A, the other end of a second adjustable resistor RP1 is connected with the base of the NPN triode Q1, the collector of the triode, the normally open contact end of the relay K is connected with the positive power supply input end of the annunciator B; the front end of the probe of the gas sensitive device 51 is positioned outside the third opening at the front end of the shell 101 (the circular metal net is protected before the opening, and the circular metal net is heated and fixedly arranged before the opening). The height detection circuit comprises a photoelectric switch A2 (71), a vibrating micro motor M (the vibrating micro motor 72 is formed by installing an eccentric wheel in front of a 12V and 2W direct current motor and is consistent with the structure of a mobile phone vibrating motor), the vibrating micro motor M is connected with the circuit board through wiring, a pin 2 of a negative power supply input end of a photoelectric switch A2 is connected with a negative power supply input end of the vibrating motor M, a pin 3 of a power supply output end of a photoelectric switch A2 is connected with a positive power supply input end of the vibrating motor M, and a detection head of the photoelectric switch 71 is vertically positioned outside a fourth opening in the middle of the upper end of the shell 101 (beneficial; the photoelectric switch A2 is a PNP type remote square shell infrared reflection photoelectric switch finished product (small-sized) with model number E3Z-D62, each has three connecting wires, two of which are power input wires 1 and 2, the other is a signal output wire 3, the upper end of the photoelectric detection switch is provided with a detection head, the emission head of the detection head can linearly emit infrared light during working, when the infrared light emitted by the detection head is blocked by an object in the farthest 60 cm range and is received by a receiving head of the detection head, the output wire 3 can output high level, an adjusting knob is arranged in the lower end of the shell of the photoelectric detection switch, the adjusting knob adjusts the detection distance of the detection head to the left and adjusts the detection distance of the detection head to the right (the detection distance is 30cm after adjustment).

As shown in fig. 1, 2 and 3, the dust detection circuit includes a photodiode VD1 and a phototransistor Q5, resistors R1, R2 and R3, adjustable resistors RP2 and RP3, a diode VD2, an electrolytic capacitor C2, NPN triodes Q3 and Q4, which are connected by wiring on a circuit board, the photodiode VD1 (61) and the phototransistor Q5(62) are face-to-face welded on the circuit board at an interval of about 3cm, an emitter of the photodiode VD1 and a receiving surface of the phototransistor Q5 are in a face-to-face state, a fifth opening is formed in the front end of the housing (the opening is protected by a circular metal net, the circular metal net is heated and fixedly installed in front of the opening), and the photodiode VD2 and the phototransistor Q5 are located at the rear side of the opening; the positive electrode of a photodiode VD1 is connected with one end of a first adjustable resistor RP3 and the collector of a first NPN triode Q4, the negative electrode of the photodiode VD1 is connected with the collector of a phototriode Q5 and one end of a first resistor R2, the other end of the first resistor R2 is connected with one end of a second adjustable resistor RP2, the emitter of the phototriode Q5 is connected with one end of a second resistor R1 and the positive electrode of a diode VD2, the negative electrode of the diode VD2 is connected with one end of a third resistor R3, the other end of the third resistor R3 is connected with the base of a second NPN triode Q3, the collector of the second NPN triode Q3 is connected with the other end of a first adjustable resistor RP3, the sliding contact end of the first adjustable resistor RP3 is connected with the base of a first NPN triode Q4, the emitter of the first NPN triode Q4 is connected with the positive electrode of an electrolytic capacitor C2, the other end of a second resistor R1, the other end of the second adjustable resistor RP 53, the, The emitter of the second NPN transistor Q3 is connected. The wireless transmitting circuit A3 is a finished product of a wireless transmitting circuit with model ZYO1500-A72, the transmitting distance of wireless signals is 1500 meters, and two contacts under a first wireless transmitting key S1 of a wireless transmitting circuit module are connected together through a lead. The temperature detection circuit comprises a temperature switch and a buzzer B2 which are connected through a circuit board in a wiring mode, and one end of the temperature switch W is connected with the positive power supply input end of the buzzer B2.

As shown in fig. 1, 2 and 3, the regulated power supply a4 of the wireless receiving circuit is a finished product of a 220V/5V/100W ac-220V-to-dc 5V switching power supply module; the trigger sub-circuit comprises a wireless receiving circuit module A5, a resistor R5, an NPN triode Q6 and a sounder B1 of model ZYO-1500-A72, which are connected through circuit board wiring, a pin 1 at the positive power input end of the wireless receiving circuit module A5 is connected with a pin 3 at the positive power input end of the sounder B1 and a pin 3 at the positive power output end of a stabilized power supply A4, a pin 4 at the negative power output end of the stabilized power supply A4 is connected with an emitter of the NPN triode Q6 and a pin 3 at the negative power input end of the wireless receiving circuit module A5, a collector of the NPN triode Q6 is connected with a negative power input end of the sounder B1, a pin 4 at the output end of the wireless receiving circuit module A5 is connected with one end of the resistor R5, and the.

As shown in fig. 1, 2 and 3, two poles of the storage battery G and two terminals of the charging socket CZ are respectively connected through leads (when the storage battery G is out of power, an external 12V power charger plug can be inserted into the charging socket CZ to charge the storage battery G). The positive pole of the storage battery G is connected with one end of the power switch S through a lead. The other end of the power switch S, the cathode of the storage battery G, one end of a resistor R and the cathode of a diode VD at the power input ends of the gas detection circuit, the anode of a photodiode VD1 and the other end of a resistor R1 at the power input ends of the dust detection circuit, pins 1 and 2 of a photoelectric switch A2 at the power input ends of the height detection circuit, the other end of a temperature switch W at the power input ends of the temperature detection circuit and the power input end of the cathode of a buzzer B2 are respectively connected through wires. The power output end relay K normally open contact end of the gas detection circuit, the emitting electrode of the NPN triode Q1 and the power input end VCC and GND of the wireless transmitting circuit A3 are respectively connected through leads. The signal input end of the height detection circuit is connected with the positive power supply input end of the vibrating motor M and the signal output end NPN triode Q4 emitter of the dust detection circuit through leads. The wireless receiving circuit comprises a stabilized voltage power supply and a trigger sub-circuit, wherein the power input end 1 and the power input end 2 of the stabilized voltage power supply A4 are respectively connected with the two poles of an alternating current 220V power supply through leads (a power plug is inserted into a commercial power socket). The power supply output end of the voltage-stabilized power supply A4, the power supply input end of the trigger sub-circuit, the positive power supply input end of the buzzer B1 and the emitter of the NPN triode Q6 are respectively connected through leads.

As shown in fig. 1, 2 and 3, after the 220V ac power supply enters pins 1 and 2 of regulated power supply a4, regulated power supply a4 outputs stable 5V dc power supply to the power input terminal of the trigger sub-circuit under the action of its internal circuit, so that the trigger sub-circuit is in an energized state. In the invention, each tunnel constructor wears a certain safety helmet body 1 to operate, and turns on a power switch S before entering the tunnel, so that the gas detection circuit, the dust detection circuit, the height detection circuit and the temperature detection circuit are all in an electrified working state. In the gas detection circuit, after the gas sensitive device A works with electricity (the resistor R is used for reducing voltage and limiting current of the gas sensitive device A to prevent the working voltage and current of the gas sensitive device A from being overhigh), when no gas leaks from a working point position, the internal resistance between the first measuring electrode 3 pin and the second measuring electrode 4 pin of the gas sensitive device is large, therefore, the 4 pins of the gas sensitive device A are reduced in voltage and limited by the adjustable resistor RP, the voltage of the diode VD is unidirectionally conducted, the voltage is low, the voltage is reduced and limited by the adjustable resistor RP1 and then enters the base electrode of the NPN triode Q1 to be lower than 0.7V, the NPN triode Q1 is in a cut-off state, then the rear-stage buzzer B cannot sound with electricity, and constructors work normally. When the gas-sensitive device A is powered on and gas leakage occurs at the periphery of an operation point, at the moment, under the action of an internal mechanism of the gas-sensitive device A, the internal resistance between the pin 3 of the first measuring electrode and the pin 4 of the second measuring electrode rapidly drops, the pin 4 of the gas-sensitive device A increases to the ground voltage, the voltage is reduced and limited through the adjustable resistor RP1, the voltage is then sent to the base of the NPN triode Q1 and is higher than 0.7V, then the NPN triode Q1 conducts the collector of the NPN triode Q26 to output low level to be sent to the negative power input end of the relay K, the relay K is powered on and attracts the control power input end and the normally open contact. Because the normally open contact end of the relay K is connected with the audible device B and the positive power supply input end VCC of the wireless transmitting circuit module A3 (the wireless transmitting circuit module A3 is electrified), the audible device B can send out a loud prompt sound at this moment to prompt operators and persons nearby hearing the audible device B to sound, the operation points are leaked with gas, and the operators are evacuated from the site to the outside of the tunnel immediately, so that serious personal injury accidents are avoided (the audible device B cannot be powered off and cannot sound any more until the operators leave the gas leakage area or close a power supply switch). Because two contacts under the first wireless transmitting key S1 of the wireless transmitting circuit module A3 are connected together through a conducting wire, gas leakage at an operation point occurs, and after the wireless transmitting circuit module A3 is powered on, the wireless transmitting circuit module A3 can transmit a first path of wireless closing signal. In practical situations, after a wireless transmitting circuit module A3 at any construction point in a tunnel transmits a first wireless closing signal, a wireless transmitting circuit module and a wireless receiving circuit module with longer wireless communication receiving and transmitting distances can be adopted within a range of 1500 meters (if the tunnel is long, a wireless transmitting circuit module and a wireless receiving circuit module with longer wireless communication receiving and transmitting distances can be adopted to meet practical requirements), after the wireless receiving circuit module a5 receives the first wireless closing signal, 4 pins (in the embodiment, 2, 5, 6 and 7 pins of the wireless receiving circuit module a5 are suspended) of the wireless receiving circuit module a5 output high levels, the high levels are subjected to voltage reduction and current limitation through a resistor R5 and enter a base of an NPN triode Q6, then the NPN triode Q6 is conducted with a collector to output low levels and enters a negative power supply input end of a buzzer B1, the buzzer B1 is powered to emit a loud prompt sound to prompt management indoor personnel to take measures in time, for example, all the people in the tunnel are informed to evacuate as soon as possible, emergency exhaust equipment in the tunnel is opened, gas in the tunnel is discharged, spraying equipment is opened to dilute the gas, and the like, so that the protective effect on constructors can be achieved.

As shown in fig. 1, 2 and 3, in the dust detection circuit, a photodiode VD1 and a phototransistor Q5 are in a series connection state; after the dust detection circuit works by electrifying, infrared light emitted by the photodiode VD1 is irradiated on the light receiving surface of the phototriode Q5, the internal resistance of the phototriode Q5 is reduced by the irradiation of light, so that the current of a series circuit formed by the photodiode VD1 and the phototriode Q5 is increased, the current flows through the photodiode VD1 to increase the luminous intensity of the phototriode Q5, and then is irradiated on the light receiving surface of the phototriode Q5, so that the internal resistance of the phototriode Q5 is reduced, a strong positive feedback process is formed in a circulating mode, the current of the series circuit rises to the maximum value, and the photodiode VD1 is in the maximum power state, and a better detection effect is achieved; at this time, the voltage drop generated by the load resistor R1 is unidirectionally conducted through the diode VD2 to enter the base of the NPN transistor Q3 (higher than 0.7V, the resistor R3 steps down the current), so that the NPN transistor Q3 turns on its collector to output a low level to enter the base of the NPN transistor Q4, and the base of the NPN transistor Q4 is not properly biased forward and is cut off, so that the vibration motor M cannot be electrically operated. When the dust at the operation point is more, the dust can block infrared light emitted by the photodiode VD1, and the light transmittance of air is poor (the light flux of the photodiode VD1 is reduced), so that the infrared light irradiated by the photodiode VD1 on the light receiving surface of the phototriode Q5 is reduced, the internal resistance of the light receiving surface of the phototriode Q5 is increased due to the weakened infrared light, the current of a series loop formed by the photodiode VD1 is reduced, and a negative feedback process is formed in such a circulating mode, and finally the current of the photodiode VD1 is stabilized at an initial current value; at the moment, the voltage drop on the resistor R1 is reduced (lower than 1.2V), the base voltage entering the NPN triode Q3 is reduced to be lower than 0.7V through the unidirectional conduction of the diode VD and the voltage reduction and current limiting of the resistor R3, so that the collector of the NPN triode Q3 is cut off and no low level is output to enter the base of the NPN triode Q4; the base of NPN transistor Q4 gets properly forward biased conduction from the positive pole of the 12V power supply via the sliding contact terminal of adjustable resistor RP 3. After the NPN triode Q4 is conducted, the emitter of the NPN triode Q4 outputs high level to enter the positive power supply input end of the vibration motor M (the electrolytic capacitor C2 has a filtering effect), so that the vibration motor M is electrified to vibrate, and after the head of an operator is prompted by vibration, the operator can visually know that the dust on site exceeds the standard (or the head is prompted to approach the top operation surface of the head or other construction equipment for a certain distance), and the vibration motor M cannot lose power and does not work until the operator leaves the dust site exceeding the standard or closes a power switch; and dust-exceeding constructors can wait for dust fall treatment and operation of related personnel in the area where dust does not exceed the standard in the tunnel, so that convenience is brought to the constructors. The resistor R1 and the adjustable resistor RP2 are positive feedback control resistors, the resistance value of the adjustable resistor RP2 needs to be determined during production, the device is placed in a room with dust (the dust amount is a threshold point of subsequent product alarm, and a tester wears a mask), and then the resistance value of the adjustable resistor RP2 is slowly adjusted, so that the current flowing through the photodiode VD1 just generates negative feedback effect, and the vibration motor just obtains electricity to generate vibration, and in subsequent practical application, when the dust amount on site exceeds the standard, the vibration motor M can obtain electricity to work. After the determination, the technician measures the resistance value of the adjustable resistor RP2 at this time, and the subsequent batch production directly adjusts the resistance value of the adjustable resistor RP2 to the right position, or replaces the fixed resistor with the same resistance value, and does not determine the resistance value any more.

As shown in fig. 1, 2, and 3, in the height detection circuit, when the upper end of the helmet body 1 at the top of the head of the worker is spaced from the tunnel working surface or other construction equipment by a certain distance or more (for example, greater than 30cm, the specific height can be set by adjusting the knob of the photoelectric switch a 2), the 3 feet of the photoelectric switch a2 do not output high level, and the vibration motor M does not work electrically. In actual construction, when the upper end of the helmet body 1 at the top of an operator is spaced below a certain distance (for example, less than 30cm) from a tunnel working face or other construction equipment, the 3 feet of the photoelectric switch A2 can output high level to enter the positive power input end of the vibration motor M, so that the vibration motor M is electrified to vibrate, and after the head of the operator is prompted by vibration, the operator can intuitively know that the distance between the head and the working face or other construction equipment is too short (or the site dust exceeds the standard, in actual conditions, the operator can immediately judge the vibration prompt of the vibration motor M in high-level operation because the distance between the head and the working face or other construction equipment is too short, and if earth excavation, concrete pouring and the like are carried out, the dust exceeds the standard, or the distance between the working face and other construction equipment is too short, not big like harm that gas leakage brought, constructor can have the reaction of certain time, so this embodiment adopts same vibrating motor suggestion constructor dust to exceed standard and the head contacts other objects too closely), arouses constructor's alert, prevents that the head from colliding overhead working face or other construction equipment and causing the injury. In the temperature detection circuit, when the operating point position in the tunnel is lower than 40 ℃, the internal contact of the temperature switch W is open-circuited, and then the buzzer B2 cannot be electrified to work, which represents that the temperature in the tunnel is proper at the moment. When the operating point in the tunnel is higher than 40 ℃, the internal contact of the temperature switch W is closed, so that a 12V power supply can enter the positive power supply input end of the buzzer B2, the buzzer B2 can sound electrically, the temperature in the tunnel is over-temperature at the moment, and thus, a worker can hear the sound of the buzzer B2 and then temporarily leave the tunnel to prevent heatstroke and continue construction after the temperature in the tunnel is proper (the sound of the buzzer B2 is droplet sound, which is different from the buzzer B, and the worker effectively distinguishes the droplet sound). In fig. 2 and 3, the resistances R, R1, R2, R3 and R5 are 47 Ω, 220 Ω, 1K, 30K and 1K, respectively; the specifications of the adjustable resistors RP, RP1, RP2 and RP3 are 2.2K, 20K, 4.7K and 4.7K respectively; NPN triodes Q1, Q3, Q4 and Q6 are respectively 9013, 9014 and 9013; the models of the diodes VD and VD2 are respectively 1N4001 and 1N 4148; relay K is a DC12V relay; the model of the electrolytic capacitor C2 is 4.7 mu F/25V; the signal sounders B (working voltage 12V) and B1 (working voltage 5V) are type SFM-27 active continuous signal sounders finished products; photodiode VD1 model BT 401; the phototriode Q5 is a finished product of a phototriode with the model number of 3DU 4; the buzzer B2 is a miniature buzzer finished product with the model TMB12A 12; the temperature switch is a sheet-shaped 40 ℃ kick type normally open contact temperature switch.

While there have been shown and described what are at present considered the fundamental principles and essential features of the invention and its advantages, it will be apparent to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, but is capable of other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

Furthermore, it should be understood that although the present description refers to embodiments, the embodiments do not include only one independent technical solution, and such description is only for clarity, and those skilled in the art should take the description as a whole, and the technical solutions in the embodiments may be appropriately combined to form other embodiments that can be understood by those skilled in the art.