CN115311810A

CN115311810A - Infrared fire source early warning detection system

Info

Publication number: CN115311810A
Application number: CN202210940117.2A
Authority: CN
Inventors: 陈涛; 郭洁; 王翔
Original assignee: Dalai Nur Coal Industry Co Ltd
Current assignee: Dalai Nur Coal Industry Co Ltd
Priority date: 2022-08-05
Filing date: 2022-08-05
Publication date: 2022-11-08
Anticipated expiration: 2042-08-05
Also published as: CN115311810B

Abstract

The utility model provides an infrared ray fire source early warning detection system, includes: the detection end of the infrared sensing unit detects infrared rays radiated by a fire source; the modulation end of the modulation unit is arranged between the detection end of the infrared sensing unit and the fire source; the input end of the phase-sensitive detection unit is electrically connected with the output end of the infrared sensing unit and the output end of the modulation unit; and the output end of the phase-sensitive detection unit is electrically connected with the input end of the display unit. In the infrared fire source early warning and detecting system, the mode of carrying out the fire early warning through the infrared ray that detects the fire source radiation makes the operation personnel can in time judge the emergence of conflagration to make the conflagration eliminated among the bud, avoided great life and loss of property, effectively improved the security of production.

Description

Infrared fire source early warning detection system

Technical Field

The utility model relates to a fire source early warning technical field especially relates to an infrared ray fire source early warning detection system.

Background

The fire disaster is a great hidden trouble in production, and timely finding and processing are important means for avoiding fire disaster spreading, but the fire disaster is mostly in a larger state when the fire disaster is detected by the conventional fire disaster detection device, the larger fire disaster is difficult to be eliminated in time, and particularly in the fields of coal and the like, the larger life and property losses are easily caused.

Disclosure of Invention

The present disclosure is directed to solving, at least to some extent, one of the technical problems in the related art.

Therefore, the purpose of the present disclosure is to provide an infrared fire source early warning detection system.

In order to achieve the above object, the present disclosure provides an infrared fire source early warning detection system, including: the detection end of the infrared sensing unit detects infrared rays radiated by the fire source; the modulation end of the modulation unit is arranged between the detection end of the infrared sensing unit and the fire source; the input end of the phase-sensitive detection unit is electrically connected with the output end of the infrared sensing unit and the output end of the modulation unit; and the output end of the phase-sensitive detection unit is electrically connected with the input end of the display unit, and the phase-sensitive detection unit outputs a signal to the display unit according to a comparison result of the output signal of the infrared sensing unit and the output signal of the modulation unit so as to enable the display unit to display the temperature of the fire source.

Optionally, the infrared sensing unit includes: a thermistor that detects infrared rays radiated from the fire source; the first end of the compensation resistor is connected with the first end of the thermistor; the positive electrode of the first power supply is connected with the second end of the thermistor, and the negative electrode of the first power supply is grounded; and the anode of the second power supply is connected with the cathode of the first power supply, and the cathode of the second power supply is connected with the second end of the compensation resistor.

Optionally, the early warning detection system further includes: an optical unit, the optical unit comprising: the fire source comprises a convex lens and a flat mirror, wherein the convex lens is arranged between the fire source and the thermistor, the focus of the convex lens is positioned on the thermistor, the flat mirror is arranged between the convex lens and the fire source, and the flat mirror is made of a zinc sulfide material.

Optionally, the early warning detection system further includes: the input end of the first amplifying unit is electrically connected with the output end of the infrared sensing unit; and the input end of the second amplifying unit is electrically connected with the output end of the first amplifying unit, and the output end of the second amplifying unit is connected with the input end of the phase-sensitive detection unit.

Optionally, the first amplifying unit includes: a third power supply, a negative electrode of the third power supply being grounded; a tenth resistor, a second end of the tenth resistor being connected to the positive electrode of the third power supply; a first end of the fifth capacitor is connected with a first end of the tenth resistor, and a second end of the fifth capacitor is grounded; the first end of the first capacitor is connected with the output end of the infrared sensing unit; a first end of the first resistor is connected with a first end of the tenth resistor; a first end of the second resistor is connected with a second end of the first resistor, and a second end of the second resistor is connected with a negative electrode of the third power supply; a first end of the third resistor is connected with the second end of the first capacitor, and a second end of the third resistor is connected with the first end of the second resistor; the base electrode of the first triode is connected with the first end of the third resistor, and the collector electrode of the first triode is connected with the first end of the tenth resistor; a first end of the fourth resistor is connected with an emitting electrode of the first triode, and a second end of the fourth resistor is connected with a negative electrode of the third power supply; a first end of the second capacitor is connected with a first end of the second resistor, and a second end of the second capacitor is connected with an emitting electrode of the first triode; a first end of the third capacitor is connected with a second end of the second capacitor; a first end of the sixth resistor is connected with a second end of the third capacitor, and a second end of the sixth resistor is connected with a negative electrode of the third power supply; a first end of the fifth resistor is connected with a first end of the tenth resistor, and a second end of the fifth resistor is connected with a second end of the third capacitor; a first end of the seventh resistor is connected with a first end of the tenth resistor; the base electrode of the second triode is connected with the second end of the fifth resistor, and the collector electrode of the second triode is connected with the second end of the seventh resistor; a first end of the eighth resistor is connected with an emitting electrode of the second triode, and a second end of the eighth resistor is connected with a negative electrode of the third power supply; a first end of the fourth capacitor is connected with the emitter of the second triode, and a second end of the fourth capacitor is connected with the negative electrode of the third power supply; a third triode, wherein the base of the third triode is connected with the second end of the seventh resistor, and the collector of the third triode is connected with the first end of the tenth resistor; and a first end of the ninth resistor is connected with the emitter of the third triode, and a second end of the ninth resistor is connected with the negative electrode of the third power supply.

Optionally, the second amplifying unit includes: a first end of the eleventh resistor is connected with a first end of the tenth resistor; the first end of the attenuator is connected with the emitter of the third triode, and the third end of the attenuator is connected with the second end of the eleventh resistor; a first end of the twelfth resistor is connected with the fourth end of the attenuator, and a second end of the twelfth resistor is connected with the negative electrode of the third power supply; a twenty-first resistor, wherein a first end of the twenty-first resistor is connected to a second end of the tenth resistor, and a second end of the twenty-first resistor is connected to a positive electrode of the third power supply; a first end of the eleventh capacitor is connected with a first end of the twenty-first resistor, and a second end of the eleventh capacitor is grounded; a thirteenth resistor, a first end of the thirteenth resistor being connected to a first end of the twenty-first resistor; a fourth triode, wherein the base of the fourth triode is connected with the second end of the attenuator, and the collector of the fourth triode is connected with the second end of the thirteenth resistor; a fourteenth resistor, a first end of which is connected to the emitter of the fourth transistor, and a second end of which is connected to the cathode of the third power supply; a first end of the sixth capacitor is connected with an emitting electrode of the fourth triode, and a second end of the sixth capacitor is connected with a negative electrode of the third power supply; a first end of the seventh capacitor is connected with the second end of the thirteenth resistor; a seventeenth resistor, a first end of the seventeenth resistor being connected to a first end of the twenty-first resistor; a fifth triode, wherein the fifth triode is of an NPN type, a base of the fifth triode is connected with the second end of the seventh capacitor, and a collector of the fifth triode is connected with the second end of the seventeenth resistor; a first end of the eighteenth resistor is connected with an emitting electrode of the fifth triode, and a second end of the eighteenth resistor is connected with a negative electrode of the third power supply; a fifteenth resistor, a first end of the fifteenth resistor being connected to the second end of the seventh capacitor; a sixteenth resistor, wherein a first end of the sixteenth resistor is connected to a second end of the fifteenth resistor; a first end of the eighth capacitor is connected with a first end of the sixteenth resistor, and a second end of the eighth capacitor is connected with a negative electrode of the third power supply; a ninth capacitor, a first end of the ninth capacitor being connected to a second end of the sixteenth resistor; a nineteenth resistor, a first end of the nineteenth resistor being connected to a first end of the twenty-first resistor; a sixth triode, wherein the sixth triode is of an NPN type, a base of the sixth triode is connected to the second end of the ninth capacitor, and a collector of the sixth triode is connected to the second end of the nineteenth resistor; a twenty-first resistor, a first end of which is connected to the emitter of the sixth triode, and a second end of which is connected to the cathode of the third power supply; a twenty-second resistor, a first end of the twenty-second resistor connected to a first end of the twenty-first resistor; a twenty-third resistor, a first end of the twenty-third resistor being connected to a second end of the twenty-second resistor, a second end of the twenty-third resistor being connected to a negative terminal of the third power supply; a twenty-fourth resistor, a first end of the twenty-fourth resistor being connected to the second end of the ninth capacitor; a first end of the potentiometer is connected with a second end of the twenty-fourth resistor, and a second end of the potentiometer is connected with a third end of the potentiometer; and a first end of the tenth capacitor is connected with the second end of the nineteenth resistor, and a second end of the tenth capacitor is connected with the third end of the potentiometer and the input end of the phase-sensitive detection unit.

Optionally, the modulation unit includes: the modulation disc is positioned between the fire source and the flat mirror, the modulation disc is rotatably arranged relative to the flat mirror, and a light through hole is formed in the modulation disc; the magnetic steel is arranged on the modulation disk; and the driving end of the driving unit is magnetically connected with the magnetic steel, and the driving unit drives the magnetic steel to rotate so as to enable the light through hole to rotate relative to the flat mirror.

Optionally, the driving unit includes: the first inductor is magnetically connected with the magnetic steel; a thirteenth capacitor, a first end of the thirteenth capacitor being connected to the first end of the first inductor; the second inductor is magnetically connected with the magnetic steel, and the second end of the second inductor is connected with the second end of the first inductor; a first end of the twelfth capacitor is connected with the first end of the second inductor, and a second end of the twelfth capacitor is connected with the second end of the thirteenth capacitor; a twenty-fifth resistor, wherein a first end of the twenty-fifth resistor is connected with a first end of the twelfth capacitor, and a second end of the twenty-fifth resistor is connected with a second end of the twelfth capacitor; a fourth power supply, wherein the positive electrode of the fourth power supply is connected with the second end of the second inductor; a seventh triode, wherein the seventh triode is of an NPN type, a base of the seventh triode is connected with the second end of the thirteenth capacitor, a collector of the seventh triode is connected with the first end of the thirteenth capacitor, and an emitter of the seventh triode is connected with a negative electrode of the fourth power supply; a twenty-sixth resistor, wherein a first end of the twenty-sixth resistor is connected with a collector of the seventh triode; a twenty-seventh resistor, a first end of the twenty-seventh resistor being connected to a second end of the twenty-sixth resistor; a fourteenth capacitor, a first end of which is connected to a first end of the twenty-sixth resistor, and a second end of which is connected to a second end of the twenty-sixth resistor; the base electrode of the eighth triode is connected with the second end of the twenty-seventh resistor; a twenty-eighth resistor, wherein a second end of the twenty-eighth resistor is connected to a collector of the eighth triode; a twenty-ninth resistor, wherein a first end of the twenty-ninth resistor is connected with an emitter of the eighth triode; a positive electrode of the fifth power supply is connected with a first end of the twenty-eighth resistor, a negative electrode of the fifth power supply is connected with a second end of the twenty-ninth resistor, and a negative electrode of the fifth power supply is grounded; the anode of the first diode is connected with the second end of the twenty-ninth resistor, and the cathode of the first diode is connected with the base of the eighth triode; a thirty-third resistor, wherein a first end of the thirty-third resistor is connected with a first end of the twenty-eighth resistor; a thirty-second resistor, wherein a first end of the thirty-second resistor is connected with a first end of the thirty-second resistor; a second diode, an anode of the second diode being connected to the second end of the thirty-second resistor; a thirty-third resistor, a first end of the thirty-third resistor being connected to the cathode of the second diode, and a second end of the thirty-third resistor being connected to the second end of the twenty-ninth resistor; a ninth triode, wherein the ninth triode is of an NPN type, a base of the ninth triode is connected to the second end of the thirty-second resistor, a collector of the ninth triode is connected to the second end of the thirty-second resistor, and an emitter of the ninth triode is connected to the second end of the twenty-ninth resistor; a first end of the fifteenth capacitor is connected with the second end of the twenty-eighth resistor, and a second end of the fifteenth capacitor is connected with the cathode of the second diode; a thirty-first resistor, wherein a first end of the thirty-first resistor is connected to a second end of the thirty-first resistor; a thirty-fifth resistor, a first end of the thirty-fifth resistor being connected to the second end of the thirty-first resistor, and a second end of the thirty-fifth resistor being connected to the second end of the thirty-third resistor; a thirty-fourth resistor, a first end of the thirty-fourth resistor being connected to a first end of the thirty-second resistor; a sixteenth capacitor, wherein a first end of the sixteenth capacitor is connected to the second end of the thirty-second resistor, and a second end of the sixteenth capacitor is connected to the second end of the thirty-fourth resistor; and the base electrode of the thirteenth diode is connected with the second end of the thirty-first resistor, the collector electrode of the thirteenth diode is connected with the second end of the thirty-fourth resistor, and the emitter electrode of the thirteenth diode is connected with the second end of the thirty-fifth resistor.

Optionally, the phase-sensitive detection unit further includes: a seventeenth capacitor, wherein a first end of the seventeenth capacitor is connected to a second end of the thirtieth resistor; a thirty-eighth resistor, wherein a second end of the thirty-eighth resistor is connected with a second end of the seventeenth capacitor; a nineteenth capacitor, a first end of the nineteenth capacitor being connected to a second end of the tenth capacitor; a thirty-sixth resistor, wherein a second end of the thirty-sixth resistor is connected with a second end of the nineteenth capacitor; the base electrode of the eleventh triode is connected with the first end of the thirty-eighth resistor, the collector electrode of the eleventh triode is connected with the negative electrode of the fifth power supply, and the emitter electrode of the eleventh triode is connected with the first end of the thirty-sixth resistor; a thirty-ninth resistor, wherein a second end of the thirty-ninth resistor is connected to a second end of the seventeenth capacitor; a thirty-seventh resistor, wherein a first end of the thirty-seventh resistor is connected with a second end of the thirty-sixth resistor; a twelfth triode, wherein the twelfth triode is of an NPN type, a base of the twelfth triode is connected with the first end of the thirty-ninth resistor, a collector of the twelfth triode is connected with a negative electrode of the fifth power supply, and an emitter of the twelfth triode is connected with the second end of the thirty-seventh resistor; and a first end of the eighteenth capacitor is connected with the first end of the thirty-sixth resistor and the first end of the display unit, and a second end of the eighteenth capacitor is connected with the second end of the thirty-seventh resistor and the second end of the display unit.

Optionally, the early warning detection system further includes: and the anode of the alarm unit is connected with the anode of the fifth power supply, the cathode of the alarm unit is connected with the cathode of the fifth power supply, and the signal input end of the alarm unit is connected with the second end of the tenth capacitor.

The technical scheme provided by the disclosure can comprise the following beneficial effects:

the mode of carrying out the conflagration early warning through the infrared ray that detects the fire source radiation makes the operation personnel can in time judge out the emergence of conflagration to make the conflagration eliminated among the bud, avoided great life and loss of property, effectively improved the security of production.

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

Drawings

The foregoing and/or additional aspects and advantages of the present disclosure will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

fig. 1 is a schematic circuit diagram of an infrared fire source early warning detection system according to an embodiment of the present disclosure;

fig. 2 is a schematic circuit diagram of an infrared fire source early warning detection system according to an embodiment of the disclosure;

fig. 3 is a schematic structural diagram of an optical unit in the infrared fire source early warning detection system according to an embodiment of the disclosure;

fig. 4 is a schematic structural diagram of a modulation unit in an infrared fire source early warning detection system according to an embodiment of the disclosure;

fig. 5 is a schematic structural diagram of a chopper wheel in an infrared fire source early warning detection system according to an embodiment of the present disclosure;

as shown in the figure: 1. the device comprises an infrared sensing unit, a modulation unit, a phase-sensitive detection unit, a display unit, a convex lens, a flat mirror, a modulation disc, a magnetic steel, a light through hole and a phase-sensitive detection unit, wherein the infrared sensing unit 2, the modulation unit 3, the phase-sensitive detection unit 4, the display unit 5, the convex lens 6, the flat mirror 7, the modulation disc 8, the magnetic steel 9 and the light through hole are arranged on the modulation disc;

ra, a thermistor, rb, a compensation resistor, rc, a potentiometer, R1, a first resistor, R2, a second resistor, R3, a third resistor, R4, a fourth resistor, R5, a fifth resistor, R6, a sixth resistor, R7, a seventh resistor, R8, an eighth resistor, R9 and a ninth resistor; r10, tenth resistor, R11, eleventh resistor, R12, twelfth resistor, R13, thirteenth resistor, R14, fourteenth resistor, R15, fifteenth resistor, R16, sixteenth resistor, R17, seventeenth resistor, R18, eighteenth resistor, R19, nineteenth resistor, R20, twentieth resistor, R21, twenty-first resistor, R22, twenty-second resistor, R23, twenty-third resistor, R24, twenty-fourth resistor, R25, twenty-fifth resistor, R26, twenty-sixth resistor, R27, twenty-seventh resistor, R28, twenty-eighth resistor, R29, twenty-ninth resistor, R30, thirty-fourth resistor, R31, thirty-eleventh resistor, R32, thirty-second resistor, R33, thirty-third resistor, R34, thirty-fourth resistor, R35, thirty-fifth resistor, R36, thirty-sixth resistor, R37, thirty-seventh resistor, R38, thirty-fifth resistor, R39, thirty-ninth resistor;

c1, a first capacitor, C2, a second capacitor, C3, a third capacitor, C4, a fourth capacitor, C5, a fifth capacitor, C6, a sixth capacitor, C7, a seventh capacitor, C8, an eighth capacitor, C9, a ninth capacitor, C10, a tenth capacitor, C11, an eleventh capacitor, C12, a twelfth capacitor, C13, a thirteenth capacitor, C14, a fourteenth capacitor, C15, a fifteenth capacitor, C16, a sixteenth capacitor, C17, a seventeenth capacitor, C18, an eighteenth capacitor, C19 and a nineteenth capacitor;

the transistor comprises a Q1, a first triode, a Q2, a second triode, a Q3, a third triode, a Q4, a fourth triode, a Q5, a fifth triode, a Q6, a sixth triode, a Q7, a seventh triode, a Q8, an eighth triode, a Q9, a ninth triode, a Q10, a thirteenth triode, a Q11, an eleventh triode, a Q12 and a twelfth triode;

u1, a first power supply, U2, a second power supply, U3, a third power supply, U4, a fourth power supply, U5 and a fifth power supply;

d1, a first diode, D2 and a second diode;

A. an attenuator;

TI and microamp.

Detailed Description

Reference will now be made in detail to the embodiments of the present disclosure, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are illustrative only for the purpose of explaining the present disclosure, and are not to be construed as limiting the present disclosure. Rather, the embodiments of the disclosure include all changes, modifications and equivalents coming within the spirit and terms of the claims appended thereto.

As shown in fig. 1, an infrared fire source early warning and detecting system provided in the embodiment of the present disclosure includes an infrared sensing unit 1, a modulating unit 2, a phase-sensitive detecting unit 3 and a display unit 4, wherein a detecting end of the infrared sensing unit 1 detects infrared rays radiated by a fire source, a modulating end of the modulating unit 2 is disposed between the detecting end of the infrared sensing unit 1 and the fire source, an input end of the phase-sensitive detecting unit 3 is electrically connected to an output end of the infrared sensing unit 1 and an output end of the modulating unit 2, an output end of the phase-sensitive detecting unit is electrically connected to an input end of the display unit 4, and the phase-sensitive detecting unit 3 outputs a signal to the display unit 4 according to a comparison result between an output signal of the infrared sensing unit 1 and an output signal of the modulating unit 2, so that the display unit 4 displays a temperature of the fire source.

It can be understood that the infrared ray radiated by the fire source is modulated by the modulation unit 2, detected by the infrared sensing unit 1 and converted into a temperature electric signal, and sent to the phase-sensitive detection unit 3, meanwhile, the modulation unit 2 provides a reference temperature threshold value for the phase-sensitive detection unit 3, and the phase-sensitive detection unit 3 compares the temperature electric signal output by the infrared sensing unit 1 with the temperature threshold electric signal output by the modulation unit 2, so that the display unit 4 displays the temperature of the fire source.

This kind of mode through detecting the infrared ray of burning things which may cause a fire disaster radiation carries out the conflagration early warning, makes the operation personnel can in time judge out the emergence of conflagration to make the conflagration be eliminated among the bud, avoided great life and loss of property, effectively improved the security of production.

It should be noted that the fire source refers to an object that is easily combustible, such as: coal blocks, wood blocks, etc.

The reference temperature threshold provided by the modulation unit 2 for the phase-sensitive detection unit 3 can be set according to actual needs, and is not limited herein.

When the early warning detection system is applied to the field of coal, the coal oxidation condition is different, and the infrared rays radiated by the coal are also different, so that the oxidation condition of the coal can be obtained by detecting the infrared rays radiated by the coal, and then early warning is carried out before the coal is combusted, so that operating personnel can timely eliminate the fire in the bud.

As shown in fig. 2, in some embodiments, the infrared sensing unit 1 includes a thermistor Ra that detects infrared rays radiated from a fire source, a compensation resistor Rb that is connected to a first end of the thermistor Ra, a positive electrode of the first power source U1 is connected to a second end of the thermistor Ra, a negative electrode of the first power source U1 is grounded, a positive electrode of the second power source U2 is connected to a negative electrode of the first power source U1, and a negative electrode of the second power source U2 is connected to a second end of the compensation resistor Rb.

It can be understood that the thermistor Ra is used for receiving infrared rays radiated by a fire source, the compensation resistor Rb is used for temperature compensation, the first power supply U1 and the second power supply U2 are used for providing bias voltage, when infrared rays radiated by the fire source are not received, the thermistor Ra, the compensation resistor Rb, the first power supply U1 and the second power supply U2 form a stable bridge structure, and when infrared rays radiated by the fire source are received, the resistance value of the thermistor Ra decreases along with the increase of temperature, so that the bridge is unbalanced, and then an electric signal is output, so as to realize temperature detection.

It should be noted that the thermistor Ra may be a semiconductor sheet made of oxides of manganese, cobalt, and nickel, and the semiconductor sheet has a temperature coefficient of-4%, can detect milliwatt-level radiation energy, and does not need refrigeration when working at room temperature, thereby effectively ensuring high sensitivity of the early warning detection system.

The compensation resistor Rb can be shielded through a shielding net, a shielding case and the like, so that the compensation resistor Rb is only used for temperature compensation, and the stable detection of the infrared sensing unit 1 on infrared rays is ensured.

The range of variation in the resistance value of the thermistor Ra can be set according to actual needs, and is not limited herein.

The resistance value of the compensation resistor Rb may be set according to actual needs, and is not limited herein.

The output voltage values of the first power supply U1 and the second power supply U2 can be set according to actual needs, for example: the output voltage values of the first power supply U1 and the second power supply U2 are 15V.

As shown in fig. 3, in some embodiments, the early warning detection system further comprises an optical unit comprising a convex lens 5 and a flat mirror 6, the convex lens 5 is disposed between the fire source and the thermistor Ra, the focal point of the convex lens 5 is located on the thermistor Ra, the flat mirror 6 is disposed between the convex lens 5 and the fire source, and the flat mirror 6 is made of zinc sulfide material.

It can be understood that the infrared rays radiated by the fire source sequentially pass through the flat mirror 6 and the convex lens 5 and then reach the thermistor Ra, wherein the arrangement of the convex lens 5 enables the infrared rays radiated by the fire source to be focused on the thermistor Ra, so that the receiving area of the thermistor Ra is greatly reduced, the noise of the thermistor Ra is reduced, and the detection capability of the infrared sensing unit 1 is improved; by arranging the flat mirror 6 made of a zinc sulfide material, the convex lens 5, the thermistor Ra and other components are effectively protected, and the stability of the infrared sensing unit 1 is higher.

It should be noted that a cylindrical structure may be provided, the flat mirror 6 is disposed at one end of the cylindrical structure, and the convex lens 5 and the infrared sensing unit 1 are disposed in the cylindrical structure, so as to ensure stable detection of the infrared sensing unit 1. The sizes of the convex lens 5 and the flat lens 6 can be set according to actual needs, wherein the infrared rays transmitted by the flat lens 6 and the convex lens 5 ensure that the radiation energy change value received by the thermistor Ra is larger than the noise equivalent power of the thermistor.

The convex lens 5 may be a germanium lens which does not transmit visible light and ultraviolet rays but transmits infrared rays, and enables the thermistor Ra to obtain a spectral response of 2 to 18 μm, thereby ensuring stable detection of the infrared sensor unit 1, and the flat mirror 6 made of zinc sulfide material can prevent water vapor, dust, etc. from damaging the germanium lens, thereby preventing the coating film of the germanium lens from falling off. Wherein, the transmissivity of zinc sulfide in the spectral range of 1-13 μm is 70%, which can ensure the stable detection of the infrared sensing unit 1.

The optical unit may have a field of view of 1.5 degrees by 1.5 degrees, with a measurable target volume of 50 square centimeters at 5 meters from the source, with the most accurate measurement being taken when the source fills the field of view of the optical unit.

In some embodiments, the early warning detection system further includes a first amplifying unit, an input end of the first amplifying unit is electrically connected to an output end of the infrared sensing unit 1, an input end of the second amplifying unit is electrically connected to an output end of the first amplifying unit, and an output end of the second amplifying unit is connected to an input end of the phase-sensitive detection unit 3.

It can be understood that the output signal of the infrared sensing unit 1 is amplified through the arrangement of the first amplifying unit and the second amplifying unit, and the sensitivity of the early warning detection system is effectively improved.

As shown in fig. 2, in some embodiments, the first amplifying unit includes a third power source U3, a tenth resistor R10, a fifth capacitor C5, a first capacitor C1, a first resistor R1, a second resistor R2, a third resistor R3, a first transistor Q1, a fourth resistor R4, a second capacitor C2, a third capacitor C3, a sixth resistor R6, a fifth resistor R5, a seventh resistor R7, a second transistor Q2, an eighth resistor R8, a fourth capacitor C4, a third transistor Q3, and a ninth resistor R9, a negative electrode of the third power source U3 is grounded, a second end of the tenth resistor R10 is connected to an anode of the third power source U3, a first end of the fifth capacitor C5 is connected to a first end of the tenth resistor R10, a second end of the fifth capacitor C5 is grounded, a first end of the first capacitor C1 is connected to an output terminal of the infrared sensing unit 1, a first end of the first resistor R1 is connected to a cathode of the first resistor R10, a second end of the second resistor R2 is connected to a collector of the second resistor R3, a second resistor R2 is connected to an emitter of the second resistor R3, a second end of the third resistor R3 is connected to a second resistor R3, a second resistor R2, a second terminal of the second resistor R3 is connected to a third resistor R3, a second resistor R3 is connected to an emitter of the second resistor R3, a second end of the sixth resistor R6 is connected to a negative electrode of the third power source U3, a first end of the fifth resistor R5 is connected to a first end of the tenth resistor R10, a second end of the fifth resistor R5 is connected to a second end of the third capacitor C3, a first end of the seventh resistor R7 is connected to a first end of the tenth resistor R10, the second triode Q2 is of NPN type, a base of the second triode Q2 is connected to a second end of the fifth resistor R5, a collector of the second triode Q2 is connected to a second end of the seventh resistor R7, a first end of the eighth resistor R8 is connected to an emitter of the second triode Q2, a second end of the eighth resistor R8 is connected to a negative electrode of the third power source U3, a first end of the fourth capacitor C4 is connected to an emitter of the second triode Q2, a second end of the fourth capacitor C4 is connected to a negative electrode of the third power source U3, the third triode Q3 is of NPN type, a base of the third triode Q3 is connected to a third end of the seventh resistor R7, a collector of the third resistor Q3 is connected to a negative electrode of the ninth resistor R9, and a collector of the third resistor R3 is connected to a tenth resistor R9.

It can be understood that the third power supply U3 provides a working voltage for the first amplification unit, and the output voltage of the third power supply U3 can meet the use requirement of the first amplification unit through the voltage division effect of the tenth resistor R10, and meanwhile, the harmful cross-connection influence of the second amplification unit on the first amplification unit is effectively reduced through the arrangement of the fifth capacitor C5, and the stable amplification of the output signal of the infrared sensing unit 1 by the first amplification unit is ensured;

through the arrangement of the first resistor R1, the second resistor R2, the third resistor R3 and other components, bias voltage is provided for the first triode Q1, so that the first triode Q1 amplifies voltage signals output by the infrared sensing unit 1, and meanwhile, through the voltage feedback of the second capacitor C2, the input impedance of the first amplifying unit is further improved, so that the high output impedance of the infrared sensing unit 1 is adapted;

through the setting of parts such as fifth resistance R5, seventh resistance R7, eighth resistance R8, for second triode Q2 and third triode Q3 provide bias voltage, and through the direct coupling of second triode Q2 and third triode Q3, through the output as whole with the projecting pole of third triode Q3, thereby reduced holistic output impedance when continuing to amplify 1 output signal of infrared sensing unit, guarantee the adaptation to second amplifier unit, and make whole have stronger interference killing feature, guarantee that first amplifier unit is to the stable of 1 output signal of infrared sensing unit and amplify.

It should be noted that the output voltage value of the third power supply U3 can be set according to actual needs, for example: 15V, and the operating voltage value of the first amplifying unit after voltage division by the tenth resistor R10 may also be set according to actual needs, for example: 8.5V.

The NPN-type first triode Q1, the second triode Q2 and the third triode Q3 respectively comprise two N (Negative) type semiconductors and a P (Positive) type semiconductor, the P type semiconductor is arranged between the two N type semiconductors, the first triode Q1, the second triode Q2 and the third triode Q3 respectively comprise a Base electrode (Base), an Emitter electrode (Emitter) and a Collector electrode (Collector), the Emitter electrode and the Collector electrode are disconnected in the cut-off state, and the Emitter electrode and the Collector electrode are connected in the conduction state.

The resistances of the first resistor R1, the second resistor R2, the third resistor R3, the fourth resistor R4, the fifth resistor R5, the sixth resistor R6, the seventh resistor R7, the eighth resistor R8, the ninth resistor R9, and the tenth resistor R10 may be set according to actual needs, and are not limited herein.

The capacitance values of the first capacitor C1, the second capacitor C2, the third capacitor C3, the fourth capacitor C4 and the fifth capacitor C5 may be set according to actual needs, and are not limited herein.

As shown in fig. 2, in some embodiments, the second amplifying unit includes an eleventh resistor R11, an attenuator a, a twelfth resistor R12, a twenty-first resistor R21, an eleventh capacitor C11, a thirteenth resistor R13, a fourth transistor Q4, a fourteenth resistor R14, a sixth capacitor C6, a seventh capacitor C7, a seventeenth resistor R17, a fifth transistor Q5, an eighteenth resistor R18, a fifteenth resistor R15, a sixteenth resistor R16, an eighth capacitor C8, a ninth capacitor C9, a nineteenth resistor R19, a sixth transistor Q6, a twentieth resistor R20, a twenty-second resistor R22, a twenty-third resistor R23, a twenty-fourth resistor R24, a potentiometer Rc, and a tenth capacitor C10, a first end of the eleventh resistor R11 is connected to a first end of the tenth resistor R10, a first end of the attenuator a is connected to an emitter of the third transistor Q3, a third end of the attenuator a is connected to a third end of the eleventh resistor R11, a first end of a twelfth resistor R12 is connected to the fourth end of the attenuator a, a second end of the twelfth resistor R12 is connected to the negative electrode of the third power source U3, a first end of a twenty-first resistor R21 is connected to the second end of a tenth resistor R10, a second end of the twenty-first resistor R21 is connected to the positive electrode of the third power source U3, a first end of an eleventh capacitor C11 is connected to the first end of the twenty-first resistor R21, a second end of the eleventh capacitor C11 is grounded, a first end of a thirteenth resistor R13 is connected to the first end of the twenty-first resistor R21, the fourth transistor Q4 is NPN-type, a base of the fourth transistor Q4 is connected to the second end of the attenuator a, a collector of the fourth transistor Q4 is connected to the second end of the thirteenth resistor R13, a first end of the fourteenth resistor R14 is connected to the emitter of the fourth transistor Q4, a second end of the fourteenth resistor R14 is connected to the negative electrode of the third power source U3, a first end of a sixth capacitor C6 is connected to an emitter of the fourth triode Q4, a second end of the sixth capacitor C6 is connected to a negative electrode of the third power source U3, a first end of a seventh capacitor C7 is connected to a second end of a thirteenth resistor R13, a first end of a seventeenth resistor R17 is connected to a first end of a twenty-first resistor R21, the fifth triode Q5 is NPN-type, a base of the fifth triode Q5 is connected to a second end of the seventh capacitor C7, a collector of the fifth triode Q5 is connected to a second end of the seventeenth resistor R17, a first end of an eighteenth resistor R18 is connected to an emitter of the fifth triode Q5, a second end of the eighteenth resistor R18 is connected to a negative electrode of the third power source U3, a first end of a fifteenth resistor R15 is connected to a second end of the seventh capacitor C7, a first end of a sixteenth resistor R16 is connected to a second end of the fifteenth resistor R15, a first end of the eighth capacitor C8 is connected to a first end of a sixteenth resistor R16, a second end of the eighth resistor C8 is connected to a negative electrode of the third power source U3, a first end of the ninth capacitor C9 is connected to a second end of the sixteenth resistor R16, a first end of the nineteenth resistor R19 is connected to a first end of the twenty-first resistor R21, the sixth transistor Q6 is NPN-type, a base of the sixth transistor Q6 is connected to a second end of the ninth capacitor C9, a collector of the sixth transistor Q6 is connected to a second end of the nineteenth resistor R19, a first end of the twentieth resistor R20 is connected to an emitter of the sixth transistor Q6, a second end of the twentieth resistor R20 is connected to a negative electrode of the third power source U3, a first end of the twenty-second resistor R22 is connected to a first end of the twenty-first resistor R21, a first end of the twenty-third resistor R23 is connected to a second end of the twenty-second resistor R22, a second end of the twenty-third resistor R23 is connected to a negative electrode of the third power source U3, a first end of the twenty-fourth resistor R24 is connected to a second end of the ninth capacitor C9, the first end of the potentiometer Rc is connected to the second end of the twenty-fourth resistor R24, the second end of the potentiometer Rc is connected to the third end of the potentiometer Rc, the first end of the tenth capacitor C10 is connected to the second end of the nineteenth resistor R19, and the second end of the tenth capacitor C10 is connected to the third end of the potentiometer Rc and the input end of the phase-sensitive detection unit 3.

It can be understood that the third power supply U3 provides a working voltage for the second amplifying unit, and the output voltage of the third power supply U3 can meet the use requirement of the second amplifying unit through the voltage division effect of the twenty-first resistor R21, and meanwhile, through the setting of the eleventh capacitor C11, the harmful cross connection between the first amplifying unit and the second amplifying unit is effectively reduced, and the stable amplification of the output signal of the infrared sensing unit 1 by the second amplifying unit is ensured;

the attenuator A receives the output signal of the first amplifying unit and outputs a signal to a fourth triode Q4 of the second amplifying unit, so that impedance matching between the first amplifying unit and the second amplifying unit is improved, and stable amplification of the output signal of the infrared sensing unit 1 by the second amplifying unit is ensured;

through the arrangement of the eleventh resistor R11, the twelfth resistor R12, the seventeenth resistor R17 and other components, bias voltage is provided for the fourth triode Q4 and the fifth triode Q5, so that the fourth triode Q4 and the fifth triode Q5 amplify the voltage signal output by the infrared sensing unit 1 for the second time, the high sensitivity of the early warning detection system is ensured, meanwhile, the seventeenth resistor R17 is connected with the collector electrode of the fourth triode Q4, and through the arrangement of the sixteenth resistor R16 and the eighth capacitor C8, the alternating voltage output by the seventeenth resistor R17 is short-circuited through the eighth capacitor C8, the gain of the second amplification unit is further improved, and the stability of a direct current working point is ensured;

through the arrangement of the twenty-fourth resistor R24, the potentiometer Rc, the tenth capacitor C10 and other components, and the characteristic of the output of the collector and the emitter of the sixth triode Q6 in an inverted phase, when the resistance value of the potentiometer Rc is adjusted, the output signal of the second amplifying unit can be shifted within 180 degrees, so that the second amplifying unit can be adaptive to the phase-sensitive detection unit 3;

it should be noted that the operating voltage value of the second amplifying unit after voltage division by the twenty-first resistor R21 may be set according to actual needs, for example: 9V.

The NPN-type fourth triode Q4, the NPN-type fifth triode Q5 and the NPN-type sixth triode Q6 respectively comprise two N-type semiconductors and a P-type semiconductor, the P-type semiconductor is arranged between the two N-type semiconductors, the fourth triode Q4, the fifth triode Q5 and the sixth triode Q6 respectively comprise a base electrode, an emitting electrode and a collecting electrode, the emitting electrode and the collecting electrode are disconnected in a cut-off state, and the emitting electrode and the collecting electrode are connected in a conducting state.

Resistance values of the eleventh resistor R11, the twelfth resistor R12, the thirteenth resistor R13, the fourteenth resistor R14, the fifteenth resistor R15, the sixteenth resistor R16, the seventeenth resistor R17, the eighteenth resistor R18, the nineteenth resistor R19, the twentieth resistor R20, the twenty-first resistor R21, the twenty-second resistor R22, the twenty-third resistor R23, and the twenty-fourth resistor R24 may be set according to actual needs, and are not limited herein.

The capacitance values of the sixth capacitor C6, the seventh capacitor C7, the eighth capacitor C8, the ninth capacitor C9, the tenth capacitor C10 and the eleventh capacitor C11 may be set according to actual needs, and are not limited herein.

The type of the attenuator A can be set according to actual needs, and is not limited herein.

The potentiometer Rc includes a first terminal, a second terminal and a third terminal, the potentiometer Rc is generally composed of a resistor and a movable brush, the first terminal and the second terminal of the potentiometer Rc are disposed at two ends of the resistor, the third terminal of the potentiometer Rc is disposed on the brush, and the brush moves along the resistor to make the potentiometer Rc obtain a resistance value having a certain relation with a displacement amount of the brush. The specific resistance value of the potentiometer Rc can be set according to actual needs, and is not limited herein.

The capacitance values of the fifth capacitor C5 and the eleventh capacitor C11 can be reduced, and the resistance values of the tenth resistor R10 and the twenty-first resistor R21 can be increased to prevent the self-oscillation while satisfying the amplification effects of the first amplification unit and the second amplification unit.

As shown in fig. 3, 4 and 5, in some embodiments, the modulation unit 2 includes a modulation disk 7, a magnetic steel 8 and a driving unit, the modulation disk 7 is located between the fire source and the flat mirror 6, the modulation disk 7 is rotatably disposed relative to the flat mirror 6, a light through hole 9 is disposed on the modulation disk 7, the magnetic steel 8 is disposed on the modulation disk 7, a driving end of the driving unit is magnetically connected to the magnetic steel 8, and the driving unit drives the magnetic steel 8 to rotate, so that the light through hole 9 rotates relative to the flat mirror 6.

It can be understood that the driving unit generates a changing magnetic field to rotate the magnetic steel 8, the magnetic steel 8 rotates to drive the modulation disc 7 to rotate, and the modulation disc 7 rotates to drive the light through hole 9 to rotate relative to the flat mirror 6, so that infrared rays radiated by a fire source are converted into alternating radiation to be input into the phase-sensitive detection unit 3 after being amplified by the first amplifying unit and the second amplifying unit, and high-sensitivity detection is realized.

It should be noted that a cover structure may be provided, the reticle 7 is fixed at one end of the cover structure, the other end of the cover structure is rotatably sleeved on the barrel structure, and the magnetic steel 8 is fixed on the cover structure.

The installation position and the magnetic pole orientation of the magnetic steel 8 can be set according to actual needs, and are not limited here.

The size of the light through hole 9 can be set according to actual needs, for example: the clear aperture 9 enables the width of the blade formed on the reticle 7 to be equal to one quarter of the circumference of the reticle 7.

As shown in fig. 2, in some embodiments, the driving unit includes a first inductor, a thirteenth capacitor C13, a second inductor, a twelfth capacitor C12, a twenty-fifth resistor R25, a fourth power source U4, a seventh transistor Q7, a twenty-sixth resistor R26, a twenty-seventh resistor R27, a fourteenth capacitor C14, an eighth transistor Q8, a twenty-eighth resistor R28, a twenty-ninth resistor R29, a fifth power source U5, a first diode D1, a thirty-fourth resistor R30, a thirty-second resistor R32, a second diode D2, a thirty-third resistor R33, a ninth transistor Q9, a fifteenth capacitor C15, a thirty-eleventh resistor R31, a thirty-fifth resistor R35, a thirty-fourth resistor R34, a sixteenth capacitor C16, a thirteenth resistor Q10, a first inductor is magnetically connected to the magnetic steel 8, a first terminal of a thirteenth capacitor C13 is connected to a first terminal of the first inductor, a second inductor is magnetically connected to the magnetic steel 8, a second terminal of the second inductor is connected to a collector of the thirteenth resistor Q7, a twelfth resistor R7 is connected to a collector of the twelfth resistor R7, a second resistor R7 is connected to a base of the thirteenth resistor R7, a fifth resistor Q7 is connected to a base of the fifth inductor Q7, a fifth resistor R7, a second resistor R7 is connected to a fifth resistor R7 to a fifth resistor R12, a collector of the fifth resistor R7 is connected to a fifth resistor R7 to a triode C7, a first end of the fourteenth capacitor C14 is connected to a first end of the twenty-sixth resistor R26, a second end of the fourteenth capacitor C14 is connected to a second end of the twenty-sixth resistor R26, the eighth transistor Q8 is NPN type, a base of the eighth transistor Q8 is connected to a second end of the twenty-seventh resistor R27, a second end of the twenty-eighth resistor R28 is connected to a collector of the eighth transistor Q8, a first end of the twenty-ninth resistor R29 is connected to an emitter of the eighth transistor Q8, an anode of the fifth power source U5 is connected to a first end of the twenty-eighth resistor R28, a cathode of the fifth power source U5 is connected to a second end of the twenty-ninth resistor R29, a cathode of the first diode D1 is connected to a base of the eighth transistor Q8, a first end of the thirty resistor R30 is connected to a first end of the twenty-eighth resistor R28, a first end of the thirty-second resistor R32 is connected to a first end of the thirty-second resistor R30, an anode of the second diode D2 is connected to a second end of the thirty-second resistor R32, a first end of the thirty-third resistor R33 is connected to a cathode of the second diode D2, a second end of the thirty-third resistor R33 is connected to a second end of the twenty-ninth resistor R29, the ninth triode Q9 is NPN-type, a base of the ninth triode Q9 is connected to a second end of the thirty-second resistor R32, a collector of the ninth triode Q9 is connected to a second end of the thirty-second resistor R30, an emitter of the ninth triode Q9 is connected to a second end of the twenty-ninth resistor R29, a first end of the fifteenth capacitor C15 is connected to a second end of the twenty-eighth resistor R28, a second end of the fifteenth capacitor C15 is connected to a cathode of the second diode D2, a first end of the eleventh resistor R31 is connected to a second end of the thirty-second resistor R30, a first end of the thirty-fifth resistor R35 is connected to a second end of the thirty-first resistor R31, a second end of the thirty-fifth resistor R35 is connected to a second end of the thirty-third resistor R33, a first end of the thirty-fourth resistor R34 is connected to a first end of the thirty-second resistor R32, a first end of the sixteenth capacitor C16 is connected to a second end of the thirty-second resistor R32, a second end of the sixteenth capacitor C16 is connected to a second end of the thirty-fourth resistor R34, the thirteenth diode Q10 is of NPN type, a base of the thirteenth diode Q10 is connected to a second end of the thirty-first resistor R31, a collector of the thirteenth diode Q10 is connected to a second end of the thirty-fourth resistor R34, and an emitter of the thirteenth diode Q10 is connected to a second end of the thirty-fifth resistor R35.

It can be understood that the fourth power supply U4 provides operating voltages for the first inductor, the thirteenth capacitor C13, the twelfth capacitor C12, and the like to ensure stable driving of the modulation unit 2, and the fifth power supply U5 provides operating voltages for the eighth transistor Q8, the ninth transistor Q9, and the like to provide a reference temperature threshold for the phase-sensitive detection unit 3;

through the arrangement of the parts such as the thirteenth capacitor C13, the twelfth capacitor C12 and the like, a changing magnetic field is generated on the first inductor, so that the magnetic steel 8 is driven to rotate by the changing magnetic field, and the rotation of the modulation disk 7 is further realized;

meanwhile, the second inductor senses the rotation of the magnetic steel 8 and outputs a pulse signal to the seventh triode Q7, the seventh triode Q7 transmits the pulse signal to the eighth triode Q8 through the arrangement of the twenty-sixth resistor R26, the fourteenth capacitor C14 and the like, the eighth triode Q8 forms an inverter circuit through the arrangement of the twenty-seventh resistor R27, the twenty-eighth resistor R28 and the like, the pulse signal is shaped, the shaped signal is transmitted to the ninth triode Q9 and the thirteenth polar tube Q10 through the differentiation of the fifteenth capacitor C15 and the thirty-third resistor R33 and the like, the ninth triode Q9 and the thirteenth polar tube Q10 form a timing monostable trigger through the arrangement of the thirty resistor R30, the thirty-eleventh resistor R31, the thirty-second resistor R32 and the like, and the timing monostable trigger outputs a square wave with the same frequency as that of the second amplifying circuit to the phase sensitive detection circuit, so that the reference temperature threshold value is provided to the phase sensitive detection circuit.

It should be noted that the output voltage value of the fourth power supply U4 can be set according to actual needs, for example: 3V.

The output voltage value of the fifth power supply U5 can be set according to actual needs, for example: 3V. The working voltage values of the inverter circuit and the timing monostable flip-flop can also be set according to actual needs, for example: 9V.

The NPN-type seventh triode Q7, the eighth triode Q8, the ninth triode Q9 and the thirteenth triode Q10 respectively comprise two N-type semiconductors and one P-type semiconductor, the P-type semiconductor is arranged between the two N-type semiconductors, the seventh triode Q7, the eighth triode Q8, the ninth triode Q9 and the thirteenth triode Q10 respectively comprise a base electrode, an emitting electrode and a collecting electrode, the emitting electrode and the collecting electrode are disconnected in the cut-off state, and the emitting electrode and the collecting electrode are connected in the conduction state.

The inductance values of the first inductor and the second inductor can be set according to actual needs, and are not limited herein.

The resistance values of the twenty-fifth resistor R25, the twenty-sixth resistor R26, the twenty-seventh resistor R27, the twenty-eighth resistor R28, the twenty-ninth resistor R29, the thirty-third resistor R30, the thirty-eleventh resistor R31, the thirty-second resistor R32, the thirty-third resistor R33, the thirty-fourth resistor R34, and the thirty-fifth resistor R35 may be set according to actual needs, which is not limited herein.

The capacitance values of the twelfth capacitor C12, the thirteenth capacitor C13, the fourteenth capacitor C14, the fifteenth capacitor C15 and the sixteenth capacitor C16 may be set according to actual needs, and are not limited herein.

The types of the first diode D1 and the second diode D2 can be set according to actual needs, and are not limited herein.

As shown in fig. 2, in some embodiments, the phase-sensitive detector unit 3 further includes a seventeenth capacitor C17, a thirty-eighth resistor R38, a nineteenth capacitor C19, a thirty-sixth resistor R36, an eleventh transistor Q11, a thirty-ninth resistor R39, a thirty-seventh resistor R37, a twelfth transistor Q12, and an eighteenth capacitor C18, a first end of the seventeenth capacitor C17 is connected to the second end of the thirty-fourth resistor R30, a second end of the thirty-eighth resistor R38 is connected to the second end of the seventeenth capacitor C17, a first end of the nineteenth capacitor C19 is connected to the second end of the tenth capacitor C10, a second end of the thirty-sixth resistor R36 is connected to the second end of the nineteenth capacitor C19, the eleventh transistor Q11 is PNP type, a base of the eleventh transistor Q11 is connected to a first end of the thirty-eighth resistor R38, a collector of the eleventh transistor Q11 is connected to a negative electrode of the fifth power source U5, an emitter of the eleventh triode Q11 is connected to a first end of the thirty-sixth resistor R36, a second end of the thirty-ninth resistor R39 is connected to a second end of the seventeenth capacitor C17, a first end of the thirty-seventh resistor R37 is connected to a second end of the thirty-sixth resistor R36, the twelfth triode Q12 is NPN type, a base of the twelfth triode Q12 is connected to a first end of the thirty-ninth resistor R39, a collector of the twelfth triode Q12 is connected to a negative electrode of the fifth power source U5, an emitter of the twelfth triode Q12 is connected to a second end of the thirty-seventh resistor R37, a first end of the eighteenth capacitor C18 is connected to a first end of the thirty-sixth resistor R36 and a first end of the display unit 4, and a second end of the eighteenth capacitor C18 is connected to a second end of the thirty-seventh resistor R37 and a second end of the display unit 4.

It can be understood that the fifth power supply U5 provides operating voltages for the eleventh transistor Q11, the twelfth transistor Q12, etc. to enable the phase-sensitive detection unit 3 to compare the temperature electrical signal output by the infrared sensing unit 1 with the temperature threshold electrical signal output by the modulation unit 2, so as to enable the display unit 4 to display the temperature of the fire source;

through the arrangement of the thirty-eighth resistor R38, the thirty-ninth resistor R39, the thirty-sixth resistor R36 and other components and the signal output of the second amplifying unit and the timing monostable trigger, the eleventh triode Q11 and the twelfth triode Q12 are alternately conducted, so that the current of the display unit 4 is conducted along the fixed direction, and the temperature electric signal output by the infrared sensing unit 1 of the display unit 4 is compared with the temperature threshold electric signal output by the modulation unit 2 to display the temperature of the fire source.

It should be noted that the display unit 4 may be a microammeter TI having a pointer, when the temperature output by the infrared sensing unit 1 is less than the temperature threshold output by the modulation unit 2, the pointer of the microammeter TI is biased to be negative, and when the temperature output by the infrared sensing unit 1 is greater than or equal to the temperature threshold output by the modulation unit 2, the pointer of the microammeter TI is biased to be positive and displays the temperature output by the infrared sensing unit 1.

The microammeter TI can detect the output signal of the phase-sensitive detection unit 315mV by appropriately adjusting the output phase of the second amplification unit.

The NPN-type twelfth triode Q12 includes two N-type semiconductors and one P-type semiconductor, the P-type semiconductor being disposed between the two N-type semiconductors, and the twelfth triode Q12 includes a base, an emitter, and a collector, and is turned off when turned off, and is turned on when turned on.

The PNP type eleventh triode Q11 comprises an N-type semiconductor and two P-type semiconductors, wherein the N-type semiconductor is arranged between the two P-type semiconductors, the eleventh triode Q11 comprises a base electrode, an emitting electrode and a collecting electrode, the emitting electrode and the collecting electrode are disconnected in the cut-off state, and the emitting electrode and the collecting electrode are connected in the conducting state.

The resistance values of the thirty-sixth resistor R36, the thirty-seventh resistor R37, the thirty-eighth resistor R38 and the thirty-ninth resistor R39 can be set according to actual needs, and are not limited herein.

The capacitance values of the seventeenth capacitor C17, the eighteenth capacitor C18 and the nineteenth capacitor C19 may be set according to actual needs, and are not limited herein.

As shown in fig. 2, in some embodiments, the early warning detection system further includes an alarm unit, an anode of the alarm unit is connected to an anode of the fifth power source U5, a cathode of the alarm unit is connected to a cathode of the fifth power source U5, and a signal input end of the alarm unit is connected to the second end of the tenth capacitor C10.

It can be understood that the fifth power supply U5 supplies power to the alarm unit, so that the alarm unit can stably alarm; when the display unit 4 displays the temperature of the fire source, the second amplifying unit transmits a signal to the alarm unit so that the alarm unit gives an alarm, thereby better reminding an operator to process in time and avoiding the occurrence of a large fire.

It should be noted that the alarm unit may be an audible alarm, a light alarm, or an audible and visual alarm.

In the description of the present disclosure, the terms "first," "second," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. Further, in the description of the present disclosure, "a plurality" means two or more unless otherwise specified.

Any process or method descriptions in flow charts or otherwise described herein may be understood as representing modules, segments, or portions of code which include one or more executable instructions for implementing specific logical functions or steps in the process, and alternate implementations are included within the scope of the preferred embodiment of the present disclosure in which functions may be executed out of order from that shown or discussed, including substantially concurrently or in reverse order, depending on the functionality involved, as would be understood by those reasonably skilled in the art of the embodiments of the present disclosure.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present disclosure. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

Although embodiments of the present disclosure have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present disclosure, and that changes, modifications, substitutions and alterations may be made to the above embodiments by those of ordinary skill in the art within the scope of the present disclosure.

Claims

1. An infrared fire source early warning detection system, comprising:

the detection end of the infrared sensing unit detects infrared rays radiated by the fire source;

the modulation end of the modulation unit is arranged between the detection end of the infrared sensing unit and the fire source;

the input end of the phase-sensitive detection unit is electrically connected with the output end of the infrared sensing unit and the output end of the modulation unit;

and the output end of the phase-sensitive detection unit is electrically connected with the input end of the display unit, and the phase-sensitive detection unit outputs a signal to the display unit according to a comparison result of the output signal of the infrared sensing unit and the output signal of the modulation unit so as to enable the display unit to display the temperature of the fire source.

2. The infrared fire alarm detection system of claim 1, wherein the infrared sensing unit comprises:

a thermistor that detects infrared rays radiated from the fire source;

the first end of the compensation resistor is connected with the first end of the thermistor;

the positive electrode of the first power supply is connected with the second end of the thermistor, and the negative electrode of the first power supply is grounded;

and the anode of the second power supply is connected with the cathode of the first power supply, and the cathode of the second power supply is connected with the second end of the compensation resistor.

3. The infrared fire alarm detection system of claim 2, wherein the alarm detection system further comprises:

an optical unit, the optical unit comprising: the fire source comprises a convex lens and a flat mirror, wherein the convex lens is arranged between the fire source and the thermistor, the focus of the convex lens is positioned on the thermistor, the flat mirror is arranged between the convex lens and the fire source, and the flat mirror is made of a zinc sulfide material.

4. The infrared fire alarm detection system of claim 1, 2 or 3, wherein the alarm detection system further comprises:

the input end of the first amplifying unit is electrically connected with the output end of the infrared sensing unit;

and the input end of the second amplifying unit is electrically connected with the output end of the first amplifying unit, and the output end of the second amplifying unit is connected with the input end of the phase-sensitive detection unit.

5. The infrared fire alarm detection system of claim 4, wherein the first amplification unit comprises:

a third power supply, a negative electrode of the third power supply being grounded;

a tenth resistor, a second end of the tenth resistor being connected to the positive electrode of the third power supply;

a first end of the fifth capacitor is connected with a first end of the tenth resistor, and a second end of the fifth capacitor is grounded;

the first end of the first capacitor is connected with the output end of the infrared sensing unit;

a first end of the first resistor is connected with a first end of the tenth resistor;

a first end of the second resistor is connected with a second end of the first resistor, and a second end of the second resistor is connected with a negative electrode of the third power supply;

a first end of the third resistor is connected with the second end of the first capacitor, and a second end of the third resistor is connected with the first end of the second resistor;

the base electrode of the first triode is connected with the first end of the third resistor, and the collector electrode of the first triode is connected with the first end of the tenth resistor;

a first end of the fourth resistor is connected with an emitting electrode of the first triode, and a second end of the fourth resistor is connected with a negative electrode of the third power supply;

a first end of the second capacitor is connected with a first end of the second resistor, and a second end of the second capacitor is connected with an emitter of the first triode;

a first end of the third capacitor is connected with a second end of the second capacitor;

a first end of the sixth resistor is connected with a second end of the third capacitor, and a second end of the sixth resistor is connected with a negative electrode of the third power supply;

a first end of the fifth resistor is connected with a first end of the tenth resistor, and a second end of the fifth resistor is connected with a second end of the third capacitor;

a first end of the seventh resistor is connected with a first end of the tenth resistor;

the base electrode of the second triode is connected with the second end of the fifth resistor, and the collector electrode of the second triode is connected with the second end of the seventh resistor;

a first end of the eighth resistor is connected with an emitting electrode of the second triode, and a second end of the eighth resistor is connected with a negative electrode of the third power supply;

a first end of the fourth capacitor is connected with an emitting electrode of the second triode, and a second end of the fourth capacitor is connected with a negative electrode of the third power supply;

a third triode, wherein the base of the third triode is connected with the second end of the seventh resistor, and the collector of the third triode is connected with the first end of the tenth resistor;

and a first end of the ninth resistor is connected with the emitter of the third triode, and a second end of the ninth resistor is connected with the negative electrode of the third power supply.

6. The infrared fire alarm detection system of claim 5, wherein the second amplification unit comprises:

a first end of the eleventh resistor is connected with a first end of the tenth resistor;

the first end of the attenuator is connected with the emitter of the third triode, and the third end of the attenuator is connected with the second end of the eleventh resistor;

a first end of the twelfth resistor is connected with the fourth end of the attenuator, and a second end of the twelfth resistor is connected with the negative electrode of the third power supply;

a twenty-first resistor, wherein a first end of the twenty-first resistor is connected to a second end of the tenth resistor, and a second end of the twenty-first resistor is connected to a positive electrode of the third power supply;

a first end of the eleventh capacitor is connected with a first end of the twenty-first resistor, and a second end of the eleventh capacitor is grounded;

a thirteenth resistor, a first end of the thirteenth resistor being connected to a first end of the twenty-first resistor;

a fourth triode, wherein the base of the fourth triode is connected with the second end of the attenuator, and the collector of the fourth triode is connected with the second end of the thirteenth resistor;

a fourteenth resistor, a first end of which is connected to the emitter of the fourth transistor, and a second end of which is connected to the cathode of the third power supply;

a first end of the sixth capacitor is connected with an emitter of the fourth triode, and a second end of the sixth capacitor is connected with a negative electrode of the third power supply;

a first end of the seventh capacitor is connected with the second end of the thirteenth resistor;

a seventeenth resistor, a first end of the seventeenth resistor being connected to a first end of the twenty-first resistor;

a fifth triode, wherein the fifth triode is of an NPN type, a base of the fifth triode is connected with the second end of the seventh capacitor, and a collector of the fifth triode is connected with the second end of the seventeenth resistor;

a first end of the eighteenth resistor is connected with an emitting electrode of the fifth triode, and a second end of the eighteenth resistor is connected with a negative electrode of the third power supply;

a fifteenth resistor, a first end of the fifteenth resistor being connected to the second end of the seventh capacitor;

a sixteenth resistor, wherein a first end of the sixteenth resistor is connected to a second end of the fifteenth resistor;

a first end of the eighth capacitor is connected with a first end of the sixteenth resistor, and a second end of the eighth capacitor is connected with a negative electrode of the third power supply;

a ninth capacitor, a first end of the ninth capacitor being connected to a second end of the sixteenth resistor;

a nineteenth resistor, a first end of the nineteenth resistor being connected to a first end of the twenty-first resistor;

a sixth triode, wherein the sixth triode is of an NPN type, a base of the sixth triode is connected to the second end of the ninth capacitor, and a collector of the sixth triode is connected to the second end of the nineteenth resistor;

a twenty-first resistor, a first end of which is connected to the emitter of the sixth triode, and a second end of which is connected to the cathode of the third power supply;

a twenty-second resistor, a first end of the twenty-second resistor connected to a first end of the twenty-first resistor;

a twenty-third resistor, a first end of the twenty-third resistor being connected to a second end of the twenty-second resistor, a second end of the twenty-third resistor being connected to a negative terminal of the third power supply;

a twenty-fourth resistor, a first end of the twenty-fourth resistor being connected to the second end of the ninth capacitor;

a first end of the potentiometer is connected with a second end of the twenty-fourth resistor, and a second end of the potentiometer is connected with a third end of the potentiometer;

and a first end of the tenth capacitor is connected with the second end of the nineteenth resistor, and a second end of the tenth capacitor is connected with the third end of the potentiometer and the input end of the phase-sensitive detection unit.

7. The infrared fire alarm detection system of claim 6, wherein the modulation unit comprises:

the modulation disc is positioned between the fire source and the flat mirror, the modulation disc is rotatably arranged relative to the flat mirror, and a light through hole is formed in the modulation disc;

the magnetic steel is arranged on the chopper wheel;

the driving end of the driving unit is magnetically connected with the magnetic steel, and the driving unit drives the magnetic steel to rotate so that the light through hole rotates relative to the flat mirror.

8. The infrared fire alarm detection system of claim 7, wherein the drive unit comprises:

the first inductor is magnetically connected with the magnetic steel;

a thirteenth capacitor, a first end of the thirteenth capacitor being connected to the first end of the first inductor;

the second inductor is magnetically connected with the magnetic steel, and the second end of the second inductor is connected with the second end of the first inductor;

a first end of the twelfth capacitor is connected with the first end of the second inductor, and a second end of the twelfth capacitor is connected with the second end of the thirteenth capacitor;

a twenty-fifth resistor, wherein a first end of the twenty-fifth resistor is connected with a first end of the twelfth capacitor, and a second end of the twenty-fifth resistor is connected with a second end of the twelfth capacitor;

a fourth power supply, wherein the positive electrode of the fourth power supply is connected with the second end of the second inductor;

a seventh triode, wherein the seventh triode is of an NPN type, a base of the seventh triode is connected with the second end of the thirteenth capacitor, a collector of the seventh triode is connected with the first end of the thirteenth capacitor, and an emitter of the seventh triode is connected with a negative electrode of the fourth power supply;

a twenty-sixth resistor, wherein a first end of the twenty-sixth resistor is connected with a collector of the seventh triode;

a twenty-seventh resistor, a first end of the twenty-seventh resistor being connected to a second end of the twenty-sixth resistor;

a fourteenth capacitor, a first end of which is connected to a first end of the twenty-sixth resistor, and a second end of which is connected to a second end of the twenty-sixth resistor;

the base electrode of the eighth triode is connected with the second end of the twenty-seventh resistor;

a twenty-eighth resistor, wherein a second end of the twenty-eighth resistor is connected to a collector of the eighth triode;

a twenty-ninth resistor, wherein a first end of the twenty-ninth resistor is connected with an emitter of the eighth triode;

a positive electrode of the fifth power supply is connected with a first end of the twenty-eighth resistor, a negative electrode of the fifth power supply is connected with a second end of the twenty-ninth resistor, and a negative electrode of the fifth power supply is grounded;

the anode of the first diode is connected with the second end of the twenty-ninth resistor, and the cathode of the first diode is connected with the base electrode of the eighth triode;

a thirty-third resistor, wherein a first end of the thirty-third resistor is connected with a first end of the twenty-eighth resistor;

a thirty-second resistor, wherein a first end of the thirty-second resistor is connected with a first end of the thirty-second resistor;

a second diode, an anode of the second diode being connected to the second end of the thirty-second resistor;

a thirty-third resistor, a first end of the thirty-third resistor being connected to the cathode of the second diode, and a second end of the thirty-third resistor being connected to the second end of the twenty-ninth resistor;

a ninth triode, wherein the ninth triode is of an NPN type, a base of the ninth triode is connected to the second end of the thirty-second resistor, a collector of the ninth triode is connected to the second end of the thirty-second resistor, and an emitter of the ninth triode is connected to the second end of the twenty-ninth resistor;

a first end of the fifteenth capacitor is connected with the second end of the twenty-eighth resistor, and a second end of the fifteenth capacitor is connected with the cathode of the second diode;

a thirty-first resistor, wherein a first end of the thirty-first resistor is connected with a second end of the thirty-first resistor;

a thirty-fifth resistor, a first end of the thirty-fifth resistor being connected to the second end of the thirty-first resistor, and a second end of the thirty-fifth resistor being connected to the second end of the thirty-third resistor;

a thirty-fourth resistor, a first end of the thirty-fourth resistor being connected to a first end of the thirty-second resistor;

a sixteenth capacitor, wherein a first end of the sixteenth capacitor is connected to the second end of the thirty-second resistor, and a second end of the sixteenth capacitor is connected to the second end of the thirty-fourth resistor;

and the base electrode of the thirteenth diode is connected with the second end of the thirty-first resistor, the collector electrode of the thirteenth diode is connected with the second end of the thirty-fourth resistor, and the emitter electrode of the thirteenth diode is connected with the second end of the thirty-fifth resistor.

9. The infrared fire source warning and detecting system of claim 8, wherein the phase sensitive detection unit further comprises:

a seventeenth capacitor, wherein a first end of the seventeenth capacitor is connected to a second end of the thirtieth resistor;

a thirty-eighth resistor, wherein a second end of the thirty-eighth resistor is connected with a second end of the seventeenth capacitor;

a nineteenth capacitor, wherein a first end of the nineteenth capacitor is connected to a second end of the tenth capacitor;

a thirty-sixth resistor, wherein a second end of the thirty-sixth resistor is connected with a second end of the nineteenth capacitor;

the base electrode of the eleventh triode is connected with the first end of the thirty-eighth resistor, the collector electrode of the eleventh triode is connected with the negative electrode of the fifth power supply, and the emitter electrode of the eleventh triode is connected with the first end of the thirty-sixth resistor;

a thirty-ninth resistor, wherein a second end of the thirty-ninth resistor is connected to a second end of the seventeenth capacitor;

a thirty-seventh resistor, wherein a first end of the thirty-seventh resistor is connected with a second end of the thirty-sixth resistor;

a twelfth triode, wherein the twelfth triode is of an NPN type, a base of the twelfth triode is connected with the first end of the thirty-ninth resistor, a collector of the twelfth triode is connected with a negative electrode of the fifth power supply, and an emitter of the twelfth triode is connected with the second end of the thirty-seventh resistor;

and a first end of the eighteenth capacitor is connected with the first end of the thirty-sixth resistor and the first end of the display unit, and a second end of the eighteenth capacitor is connected with the second end of the thirty-seventh resistor and the second end of the display unit.

10. The infrared fire alarm detection system of claim 9, wherein the alarm detection system further comprises:

and the anode of the alarm unit is connected with the anode of the fifth power supply, the cathode of the alarm unit is connected with the cathode of the fifth power supply, and the signal input end of the alarm unit is connected with the second end of the tenth capacitor.