CN205541247U - Two -parameter cable formula line type heat fire detector - Google Patents
Two -parameter cable formula line type heat fire detector Download PDFInfo
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- CN205541247U CN205541247U CN201620104787.0U CN201620104787U CN205541247U CN 205541247 U CN205541247 U CN 205541247U CN 201620104787 U CN201620104787 U CN 201620104787U CN 205541247 U CN205541247 U CN 205541247U
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Abstract
The utility model discloses a two -parameter cable formula line type heat fire detector forms the two tunnel different signals of telecommunication through the different thickness NTC characteristic materials of two strand heart yearn external applications of temperature sensing cable and carries out real time sensor to the temperature, handle the magnitude of voltage that obtains two differences through signal processing module respectively to this two way signal of telecommunication again to utilize the state of the change judgement detector of two different magnitude of voltages, further when the detector is in the supervision state, through predetermined poor temperature fire alarm threshold value and ding wen fire alarm threshold judgement fire alarm state, and send corresponding alarm control signal to warning circuit. The utility model discloses a fire detector has solved among the prior art detector and has judged the response lag scheduling problem to the conflagration, has improved the warning accuracy of detector to fire detector's false alarm rate has been reduced.
Description
Technical field
This utility model belongs to fire detecting and alarm technical field in safety engineering discipline, relates to a kind of two-parameter cable linear
Heat fire detector.
Background technology
Cable linear temperature sensing fire detector is generally used for the industrial occasions fire such as cable testing bridge, underground pipe gallery, cable shaft
Detection.At present, of the prior art can generally comprise by restoration type cable linear temperature sensing fire detector: computer processor,
Termination box and temperature sensing cable, temperature sensing cable typically uses two conductor strand being cladded with NTC elastomeric material to form.Work as temperature-sensitive
When cable somewhere temperature raises, between the line between its two conductors, resistance can decline immediately, when resistance decrease sets to certain
During threshold value, front end signal processor sends fire alarm signal.But the alarm temperature of this detector is by ambient temperature, temperature-sensitive
The impacts such as the temperature of cable heated part, the length of heated portion, use length, therefore can not reflect temperature-sensitive electricity completely
Cable actual heated portion temperature level.In order to reduce the rate of false alarm that above-mentioned reason causes in engineer applied, use and heighten warning
Set threshold value or reduce the mode of detector sensitivity, the most significantly delaying the change in resistance response time of temperature sensing cable,
Situation about cannot report to the police even occurs.
Due to the existence of the problems referred to above, greatly limit the range of application of the temperature sensing cable of prior art, have impact on temperature-sensitive electricity
The ability of cable fire response in early days.
Utility model content
Utility model purpose: in order to solve the deficiencies in the prior art, this utility model provides a kind of two-parameter cable linear sense
Warm fire fire detector, it is possible to utilize the different qualities parameter of temperature sensing cable, and different qualities parameter is carried out data fusion,
Fire alarm is carried out with this.
Technical scheme: for solving above-mentioned technical problem, this utility model provides a kind of two-parameter cable linear temperature sensing fire
Detector, including: temperature sensing cable, sense temperature changes and is formed the signal of telecommunication that two-way is different；
Signal processing module, Real-time Collection two path signal, respectively two path signal is carried out process and varied with temperature
The first voltage U1 that rate is different and the second voltage U2, according to described first voltage U1 and the magnitude of voltage of the second voltage U2
Change determines the state of detector, and forms alarm control signal；
And warning circuit, make alarm response according to described alarm control signal.
Wherein, described temperature sensing cable uses four core lay configuration, and first, second heart yearn is cladded with NTC characteristic insulant
Thickness identical, between two heart yearn ends connect have first terminal resistance R1, for formed first signal of telecommunication；3rd,
The thickness that quad is cladded with NTC characteristic insulant is identical, and connecting between two heart yearn ends has the second terminal resistance R2,
For forming second signal of telecommunication；Two pairs of heart yearns are cladded with the thickness difference of NTC characteristic insulant.
Wherein, described signal processing module includes:
Two independent signal processing branch roads, two signal processing branch roads use identical circuit structure, including: front end circuit,
Filter circuit and amplifying circuit；First signal processing branch road connects the head end of described first, second heart yearn, to described first
Analog electrical signal obtains the first voltage U1 after carrying out preposition amplification, filtering, secondary processing and amplifying successively；At secondary signal
Reason branch road connects described 3rd, the head end of quad, and described second analog electrical signal is carried out preposition amplification, filter successively
The second voltage U2 is obtained after ripple, secondary processing and amplifying；Amplifying circuit and described second in described first signal processing branch road
In signal processing branch road, the amplification of amplifying circuit is different；
And control unit, the shape determining detector is changed according to the magnitude of voltage of described first voltage U1 and the second voltage U2
State, the state of described detector includes: the steady statue that powers on, malfunction and monitored state；When detector is in fault
During state, described control unit sends fault alarm control signal to described warning circuit；When detector is in monitored state
Time, described control unit sends fire alarming and controlling signal according to the alarm decision rule preset to described warning circuit.
Further, the steady statue that powers on described in is: the most described first voltage U1 and the electricity of the second voltage U2
Pressure value amplitude of variation is respectively less than the stable judgment threshold preset；
Described malfunction is: when heart yearn short circuit, and described first voltage U1 and/or the second voltage U2 is 0, works as core
During line open circuit, described first voltage U1 and/or the maximum saturation value that the 2nd U2 is each self-corresponding amplifying circuit；
Described monitored state is: detector powers on after stablizing, non-faulting state.
Further, described default fire alarm judgment rule includes differential fire alarm decision rule and/or constant temperature
Fire alarm rule；
Described differential fire alarm decision rule is: when described first voltage U1 and the second voltage U2 a certain default time
Between rate of change in section when being all higher than the differential fire alarm threshold value preset, described control unit sends to described warning circuit
Differential fire alarm control signal；
Described constant temperature fire alarm rule is: stablize with each powering on as described first voltage U1 and the second voltage U2
When the difference of magnitude of voltage during state is all higher than the constant temperature alarm threshold value preset, described control unit is sent out to described warning circuit
Send constant temperature fire alarm control signal.
Beneficial effect: the two-parameter cable linear temperature sensing fire detector in this utility model, by being covered with outward different-thickness
It is real with the signal of telecommunication of inequivalence analog quantity parameter that two strand heart yearns of NTC elastomeric material make temperature sensing cable form two-way
The now real-time sensing to temperature；Meanwhile, by signal processing module this two path signal is respectively processed and obtains two
Different magnitudes of voltage, and utilize the change of two different magnitudes of voltage to judge the state of detector, it is at detector further
During monitored state, judge fire condition by default differential fire alarm threshold value and constant temperature fire alarm threshold value, and send
To the corresponding alarm control signal of warning circuit, length of being heated, ambient temperature, temperature sensing cable length pair can be substantially reduced
The impact of fire alarm, can make cable linear temperature sensing fire detector be in higher grade of sensitivity simultaneously, improve spy
Survey the warning degree of accuracy of device, and greatly reduce the false alarm rate of fire detector.
Accompanying drawing explanation
Fig. 1 is the structural representation of two-parameter cable linear temperature sensing fire detector in this utility model；
Fig. 2 is the stranded schematic diagram of temperature sensing cable in Fig. 1；
Fig. 3 is the cross section view of temperature sensing cable in Fig. 2；
Fig. 4 is the electrical block diagram of signal processing module in Fig. 1.
Detailed description of the invention
Being described in further detail this utility model below in conjunction with embodiment, this utility model is not constituted by this enforcement row
Limit.
Two-parameter cable linear temperature sensing fire detector in Fig. 1 includes: temperature sensing cable, terminal resistance, signal processing mould
Block and warning circuit, temperature sensing cable utilizes its NTC characteristic perception variations in temperature and forms the signal of telecommunication that two-way is different；Eventually
The mainly convenient adjustment to this two path signal of end resistance；Signal processing module Real-time Collection two path signal, respectively to two
The road signal of telecommunication carries out processing and obtains the voltage that the rate that varies with temperature is different, changes according to the magnitude of voltage of two-way voltage and determines detection
The state of device, forms alarm control signal according to the state of described detector；Warning circuit is according to described alarm control signal
Make alarm response.
Temperature sensing cable in Fig. 2 and Fig. 3 uses four core lay configuration, and wherein first, second heart yearn is cladded with NTC characteristic
The thickness of insulant 5 is identical, and the 3rd, that quad is cladded with the thickness of NTC characteristic insulant 5 is identical, and two
The thickness that heart yearn is cladded with NTC characteristic insulant 5 is different, and the former is more than the latter.Four heart yearns are according to certain strand
Close pitch carry out stranded after, outsourcing aging resistance, corrosion resistant waterproof insulation sheath 6.
Terminal resistance includes the first resistance R1 and the second resistance R2；One end of heart yearn is referred to as head end, and the other end is referred to as end
End, the first resistance R1 is serially connected between the end of first, second heart yearn, and the second resistance R2 is serially connected in the three, the 4th
Between the end of heart yearn.
Signal processing module in Fig. 4 includes: two independent signal processing branch roads and control unit, signal processing branch road
The signal of telecommunication passed over by temperature sensing cable obtains every pair of heart yearn after carrying out preposition amplification, filtering, secondary processing and amplifying successively
Magnitude of voltage, and pass to control unit；Control unit changes the state determining detector according to the magnitude of voltage of two voltages,
And form corresponding alarm control signal.
The signal processing branch road of above-mentioned two independence is respectively as follows: the first signal processing branch road and secondary signal processes branch road, the
One signal processing branch road connects the head end of the first heart yearn by the first binding post DW1, by the second binding post DW2
Connect the head end of the second heart yearn；Secondary signal is processed branch road and is connected the head end of the 3rd heart yearn by the 3rd binding post DW3,
The head end of quad is connected by the 4th binding post DW4；Two signal processing branch roads use identical circuit structure,
First signal processing branch road includes No. 1st front end circuit, No. 1st filter circuit, No. 1st amplifying circuit, secondary signal
Process branch road and include No. 2nd front end circuit, No. 2nd filter circuit, No. 2nd amplifying circuit；Wherein electricity is amplified on the 1st tunnel
The amplification on road differs with the amplification of No. 2nd amplifying circuit.
In the present embodiment, the state of detector is divided into: the steady statue that powers on, malfunction and monitored state, and according to
Different states pre-sets corresponding judgment threshold；After detector normally powers on, temperature sensing cable and signal processing module warp
Cross certain time stable after, it is thus achieved that the first voltage U1 and the 2nd U2 magnitude of voltage.When the first voltage U1 and the second voltage
The magnitude of voltage amplitude of variation of U2 is respectively less than the stable judgment threshold preset, then explanation temperature sensing cable steady operation, then
Corresponding states is referred to as the steady statue that powers on；If there is short circuit or open circuit between heart yearn, then temperature sensing cable cannot normally detect ring
Border temperature, therefore the present embodiment pre-sets a fault data, this fault data includes voltage when heart yearn exists short-circuit
There is magnitude of voltage during open circuit in value and heart yearn, when the magnitude of voltage of the first voltage U1 or the second voltage U2 is 0, the most right
Answer heart yearn short circuit；If during the saturation value that the magnitude of voltage of the first voltage U1 or the second voltage U2 is respective amplifying circuit maximum,
Then corresponding heart yearn open circuit；Described monitored state is: detector powers on after stablizing, non-faulting state.
Above-mentioned control unit can use common CPU processor, including: A/D conversion equipment, storage device and computing
Device, storage device is for storing accessed by default condition adjudgement condition, fire alarm judgment rule and each moment
The first voltage U1 and the magnitude of voltage of the second voltage U2；Arithmetic unit utilizes pre-according to the situation of change of two magnitudes of voltage
If the state that is presently in of condition adjudgement conditional judgment detector and utilize fire alarm judgment rule to judge fire report
Alert state；Detector is in two analog quantity voltage values of different conditions or fire alarm state and turns by A/D conversion equipment
Being changed to corresponding digital quantity signal: when detector is in malfunction, described control unit sends to described warning circuit
Fault alarm control signal；When detector is in monitored state, described control unit is according to the alarm decision rule preset
Fire alarming and controlling signal is sent to described warning circuit.
There are differences owing to two pairs of heart yearns are cladded with the thickness of NTC characteristic insulant, the amplification corresponding to its rear end simultaneously
The amplification of circuit is different, cause the resistance between first, second heart yearn and the 3rd, decline journey between quad
Spend inconsistent.By the terminal resistance that respective amplifying circuit and end are in parallel, can be by first, second heart yearn input
The magnitude of voltage of CPU processor is modulated into and varies with temperature slower signal；3rd, quad input CPU processor
Magnitude of voltage be modulated into and vary with temperature signal faster.
Specifically, in the present embodiment, control unit changes the state determining detector according to the magnitude of voltage of two voltages, and
The detailed process forming corresponding alarm control signal is as follows:
After normally working on power, CPU processor is through software filtering and certain time averaged and stores,
And after certain time is stable, the first voltage U1 obtained in real time and the magnitude of voltage of the second voltage U2 are attached in meansigma methods
Near maximum fluctuation value, using this maximum fluctuation value as the judgment threshold of the steady statue that powers on, is referred to as stablizing judgment threshold,
It is stored in the storage device of CPU processor；
After a period of time that powers on, arithmetic unit judges the first voltage U1 and the magnitude of voltage amplitude of variation of the second voltage U2
Whether it is respectively less than the stable judgment threshold preset, is to show that detector is in the steady statue that powers on, follow-up work can be carried out
Make；
After detector enters the steady statue that powers on, it is U1 (0) that storage device stores the magnitude of voltage between first, second heart yearn,
3rd, the magnitude of voltage information between quad is U2 (0), records current time T (0) simultaneously, stable as powering on
Time magnitude of voltage, arithmetic unit judges now the magnitude of voltage U1 (0) of the first voltage U1, the magnitude of voltage of the second voltage U2
Whether U2 (0) is 0 or close to a certain amount of saturated value, is 0 and shows the short circuit of corresponding heart yearn, for a certain amount of saturation capacity
Value then shows corresponding heart yearn open circuit；Otherwise, for monitored state.
When detector is monitored state, storage device stores each moment the first voltage U1 and the electricity of the second voltage U2
Pressure value and the moment of correspondence, if the current voltage value of the first voltage U1 that CPU processor receives be U1 (n) and
The current voltage value of the second voltage U2 is U2 (n), and records current time T (n)；Arithmetic unit calculates in real time
Changing value △ U1=U1 (n)-U1 (n-10) of one voltage U1, changing value △ U2=U2 (n)-U2 (n-10) of the second voltage U2,
Time changing value △ T=T (n)-T (n-10), and calculate the rate of change △ U1/ △ T of the first voltage U1, the second voltage U2
Rate of change △ U2/ △ T, the current voltage of the first voltage U1 with power on steady statue time voltage difference U1 (n)-U1 (0),
The current voltage of the second voltage U2 with power on steady statue time voltage difference U2 (n)-U2 (0)；When △ U1/ △ T,
When the value of △ U2/ △ T is more than the differential fire alarm threshold value being pre-stored within CPU processor storage device, detector
After repeatedly judging, if the most satisfied, then send differential fire alarm control signal to warning circuit；When
U1 (n)-U1 (0), the value of U2 (n)-U2 (0) meet the constant temperature fire being pre-stored within CPU processor storage device and report to the police
During threshold value, after detector the most repeatedly judges, if data are the most satisfied, then send constant temperature fire to warning circuit
Alarm control signal.
The alarm signal that warning circuit sends can be arranged as required to the light emitting diode of different colours, relay signal and
Liquid crystal display etc., in the present embodiment, the state of detector can use light emitting diode to coordinate relay to realize together, such as:
Steady statue that three light emitting diodes of red, yellow, and green flash simultaneously or normal bright expression powers on, green light flicker or normal bright expression supervise
Depending on state, amber light flicker or the normal bright simultaneous faults actuating of relay represent malfunction, blinking red lamp or normal bright while fire
Relay represents fire alarm state.
Below it is only preferred implementation of the present utility model, it should be pointed out that above row of implementing do not constitute limit to this utility model
Fixed, relevant staff is in the range of without departing from this utility model technological thought, and carried out various changes and modifications,
All fall within protection domain of the present utility model.
Claims (5)
1. a two-parameter cable linear temperature sensing fire detector, it is characterised in that including:
Temperature sensing cable, sense temperature changes and is formed the signal of telecommunication that two-way is different；
Signal processing module, Real-time Collection two path signal, respectively two path signal is processed and obtain the rate that varies with temperature the first different voltage U1 and the second voltage U2, change the state determining detector according to the magnitude of voltage of described first voltage U1 and the second voltage U2, and form alarm control signal；
And warning circuit, make alarm response according to described alarm control signal.
Two-parameter cable linear temperature sensing fire detector the most according to claim 1, it is characterized in that, described temperature sensing cable uses four core lay configuration, the thickness that first, second heart yearn is cladded with NTC characteristic insulant is identical, connect between two heart yearn ends and have first terminal resistance R1, for forming first signal of telecommunication；3rd, to be cladded with the thickness of NTC characteristic insulant identical for quad, connects and has the second terminal resistance R2, for forming second signal of telecommunication between two heart yearn ends；Two pairs of heart yearns are cladded with the thickness difference of NTC characteristic insulant.
Two-parameter cable linear temperature sensing fire detector the most according to claim 2, it is characterised in that described signal processing module includes:
Two independent signal processing branch roads, two signal processing branch roads use identical circuit structure, including: front end circuit, filter circuit and amplifying circuit；First signal processing branch road connects the head end of described first, second heart yearn, obtains the first voltage U1 after described first signal of telecommunication is carried out preposition amplification, filtering, secondary processing and amplifying successively；Secondary signal processes branch road and connects described 3rd, the head end of quad, obtains the second voltage U2 after described second signal of telecommunication is carried out preposition amplification, filtering, secondary processing and amplifying successively；In described first signal processing branch road, amplifying circuit is different from the amplification of amplifying circuit in described secondary signal process branch road；
And control unit, the state determining detector is changed according to the magnitude of voltage of described first voltage U1 and the second voltage U2, the state of described detector includes: the steady statue that powers on, malfunction and monitored state；When detector is in malfunction, described control unit sends fault alarm control signal to described warning circuit；When detector is in monitored state, described control unit sends fire alarming and controlling signal according to the fire alarm judgment rule preset to described warning circuit.
Two-parameter cable linear temperature sensing fire detector the most according to claim 3, it is characterised in that
The described steady statue that powers on is: after powering on, the magnitude of voltage amplitude of variation of described first voltage U1 and the second voltage U2 is respectively less than the stable judgment threshold preset；
Described malfunction is: when heart yearn short circuit, and described first voltage U1 and/or the second voltage U2 is 0, when heart yearn open circuit, and described first voltage U1 and/or the maximum saturation value that the 2nd U2 is each self-corresponding amplifying circuit；
Described monitored state is: detector powers on after stablizing, non-faulting state.
Two-parameter cable linear temperature sensing fire detector the most according to claim 3, it is characterised in that described default fire alarm judgment rule includes differential fire alarm decision rule and/or constant temperature fire alarm rule；
Described differential fire alarm decision rule is: when as described first voltage U1 and the second voltage U2, the rate of change in a certain preset time period is all higher than the differential fire alarm threshold value preset, and described control unit sends differential fire alarm control signal to described warning circuit；
Described constant temperature fire alarm rule is: when the difference of the magnitude of voltage during steady statue that as described first voltage U1 and the second voltage U2 and each powers on is all higher than the constant temperature alarm threshold value preset, described control unit sends constant temperature fire alarm control signal to described warning circuit.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201620104787.0U CN205541247U (en) | 2016-02-02 | 2016-02-02 | Two -parameter cable formula line type heat fire detector |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201620104787.0U CN205541247U (en) | 2016-02-02 | 2016-02-02 | Two -parameter cable formula line type heat fire detector |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107505060A (en) * | 2017-08-28 | 2017-12-22 | 天津津航计算技术研究所 | A kind of implementation method of platinum resistance temperature sensor quick self-checking |
| CN107978121A (en) * | 2017-12-29 | 2018-05-01 | 江苏中实电子有限公司 | A kind of reusable line-type heat detector and its alarm method |
| CN108877130A (en) * | 2018-08-28 | 2018-11-23 | 首安工业消防有限公司 | Heat fire detector with terminal alarms instruction function |
| CN113240876A (en) * | 2021-04-22 | 2021-08-10 | 姜玥 | Low-voltage power transmission wire and cable fire prevention and monitoring method |
-
2016
- 2016-02-02 CN CN201620104787.0U patent/CN205541247U/en active Active
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107505060A (en) * | 2017-08-28 | 2017-12-22 | 天津津航计算技术研究所 | A kind of implementation method of platinum resistance temperature sensor quick self-checking |
| CN107978121A (en) * | 2017-12-29 | 2018-05-01 | 江苏中实电子有限公司 | A kind of reusable line-type heat detector and its alarm method |
| CN107978121B (en) * | 2017-12-29 | 2024-02-09 | 江苏中实电子有限公司 | Reusable linear temperature-sensing fire detector and alarm method thereof |
| CN108877130A (en) * | 2018-08-28 | 2018-11-23 | 首安工业消防有限公司 | Heat fire detector with terminal alarms instruction function |
| CN108877130B (en) * | 2018-08-28 | 2024-03-08 | 首安工业消防有限公司 | Temperature-sensing fire detector with terminal alarm indication function |
| CN113240876A (en) * | 2021-04-22 | 2021-08-10 | 姜玥 | Low-voltage power transmission wire and cable fire prevention and monitoring method |
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