A multi-channel pipe-type line type heat fire detector

Abstract

The invention relates to a multi-channel tubular linear temperature sensing fire detector which is characterized in that a detection circuit is connected with a current collector via a common joint; two common terminals of the current collector respectively are connected with input terminals of a metal gas pump and a pressure sensor; the other terminal of the pressure sensor is connected with a reference chamber; the pressure sensor is connected with a CPU via a first circuit; the CPU is connected with a multi-channel signal output terminal via a third circuit, and with a linear stepped micromotor via a second circuit; and a pressure emulation generator and the current collector are disposed on a mounting plate which is fixed in a box body. The invention can be used for early detecting overtemperature of various industrial devices or articles in a harsh environment, monitoring abnormal temperature due to spark, self-combustion, etc. and combining with an automatic fire extinguishment system. Alarm temperature, temperature raising rate and sensitivity of the fire detector can be set and regulated. The invention has the advantages of reduced engineering device numbers, increased protection area, lowered device investment, and reduced artificial mounting cost.

Description

technical field [0001] The invention relates to a multi-channel pipe-type linear temperature-sensing fire detector, specifically belonging to the technical field of fire detection and alarm in safety engineering. Background technique [0002] In the prior art, what is currently being used is the first generation of air pipe type linear differential temperature fire detectors, which mainly use switch signal alarms and rely on manual self-checking; some applications also have second-generation air detectors. Tubular linear differential temperature fire detector, which adopts a single detection pipeline and an old-fashioned self-test device. [0003] The main working principle of the first-generation air pipe detector is that when the temperature changes normally, the gas pressure in the detection pipe remains balanced. When a fire breaks out, the temperature on the spot rises sharply, and the air in the detection tube is heated and expands. When the expansion speed is greater...

AI Technical Summary

Problems solved by technology

The above-mentioned first-generation switch air pipeline type differential temperature detector has two major disadvantages: first, the air leakage or blockage of the detection tube cannot be detected automatically, and it must be detected manually by using a simple manual air injection method according to the specified time Whether there is blockage or air leakage in the pipeline. If the detection tube leaks during the detection period, the alarm cannot be reported if a fire occurs at this time.

The second is that the principle of responding to fire is to rely on mechanical contact action. This kind of switch action mode has been proved to have a high false alarm rate in both theory and practice. The reason is that the detector has no data analysis ability and cannot measure the pressure expansion rate in the pipe. Judge the comparison and rule out false positives caused by ambient temperature

First of all, the detection tube is a single tube, and the detection length is only about 100 meters. Such a microcomputer processor can only protect an area of ​​100×5=500 square meters (the detector protection area (mainly refers to space protection) is rectangular Calculate the area by multiplying the length by the width (the protection width is ±2.5 meters around the detection tube). For example, the protection area of ​​a 1-meter-long detection tube is 1×5=5 meters 2 ), the cost of the whole project is very high, and the construction volume is also very large

Second, its self-checking device uses upper and lower cam twisting to push the air pump for self-checking. However, in practical applications, it is often found that it is difficult to completely twist and match the upper and lower cams during the twisting process. It will make the air pump unable to exhaust all the gas in the pump during the self-inspection, so that the end of the detection pipeline will not be able to detect the leakage fault during the self-inspection

Third, the gas used in the detection tube is not a special gas, its detection sensitivity is not high enough, and its application range is limited

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