JPH1145380A - Fire sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To automatically discriminate a sensor type and sensitivity in a sensor part by a signal processing part by measuring a resistance value characteristic at a normal temperature and discriminating/setting the type of a thermistor or sensitivity. SOLUTION: The sensor part 2 is composed of the thermistor 3 and it is connected to the signal processing part 1 by power/signal line L. The thermistor 3 converts the temperature change of the room temperature into a resistance value change. The signal processing part 1 is composed of a temperature detection circuit 10, a fire signal circuit 11 and a type discrimination part 12. The type discrimination circuit 12 applies DC current to the sensor part 2 at the time of regular monitoring. When the fire sensor is installed, the resistance value of the thermistor 3 is measured. It is discriminated whether the connected thermistor 3 is a constant temperature-type sensor or a differential type sensor as the fire sensor, or discriminates sensitivity types for respective types, a constant temperature-type sensor 60 deg.C-type, a constant type sensor 70 deg.C-type, a differential type sensor 1 type, a differential type sensor 2 type and the like, for example in accordance with a measured result.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a fire detector used for a fire alarm device.

[0002]

2. Description of the Related Art Most conventional fire detectors, both heat detectors and smoke detectors, have a sensor unit and a signal processing unit housed in a single housing and mounted on a ceiling or the like. However, in each dwelling unit such as an apartment house, a fire detector is often installed in each room, and having a signal processing unit for each fire detector has a problem in terms of cost. The applicant previously filed a patent application as Japanese Patent Application No. 8-350896 with respect to a fire detector separately provided from the fire detector. This prior application includes a plurality of temperature detection units and a signal processing unit that performs signal processing of these temperature detection units, and outputs a fire detection signal based on any one or a plurality of temperature values. Is a fire detector that detects the room temperature in a number of sensing areas.

[0003]

However, in the above-mentioned prior application, since each sensor unit cannot determine the type of the fire detector, that is, the constant temperature type, the differential type, or the sensitivity within the type, it is difficult to determine the type of the fire detector. It is necessary to use one type or sensitivity or to set the type or sensitivity for each sensor unit in the signal processing unit.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to provide a fire detector for separating a sensor unit and a signal processing unit. It is an object of the present invention to provide a fire detector capable of automatically determining the sensitivity and sensitivity by a signal processing unit.

[0005]

According to the first aspect of the present invention, there is provided a fire detector for detecting an increase in room temperature, wherein a signal processing unit and a sensor unit are powered by a power supply. In addition to being separately disposed via a signal line, the sensor unit has a thermistor having a temperature resistance value characteristic that differs depending on the type or sensitivity of the fire detector, and the signal processing unit measures the resistance value characteristic at room temperature. Thus, the type or sensitivity of the thermistor is determined and set.

According to a second aspect of the present invention, there is provided a fire detector for detecting an increase in room temperature, wherein a signal processing unit and a sensor unit are separately provided via a power / signal line.
The sensor unit has a thermistor having a temperature resistance value characteristic that differs depending on the type or sensitivity of the fire detector, and the thermistor has a temperature resistance value characteristic in which the temperature resistance characteristics do not overlap each other between different types or sensitivities, and signal processing is performed. The type or sensitivity of the thermistor is determined and set by measuring the resistance value characteristics in the section.

According to a third aspect of the present invention, there is provided a fire detector for detecting a rise in room temperature, wherein a signal processing unit and a sensor unit are separately disposed via a power / signal line.
The sensor unit has a thermistor having a temperature resistance value characteristic that differs depending on the type or sensitivity of the fire detector, and a thermistor that connects a diode in series and a thermistor that is not connected are provided, and the polarity of the current supplied to the sensor unit is changed. By switching, the type or sensitivity of the thermistor is determined and set in the signal processing unit.

According to a fourth aspect of the present invention, there is provided a fire detector for detecting a rise in room temperature, wherein a signal processing unit and a sensor unit are separately provided via a power / signal line.
The sensor unit has a thermistor having a temperature resistance value characteristic that differs depending on the type or sensitivity of the fire detector, and a thermistor that connects a capacitor in parallel and a thermistor that is not connected are provided. , The type or sensitivity of the thermistor is determined and set in the signal processing unit.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a first embodiment of a fire detector according to the present invention will be described.
The first embodiment will be described with reference to FIGS. 1 to 4, the second embodiment will be described with reference to FIGS. 5 to 7, and the third embodiment will be described with reference to FIGS. .

[First Embodiment] FIG. 1 is a block diagram of a fire detector according to a first embodiment, FIG. 2 is a diagram showing a temperature resistance characteristic of a thermistor, and FIG. 3 is a temperature of another thermistor. FIG. 4 is a diagram showing a resistance value characteristic, and FIG. 4 is a diagram showing a temperature resistance value characteristic of another thermistor.

As shown in FIG. 1, the fire detector has a signal processing unit 1 and a sensor unit 2, and the sensor unit 2 is connected to a receiver (not shown). The signal processing unit 1 and the sensor unit 2 are connected via a power / signal line L, and the signal processing unit 1 and the sensor unit 2 are disposed separately. When the fire detector is installed in each dwelling unit of the apartment house, the signal processing unit 1 can be installed in the housing information panel or the distribution board of each dwelling unit, or can be installed near the entrance of the dwelling unit. The sensor unit 2 can be installed in a kitchen or each room.

The sensor section 2 comprises a thermistor 3 and is connected to the signal processing section 1 by a power / signal line L. The thermistor 3 converts a change in temperature such as room temperature into a change in resistance. The thermistor 3 has a plurality of different temperature resistance characteristics selected and connected, and includes a constant temperature sensor, a differential sensor, or a sensitivity type for each of the types.
For example, constant temperature sensor 60 ° C type, constant temperature sensor 70 ° C
It has temperature resistance value characteristics corresponding to the type, one type of differential sensor, two types of differential sensor, and the like.

On the other hand, the signal processing unit 1
And a fire signal circuit 11 and a type determination circuit 12. The type determination circuit 12 applies a direct current to the sensor unit 2 during normal monitoring. When the fire detector is installed, the resistance of the thermistor 3 is measured. According to the measurement result, the connected thermistor 3 is a constant temperature sensor, a differential sensor, or a sensitivity type for each type as the fire detector, for example, a constant temperature sensor 60 ° C. type, a constant temperature type. Discrimination of 70 ° C. type sensor, one type of differential type sensor, two types of differential type sensor, etc. is performed.

Next, an example of the temperature resistance characteristic of each thermistor 3 will be described with reference to FIGS. FIG. 2 is an example of a temperature resistance value characteristic of a constant temperature sensor and a temperature resistance value characteristic of a differential sensor. Two thermistors 3 are selected such that the constant-temperature sensor has a higher resistance at room temperature and the differential sensor has a lower resistance at room temperature.

By measuring the resistance value at room temperature in the type determination circuit 12 of the signal processing section 1, the signal processing section 1 can determine and store the sensor type of the connected thermistor 3. .

FIG. 3 shows an example of the temperature resistance characteristics of another constant temperature sensor and the temperature resistance characteristics of a differential sensor. The resistance value of the differential sensor is set higher at room temperature, and the resistance value of the constant temperature sensor is set lower at room temperature.

As in the case of FIG. 2, the type discriminating circuit 12 of the signal processing unit 1 measures the resistance value at room temperature, so that the connected thermistor 3 is connected to the signal processing unit 1.
Can be determined and stored.

FIG. 4 shows that the temperature resistance characteristics of the constant temperature sensor and the differential sensor do not overlap each other at all temperatures in the operating temperature range. By setting the temperature resistance characteristics in this way, even if the actual temperature of the place where each of the thermistors 3 is installed is greatly different when the fire detector is installed, the temperature resistance characteristics can be measured. By doing so, the type can be identified.

[Second Embodiment] FIG. 5 is a block diagram of a fire detector according to a second embodiment, FIG. 6 is a diagram showing an example in which a diode is connected to a sensor unit, and FIG. It is a figure showing other examples which connected a diode.

The sensor section 2 is formed by a thermistor 3 and a diode 4. The thermistor 3 and the diode 4 are connected in series to the signal processing section 1 by a power / signal line L. The thermistor 3 converts a change in temperature such as room temperature into a change in resistance. As shown in FIGS. 6 and 7, if the diode 4 is a forward current, a current flows.

On the other hand, the signal processing unit 1
And a fire signal circuit 11, a type determination circuit 12, and a polarity inversion circuit 13.

The polarity inversion circuit 13 applies a DC current to the sensor unit 2 during normal monitoring, and inverts the polarity of the voltage supply to the thermistor 3 when the fire detector is installed. Supply. In the case of FIG. 6, if a current flows at this time, the type detection circuit 12 determines that the sensor is a constant temperature sensor, and if no current flows, the sensor is a differential sensor. Is that each thermistor 3 determines a fire as a constant temperature sensor and a differential sensor, respectively.

FIG. 7 shows, for example, whether the constant-temperature sensor 60 ° C. type or the constant-temperature sensor 70 ° C. type is discriminated by the polarity inversion circuit 13 according to whether or not the diode 4 is connected to the thermistor 3. This is an example performed in the determination circuit 12.

Third Embodiment FIG. 8 is a block diagram of a fire detector according to a third embodiment, FIG. 9 is a diagram showing an example in which a capacitor is connected to a sensor unit, and FIG. It is a figure showing other examples to which a capacitor was connected.

As shown in FIG. 9 and FIG. 10, the sensor unit 2 is prepared by forming the thermistor 3 and the capacitor 5 and not connecting the capacitor 5. The thermistor 3 and the capacitor 5 are connected to the signal processing unit 1 by a power / signal line L.
Are connected in parallel. The thermistor 3 converts a change in temperature such as room temperature into a change in resistance.

On the other hand, the signal processing unit 1
And a fire signal circuit 11, a type determination circuit 12, and a switching circuit 14.

The switching circuit 14 applies a direct current to the sensor unit 2 during normal monitoring, and interrupts the supply of voltage to the thermistor 3 (ON, OFF) when this fire detector is installed. Off) and supply. At this time, a current also flows through the capacitor 5 and the total current with the thermistor 3 is measured to determine the constant-temperature sensor.
The type discriminating circuit 12 discriminates, and thereafter, with the setting, the temperature detecting circuit 10 determines that each thermistor 3 determines a fire as a constant temperature sensor and a differential sensor, respectively.

FIG. 10 shows each thermistor 3.
In this example, the switching circuit 14 and the type determination circuit 12 determine, for example, one type of differential sensor and two types of differential type sensors depending on whether or not the capacitor 5 is connected to the switching circuit 14.

[0029]

According to the first aspect of the present invention, in the fire detector in which the signal processing unit and the sensor unit are separated,
This has the effect that the signal processing unit can determine the sensor type and the sensitivity type.

According to the second aspect of the present invention, in the fire detector in which the signal processing unit and the sensor unit are separated, the signal processing unit can determine the type of the sensor and the sensitivity type. There is an effect that the determination can be made even if the temperature is not room temperature.

According to the third aspect of the present invention, in the fire detector in which the signal processing unit and the sensor unit are separated, the type and sensitivity of the sensor are determined by whether or not the diode is connected to the sensor unit in the signal processing unit. There is an effect that the type can be determined.

According to the fourth aspect of the present invention, in the fire detector in which the signal processing unit and the sensor unit are separated, the type and sensitivity of the sensor are determined by whether or not a capacitor is connected to the sensor unit in the signal processing unit. There is an effect that the type can be determined.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a fire detector according to a first embodiment of the present invention.

FIG. 2 is a diagram illustrating temperature resistance characteristics of a thermistor;

FIG. 3 is a diagram illustrating another example of a temperature resistance value characteristic of a thermistor.

FIG. 4 is a diagram showing another example of the temperature resistance value characteristic of the thermistor.

FIG. 5 is a block diagram of a fire detector according to a second embodiment.

FIG. 6 is a diagram illustrating an example in which a diode is connected to a sensor unit.

FIG. 7 is a diagram illustrating an example in which a diode is connected to a sensor unit.

FIG. 8 is a block diagram of a fire detector according to a third embodiment.

FIG. 9 is a diagram illustrating an example in which a capacitor is connected to a sensor unit.

FIG. 10 is a diagram illustrating an example in which a capacitor is connected to a sensor unit.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Signal processing part 2 Sensor part 3 Thermistor 4 Diode 5 Capacitor 12 Type discrimination circuit 13 Polarity inversion circuit 14 Switching circuit L Power supply and signal line

Claims (4)

[Claims] 1. A fire detector for detecting a rise in room temperature, wherein a signal processing unit and a sensor unit are separately arranged via a power / signal line, and the sensor unit includes a fire detector type or A fire detector comprising a thermistor having a temperature resistance value characteristic that varies depending on sensitivity, and determining and setting the type or sensitivity of the thermistor by measuring a resistance value characteristic at room temperature by a signal processing unit. 2. A fire detector for detecting an increase in room temperature, wherein a signal processing unit and a sensor unit are separately provided via a power / signal line, and the type of the fire detector or By having a thermistor having a temperature resistance characteristic that varies depending on the sensitivity, and the thermistor has a temperature resistance characteristic in which the temperature resistance characteristics do not overlap each other between different types or sensitivities, and measures the resistance characteristic in a signal processing unit. A fire detector characterized in that the type or sensitivity of the thermistor is determined and set. 3. A fire detector for detecting an increase in room temperature, wherein a signal processing unit and a sensor unit are separately disposed via a power / signal line, and the sensor unit includes a fire detector type or It has thermistors having different temperature resistance characteristics depending on the sensitivity, and a thermistor that connects a diode in series and a thermistor that is not connected are provided, and the polarity of the current supplied to the sensor unit is switched. A fire detector characterized by determining and setting the sensitivity. 4. A fire detector for detecting an increase in room temperature, wherein a signal processing unit and a sensor unit are separately provided via a power / signal line, and the type of the fire detector or A thermistor having a temperature resistance characteristic that varies depending on the sensitivity, a thermistor that connects a capacitor in parallel, and a thermistor that is not connected are provided. A fire detector characterized in that the type or sensitivity is determined and set.