Polynary combined type line-type heat detector
Technical field
The invention belongs to safety engineering subject moderate heat calamity detection alarm technical field; Relate to the abominable places of environment such as all kinds of long tunnels of industrial circle, travelling belt, large-scale workshop, warehouse, track traffic such as a kind of early detection that is mainly used in fire and electric power, metallurgy, petrochemical industry and since the fire overheated, that the naked light burning causes of various electric power facilities, equipment or article take place before or the initial stage monitoring abnormal state polynary combined type line-type heat detector of reporting to the police.
Background technology
The line-type heat detector that is applied in the maturation of industrial circles such as electric power, metallurgy, petrochemical industry at present mainly contains 3 kinds: on-off value linear constant temperature fire detector, analog linetype temperature-fixing fire detecting device and analog linear different constant temperature fire detector.These 3 kinds of detectors all adopt temperature sensing material to be processed into cable; The outer structure that coats sheath is surveyed mechanism and is generally the impedance variations principle, and promptly detector adopts the cable material with distinct temperature coefficient to process; When the environment temperature of detector protection changes; The impedance of cable changes, and testing circuit is according to the impedance variations of cable, and whether the scene of judging has fire to take place.Though the line-type heat detector that has is realized two-parameter or measuring multiple parameters through the quantity that increases inner temperature-sensitive cable, its structure and detection mechanism do not have the change of essence.
Line-type heat detector is in present practical applications; Mainly there is following problem: the one, receive the restriction of structure and detection mechanism, the radius of protection of a detector is limited, so limited the protection domain of detector; Increase the engineering equipment cost, reduced the practical applications cost performance.The 2nd, because application places is the strong electromagnetic place mostly, line-type heat detector is subject to electromagnetic interference (EMI), in order to prevent false alarm; Detector sensitivity is turned down; Though analog linear different constant temperature fire detector has been installed in the part place, simply shielded the differential temperature function sometimes, only keep the constant temperature warning function; Cause detector can't realize early fire detection, incured loss through delay best warning and fire fighting and rescue opportunity.The 3rd, in order to guarantee the Effect on Detecting of line-type heat detector, realize that the early detection of fire is reported to the police, the mounting means that project installation adopts contact to lay, this mode is introduced electromagnetic interference (EMI) easily, also is unfavorable for engineering maintenance and maintenance.The 4th, the line-type heat detector that uses does not at present possess monitored area temperature and warning position Presentation Function, has therefore limited the use length and the application places of detector.
Because the existence of the problems referred to above, big limitations the range of application of line-type heat detector, influenced the early stage responding ability of fire of detector.
Summary of the invention
To the deficiency that present line-type heat detector exists, the present invention provides a kind of low cost and has stronger anti-electromagnetic interference capability and the polynary combined type line-type heat detector and the implementation method of incipient fire responding ability.
For realizing the object of the invention, the present invention adopts following technical proposals:
Polynary combined type line-type heat detector, it comprises sensing unit and microprocessor; Said sensing unit adopts three core flat structures, and three heart yearn head ends are connected with microprocessor connection terminal corresponding end in the sensing unit; Microcontroller circuit is made up of front end circuit, filtering circuit, amplifying circuit, communication driving circuit, signaling control circuit, a time sign indicating number receiving circuit, host CPU processor, warning output control circuit, warning section display circuit; Second heart yearn output signal outputs to the filtering circuit input end through front end circuit, and filtering circuit output signal is connected to the host CPU input end through amplifying circuit; First heart yearn output signal exports back the sign indicating number receiving circuit to through the communication driving circuit; Return the sign indicating number receiving circuit and output signal to host CPU, the steering order of host CPU is through the input of signaling control circuit to communication driving circuit, and the output of communication driving circuit connects first heart yearn; Through first heart yearn steering order of host CPU is sent to sensing module; Realize the transmitted in both directions of data, the 3rd heart yearn is connected directly to earth potential as the data common port of first heart yearn and first heart yearn.
Said sensing unit; Adopt three core flat structures; Three heart yearns are conductor, laterally arrange, and wherein filling between second heart yearn, the 3rd heart yearn can both responsive negative temperature coefficient insulating material to slow variation or fast-changing temperature; The increase in temperature resistance descends, and forms the sensing cable with sense of continuity temperature function; Between first heart yearn, the 3rd heart yearn sensing module is set at a certain distance; Sensing module is pressed on the negative temperature coefficient insulating material; And with connection terminal and first heart yearn, the welding of the 3rd heart yearn; Infrared temperature sensor is installed on the sensing module, can be realized remote non-contact type temperature measurement.Three heart yearns add water-proof jacket.
Said sensing unit also can adopt the four-core flat structure, and quad is conductor; Laterally arrange; Wherein first heart yearn, second heart yearn, the 3rd heart yearn in first heart yearn, second heart yearn, the 3rd heart yearn and the three core flat structures is identical, and quad is parallel to the 3rd heart yearn setting, and role is consistent with the effect of the 3rd heart yearn; Only, constitute order circuit as data communication line.
Because sensing unit promptly comprises the sensing cable with sense of continuity temperature function; The sensing module that comprises highly sensitive remote temperature sensing function again; Be that line formula temperature-sensitive and point type temperature-sensitive combine; So heart yearn can be exported analog quantity and two kinds of temperature informations of digital quantity simultaneously, second heart yearn, the 3rd heart yearn are output as the analog quantity temperature information, and first heart yearn, the 3rd heart yearn are output as the digital quantity temperature information.
Sensing module by level-conversion circuit, signal decoding circuit, reply control circuit, infrared temperature sensor, semiconductor temperature sensor, channel selection circuit, signal amplification circuit, form from the CPU processor.The output signal of first heart yearn, the 3rd heart yearn exports signal decoding circuit to through level changing circuit; Signal decoding circuit outputs signal to the input end from CPU; Export level-conversion circuit from the answer information of CPU to through replying control circuit; Level translation output signal to first heart yearn, the 3rd heart yearn, realize bidirectional data transfers with microprocessor.The output of infrared temperature sensor is connected to the input of channel selection circuit, and the output of channel selection circuit is connected to the input of signal amplification circuit, and the output of signal amplification circuit is connected to the input of host CPU.The channel selecting control output of host CPU is connected to channel selection circuit, realizes the signals collecting to two kinds of different temperatures sensors.
Sensing module adopts infrared temperature sensor and semiconductor temperature sensor to realize the point type non-contact temperature measuring; Two kinds of function unanimities that sensor is realized; The measuring distance of semiconductor temperature sensor is lower than the measuring distance of infrared temperature sensor; Adopt the mode of two kinds of compound thermometrics of sensor, can take into account respectively closely and measure, improve the monitoring range of sensing module greatly with remote temperature.Consider cost factor, also can only adopt wherein a kind of temperature sensor.
Warning section display circuit is made up of LED charactron or LCD liquid crystal display, but displays temperature and alarm set point (being the sensing module address) position; The warning output control circuit comprises optocoupler and relay, and CPU output control signal is connected to relay through optocoupler, and relay output end is connected to remote control equipment, realizes the isolated controlling of reporting to the police and exporting.
The communication sequential explanation of adopting between microprocessor and the sensing module: microprocessor adopts the mode signaling of width modulation.Send out 12 information when patrolling and examining sensing module altogether, signaling is 4 of pattern positions in proper order, and 8 of address bits, pattern position and address bit are all sent out low level earlier, and the back is sent out high-order.After powering on, microprocessor from 1 to 255 order is patrolled and examined sensing module, and the midfeather certain hour is the bus charging.Sensing module adopts and draws current system to answer information, and answer information is digital quantity, answers low level during answer earlier, and the back is answered high-order.The advantage of this communications protocol is that data communication line has stronger power supply capacity, when carrying out data communication, is that sensing module provides certain power supply energy through level-conversion circuit, utilizes two buses just can realize data communication and power supply.Sensing module be in dormant state when flat from CPU; When carrying out data communication, waken up, beginning receiving mode position and address bit are after the address bit that receives and this machine address are identical; The answer stage in the communication sequential is answered this machine address date; The temperature data that is about to obtain postbacks to microprocessor through bus, and communication finishes, and begins to gather the temperature data of infrared temperature sensor and semiconductor temperature sensor from CPU; Handle the back and prepare, get into dormant state then again for data communication next time.Because time-sharing work and dormancy working method from CPU effectively reduce the power consumption of sensing module, have improved the load capacity of microprocessor greatly, the quantity of sensing module can reach 255.
Polynary combined type line-type heat detector implementation method comprises following treatment step: according to the real-time temperature data of gathering of sensing unit; Compare with the fire combustion data that is stored in advance in the host CPU; Draw the state of temperature between institute's surveillance zone, realize different constant temperature warning and environment temperature adaptive equalization.
Different constant temperature is reported to the police and the realization of environment temperature adaptive equalization comprises the steps:
At first obtain the analog input signal of second heart yearn in the sensing unit, the 3rd heart yearn, write down temperature initial value C0, obtain the digital output signal of the sensing module that connects between first heart yearn, the 3rd heart yearn; No. 1 address record temperature initial value B10; No. 2 address record temperature initial value B20, No. 3 address record temperature initial value B30, by that analogy; M address record temperature initial value Bm0 (m≤255), and write down current running time T 0;
After microprocessor gets into the normal monitoring state; Gather two kinds of different data-signals in real time; Record current temperature value Cn, B1n-Bmn, Tn differ from the rate of temperature change Δ Bm/ Δ T (m is 1-255) of the sensing module of rate of temperature change Δ C/ Δ T between Δ T=Tn-T0, second heart yearn, the 3rd heart yearn, all addresses temperature difference Δ Bm=Bmn-Bm0 (m is 1-255), the working time that calculates current temperature value that the sensing module of temperature difference Δ C=Cn-C0, all addresses of second heart yearn, the 3rd heart yearn current temperature value and initial value gathers and initial value;
The fire combustion data A, D, Δ A, the Δ D that are stored in advance in the host CPU are relevant with the temperature perception medium, obtain by the fire combustion curve, and wherein A, D are two temperature constants, and Δ A, Δ D are two temperature variations.The fire combustion curve is that the horizontal ordinate of this curve is the time in the relevant data of one group of temperature and time of standard fire combustor test and the collection of in-site modeling natural fire generating process, and ordinate is a temperature.
When satisfying Δ C/ Δ T >=Δ D or satisfy Δ Bm/ Δ T >=Δ A, carry out differential temperature and report to the police, start alarm lamp and relay, simultaneously according to the address information of sensing module, the display alarm zone field.
When satisfying Δ C >=D or satisfy Δ Bm >=A, carry out constant temperature and report to the police, start alarm lamp and relay, simultaneously according to the address information of sensing module, the display alarm zone field.
When above-mentioned two alert if all do not satisfy, replace C0 with Cn, replace Bm0 (m is 1-255) with Bmn, carry out the environment temperature adaptive equalization.
The present invention is beneficial effect and advantage compared with prior art:
1, sensing unit adopts two kinds of diverse temperature detection modes of mechanism in the fire detector of the present invention; Line formula temperature-sensitive and point type temperature-sensitive combine; Be polynary line-type heat detector truly, can improve the warning accuracy of line-type heat detector greatly.
2, the present invention has kept the characteristic of the continuous temperature-sensitive of line type fire detector; Increased infrared temperature sensor simultaneously; So can realize remote non-contact measurement; Make line-type heat detector work in higher grade of sensitivity, improved the incipient fire responding ability of line-type heat detector.
3, line-type heat detector of the present invention can adopt contactless mounting means; Can effectively avoid electromagnetic interference (EMI); Enlarged the protection area of detector when having reduced rate of false alarm; Improved the engineering adaptability of detector, compared with existing fire detector, the engineering equipment cost can reduce more than 50%.
4, line-type heat detector has warning position Presentation Function, has therefore improved the use length of detector, can enlarge the product application places.
Description of drawings
Fig. 1 sensing unit structural drawing 1;
Fig. 2 sensing unit structural drawing 2;
Fig. 3 microprocessor function figure;
Fig. 4 line-type heat detector pie graph;
Fig. 5 sensing module pie graph;
Fig. 6 communication sequential chart;
Fig. 7 software algorithm process flow diagram.
Embodiment
Below in conjunction with accompanying drawing and embodiment the present invention is described in further detail:
Referring to accompanying drawing 4, polynary combined type line-type heat detector, it comprises sensing unit and microprocessor; Said sensing unit adopts three core flat structures, 3 first heart yearns, second heart yearn, the 3rd heart yearn head end and microprocessor connection terminal A1, A2 in the sensing unit, and the A3 corresponding end connects; Microcontroller circuit is made up of front end circuit, filtering circuit, amplifying circuit, communication driving circuit, signaling control circuit, a time sign indicating number receiving circuit, host CPU processor, warning output control circuit, warning section display circuit; Second heart yearn output signal outputs to the filtering circuit input end through front end circuit, and filtering circuit output signal is connected to the host CPU input end through amplifying circuit; First heart yearn output signal exports back the sign indicating number receiving circuit to through the communication driving circuit; Return the sign indicating number receiving circuit and output signal to host CPU, the steering order of host CPU is through the input of signaling control circuit to communication driving circuit, and the output of communication driving circuit connects first heart yearn; Through first heart yearn steering order of host CPU is sent to sensing module; Realize the transmitted in both directions of data, the 3rd heart yearn is connected directly to earth potential as the data common port of first heart yearn and second heart yearn.
The long distance areas continuous temperature of sensing unit perception change information, microprocessor collection, processing and analysis temperature information, and determine whether to report to the police according to the data analysis result.
Said sensing unit adopts three core flat structures, and three heart yearns are conductor, laterally arrange.Specifically referring to accompanying drawing 1.Wherein fill negative temperature coefficient insulating material 8 between second heart yearn, the 3rd heart yearn, form cable with sense of continuity temperature function; Between first heart yearn, the 3rd heart yearn sensing module 6 is set at a certain distance; Sensing module is pressed on the negative temperature coefficient insulating material; And with connection terminal and first heart yearn, the welding of the 3rd heart yearn; Solder joint is 7, and infrared temperature sensor is installed on the sensing module, can realize non-contact type temperature measurement.Three heart yearns add water-proof jacket 5.Spacing between the sensing module 6 is a 1-8 rice, and quantity is 255 at most, so the length of sensing unit can reach 2Km.
Said sensing unit also can adopt the four-core flat structure, and quad is conductor, laterally arranges.Specifically referring to accompanying drawing 2.Wherein fill negative temperature coefficient insulating material 8 between second heart yearn, the 3rd heart yearn, form cable with sense of continuity temperature function; Between first heart yearn, the quad sensing module 6 is set at a certain distance; Sensing module is pressed on the negative temperature coefficient insulating material; And with connection terminal and first heart yearn, quad welding; Solder joint is 7, and infrared temperature sensor is installed on the sensing module, can realize non-contact type temperature measurement.Quad adds water-proof jacket 5.Spacing between the sensing module 6 is a 1-8 rice, and quantity is 255 at most, so the length of sensing unit can reach 2Km.
Because sensing unit promptly comprises the cable with sense of continuity temperature function; The sensing module that comprises highly sensitive remote temperature sensing function again; Be that line formula temperature-sensitive and point type temperature-sensitive combine; So heart yearn can be exported analog quantity and two kinds of temperature informations of digital quantity simultaneously, second heart yearn, the 3rd heart yearn are output as the analog quantity temperature information, and first heart yearn, the 3rd heart yearn are output as the digital quantity temperature information.
The terminal B1 of sensing module, B3 connect with first heart yearn, the 3rd heart yearn respectively.Sensing module by level-conversion circuit, signal decoding circuit, reply control circuit, infrared temperature sensor, semiconductor temperature sensor, channel selection circuit, signal amplification circuit, form from the CPU processor.The output signal of first heart yearn, the 3rd heart yearn exports signal decoding circuit to through level changing circuit; Signal decoding circuit outputs signal to the input end from CPU; Export level-conversion circuit from the answer information of CPU to through replying control circuit; Level translation output signal to first heart yearn, the 3rd heart yearn, realize bidirectional data transfers with microprocessor.The output of infrared temperature sensor is connected to the input of channel selection circuit, and the output of channel selection circuit is connected to the input of signal amplification circuit, and the output of signal amplification circuit is connected to the input of host CPU.The channel selecting control output of host CPU is connected to channel selection circuit, realizes the signals collecting to two kinds of different temperatures sensors.
Referring to accompanying drawing 3, microcontroller circuit is made up of front end circuit, filtering circuit, amplifying circuit, communication driving circuit, signaling control circuit, a time sign indicating number receiving circuit, host CPU processor, warning output control circuit, warning section display circuit; Second heart yearn output signal outputs to the filtering circuit input end through front end circuit, and filtering circuit output signal is connected to the host CPU input end through amplifying circuit; First heart yearn output signal exports back the sign indicating number receiving circuit to through the communication driving circuit; Return the sign indicating number receiving circuit and output signal to host CPU, the steering order of host CPU is through the input of signaling control circuit to communication driving circuit, and the output of communication driving circuit connects first heart yearn; Through first heart yearn steering order of host CPU is sent to sensing module; Realize the transmitted in both directions of data, the 3rd heart yearn is connected directly to earth potential as the data common port of first heart yearn and second heart yearn.
Referring to accompanying drawing 4, second heart yearn, the 3rd heart yearn head end connect microprocessor connection terminal A2, A3 in the sensing unit, tail end connecting terminal resistance R, and the first heart yearn head end connects microprocessor terminal A1, and tail end is unsettled.Second heart yearn output signal outputs to the filtering circuit input end through front end circuit, and filtering circuit output signal is connected to the host CPU input end through amplifying circuit; First heart yearn output signal exports back the sign indicating number receiving circuit to through the communication driving circuit; Return the sign indicating number receiving circuit and output signal to host CPU, the steering order of host CPU is through the input of signaling control circuit to communication driving circuit, and the output of communication driving circuit connects first heart yearn; Through first heart yearn steering order of host CPU is sent to sensing module; Realize the transmitted in both directions of data, the 3rd heart yearn is connected directly to earth potential as the data common port of first heart yearn and second heart yearn.
Said sensing module is referring to accompanying drawing 5.Sensing module by level-conversion circuit, signal decoding circuit, reply control circuit, infrared temperature sensor, semiconductor temperature sensor, channel selection circuit, signal amplification circuit, form from the CPU processor.The output signal of first heart yearn, the 3rd heart yearn exports signal decoding circuit to through level changing circuit; Signal decoding circuit outputs signal to the input end from CPU; Export level-conversion circuit from the answer information of CPU to through replying control circuit; Level translation output signal to first heart yearn, the 3rd heart yearn, realize bidirectional data transfers with microprocessor.The output of infrared temperature sensor is connected to the input of channel selection circuit, and the output of channel selection circuit is connected to the input of signal amplification circuit, and the output of signal amplification circuit is connected to the input of host CPU.The channel selecting control output of host CPU is connected to channel selection circuit, realizes the signals collecting to two kinds of different temperatures sensors.
Sensing module adopts infrared temperature sensor and semiconductor temperature sensor to realize the point type non-contact temperature measuring; Two kinds of function unanimities that sensor is realized; The measuring distance of semiconductor temperature sensor is lower than the measuring distance of infrared temperature sensor; Adopt the mode of two kinds of compound thermometrics of sensor, can take into account respectively closely and measure, improve the monitoring range of sensing module greatly with remote temperature.Consider cost factor, also can only adopt wherein a kind of temperature sensor.
Warning section display circuit is made up of LED charactron or LCD liquid crystal display, but displays temperature and alarm set point (being the sensing module address) position; The warning output control circuit comprises optocoupler and relay, and CPU output control signal is connected to relay through optocoupler, and relay output end is connected to remote control equipment, realizes the isolated controlling of reporting to the police and exporting.
Referring to accompanying drawing 6, the communication sequential explanation of adopting between microprocessor and the sensing module: microprocessor adopts the mode signaling of width modulation.Send out 12 information when patrolling and examining sensing module altogether, signaling is 4 of pattern positions in proper order, and 8 of address bits, pattern position and address bit are all sent out low level earlier, and the back is sent out high-order.After powering on, microprocessor from 1 to 255 order is patrolled and examined sensing module, and the midfeather certain hour is the bus charging.Sensing module adopts and draws current system to answer information, and answer information is digital quantity, answers low level during answer earlier, and the back is answered high-order.The advantage of this communications protocol is that data communication line has stronger power supply capacity, when carrying out data communication, is that sensing module provides certain power supply energy through level-conversion circuit, utilizes two buses just can realize the power supply of data communication and sensing module.Sensing module be in dormant state when flat from CPU; When carrying out data communication, waken up, beginning receiving mode position and address bit are after the address bit that receives and this machine address are identical; The answer stage in the communication sequential is answered this machine address date; The temperature data that is about to obtain postbacks to microprocessor through bus, and communication finishes, and begins to gather the temperature data of infrared temperature sensor and semiconductor temperature sensor from CPU; Handle the back and prepare, get into dormant state then again for data communication next time.Because time-sharing work and dormancy working method from CPU effectively reduce the power consumption of sensing module, have improved the load capacity of microprocessor greatly, the quantity of sensing module can reach 255.
Referring to accompanying drawing 7; Polynary combined type line-type heat detector implementation method; The temperature data that this method is gathered according to sensing unit in real time; Compare with the fire combustion data that is stored in advance in the host CPU, draw the state of temperature between institute's surveillance zone, realize different constant temperature warning and environment temperature adaptive equalization.
Different constant temperature is reported to the police and the realization of environment temperature adaptive equalization comprises the steps:
At first obtain the analog input signal of second heart yearn in the sensing unit, the 3rd heart yearn, write down temperature initial value C0, obtain the digital output signal of the sensing module that connects between first heart yearn, the 3rd heart yearn; No. 1 address record temperature initial value B10; No. 2 address record temperature initial value B20, No. 3 address record temperature initial value B30, and the like; M address record temperature initial value Bm0 (m≤255), and write down current running time T 0;
After microprocessor gets into the normal monitoring state; Gather two kinds of different data-signals in real time; Record current temperature value Cn, Bln-Bmn, Tn differ from the rate of temperature change Δ Bm/ Δ T (m is 1-255) of the sensing module of rate of temperature change Δ C/ Δ T between Δ T=Tn-T0, second heart yearn, the 3rd heart yearn, all addresses temperature difference Δ Bm=Bmn-Bm0 (m is 1-255), the working time that calculates current temperature value that the sensing module of temperature difference Δ C=Cn-C0, all addresses of second heart yearn, the 3rd heart yearn current temperature value and initial value gathers and initial value;
The fire combustion data A, D, Δ A, the Δ D that are stored in advance in the host CPU are relevant with the temperature perception medium, obtain by the fire combustion curve, and wherein A, D are two temperature constants, and Δ A, Δ D are two temperature variations.The fire combustion curve is that the horizontal ordinate of this curve is the time in the relevant data of one group of temperature and time of standard fire combustor test and the collection of in-site modeling natural fire generating process, and ordinate is a temperature.
When satisfying Δ C/ Δ T >=Δ D or satisfy Δ Bm/ Δ T >=Δ A, carry out differential temperature and report to the police, start alarm lamp and relay, simultaneously according to the address information of sensing module, the display alarm zone field.
When satisfying Δ C >=D or satisfy Δ Bm >=A, carry out constant temperature and report to the police, start alarm lamp and relay, simultaneously according to the address information of sensing module, the display alarm zone field.
When above-mentioned two alert if all do not satisfy, replace C0 with Cn, replace Bm0 (m is 1-255) with Bmn, carry out the environment temperature adaptive equalization.
Concrete principle of work: the nearby region local temperature of monitoring when line-type heat detector takes place when unusual; The impedance of the negative temperature coefficient insulating material between sensing unit second heart yearn, the 3rd heart yearn changes; Microprocessor is according to the impedance variations situation, can judge the whether breaking out of fire of detector institute monitor area.The temperature data of part sensing module monitoring simultaneously also changes, and microprocessor also can monitor whether breaking out of fire of zone according to this variation, indicates unusual position (being the sensing module address) simultaneously.The remote regional local temperature of monitoring when line-type heat detector takes place when unusual; The impedance variations of the negative temperature coefficient insulating material between sensing unit second heart yearn, the 3rd heart yearn is not obvious; But the temperature data of sensing module monitoring changes obviously; Microprocessor can be monitored the whether breaking out of fire of remote zone rapidly according to this variation, indicates simultaneously and indicates unusual position (being the sensing module address) simultaneously.When detector environment temperature of living in changes; The impedance meeting of the negative temperature coefficient insulating material between sensing unit second heart yearn, the 3rd heart yearn changes; Consistent variation can take place in the temperature data of all sensing module monitorings simultaneously; So it is because variation of ambient temperature causes unusually that microprocessor can judge that temperature data takes place according to these consistent data that change, these data are not handled or carried out ambient temperature compensation.Because having realized the remote contactless temperature of polynary combined type truly surveys; Therefore improved the incipient fire responding ability of detector; Greatly reduce the rate of false alarm of detector, increased the protection area of detector, strengthened the engineering adaptability of line-type heat detector.