JPH0381899A - Fire sensor - Google Patents

Abstract

PURPOSE:To previously prevent the generation of misinformation, etc., and to improve the performance of the fire sensor by monitoring the current consumption of a fire detecting part and judging the abnormality of the fire sensor from the current change. CONSTITUTION:When fire occurs, a fire detector FD detects the fire, a switching circuit SC is excited, a large current ID flows, and voltage Vi is further reduced as compared to a short-circuit failure in a fire detection part DE. When the voltage Vi is dropped less than the reference voltage V3 of the 3rd comparator CM3, its output is inverted and a signal indicating fire abnormal generation is outputted. Thereby, the value of the voltage Vi in the normal state is set up between the 1st and 2nd reference voltages V1, V2, so that the abnormal state can be discriminated d from fire information by setting up V1>Vi>V2> V3.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a fire detector in a fire alarm system, and in particular, to a fire detection section for detecting a physical quantity based on a fire phenomenon, and a structure in which the fire detection section is detachable. The present invention relates to a fire detector including a signal conversion section that is freely attached and supplies power to the fire detection section when attached.

[Background of the Invention] For example, in Japanese Utility Model Publication No. 59-37912 filed by the present applicant, a non-storage type sensor and a fire receiver are disclosed in order to use the non-storage type sensor as a storage type sensor as needed. It is disclosed that a removable adapter for non-storage-to-storage conversion is used between the line leading to the .

Also, Japanese Patent Application No. 1-163670 filed by the applicant on June 29, 1999, and July 11, 1999.
Japanese Patent Application No. 1-177098, filed in 1999, describes a method for wirelessly transmitting signals between each fire detector and a receiving section such as a fire receiver using an optical signal or the like. Consists of a fire detection section that detects fire, and a sensor adapter as a signal conversion section with a built-in power supply for attaching the fire detection section, and the detector adapter supplies power to the fire detection section from the built-in power supply. In addition, a wireless fire alarm system is shown in which when a fire signal or an abnormal signal is received from a fire detection section, a detector adapter converts it into an optical signal and transmits it to a fire receiver, etc. through space. ing.

[Problems to be Solved by the Invention] Fire detectors constantly monitor fires 24 hours a day.
(detector adapter) and a fire detection section that is electrically connected to the signal conversion section by a socket, etc., in the event of an abnormality such as a failure of the sensor circuit of the fire detection section or poor contact of the socket, It is necessary to notify the fire receiver of the abnormality of the fire detector as soon as possible and take measures such as replacing the fire detector.

Therefore, an object of the present invention is to provide a fire detector that can notify a receiving unit such as a fire receiver not only of a fire abnormality but also of an abnormality of the fire detector itself, when configured by a fire detection unit and an adapter. It is intended to provide
In particular, as in the wireless fire alarm system described in the above-mentioned patent application, signal transmission between a fire receiver or the like and a fire detector is performed over a space using coded light, radio waves, etc. It is intended to be suitably used when the tests are conducted separately.

[Means for Solving the Problems] Specifically, according to the present invention, there is provided a fire detection unit for detecting a physical quantity based on a fire phenomenon, and a fire detection unit that is removably attached so that the fire detection unit detects a physical quantity based on a fire phenomenon. A fire detector comprising: a signal conversion section that supplies power to the fire detection section, the signal conversion section comprising: current detection means for detecting the current supplied to the fire detection section; first current monitoring means that monitors the current detected by the detection means and outputs a signal indicating an abnormality of the fire detector when the current supplied to the fire detection section deviates from a predetermined range indicating a normal state; and a second current that monitors the current detected by the current detection means and outputs a fire abnormality occurrence signal when the current supplied to the fire detection section reaches a reference value representing a fire abnormality occurrence state. monitoring means; and code generation means for generating a code signal corresponding to the fire detector abnormality signal from the first current monitoring means or the fire abnormality occurrence signal from the second current monitoring means. A fire detector is provided.

Further, according to the present invention, there is provided a fire detection section that operates intermittently to detect a physical quantity based on a fire phenomenon, and a fire detection section that is removably attached and that supplies power to the fire detection section when attached. A fire detector comprising: a signal converter for detecting a current, the signal converter comprising: current detecting means for detecting a current supplied to the fire detecting section; A first current monitoring means that monitors intermittent current based on intermittent operation of the fire detector, and outputs a signal indicating an abnormality of the fire detector when the frequency or amplitude of the intermittent current decreases beyond a reference value. and a second current that monitors the current detected by the current detection means and outputs a fire abnormality occurrence signal when the current supplied to the fire detection section reaches a reference value representing a fire abnormality occurrence state. monitoring means; and code generation means for generating a code signal corresponding to the fire detector abnormality signal from the first current monitoring means or the fire abnormality occurrence signal from the second current monitoring means. A fire detector is provided.

[Operation] In this way, the current consumption in the fire detection section is constantly monitored, and various abnormalities in the fire detector are determined from changes in its state. Therefore, false alarms due to sensor abnormalities can be prevented.

[Example] This will be explained below based on the figures.

FIG. 1 is a circuit diagram showing a fire detector operated by battery B, for explaining one embodiment of the present invention. A signal conversion device STD is shown.

The fire detection unit DE includes a fire detection circuit FD for detecting a physical quantity based on a fire phenomenon, and a signal conversion device S that is energized when the fire detection circuit FD detects a predetermined amount of physical quantity.
It consists of a switching circuit SC that outputs a fire signal to the TD.

In addition, the signal conversion unit fisTD is roughly equivalent to the fire detection unit DE.
■ Current consumption flowing to the side. a resistor R1 for detecting;
The current consumption is due to the voltage drop of the resistor R3. first, second, and third comparators CM that detect a change in and determine a contact failure between the fire detection unit DE and the signal conversion device STD, a failure of the fire detection unit DE, and the occurrence of a fire abnormality, respectively; , C
M2, CM.

, a code generation circuit CG that generates a coded signal according to the output of each comparator, and a light emitting diode L that sends a coded signal to a fire receiver (not shown) according to the output of the code generation circuit CG. It is configured.

Next, the operation will be explained.

First, second, and third comparators CM, CM2, CM,
The voltage V input to the child terminal, one terminal, and one terminal, respectively
Since I is the value obtained by subtracting the voltage drop V8 due to the resistor R1 from the power supply voltage E, it decreases as the current Io increases.

A disconnection failure in the fire detection unit DE, including a disconnection failure in the fire detection circuit FD, or a socket contact failure, that is, a contact failure at the joint between the fire detection unit DE and the signal conversion device STD, as indicated by line l, may occur. If the current is 1. either does not flow or is greatly reduced, and the voltage VI becomes large. Therefore, in order to detect this, a first reference voltage Vl is set at one terminal of the first comparator CMI. As a result, when the voltage V becomes equal to or higher than the first reference voltage V3, the first
The output of the comparator CM is inverted from a low potential to a high potential, and a signal indicating that the above-mentioned disconnection failure or socket contact failure has occurred is output.

Conversely, due to a short-circuit failure in the fire detection section DE, the current I
When o increases, voltage V1 decreases. Therefore,
In order to detect this, a second reference voltage V2 is set at the child terminal of the second comparator CM. As a result, the voltage V
When l becomes lower than the second reference voltage v2, the output of the second comparator CM is inverted from a low potential to a high potential,
A signal indicating a failure such as a short circuit is output.

When a fire occurs, the switching circuit SC is energized and a large current ■. flows, and the voltage V is even smaller than in the case of a short-circuit failure at the fire inspection station DE. Therefore, in order to detect this, a third reference voltage V is set at the middle terminal of the third comparator CM.
The reference voltage V.

When the voltage is below, the output of the third comparator CM3 is inverted from a low potential to a high potential, and a signal indicating the occurrence of a fire abnormality is output.

When the fire detector is monitoring under normal conditions with no abnormalities occurring, the current consumption is 1. is fire detection part D
It is substantially equal to the current consumed by E, and has an approximately constant value. Therefore, the value of voltage Vi in a normal state is between the first and second reference voltages V1 and V2. , V +
> V l > V 2 > V 3. By setting the reference voltage in this way, it is possible to distinguish between an abnormal state of the fire detector and a fire alarm.

If a failure occurs in the fire detection unit, such as a break in the fire detection unit, a short-circuit failure, or a socket contact failure, a high potential is detected from either the first or second comparator CM or CM2. A signal is output, and the high potential signal is applied to the terminal of the code generation circuit CG via the OR circuit OR and one terminal of the AND circuit A N D +.

This is because the other terminal of the AND circuit A N D + is connected to the third comparator CM via the inverter I N V l.
This is because the gate of the AND circuit ANDI is open when no fire has occurred since the inverted signal of the output of No. 3 is provided. The code generation circuit CG is connected to the terminal ■
When a high potential signal is input to the terminal, a coded signal indicating the occurrence of a failure or an abnormality is output from the terminal ■, and the coded signal is converted into an optical signal by the light emitting diode L via the transistor Q, and is spatially transmitted. Alternatively, it is sent wirelessly to a fire receiver, etc.

On the other hand, when a fire occurs, the switching circuit SC operates, so the current consumption I0 reaches its maximum, which causes the voltage V,
becomes smaller than the third reference voltage V, and the output of the third comparator CM is inverted from a low potential to a high potential, and the high potential signal output is applied to the code generation circuit CG at the terminal (2).

When a high potential signal is input to the terminal (2), the code generation circuit CG outputs a coded signal indicating the occurrence of a fire from the terminal (2), and the coded signal is converted into an optical signal by the light emitting diode L via the transistor Q. It is converted and sent to a fire receiver, etc. via space transmission or wirelessly.

Note that at this time, the voltage V is the third reference voltage V.

The second comparator CM by being smaller than CM.

is also inverted and outputs a high potential signal, but the third comparator CM
, is inverted by the inverters I, NV, and applied to the other terminal of the AND circuit AN D +, thereby closing the gate of the AND circuit ANDI, and therefore, the second comparator CM2 The high potential signal output is not applied to the terminal of the code generation circuit CG.

Furthermore, in this embodiment, the relationship between the first to third reference voltages is V + > V 2 > V 3; In the case of less, VI〉V, >V,
You should choose so that.

Next, another embodiment of the present invention will be described based on FIG.

For example, in photoelectric smoke detectors and the like, in order to reduce current consumption during monitoring, a light source for detecting smoke is caused to emit light intermittently. In such a fire detector, the current consumption during monitoring has a pulse waveform as shown in FIG. 3. This embodiment attempts to detect an abnormality in the fire detector by detecting this pulse current. be.

In FIG. 2, the same parts as in FIG. 1 are designated by the same reference numerals.

When monitoring a fire, the fire detection circuit FD causes its built-in light source to emit light intermittently, so that a pulse voltage having a waveform as shown in FIG. 3 is generated across the current detection resistor R1.

When the fire detection unit DE is normal, a pulse voltage across the resistor R1 is applied to the base of the transistor Q2 via the capacitor C1 and the resistor R, making the transistor Q2 conductive, thereby producing a pulse at its collector. A voltage is generated, and this pulse voltage is applied to the reset terminal R of the timer circuit TC as a reset input. timer circuit TC
is a device that outputs a high potential signal when the time is up when a predetermined set time is counted, but it is reset every time a reset input is received at the terminal R, and the counting of the predetermined set time is restarted from the beginning. Melt. The predetermined set time counted by the timer circuit TC is set longer than the period T of the pulse voltage generated by the transistor Q2, and therefore,
As long as transistor Q2 is generating a pulse voltage, timer circuit TC will not output a high potential signal.

If the light source in the fire detection circuit FD stops emitting light due to a disconnection, etc., or if the pulse current flowing through the resistor R3 decreases beyond the limit due to a poor contact in the socket, etc., the transistor Q2 ceases to conduct, and the timer circuit TC A reset signal is no longer applied to the reset terminal R of the circuit, and as a result, a high potential signal is outputted from the timer circuit TC to the terminal (2) of the code generation circuit CG after a predetermined set time has elapsed.

When the high potential signal is received at the terminal ■, the code generating circuit CG transmits a coded optical signal indicating an abnormality in the fire detector from the light emitting diode L to the fire receiver (not shown) in the manner described in FIG. Send it to a machine, etc.

In addition, when a fire occurs, when the fire detection circuit FD detects the occurrence of a fire and the switching circuit SC is energized, the current ■. Since the current flows continuously, a continuous voltage drop occurs across the resistor R1.

The continuous voltage drop is applied to the base of transistor Q2 through resistor R1, rendering transistor Q continuously conductive. When the transistor Q2 becomes continuously conductive, the voltage from the power supply is applied as a high potential signal to the terminal 2 of the code generation circuit CG through the integrator circuit formed by the resistor R1 and the capacitor C1, and the code generation circuit C
G transmits a coded optical signal indicating the occurrence of a fire abnormality from the light emitting diode L to a fire receiver or the like in the manner described in FIG.

In this case, the reset input remains applied to the reset terminal R of the timer circuit TC, and the timer circuit TC does not output a high potential signal.

Also, the purpose of the integrating circuit, which requires resistor R9 and capacitor C9, is that during normal fire monitoring in fire detection section DE, the pulse voltage generated at the collector of transistor Q2 is input to the terminal ■ of the code generation circuit. The object of this invention is to prevent a false fire abnormality occurrence signal from being sent out.

[Effects of the Invention] As described above, according to the present invention, in a fire detector in which the fire detection section is attached to an adapter or the like, the current consumption in the fire detection section is constantly monitored, so that changes in the current can be detected. It is now possible to detect abnormalities in the fire detector, such as improper installation. Therefore, it is possible to prevent false alarms caused by sensor abnormalities, and it is possible to obtain a fire detector with high performance.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram showing a fire detector according to one embodiment of the present invention, FIG. 2 is a circuit diagram showing another embodiment of the present invention, and FIG.
0 is a waveform diagram used to explain the operation of FIG. 2, DE is a fire detection section, STD is a signal conversion section, R1 is a current detection resistor, FD is a fire detection circuit,
SC is a switching circuit, CG is a code generation circuit, L is a light emitting diode, B is a battery, CM, CM2, CM
. are first, second and third comparators, respectively, and TC is a timer circuit.

Claims (2)

[Claims] (1) A fire detection unit that includes a fire detection unit for detecting a physical quantity based on a fire phenomenon, and a signal conversion unit to which the fire detection unit is detachably attached and which supplies power to the fire detection unit when attached. The signal conversion unit includes: current detection means for detecting the current supplied to the fire detection unit; and current detection means for monitoring the current detected by the current detection unit and detecting the current supplied to the fire detection unit. a first current monitoring means that outputs a signal indicating an abnormality of the fire detector when the current detected by the current detecting device deviates from a predetermined range representing a normal state; second current monitoring means for outputting a fire abnormality occurrence signal when the current supplied to the section reaches a reference value representing a fire abnormality occurrence state; and a second current monitoring means for outputting a fire abnormality occurrence signal from the first current monitoring means; A fire detector comprising: code generating means for generating a signal or a code signal corresponding to the fire abnormality occurrence signal from the second current monitoring means. (2) A fire detection section that operates intermittently to detect physical quantities based on fire phenomena; and a signal conversion section that is removably attached to the fire detection section and supplies power to the fire detection section when attached. , wherein the signal conversion section includes: current detection means for detecting the current supplied to the fire detection section; and current detection means for detecting the current supplied to the fire detection section; a first current monitoring means that monitors an intermittent current based on intermittent operation and outputs a signal indicating an abnormality of the fire detector when the frequency or amplitude of the intermittent current decreases beyond a reference value; a second current monitoring means for monitoring the current detected by the means and outputting a fire abnormality occurrence signal when the current supplied to the fire detection section reaches a reference value representing a fire abnormality occurrence state; Code generation means for generating a code signal corresponding to the fire sensor abnormality signal from the first current monitoring means or the fire abnormality occurrence signal from the second current monitoring means. fire detector.