JP3114132B2 - Photoelectric separated smoke detector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
The present invention relates to a photoelectric separation type smoke detector which is installed at a distance of several hundred meters away from each other, and more particularly to power supply control of a light reception level display circuit.

[0002]

2. Description of the Related Art FIG. 3 is a circuit diagram showing the electrical connection of a conventional photoelectric separation type smoke detector. In the figure, RE is a fire receiver, 1 is a light transmitting section for transmitting, for example, near infrared light of a photoelectric separation type smoke detector, and 2 is several meters to several 1 facing the light transmitting section 1.
It is a light receiving unit of a photoelectric separation type smoke sensor which is installed at a distance of 00 m and receives light transmitted from the light transmitting unit 1. Reference numeral 3 denotes a pair of power / signal lines for connecting the light receiving unit 2 and the fire receiver RE. Reference numeral 4 denotes a power supply line for supplying power from the light receiving unit 2 to the light transmitting unit 1. Reference numeral 5 denotes a light transmitting unit 1 to the light transmitting unit 1. Is a signal line for transmitting a light emission command signal, 6 is a bipolar or monaural plug, and 7 is a level adjusting voltmeter connected to the plug 6.

[0003] Reference numeral 11 denotes a light emitting diode which is a smoke detecting light emitting element for transmitting light from the light emitting unit 1, and 12 denotes a light emitting control circuit which controls light emission of the light emitting diode 11 when a light emitting command signal is received.

[0004] Reference numeral 21 denotes a photodiode which is a light detector for smoke detection which receives light transmitted from the light emitting diode 11, 22 denotes a light receiving amplifier constituted by a filter circuit for amplifying a light receiving output voltage of the photodiode 21, an operational amplifier and the like. A sample-and-hold circuit 23 for temporarily holding the light-receiving output output from the light-receiving amplifier circuit 22;
Is a microcomputer constituting a fire determining circuit for determining whether or not there is a fire based on the received light output held by the sample and hold circuit 23. The microcomputer includes an A / D converter and a D / A.
Built-in converter. IN1 to IN4 are input ports, and OUT1 to OUT3 are output ports. 25 is a sending circuit for sending a light emission command signal to the light emission control circuit 12;
Reference numeral 7 denotes a light receiving level display circuit that converts a light receiving level output from the microcomputer 24 into a driving voltage of the level adjusting voltmeter 7 and outputs the driving voltage. 28 denotes a serial-parallel converter that receives a call signal from the fire receiver RE and the like A transmission circuit for transmitting a fire signal or the like to the fire receiver RE; a constant voltage circuit for supplying a voltage necessary for each circuit in the light receiving unit 2 and the light emitting unit 1; Reference numeral 43 denotes an interlocking changeover switch for setting a distance corresponding to a three-step distance;
Reference numeral 4 denotes a volume which is a level adjuster for adjusting the level of the light reception output of the photodiode 21, and reference numeral 45 denotes a bipolar or monaural jack constituting an output terminal of the light reception level display circuit 27.

[0005] The conventional photoelectric separation type smoke detector is constructed as described above.
Sends a light emission command signal to the light transmitting unit 1 via the transmission circuit 25 every three seconds, and in the light transmitting unit 1, the light emission control circuit 12 causes the light emitting diode 11 to emit light.

The light receiving section 2 is a light emitting diode 11 of the light transmitting section 1.
When light from the photodiode 21 is received by the photodiode 21, the received light output of the analog signal of the photodiode 21 is amplified by the light receiving amplifier circuit 22, and the received light output is held by the sample hold circuit 23. The received light output of the analog signal held by the sample-and-hold circuit 23 is read into the microcomputer 24, digitized by the built-in A / D converter, and compared with a fire discrimination value. Output from the output port OUT3. The fire signal is transmitted to the fire receiver RE via the transmission circuit 29. At the same time, the digitized light receiving output is converted into an analog signal by a built-in D / A converter and is input to the light receiving level display circuit 27 from the output port OUT2.

In the meantime, in the photoelectric separation type smoke detector, the light transmitting unit 1 and the light receiving unit 2 are opposed to each other at a distance of several meters to several hundred meters according to the size of the fire monitoring area (space). At the time of periodic inspection, etc., it is necessary to adjust the level of the light receiving output of the light receiving element in accordance with the facing distance for each installation site. This level adjustment is performed as follows at the time of installation, for example. First,
The interlock changeover switches 41 to 43 provided in the light receiving unit 2 and can be switched in three stages according to the distance are switched to a range including the facing distance. As a result, the level of the light receiving and amplifying circuit 22 is selected, for example, from among the distances, a level suitable for an intermediate distance. At this time, the level does not always correspond to the actual opposing distance.

Next, the plug 6 to which the level adjusting voltmeter 7 is connected is inserted into the jack 45 of the light receiving section 2. As a result, the output of the light receiving level display circuit 27 is input to the level adjusting voltmeter 7 via the jack 45 and the plug 6. Therefore, the volume 44 is adjusted so that the voltmeter 7 indicates a predetermined voltage value, for example, 7 V, and when the level adjustment is completed, the plug 6 is pulled out from the jack 45.

[0009]

In the above-mentioned conventional photoelectric separation type smoke detector, the level adjustment used for performing the level adjustment suitable for the facing distance between the light transmitting unit 1 and the light receiving unit 2 is performed. Level display circuit 2 for driving voltmeter 7
7 is provided in the light receiving section 2 and its light receiving level display circuit 27 is connected so that power is always supplied to the constant voltage circuit 30. Therefore, the plug 6 connected to the level adjusting voltmeter 7 is provided. Is not inserted into the bipolar jack 45 constituting the output terminal of the light reception level display circuit 27, the light reception level display circuit 27 is in the operating state,
There is a problem that current is always consumed and uneconomical.

The present invention has been made to solve such a problem. When a level adjusting voltmeter is connected to a light receiving level display circuit of a light receiving section, power is automatically supplied to the light receiving level display circuit. When the connection between the voltmeter for level adjustment and the light reception level display circuit is disconnected, the power supply to the light reception level display circuit is automatically cut off, so that the light reception level display circuit other than during the level adjustment is used. An object of the present invention is to obtain a photoelectric separation type smoke detector that can reduce current consumption.

[0011]

According to the present invention, there is provided a photoelectric separation type smoke detector according to the present invention, in which a light receiving section is provided with a three-pole jack into which a two-pole plug connected to an instrument for level adjustment is inserted. One terminal of the positive terminal is connected to the output terminal of the light receiving level display circuit, the other terminal of the positive terminal of the jack is connected to the power supply negative terminal of the light receiving level display circuit, and the negative terminal of the jack is connected to the negative terminal of the constant voltage circuit. The positive terminal of the constant voltage circuit is connected to the power supply positive terminal of the light receiving level display circuit.

[0012]

According to the present invention, when a level adjusting instrument is inserted into a three-pole type jack provided in the light receiving portion, one of the positive terminals of the jack connected to the output terminal of the light receiving level display circuit 27 is connected. Connected to a level adjustment instrument via a plug. At the same time, the other terminal of the positive terminal of the jack connected to the power supply negative terminal of the light reception level display circuit is connected to the negative terminal of the jack connected to the negative terminal of the constant voltage circuit via a plug. Since the plus terminal of the circuit is always connected to the power supply plus terminal of the light reception level display circuit, the power of the constant voltage circuit is supplied to the light reception level display circuit, and the light reception level display circuit starts operating.

When the plug is pulled out of the jack,
The connection between the jack terminals is broken, the connection between the power supply negative terminal of the light receiving level display circuit and the negative terminal of the constant voltage circuit is lost, and the power supply to the light receiving level display circuit by the constant voltage circuit is cut off.

[0014]

FIG. 1 is a circuit diagram showing an electrical connection according to an embodiment of the present invention, and FIG. 2 is a circuit diagram showing an electrical connection of a main part of the embodiment, in which a plug is pulled out. In the figure, the same components as those of the conventional example are denoted by the same reference numerals as those of the conventional example, and the description of the same components is omitted. 26 is a sample and hold circuit for temporarily holding the light receiving level of the analog signal output from the output port OUT2 of the microcomputer 24 and outputting the held light receiving level to the light receiving level display circuit 27; A power supply switch which is a switching element such as a transistor or an analog switch provided between the power supply minus terminal 22a and the ground. The power supply switch 31 is a control signal output from an output port OUT4 of the microcomputer 24. On / off control. Reference numeral 55 denotes a three-pole or stereo jack constituting an output terminal of the light receiving level display circuit 27. One terminal 55 a of the positive electrode of the jack 55 is connected to the output terminal of the light receiving level display circuit 27. The other positive terminal 55a of the jack 55 is connected to the power supply negative terminal 27b of the light receiving level display circuit 27 and the power supply negative terminal 26b of the sample hold circuit 26. Further, the negative terminal 55c of the jack 55 is connected to the ground,
The negative terminal 30b of the constant voltage circuit 30 is also connected to the ground. The positive terminal 30a of the constant voltage circuit 30
Are connected to the power supply plus terminal 27a of the light reception level display circuit 27 and the power supply plus terminal 26a of the sample hold circuit 26. The plug 6 inserted into the jack 55 is the same as that of the conventional example.

In the photoelectric separation type smoke detector configured as described above, the operation of the microcomputer 24 at the time of fire monitoring is such that the microcomputer 24 supplies power, for example, 1 ms before the emission command signal is transmitted to the transmission circuit 25. The switch 31 is turned on to activate the light receiving and amplifying circuit 22 having a plurality of operational amplifiers, and after the light receiving output of the light receiving and amplifying circuit 22 is held by the sample and hold circuit 23, for example, after a light emission command signal is transmitted. Power supply switch 3 after 1 ms
The microcomputer 24 does not constantly output the analog signal of the light receiving level by keeping the sample and hold circuit 26 to hold the light receiving level of the analog signal output from the microcomputer 24 in that the power consumption is suppressed by turning off the microcomputer 1. Except for the improvement, the configuration is the same as that of the conventional example, so that the description thereof will be omitted, and the operation of level adjustment at the time of installation will be described.

First, the interlocking changeover switches 41 to 43 are switched to positions corresponding to the distance between the light transmitting unit 1 and the light receiving unit 2, and the level adjusting voltmeter 7 is connected to the jack 55 of the light receiving unit 2. Plug 6 is inserted. Thereby, one terminal 55 a of the positive electrode of the jack 55 connected to the output terminal of the light receiving level display circuit 27 is connected to the level adjusting voltmeter 7 via the positive electrode 6 a of the plug 6. At the same time, the other positive terminal 55b of the jack 55 connected to the power minus terminal 27b of the light receiving level display circuit 27 and the power minus terminal 26b of the sample hold circuit 26 is connected to the constant voltage circuit via the negative terminal 6b of the plug 6. 30 is connected to the negative terminal 55c of the jack 55 substantially connected to the minus terminal 30b. The plus terminal 30a of the constant voltage circuit 30, the plus power terminal 27a of the light receiving level display circuit 27, and the plus power terminal 26a of the sample and hold circuit 26 are always connected. Accordingly, the plus terminal and the minus terminals 30a, 30b of the constant voltage circuit 30 are connected to the light receiving level display circuit 27 and the power supply plus terminals 27a, 2b of the sample and hold circuit 26.
6a and the power supply minus terminals 27b and 26b, the power of the constant voltage circuit 30 is supplied to the light receiving level display circuit 27 and the sample and hold circuit 26, and these two circuits start operating.

Each time a light receiving output is output from the output port OUT2, the light receiving output is held by the sample hold circuit 26, and is converted by the light receiving level display circuit 27 into a voltage suitable for display by the level adjusting voltmeter 7. ,
The signal is output to the voltmeter 7 for level adjustment via the plug 6.

Next, the light receiving level adjusting volume 44 is adjusted so that the level adjusting voltmeter 7 indicates a predetermined voltage value.

When the level adjustment is completed, the plug 6 is pulled out from the jack 55. Then, the connection between the terminals of the jack 55 is disconnected, and the connection between the power supply minus terminal 27b of the light reception level display circuit 27 and the minus terminal of the constant voltage circuit 30 is eliminated. The power supply to the hold circuit 26 is cut off.

As described above, when the plug 6 is pulled out of the jack 55 and the voltmeter 7 for level adjustment is removed, the light receiving level display circuit 27 and the sample hold circuit 2
By cutting off the power supply to 6, the current consumption of the light receiving level display circuit 27 and the sample and hold circuit 26 other than during the level adjustment is reduced. In this embodiment, for example, current consumption of about 200 μA is reduced. Since the operation power is not supplied to the sample hold circuit 26, the light reception output is not held.

In the case of a fire alarm system of the polling type, the light receiving unit 2 uses a polling signal sent from the fire receiver RE and a dip switch or a ROM provided in the light receiving unit 2 (not shown). It is determined whether or not the self-address signal stored in the storage device matches with the self-address signal, and if they match, a code signal such as a fire signal may be transmitted to the fire receiver RE.

In transmitting the light emission command signal from the light receiving unit 2 to the light transmitting unit 1, instead of using the dedicated signal line 5, the polarity of the power supply line 4 is inverted or a pulse code is superimposed on the power supply voltage. May be transmitted.

[0023]

As described above, the present invention is provided in the light receiving section for adjusting the level of the light receiving output corresponding to the facing distance between the light transmitting section and the light receiving section. A three-pole jack is provided in the light-receiving section, which also serves as a power switch for the light-receiving level display circuit for converting to a level and an output terminal of the light-receiving level display circuit, and a two-pole plug connected to a level adjusting instrument is provided. The power is automatically supplied to the light reception level display circuit when it is plugged in, and the power supply to the light reception level display circuit is automatically cut off when the plug is removed from the jack. Has the effect of reducing the current consumption in the light receiving level display circuit.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing an electrical connection according to an embodiment of the present invention.

FIG. 2 is a circuit diagram showing a state in which a plug is pulled out in an electric connection of a main part of the embodiment.

FIG. 3 is a circuit diagram showing an electric connection of a conventional photoelectric separation type smoke detector.

[Explanation of symbols]

 Reference Signs List 1 light transmitting unit 2 light receiving unit 6 plug 7 voltmeter for level adjustment 27 light receiving level display circuit 27a power plus terminal 27b power minus terminal 30 constant voltage circuit 30a plus terminal 30b minus terminal 55 jack 55a positive terminal 55b positive terminal 55c negative terminal Terminal

──────────────────────────────────────────────────続 き Continuation of front page (58) Field surveyed (Int. Cl. ⁷ , DB name) G08B 17/00-17/12

Claims (1)

(57) [Claims] 1. A light-transmitting unit includes a light-transmitting unit and a light-receiving unit that are installed separately from each other and opposes each other. Is a light-receiving element for receiving light from the light-emitting element, a level adjuster for finely adjusting the level of the light-receiving output of the light-receiving element, a light-receiving amplifier circuit for amplifying the light-receiving output adjusted by the level adjuster, and an amplification circuit for the light-receiving amplifier circuit. A switch that switches the power in several stages according to the facing distance between the light-sending unit and the light-receiving unit, and compares the light-receiving output amplified by the light-receiving amplifier circuit with the fire discrimination value. A fire discrimination circuit that outputs a fire signal to the receiver, a transmission circuit that sends the fire signal of the fire discrimination circuit to the receiver, a light reception level display circuit that converts the light reception output of the light reception amplification circuit to the drive level of the level adjustment instrument, Light reception In a photoelectric separation type smoke sensor comprising an amplification circuit, a fire determination circuit, and a constant voltage circuit for supplying drive power to a light reception level display circuit, a two-pole type smoke detector connected to a level adjustment instrument at the light reception unit. A three-pole jack into which a plug is inserted is provided, one terminal of the positive terminal of the jack is connected to the output terminal of the light receiving level display circuit, and the other terminal of the positive terminal of the jack is connected to the light receiving level display circuit. A negative terminal of the jack is connected to a negative terminal of the constant voltage circuit, and a positive terminal of the constant voltage circuit is connected to a positive power terminal of the light receiving level display circuit. Photoelectric photoelectric smoke detector.