JP2007041686A - Temperature sensor and fire sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a temperature sensor for measuring the temperature in a wide range concerning a space where the temperature is sensed. <P>SOLUTION: The temperature sensor 1 comprises: a thermosensitive wire 11 having a positive thermistor characteristic, which is arranged by distribution on the ceiling, etc., of a room in the space 100 where the temperature is sensed; a resistance value measuring circuit 14 for measuring the resistance value of the thermosensitive wire; a testing circuit 13 for feeding an electric current into the thermosensitive wire 11; a reference value storage circuit 16 for measuring the resistance value when the thermosensitive wire 11 becomes the reference temperature by the electric current from the testing circuit 13 with the use of a resistance value measuring circuit 14, and storing the result; and a present temperature calculation circuit 18 for comparing the resistance value of the thermosensitive wire 11 at the present temperature with the resistance value at the reference temperature so as to calculate the present temperature. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a temperature sensor that detects a wide range of temperatures in a temperature detection region, and a fire detector using the temperature sensor.

  Many conventional temperature sensors measure locally, such as points or bars. For example, in the case of a spot-type fire detector, it reacts sensitively to the fire that occurs immediately below it, but in the case of a fire in a horizontal location, the fire is triggered after the heat flow is transmitted through the ceiling surface. Is done.

  This also applies to a temperature sensor for an air conditioner, and since the measurement point is local, a value in which the average value of the room temperature is far from the measured temperature may be detected.

  In addition, there is an air tube type differential distribution type detector as a fire detector provided with a temperature sensor for spatially detecting temperature instead of temperature detection at such a point. This type of fire detector uses a copper pipe air pipe with an inner diameter of about 2 mm as the thermal element, and distributes this air pipe in the temperature sensing space to control the pressure in the air pipe due to the fire temperature rise. It is a detection method.

  Similarly, as a fire detector with a wide range of temperature detection functions, thermocouples are used as thermal elements, thermocouple parts and connection wires are alternately connected and distributed in the temperature detection space, There is a thermocouple type differential distributed sensor that detects thermocouple electromotive force due to fire temperature rise.

In addition, a distributed temperature detection device that measures the resistance value at the standard temperature state and the resistance value at the current temperature of the heat sensing wire composed of metal wires, and calculates the current temperature from these resistance values is provided. It has been proposed (see Patent Document 1).
JP-A-3-246430

  As described above, there are various conventional fire detectors, but each has the following problems.

  Since conventional spot-type fire detectors detect the temperature locally, when measuring the temperature in the space to be detected, a difference occurs in the temperature distribution and the measured value of the temperature sensor depends on the location of the temperature sensor, the air flow, etc. There is a problem that an error occurs in the temperature average in the entire temperature sensing space.

  Conventional differential fire detectors use copper pipe air pipes as thermal elements, so special technology is required to install the air pipes so that they are not crushed. It was. In addition, since the air tube type differential distribution type detector is a detection method using air pressure, there are cases of false alarms due to low atmospheric pressure such as a large typhoon. Furthermore, there is a problem that even if the air pipe is crushed by external pressure or a hole is opened, it may cause a false alarm.

  Furthermore, the test of the air tube type differential distribution type sensor requires an operation test using a special testing machine called a manometer, and there is a problem that labor and equipment costs are heavy for the test. .

  In addition, the conventional thermocouple differential distribution type sensor requires special techniques such as caulking work between the thermocouple portion and the connection line when installed. For this reason, there existed a problem that installation work was not easy. Also, the disconnection state between the heat sensitive part and the connection line could not be detected automatically, such as determining the disconnection state by connecting a test called a meter relay tester. . This meter relay tester has a test function that sends a voltage equivalent to the thermocouple electromotive voltage to the detector to activate the detector, but it is a test of the detector itself and is used to test the electromotive voltage of the thermocouple. It was actually necessary to conduct a combustion test in a combustion pan.

  In addition, because the thermocouple electromotive force is very small, there have been cases where misreporting due to external noise occurs. In addition, the air tube type differential distribution type sensor and the thermocouple type differential type distribution type sensor are the characteristics of the differential type fire sensor. In some cases, misinformation occurred.

  In addition, the resistance value of the heat sensitive wire changes depending on the temperature at the time of measurement and its total length, and the heat sensitive wire total length may or may not be unified to a certain length depending on the situation of the construction site and the construction method. For this reason, a means for effectively storing in the detector the resistance value of the entire length of the heat sensitive wire at the reference temperature when calculating the temperature of the detected space is required. Conventionally, as a means of measuring the resistance value of the total length of the heat sensitive wire at the reference temperature, there are a method in which a person manually inputs data and a means in which a separate thermistor, thermometer, reference resistance, etc. are provided. There was a problem that the cost increased due to the complicated configuration.

  The present invention has been made to solve the above-described problems, and can accurately detect a fire without being affected by installation conditions, environments, and the like, and can reduce labor and cost required for testing, installation, and the like. It aims to provide a temperature sensor and a fire detector.

  In order to achieve the above object, the temperature sensor of the present invention comprises a thermal wire distributed in a temperature sensing region, a test means for conducting a heating test by passing a current through the thermal wire, and a resistance value of the thermal wire. Resistance value measuring means for measuring, a reference value storage means for storing a resistance value at a reference temperature of the heat sensitive wire measured by the resistance value measuring means by conducting a heating test of the heat sensitive wire in advance by the test means, Computing means for calculating a current temperature from the resistance value of the heat sensitive wire at the reference temperature stored in the reference value storage means and the resistance value of the heat sensitive wire currently measured by the resistance value measuring means. Is the gist.

  Further, the fire detector of the present invention compares the temperature sensor, storage means for storing a fire determination reference temperature, the current temperature obtained by the temperature sensor and the fire determination reference temperature, A fire determining means for determining that a fire has occurred when a temperature exceeds the fire determination reference temperature, and a signal sending means for transmitting a fire signal in the event of a fire based on the result of determination by the fire determining means. And

  The fire detector of the present invention includes the temperature sensor, storage means for storing a fire determination reference temperature increase rate, temperature change calculating means for obtaining a current temperature increase rate from the current temperature obtained by the temperature sensor, Comparing the current temperature increase rate with the fire determination reference temperature increase rate, and determining the occurrence of a fire when the current temperature increase rate exceeds the fire determination reference temperature increase rate, and the fire The gist of the present invention is to provide signal transmission means for transmitting a fire signal in the event of a fire from the result of determination by the determination means.

  The fire detector of the present invention obtains the current temperature increase rate from the temperature sensor, the storage means for storing the fire determination reference temperature and the fire determination reference temperature increase rate, and the current temperature obtained by the temperature sensor. A temperature change calculating means, comparing the current temperature with the fire determination reference temperature and the current temperature exceeds the fire determination reference temperature; and the current temperature increase rate and the fire determination reference temperature increase rate When the current temperature rise rate exceeds the fire judgment reference temperature rise rate, a fire judgment means for judging that a fire has occurred, and a fire signal in the event of a fire based on the result of judgment by the fire judgment means, The gist of the present invention is to provide signal sending means for sending.

  According to the temperature sensor of the present invention, heat sensitive wires are distributed and installed in the temperature detection region, and the resistance value of the heat sensitive wires at the reference temperature is measured and stored by performing a heating test of the heat sensitive wires with a test circuit. Since the current resistance value is measured, and this is compared with the resistance value at the reference temperature and calculated, the temperature of the temperature sensing space is detected. The temperature distribution difference between the measured value and the average temperature in the entire temperature detection region is eliminated, and the average temperature of the entire temperature detection region can be accurately detected. Moreover, the disconnection and the short circuit state of the temperature sensor can be easily measured by measuring the resistance value.

  Further, according to the fire detector of the present invention, the temperature detection is performed by distributing the heat sensitive wires in the temperature detection region, and the resistance value of the heat sensitive wires at the reference temperature by performing the heating test of the heat sensitive wires by the test circuit. Is measured and memorized, and the current resistance value is measured, and this is compared with the resistance value at this reference temperature to calculate the temperature of the temperature sensing space. With this simple construction method, construction that does not require special technology can be performed, construction costs can be reduced, and a fire detector that is not easily affected by the natural environment such as a large typhoon can be provided. In addition, since a test circuit is provided, it is possible to easily check whether or not a fire sensor that is not normally used functions normally.

  Furthermore, according to the fire detector of the present invention, the use of the above-described temperature sensor makes it possible to perform various tests such as fire judgment based on the current temperature, fire judgment based on the temperature rise rate, and fire judgment based on both the current temperature and the temperature rise rate. Can provide fire detectors based on various fire criteria.

  Hereinafter, the best mode for carrying out a temperature sensor according to the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a block diagram illustrating a configuration of a temperature sensor according to the first embodiment. FIG. 2 is a plan view showing the arrangement of temperature sensors in the first embodiment when one room is a temperature detection space.

  The temperature sensor 1 according to the first embodiment is roughly divided into a heat sensitive wire 11 that detects a temperature and a detector 12 that detects a signal of the heat sensitive wire 11 and outputs a signal as the temperature sensor 1.

  The heat sensitive wire 11 is installed over a wide range in the temperature detection region. Here, as shown in FIG. 2, they are uniformly arranged over a wide range in the vicinity of the ceiling in the temperature detection space 100 partitioned by the wall, ceiling, floor, etc. of the building that is the temperature detection region. In general, the heat sensitive wires 11 are installed on the entire ceiling surface or wall surface in an average distribution of several meters.

  As the heat sensitive wire 11, a pure metal wire such as a pure nickel wire having a relatively high temperature coefficient of resistance can be used. The temperature coefficient of pure nickel (here, the rate of increase in the resistance value per 1 ° C. when each material is linear) is + 0.00692 / ° C.

  As the heat sensitive wire 11, a conductive polymer material having a positive thermistor characteristic having a temperature coefficient higher than that of a pure nickel wire can be used.

  An example of such a conductive polymer material is PTC silicone rubber manufactured by Shin-Etsu Chemical Co., Ltd. The temperature coefficient of this PTC silicone rubber is +0.0087 to + 0.0253 / ° C. in the range of −10 ° C. to 80 ° C., about 125% to about 365% for pure nickel wire, and the temperature at which the resistance value increases with temperature. The coefficient is high. Therefore, it is more suitable than the pure nickel wire for use in the temperature sensor 1 for fire detection or the like.

  FIG. 3 is a chart showing resistance value measurement data of PTC silicone rubber manufactured by Shin-Etsu Chemical Co., Ltd. at −10 ° C. to 80 ° C. and its calculated temperature coefficient.

  The silicone rubber used here has a heat resistance of about 200.degree. For example, 1 m of PTC silicone rubber with a diameter of 2 mm, the resistance value at 20 ° C. is 4480Ω, the resistance value at 30 ° C. is 5000Ω, and the average temperature coefficient from 20 ° C. to 30 ° C. is ((5000Ω-4480Ω) / 10 ° C.) /4480Ω=0.116, indicating that the resistance value increases at a rate of 0.0116 per 1 ° C. with respect to a resistance value of 4480Ω at 20 ° C., and the resistance value increases every time the temperature increases by 1 ° C. Increase by 52.0Ω per meter. The average temperature coefficient from 20 ° C. to 30 ° C. is described below 20 ° C. in FIG. 3, and the same applies to other temperatures.

  On the other hand, the resistivity of the pure nickel wire is 7.24 × 10 −8 Ω · m. For example, a pure nickel wire 200 m with a diameter of 0.2 mm, the resistance value at 20 ° C. is 491Ω, the resistance value at 30 ° C. is 525Ω, and the average temperature coefficient from 20 ° C. to 30 ° C. is ((525Ω−491Ω) / 10 ° C. ) /491Ω=0.00692, which means that the resistance value increases at a rate of 0.00692 per 1 ° C. with respect to the resistance value Ω at 20 ° C., and the resistance value every time the temperature increases by 1 ° C. Increases by 3.4Ω per meter. In general, it is well known that the temperature coefficient of a pure nickel wire is substantially constant between about -100 ° C and about 300 ° C.

  FIG. 4 is a characteristic graph of temperature and resistance values of PTC silicone rubber manufactured by Shin-Etsu Chemical Co., Ltd. and pure nickel wire.

  While the temperature coefficient of pure nickel wire increases linearly, PTC silicone rubber manufactured by Shin-Etsu Chemical Co., Ltd. has a characteristic that the temperature coefficient increases as the temperature rises. When the temperature rises and becomes high, the temperature coefficient increases, so that the detection error is reduced and the resistance value corresponding to the temperature can be measured effectively. In addition, the temperature coefficient in the case of PTC silicone rubber manufactured by Shin-Etsu Chemical Co., Ltd. has been confirmed by experiments in the range from −10 ° C. to + 80 ° C. The temperature sensor 1 is used in the range from −10 ° C. to + 80 ° C. It becomes possible. In addition, as a fire detector, the operating temperature range according to the national certification standard is from −10 ° C. to a constant operating temperature in the case of a constant temperature type, and the nominal operating temperature can be used up to 80 ° C.

  Therefore, it can be seen that PTC silicone rubber is more preferable than the pure nickel wire as the heat sensitive wire 11.

  In addition to the PTC silicone rubber manufactured by Shin-Etsu Chemical Co., Ltd., the thermosensitive wire 11 is easier to detect the temperature than a pure nickel wire if it is a conductive polymer material having positive thermistor characteristics.

  When a conductive polymer material having positive thermistor characteristics other than PTC silicone rubber manufactured by Shin-Etsu Chemical Co., Ltd. is used as the heat sensitive wire 11, for example, the conductive polymer material is processed into a φ2 mm line and covered with an insulator. Cut to a certain length for use. The heat sensitive wire 11 is preferably installed as a pair wire to prevent external noise, and forms a loop. The heat sensitive wire 11 is connected and terminated by a method such as pressure bonding.

  Next, the configuration of the detector 12 will be described.

  As shown in FIG. 1, the detector 12 includes a test circuit 13 (test means) that performs a heating test of the heat sensitive wire 11, and a resistance value measurement circuit 14 (resistance value measure means) that measures the total resistance value of the heat sensitive wire 11. A switching circuit 15 for switching the connection of the heat sensitive wire 11 to the test circuit 13 or the resistance value measuring circuit 14, and a reference value storage circuit 16 for storing the reference value of the total resistance value at the reference temperature of the heat sensitive wire 11 (reference value storage means). A sampling circuit 17 for outputting a sampling signal at regular time intervals to the resistance value measuring circuit 14; a reference value of the resistance value at the reference temperature of the heat sensitive wire 11; a measured current resistance value; and a temperature coefficient when the heat sensitive wire temperature rises. The current temperature calculation circuit 18 (calculation means) for calculating the current temperature from the above and a signal transmission circuit 19 for outputting the current temperature information as a signal.

  If the total length and cross-sectional area of the heat sensitive wire 11 are constant, the resistance value at the reference temperature does not change. However, the resistance value of the heat sensitive wire 11 varies depending on the temperature at the time of measurement and the total length of the heat sensitive wire 11 that has been enforced at the site of the enforcement. In addition, the total length of the heat sensitive wire 11 may or may not be uniform depending on the situation at the construction site and the construction method. For this reason, the detector 12 itself measures the resistance value of the entire heat sensitive wire at the reference temperature when calculating the temperature of the temperature sensing space 100 by causing the heat sensitive wire 11 to generate heat.

  That is, in the first embodiment, at the time of construction of the heat sensitive wire 11 or at the beginning of use, a constant current is supplied from the test circuit 13 to the heat sensitive wire 11 in an environmental state where the heat sensitive wire 11 is not heated and cooled. The temperature of the heat sensitive wire 11 itself is kept constant, the resistance value measurement circuit 14 measures the resistance value at that time, and the measured resistance value is stored in the reference value storage circuit 16.

  The temperature detection operation by the detector 12 will be described.

  At the time of normal monitoring, the other two ends of the heat sensitive wire 11 forming a loop are connected to the resistance value measuring circuit 14 via the switching circuit 15 and intermittently by the sampling circuit 17, for example, every few seconds. A sampling signal (current) is sent to the resistance value measuring circuit 14, and the resistance value measuring circuit 14 intermittently measures the resistance value of the heat sensitive wire 11 according to the sampling signal.

  The measured resistance value is compared and calculated by the current temperature calculation circuit 18 with the resistance value at the reference temperature stored in the reference value storage circuit 16, and the current temperature is calculated.

  This calculation is performed from the reference value of the resistance value at the reference temperature of the heat sensitive wire 11, the measured current resistance value, and the temperature coefficient when the temperature of the heat sensitive wire rises.

Specifically, for example, when the reference value of the resistance value over the entire length of 100 m of the heat sensitive wire 11 at the reference temperature of 20 ° C. is 448Ω, and the current resistance value of the measured heat sensitive wire 11 is 600 KΩ, the current temperature detection is performed. The relationship between the temperature and the resistance value in the space 100 is based on the data in FIG.
20 ℃ ・ ・ ・ 448KΩ
30 ℃ ・ ・ ・ 500KΩ
40 ℃ ・ ・ ・ 572KΩ
50 ℃ ・ ・ ・ 670KΩ
Thus, it can be seen that the current resistance value of 600 KΩ is in the range of 40 to 50 ° C. Moreover, the average temperature coefficient of 40-50 degreeC is 0.01713 (/ degreeC) from FIG. 3, This represents the increase rate of the resistance value which increases per 1 degreeC with respect to 40 degreeC resistance value 572Kohm, 572Kohm X 0.01713 = 9.798 KΩ is the increased resistance value per 1 ° C.

Therefore, the current resistance value of 600 KΩ is
40 ° C. + (Current resistance value−resistance value at 40 ° C. close to the current resistance value) / increased resistance value per 1 ° C. = 40 ° C. + (600 KΩ−572 KΩ) /9.798 KΩ
= 40 ° C + (28KΩ / 9.798KΩ)
= 40 ° C + 2.86 ° C
= 42.8 ° C
Is calculated.

  The current temperature information obtained by this calculation is output as a signal from the signal transmission circuit 19 to, for example, an air conditioner.

  On the other hand, when the heat sensitive wire 11 is disconnected or short-circuited, the measured resistance value is extremely high (in the case of a disconnection) or extremely low (in the case of a short-circuit) as compared with the resistance value at the normal time. The resistance value measurement circuit 14 can easily determine a disconnection or a short circuit by measuring the resistance value. Even when such a disconnection or short circuit is determined, the signal transmission circuit 19 outputs a thermal wire disconnection signal or a thermal line short circuit signal.

  Next, when the heating test of the heat sensitive wire 11 is performed, the switching circuit 15 is switched to the test circuit 13 side. As a result, the heat sensitive wire 11 is connected to the test circuit 13 via the switching circuit 15.

  In the test, first, a current is passed from the test circuit 13 to the thermal wire 11. Since the heat sensitive wire 11 is basically a resistor, it generates heat when a current flows. That is, the heat sensitive wire 11 is heated by Joule heat by the current from the test circuit 13.

  Since the temperature coefficient of the conductive polymer material having the positive thermistor characteristics used here has been measured in advance, the thermal line resistance value before the heating test and the thermal line resistance value after the heating test are measured and calculated, By comparing the temperature coefficient data of a conductive polymer material having known positive thermistor characteristics with the measured temperature coefficient data, the heat sensitive wire average temperature before the heating test can be easily calculated. That is, since the temperature coefficient at each temperature is different, the temperature before the heating test can be calculated as an absolute temperature based on the temperature coefficient measured by performing the heating test.

  The test circuit 13 controls the amount of heat generated by the heat sensitive wire 11 by current and time, waits for the completion of heat generation, switches the switching circuit 15 to the normal monitoring state, and the resistance value measuring circuit 14 determines the resistance of the heat sensitive wire 11. By measuring the value, the temperature change during the heating test is measured, and it is determined whether or not the heat sensitive wire 11 shows an appropriate resistance value by the heating test. Therefore, when measuring the resistance value at the reference temperature, the time for which the current is supplied may be controlled so as to be the reference temperature.

  Alternatively, instead of controlling the amount of current and the time during which the current flows, the temperature of the heat sensitive wire is directly measured, and when the temperature reaches the reference temperature, the switching circuit 15 is switched and the resistance value at that time is measured. The resistance value at the reference temperature over the entire length of the heat sensitive wire 11 can be easily measured and stored. Note that the measurement of the reference temperature may be performed anywhere on the heat sensitive wire 11 because current is passed through the heat sensitive wire itself to generate heat as described above.

  As described above, when the temperature sensor 1 according to the first embodiment measures the temperature of the temperature detection space 100, the measurement value and the temperature detection are detected by distributing the thermal lines 11 in the temperature detection space 100. The temperature distribution difference from the temperature average in the entire space 100 is eliminated, and the temperature of the entire temperature detection space 100 can be measured. Therefore, it can be used as an average temperature sensor 1 for the entire room, and the disconnection and short-circuit state of the heat sensitive wire 11 can be easily measured, and further, a heating test of the heat sensitive wire 11 itself can be performed.

  Moreover, by having the test circuit 13, the heat sensitive wire resistance value at the average temperature of the heat sensitive wire 11 before the heating test can be converted into a heat sensitive wire resistance value at the reference temperature and stored. Also, by having the test circuit 13, it is possible to save the labor of manually measuring the resistance value of the entire length of the heat sensitive wire at the reference temperature by providing a thermistor, a thermometer, a reference resistor, and the like.

  Further, by using a conductive polymer material having positive thermistor characteristics as the heat sensitive wire 11, the temperature coefficient of the heat sensitive wire resistance value is higher than that of a metal wire, so that the heat sensitive wire is always at regular time intervals. The resistance value of the full length can be measured, and the current temperature and the temperature increase rate can be calculated from the resistance value. This also makes it possible to capture the absolute temperature.

  Therefore, such a temperature sensor 1 can be used not only for an air conditioner but also for a fire detector.

  Next, an embodiment as a fire detector will be described.

  Example 2 is an example of a constant temperature distribution type fire detector.

  FIG. 5 is a block diagram illustrating a configuration of the constant temperature distributed fire detector according to the second embodiment. In addition, the same code | symbol is attached | subjected to the same member as the above-mentioned Example 1, and those description is abbreviate | omitted.

  The constant temperature distributed fire detector 2 according to the second embodiment includes a heat sensitive wire 11 stretched in the temperature sensing space 100 and a detector 20 connected to the heat sensitive wire 11.

  The detector 20 is a test circuit 13 that performs a heating test of the heat sensitive wire 11, a resistance value measurement circuit 14 that measures the resistance value of the heat sensitive wire 11, and a switch that switches the connection of the heat sensitive wire 11 to the test circuit 13 or the resistance value measurement circuit 14. A circuit 15, a reference value storage circuit 16 for storing a reference value of the total resistance value at the reference temperature of the heat sensitive wire 11 and a fire determination reference temperature, a sampling circuit 17 for outputting a sampling signal at regular time intervals to the resistance value measuring circuit 14, The current temperature calculation circuit 18 calculates the current temperature from the reference value of the resistance value of the heat sensitive wire 11 at the reference temperature, the measured current resistance value, and the temperature coefficient when the heat sensitive wire temperature rises. Data storage circuit 21 for storing the current temperature, a constant temperature fire determination circuit 2 for performing a fire determination by comparing the current temperature with a fire determination reference temperature based on a national test And it is made of (fire determination means), and fire signal transmitting circuit 23 to the fire information to output to the fire receiver (signal sending means).

  In the second embodiment, the constant temperature fire determination circuit 22 in the detector 20 compares the current temperature by the current temperature calculation circuit 18 with the fire determination reference temperature according to the national test standard, and makes a fire determination. Therefore, the constant temperature distribution type fire detector 2 includes a data recording circuit and a constant temperature type fire determination circuit 22 for making the constant temperature distribution type fire detector 2 in the detector of the temperature sensor 1 of the first embodiment. The fire determination is performed from the temperature signal obtained by the configuration as the temperature sensor 1 described above. In the actual device configuration, the reference value storage circuit 16 is a storage device such as a semiconductor memory. Therefore, the reference value storage circuit 16 of the temperature sensor 1 is preliminarily provided with a fire determination reference temperature in the manufacturing stage. The storage means stores the fire determination reference temperature by inputting and storing the temperature.

  Since the heat sensitive wire 11 has a constant overall length and a cross-sectional area, the resistance value at the reference temperature is known in the same manner as in the first embodiment. Therefore, the resistance value at the reference temperature of the heat sensitive wire is set in advance as a reference value. The data is stored in the memory circuit 16. The reference value of the resistance value can be stored in the same manner as in the first embodiment.

  Next, the operation of the constant temperature distributed fire detector 2 will be described.

  At the time of normal monitoring, the switching circuit 15 of the detector 20 to which the heat sensitive wire 11 is connected is switched to the resistance value measurement circuit 14 side, and a current flows intermittently, for example, every few seconds by the sampling circuit 17. Then, the resistance value of the heat sensitive wire 11 is measured.

  The measured resistance value is calculated by comparing and calculating the data stored in the reference value storage circuit 16 with the current temperature calculation circuit 18. The calculation of the current temperature is the same as that of the temperature sensor 1 in the first embodiment. The obtained current temperature information is stored in the data storage circuit 21.

  The current temperature stored in the data storage circuit 21 is compared with the fire determination reference temperature by the constant temperature fire determination circuit 22 to make a fire determination. Here, when it is determined that there is a fire, it is output as a fire signal from the fire signal transmission circuit 23 to the fire receiver.

  Further, when the heat sensitive wire 11 is broken or short-circuited, it is determined from the resistance value measured in the same manner as in Example 1 that the wire is broken or short-circuited, and is output from the fire signal sending circuit 23 as a heat sensitive wire break signal or a heat sensitive wire short-circuit signal. The

  In addition, the fire signal output from the fire signal transmission circuit 23, the heat sensitive wire disconnection signal, or the heat sensitive wire short circuit signal is received by a fire receiver (not shown).

  On the other hand, when the heating test of the heat sensitive wire 11 is performed, the switching circuit 15 is switched, and the heat sensitive wire 11 is connected to the test circuit 13 via the switching circuit 15.

  When performing the test, a current is passed from the test circuit 13 to the heat sensitive wire 11. Since the heat sensitive wire 11 is a resistor, it generates heat when a current flows. The test circuit 13 controls the heat generation amount of the heat sensitive wire 11 by current and time, waits for the completion of heat generation, switches the switching circuit 15 to the normal monitoring state, and measures the resistance value of the heat sensitive wire 11 by the resistance value measuring circuit 14. Thus, the temperature change at the time of the heating test is measured, and it is determined whether or not the heat sensitive wire 11 shows an appropriate resistance value by the heating test.

  Here, the temperature of the heat sensitive wire 11 at which heat generation is completed is, for example, a temperature higher than the national certification standard. As a result, in this test operation, if a fire signal is issued, a temperature equal to or higher than the national certification standard can be normally detected, and it can be determined that the temperature is normal.

  As described above, in the constant temperature distribution type fire detector 2 according to the second embodiment, when measuring the temperature of the temperature detection space 100, the thermal wire 11 is distributed and installed in the temperature detection space 100. The difference between the measured value and the temperature average of the temperature sensing space 100 and the temperature distribution is eliminated, and the average temperature of the entire room is judged as a fire, and it can be used as a fire detector in a fire alarm facility with few false alarms. Disconnection and short circuit can be measured easily. It is also possible to perform a heating test of the heat sensitive wire 11.

  Example 3 is an example of a differential distributed fire detector.

  FIG. 6 is a block diagram illustrating a configuration of the differential distributed fire detector according to the third embodiment. In addition, the same code | symbol is attached | subjected to the same member as the above-mentioned Example 1 and Example 2, and those description is abbreviate | omitted.

  The differential distributed fire detector 3 according to the third embodiment has the same basic structure as that of the temperature sensor 1 according to the first embodiment described above, and includes a heat sensitive wire 11 stretched in the temperature sensing space 100, and The detector 30 is connected to the heat sensitive wire 11.

  The internal configuration of the detector 30 is the same as that of the second embodiment. The test circuit 13 for performing the heating test of the heat sensitive wire 11, the resistance value measuring circuit 14 for measuring the total resistance value of the heat sensitive wire 11, and the connection of the heat sensitive wire 11. Switching circuit 15 for switching to test circuit 13 or resistance value measuring circuit 14, reference value storage circuit 16 for storing the reference value of the resistance value of the full length at the reference temperature of heat sensitive wire 11, and fire judgment reference temperature, and resistance value measuring circuit 14 A current temperature calculation circuit 18 for calculating the current temperature by calculating the information of the sampling circuit 17, the reference value storage circuit 16 and the resistance value measurement circuit 14 from the temperature coefficient at the time of the heat sensitive line temperature rise; A data storage circuit 21 that stores the current temperature calculated by the current temperature calculation circuit 18, and a current temperature increase rate is calculated from a plurality of time-series current temperatures stored in the data storage circuit 21. Temperature change calculation circuit 31 (temperature change calculation means), differential fire determination circuit 32 (fire determination means) that makes a fire determination by comparing the current temperature with the fire determination reference temperature according to the national test, fire information fire It is constituted by a fire signal transmission circuit 23 that outputs to the receiver.

  Here, what is different from the second embodiment is a fire determination operation. In the third embodiment, the differential fire determination circuit 32 obtains the temperature rise rate from the current temperature by the current temperature calculation circuit 18 and a predetermined time, and the fire rise reference temperature rise based on the obtained temperature rise rate and the national certification standard. Check the rate and make a fire judgment. Such a determination is called a differential type. On the other hand, the determination as in Example 2 described above is called a constant temperature type.

  Since the configuration and operation other than the determination operation are the same as those in the second embodiment, description thereof will be omitted. That is, also in this differential distribution type fire detector, the data recording circuit for making the differential distribution type fire detector in the detector of the temperature sensor 1 of the first embodiment, the temperature change calculation circuit 31, In addition, a differential fire determination circuit 32 is provided, and the fire determination is performed after calculating the current temperature increase rate from the temperature signal obtained by the configuration as the temperature sensor 1 described above.

  It should be noted that the reference value storage circuit 16 also serves as storage means for inputting and storing the fire determination reference temperature increase rate in advance in the manufacturing stage in the third embodiment, and storing the fire determination reference temperature increase rate.

  The operation of this differential distributed fire detector will be described below.

  In the detector 30, the fire determination reference temperature increase rate is input to the reference value storage circuit 16 in advance and stored in the manufacturing stage.

  In addition, since the heat sensitive wire 11 has a constant overall length and cross-sectional area, the resistance value at the reference temperature is known in the same manner as in the first embodiment, and therefore, the reference value of the resistance value at the heat sensitive wire reference temperature is used as a reference in advance. The value is stored in the value storage circuit 16.

  At the time of normal monitoring, the switching circuit 15 of the detector 30 to which the heat sensitive wire 11 is connected is switched to the resistance value measuring circuit 14 side, and a current flows intermittently, for example, every few seconds by the sampling circuit 17. Then, the resistance value of the heat sensitive wire 11 is measured.

  The measured resistance value is compared and calculated with the data stored in the reference value storage circuit 16 by the current temperature calculation circuit 18, and the obtained current temperature information is stored in the data storage circuit 21. At this time, the temperature increase rate is obtained by taking the time stored in advance by the temperature change calculation circuit 31 to the data stored in the data storage circuit 21.

  Instead of obtaining the current temperature rise rate from such time, the current temperature measured intermittently in the data storage circuit 21 is stored in time series, and the current temperature rise rate is obtained from the plurality of stored temperatures. It may be.

  Then, the differential fire determination circuit 32 performs a fire determination by comparing the obtained temperature increase rate with the fire determination reference temperature increase rate. Here, when it is determined that there is a fire, it is output as a fire signal from the fire signal transmission circuit 23 to the fire receiver.

  Further, when the heat sensitive wire 11 is broken or short-circuited, it is determined from the resistance value measured in the same manner as in Example 1 that the wire is broken or short-circuited, and is output from the fire signal sending circuit 23 as a heat sensitive wire break signal or a heat sensitive wire short-circuit signal. The

  In addition, the fire signal output from the fire signal transmission circuit 23, the heat sensitive wire disconnection signal, or the heat sensitive wire short circuit signal is received by a fire receiver (not shown).

  On the other hand, when the heating test of the heat sensitive wire 11 is performed, the switching circuit 15 is switched, and the heat sensitive wire 11 is connected to the test circuit 13 via the switching circuit 15.

  When performing the test, a current is passed from the test circuit 13 to the heat sensitive wire 11. Since the heat sensitive wire 11 is a resistor, it generates heat when a current flows. The test circuit 13 controls the heat generation amount of the heat sensitive wire 11 by current and time, waits for the completion of heat generation, switches the switching circuit 15 to the normal monitoring state, and measures the resistance value of the heat sensitive wire 11 by the resistance value measuring circuit 14. Thus, the temperature change at the time of the heating test is measured, and it is determined whether or not the heat sensitive wire 11 shows an appropriate resistance value by the heating test.

  Here, the temperature of the heat sensitive wire 11 that completes the heat generation is set to a temperature at which the rate of temperature increase is, for example, the rate of increase in the fire determination reference temperature that is higher than the national certification standard. As a result, in this test operation, if a fire signal is issued, a temperature equal to or higher than the national certification standard can be normally detected, and it can be determined that the temperature is normal.

  As described above, in the differential distribution type fire detector according to the third embodiment, when measuring the temperature of the temperature detection space 100, the measured value and the temperature detection space 100 are distributed by installing the heat sensitive wires 11. The difference between temperature average and temperature distribution is eliminated, and the average temperature of the entire room is judged as fire, and it can be used as a fire alarm system with few false alarms. Moreover, the disconnection of the heat sensitive wire 11 and a short circuit state can be easily measured, and a heating test of the heat sensitive wire 11 can be performed.

  Example 4 is an example of a differential distributed fire detector with a constant temperature detection function having both a constant temperature type and a differential type function.

  FIG. 7 is a block diagram illustrating a configuration of the differential distributed fire detector 4 with a constant temperature detection function according to the fourth embodiment. In addition, the same code | symbol is attached | subjected to the same member as the above-mentioned Examples 1-3, and those description is abbreviate | omitted.

  The differential distributed fire detector 4 with a constant temperature detection function of the fourth embodiment has both a fire determination function based on the constant temperature type of the second embodiment and the differential type of the third embodiment. Therefore, the configuration of the detector 40 other than the differential fire determination circuit 42 with constant temperature detection is the same as in the second and third embodiments.

  The differential distributed fire detector 4 with a constant temperature detection function is configured so that the current temperature calculated by the current temperature calculation circuit 18 in the differential fire determination circuit 42 (fire determination means) with constant temperature detection is the fire determination reference temperature according to the national certification standard. When the temperature is higher than the set temperature, the current temperature and the current temperature rise rate with time are compared with the fire judgment reference temperature rise rate according to the national certification standard, and fire judgment is performed. The reference value storage circuit 16 stores a fire judgment reference temperature according to the national certification standard and a fire judgment reference temperature increase rate according to the national certification standard.

  Thereby, in the differential distribution type fire detector 4 with the constant temperature detection function, when measuring the temperature of the temperature detection space 100, the measured value and the temperature detection space 100 are distributed by installing the heat sensitive wires 11 in a distributed manner. The temperature distribution difference from the overall temperature average disappears, and the fire can be determined from the average temperature difference of the entire room and the rate of temperature rise. For this reason, when opening and closing doors in cold places, etc., past differential type distributed sensors sometimes exceeded the fire detection temperature rise rate and caused false alarms. This makes it possible to make a fire determination that takes into account the set temperature condition, and to provide a distributed fire detector as a fire alarm facility with fewer false alarms than before.

  In the fifth embodiment, a connection line is provided between the heat sensitive wire 11 and the temperature detection region.

  FIG. 8 is a block diagram illustrating a configuration of the temperature sensor 1 according to the fifth embodiment. FIG. 9 is a plan view showing the arrangement of the temperature sensor 1 in the fifth embodiment in which one room is a temperature detection space 100.

  The temperature sensor 5 is basically the same as the temperature sensor 1 of the first embodiment, and includes a thermal wire 11 and detectors 12 that are widely distributed in the temperature sensing space 100. And the detector 12 are connected by a connection line 51. Therefore, the configurations of the heat sensitive wire 11 and the detector 12, the temperature detection operation, and the test operation are the same as those in the first embodiment, and the description thereof is omitted.

  Here, the connecting wire 51 is made of a material having a smaller change in resistance value with respect to the temperature than the heat sensitive wire 11. For example, since the copper wire has a temperature coefficient of 0.0043 / ° C., which is smaller than the PTC silicone rubber manufactured by Shin-Etsu Chemical Co., Ltd., which has a positive thermistor characteristic, the resistance value of the heat sensitive wire 11 is within the temperature measurement range. There is only a negligible change with respect to the change.

  Therefore, even when such a connection line 51 is used, it is possible to perform temperature measurement and testing by exactly the same operation as the temperature sensor 1 of the first embodiment.

  By using such a connection line 51, even when the detector 12 is installed in a room different from the temperature detection space 100 or in a remote place, the temperature in a space other than the temperature detection space 100 can be detected. The temperature of only the temperature sensing space 100 can be detected.

  Such a configuration using the connection line 51 can be similarly applied to the constant temperature distributed fire detector 2 and the differential distributed fire detector.

  FIG. 10 is a block diagram showing the configuration of the constant temperature distributed fire detector 6 when the connection line 51 is used.

  As shown in FIG. 10, in the constant temperature distributed fire detector 6, the heat sensitive wire 11 and the detector 20 are connected by a connecting wire 51. Even in this case, the configuration and operation of the heat sensitive wire 11 and the detector 20 in the constant temperature type distributed fire sensor 6 may be exactly the same as those of the constant temperature type distributed fire sensor 2 in the second embodiment. it can.

  FIG. 11 is a block diagram showing the configuration of the differential distributed fire detector 7 when the connection line 51 is used.

  As shown in FIG. 11, in the differential distributed fire detector 7, the thermal wire 11 and the detector 30 are connected by a connection line 51. Even in this case, the configuration and operation of the heat sensitive wire 11 and the detector 30 in the constant temperature type distributed fire sensor 7 should be exactly the same as those of the differential type distributed fire sensor 3 in the third embodiment. Can do.

  In addition, although not shown, in the differential distributed fire sensor with a constant temperature function according to the fourth embodiment, the heat sensitive wire 11 and the detector may be similarly connected by the connecting wire 51. In this case, the configuration of the heat sensitive wire 11 and the detector and the operation thereof are exactly the same as those in the fourth embodiment.

  In each of the above-described embodiments, the example in which the thermal wire 11 is arranged in the space to detect the temperature of the space has been described. However, the present invention not only detects the temperature of the space, but also detects the temperature of the object surface evenly. It can also be used as a temperature sensor 1 for this purpose.

  FIG. 12 is a perspective view showing the arrangement of the temperature sensor 1 for detecting the temperature of the object surface in the sixth embodiment.

  As shown in the figure, when detecting the temperature of the surface of the object, the heat sensitive wire 11 may be distributed and arranged on the surface of the temperature detection object 200. In this case, the temperature detection object 200 is a temperature detection region.

  The heat sensitive wire 11 is connected to the detector 12 via the connecting wire 51. Here, the heat sensitive wire 11, the connecting wire 51, and the detector 12 are the same as those in the above-described sixth embodiment, and the operations thereof are the same as those in the first embodiment.

  The heat sensitive wire 11 is applied only to the surface of the object to be heated, and the portion from there to the detector is connected by the connecting wire 51. This is because if there is a heat sensitive wire 11 in a space portion that is away from the surface of the object to be heated between the heat sensitive wire 11 and the detector, the temperature of the space portion may be detected. This is to prevent temperature detection.

  In this way, even if the temperature is on the surface of the object, the measured value and the temperature average of the entire temperature-sensing object 200 can be measured by distributing the heat-sensitive wire 11 on the surface of the object-to-be-temperature-sensed 200. it can. In addition, disconnection and short circuit of the heat sensitive wire 11 on the surface of the object can be easily measured, and further, a heating test of the heat sensitive wire 11 itself can be performed.

  In the present embodiment, an example in which the temperature on the surface of the cylindrical object is detected has been described. However, the shape of the object is not limited to the cylindrical shape, and any special shape can be used as long as the heat sensitive line 11 can be distributed on the surface. Even a simple shape can be accommodated.

  In the configuration of this embodiment, in order to detect the temperature of the object surface with the temperature sensor, in order to reduce the temperature effect of the air outside the object, a heat insulating process such as a heat insulating tape is performed between the air and the temperature sensor. It is necessary to apply.

  As mentioned above, although the Example of this invention was described, this invention is not limited to such an Example. For example, in the above description, the detector is described as each circuit being independent, but it goes without saying that the detector may be configured by a microcomputer, LSI, or the like.

  The present invention can be used in a disaster prevention system as a temperature sensor 1 for an air conditioner, a plant, etc., or as a fire alarm system differential distribution type fire detector.

3 is a block diagram illustrating a configuration of a temperature sensor in Embodiment 1. FIG. It is a top view which shows arrangement | positioning of the temperature sensor in Example 1 at the time of setting one room as a to-be-temperature-detected space. It is a graph which shows the resistance value measurement data in -10 degreeC to 80 degreeC of PTC silicone rubber, and its calculated temperature coefficient. It is a characteristic graph of temperature and resistance value of PTC silicone rubber and pure nickel wire. It is a block diagram which shows the structure of the constant temperature type | mold fire detector of Example 2. FIG. It is a block diagram which shows the structure of the differential type | mold distributed type fire detector of Example 3. FIG. It is a block diagram which shows the structure of the differential distributed fire detector 4 with a constant temperature detection function of Example 4. FIG. FIG. 10 is a block diagram illustrating a configuration of a temperature sensor in Embodiment 5. It is a top view which shows arrangement | positioning of the temperature sensor in Example 5 at the time of setting one room as a to-be-temperature-detected space. It is a block diagram which shows the structure of the constant temperature type | mold distributed type fire detector at the time of using a connection line. It is a block diagram which shows the structure of the differential type | mold distributed type fire detector at the time of using a connecting line. FIG. 10 is a perspective view showing an arrangement of temperature sensors for detecting the temperature of an object surface in Example 6.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 5 ... Temperature sensor 2, 6 ... Constant temperature distribution type fire detector 3, 7 ... Differential distribution type fire sensor 4 ... Differential distribution type fire detector 11 with a constant temperature detection function ... Thermal wire 12, 20 , 30, 40 ... detector 13 ... test circuit 14 ... resistance value measurement circuit 15 ... switching circuit 16 ... reference value storage circuit 17 ... sampling circuit 18 ... current temperature calculation circuit 19 ... signal transmission circuit 21 ... data storage circuit 22 ... constant temperature Fire determination circuit 23 ... Fire signal transmission circuit 31 ... Temperature change calculation circuit 32 ... Differential fire determination circuit 42 ... Differential fire determination circuit 51 with constant temperature detection ... Connection line 100 ... Temperature detection space 200 ... Temperature detection object

Claims (8)

Heat sensitive wires installed in the temperature detection area;
A test means for conducting a heating test by passing an electric current through the heat sensitive wire;
Resistance value measuring means for measuring the resistance value of the heat sensitive wire;
Reference value storage means for storing a resistance value at a reference temperature of the heat sensitive wire measured by the resistance value measuring means by conducting a heating test of the heat sensitive wire in advance by the test means;
Arithmetic means for calculating the current temperature from the resistance value of the heat sensitive wire at the reference temperature stored in the reference value storage means, and the resistance value of the heat sensitive wire currently measured by the resistance value measuring means;
A temperature sensor comprising:   The temperature sensor according to claim 1, wherein the heat sensitive wire is a conductive polymer material having positive thermistor characteristics.   3. The temperature sensor according to claim 1, wherein the resistance value measuring unit measures the resistance value of the heat sensitive wire intermittently at a predetermined time interval.   4. The connection according to claim 1, wherein the heat sensitive wire and the resistance value measuring means are connected by a connection wire having a smaller resistance value change with respect to temperature than the heat sensitive wire. 5. The described temperature sensor.   The temperature sensor according to claim 1, wherein the temperature detection region is a space or an object surface. A temperature sensor according to any one of claims 1 to 5;
Storage means for storing the fire judgment reference temperature;
A fire determination means for comparing the current temperature obtained by the temperature sensor with the fire determination reference temperature and determining that a fire has occurred when the current temperature exceeds the fire determination reference temperature;
A signal sending means for sending a fire signal in the event of a fire from the result of the judgment by the fire judging means;
A fire detector characterized by comprising: A temperature sensor according to any one of claims 1 to 5;
Storage means for storing a fire judgment reference temperature rise rate;
A temperature change calculating means for obtaining a current temperature increase rate from the current temperature obtained by the temperature sensor;
A fire determination means for comparing the current temperature increase rate with the fire determination reference temperature increase rate, and determining that a fire has occurred when the current temperature increase rate exceeds the fire determination reference temperature increase rate;
A signal sending means for sending a fire signal in the event of a fire from the result of the judgment by the fire judging means;
A fire detector characterized by comprising: A temperature sensor according to any one of claims 1 to 5;
Storage means for storing the fire judgment reference temperature and the fire judgment reference temperature rise rate;
A temperature change calculating means for obtaining a current temperature increase rate from the current temperature obtained by the temperature sensor;
When the current temperature exceeds the fire judgment reference temperature by comparing the current temperature with the fire judgment reference temperature, and the current temperature rise rate is compared with the fire judgment reference temperature rise rate A fire determination means for determining that a fire has occurred when an increase rate exceeds the fire determination reference temperature increase rate;
A signal sending means for sending a fire signal in the event of a fire from the result of the judgment by the fire judging means;
A fire detector characterized by comprising:

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