JPH0222779Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field] The present invention relates to a gas leak receiver that receives a signal from a gas leak sensor and generates a gas leak sound.

[Background technology]

FIG. 1 is a circuit diagram showing the configuration of a conventional gas leak receiver. The receiver shown in the figure sounds a trouble sound when the power to the detector is turned off, and a gas leak sound when there is a gas leak, but the gas leak sound does not sound until a certain period of time has passed after receiving the gas leak sound. ing. In FIG. 1, T ₁ and T ₂ are input terminals for trouble signals, and G ₁ and G ₂ are input terminals for gas leak detection signals. Trouble signal is L
When it rises from level to H level, the diode
Transistor Q ₁ is turned on via D ₁ and D ₂ .
Furthermore, at the moment when the trouble signal rises, a trigger is applied to thyristor Q ₂ via capacitors C ₁ and C ₂ , turning on thyristor Q ₂ and maintaining its conduction thereafter. As a result, the trouble sound generation circuit 1 operates and trouble sound is generated. To stop the trouble sound, a normally closed sound stop switch S is turned off. The sound stop switch S is provided with an interlocking switch _S11 and a switch _S12 , the switch _S11 is used to stop trouble sounds, and the switch _S12 is used to prevent gas leak sounds. The purpose of combining the sound stop switches S into one in this manner is to save space and to prevent erroneous operation, which would easily occur if two were provided. When the gas leak detection signal rises from L level to H level, the diode
Transistor Q ₃ is turned on via D ₃ and D ₄ .
Also, at the moment the gas leak detection signal rises,
A trigger is applied to thyristor _Q4 via capacitors _C3 and _C4 , and thyristor _Q4 turns on.
From then on, the continuity is maintained. As a result, the anode potential of thyristor Q ₄ decreases, and the input voltage applied to the negative input terminal of comparator Q ₅ increases across the resistors R ₁ and R ₂ applied to the positive input terminal of comparator Q ₅ . lower than the divided voltage,
The output of comparator _Q5 rises from L level to H level. Therefore, transistor _Q5 is
It turns on immediately after a gas leak signal is input. On the other hand, a timer circuit 2 is provided at the base input of the transistor _Q7 , and the output of this timer circuit 2 becomes H level after a certain period of time has passed after the gas leak detection signal rises. Transistor _Q7 turns on and buzzer 3 sounds.
If the gas leak detection signal returns to L level before the output of timer circuit 2 becomes H level, the transistor
Q ₇ is not turned on and buzzer 3 does not sound. When the gas leak detection signal continues for a certain period of time and the buzzer 3 sounds, to stop the buzzer 3 from sounding, turn off the sound stop switch S and press the switch.
This is what opens S ₁₂ .

By the way, in such a conventional gas leak receiver, gas leak detection signals and trouble signals are received from a large number of gas leak sensors, so a gas leak sensor on a certain line outputs a gas leak detection signal and the timer circuit 2 is activated. If a trouble signal is received from a gas leak sensor on another line before a certain period of time has elapsed, a trouble sound will sound, and if you operate the sound stop switch S at that point, the trouble sound will stop and the sound will stop after the above certain period of time. The gas leak sound that was supposed to be generated was also reset, and there was a risk that the gas leak would be overlooked.

[Purpose of invention]

The present invention was developed in view of the above points, and its purpose is to prevent the gas leak detection signal from being missed even if a switch is operated to stop the trouble sound. There is a gas leak receiver to provide.

[Disclosure of invention]

The configuration of _the present invention will be described below with reference to the illustrated embodiment. As shown in _FIG . , a timer circuit 2 that produces an output after a certain period of time, and a timer circuit 2 that is set to be able to sound when a gas leak detection signal is input, and is enabled to sound when the gas leak detection signal disappears or the first normally closed switch _S12 is opened. a first sound generating means 4 whose state is reset and which starts a ringing operation based on the output of the timer circuit 2 and generates a gas leak sound; and one of the plurality of gas leak detectors X ₁ and X ₂ . 1
The sounding operation starts when there is a trouble signal from the first switch, and while there is a trouble signal, the second normally closed switch is activated.
A second sound generating means 5 that continuously generates a trouble sound until the circuit of S ₁₁ is opened, and a normally closed type switch that is connected in parallel to the first normally closed type switch and is opened by the output of the timer circuit 2. It has a switch means 6. In the embodiment shown in FIG. 2, the normally closed contact of the relay Ry is used as the normally closed switch means 6, and when the output of the timer circuit 2 becomes H level, the transistor _Q7 is turned on and the relay is switched on. Ry
is also turned on, and the switch means 6 is started. For details on the structure of other parts, please refer to Part 1.
Since this is the same as in the conventional example shown in the figure, parts having the same functions are given the same reference numerals and their explanations will be omitted. _{Each gas} leak _{detector X 1 ,}
The wiring is such that X ₁ ′ and X ₂ ′ are connected to terminals X ₁ and X ₂ , respectively. Therefore, in this embodiment, a gas leak detector (for example, X ₁ ) of a certain line
outputs a gas leak detection signal, timer circuit 2 starts time-limited operation, and the output of timer circuit 2 becomes H.
A trouble signal is received from a gas leak detector (for example _, X ₂ ) on another line before the level is reached, and a trouble sound is sounded _. Even if the circuit is opened, since the switch means 6 is closed, the thyristor _Q4 in the first sound generating means 5 will not be reset, so there is no possibility of missing the gas leak detection signal as in the conventional case. . However, in this embodiment, switch S ₁₁
Switch S ₁₁ and Switch S 12 are configured to work together, but even if Switch S ₁₁ and Switch S ₁₂ do not work together, it will not be possible to use the system when the trouble sound sounds, as if you pressed the wrong switch. In the case, the first sound generating means 5 for gas leakage sound generation
Since the thyristor _Q4 is never reset, there is no possibility of missing the gas leak detection signal.

[Effect of idea]

The present invention is constructed as described above, and includes a normally closed switch in parallel with a first normally closed switch that resets the ringable state of the first sound generating means for generating gas leak sound when the circuit is opened. Since the switch means is connected and the normally closed switch means is opened by the output of the timer circuit, the first normally closed type switch means is connected to reset the first sound generating means for generating trouble sound when a trouble occurs. Even if the closed type switch is opened in conjunction with the second normally closed type switch or due to malfunction, the sounding state of the first sound generating means will not be reset, and the gas leak detection signal will not be detected. It has the advantage that there is no danger.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram of a conventional example, and FIG. 2 is a circuit diagram of an embodiment of the present invention. X ₁ and X ₂ are gas leak detectors, 2 is a timer circuit,
4 and 5 are sound generating means, 6 is a switch means, S ₁₁ ,
S ₁₂ is a switch.

Claims (1)

[Scope of utility model registration request] There is a timer circuit that starts operating in response to a gas leak detection signal from any one of the multiple gas leak detectors and generates an output after a certain period of time, and a timer circuit that is set to be able to sound when a gas leak detection signal is input, The sounding enabled state is reset by disappearance of the leakage detection signal or opening of the first normally closed switch,
The ringing operation is started by the output of the timer circuit, and the ringing operation is started by a trouble signal from any one of the first sound generating means that generates a gas leak sound and the plurality of gas leak detectors. However, while there is a trouble signal, a second sound generating means that continuously generates a trouble sound until the second normally closed switch is opened is connected in parallel to the first normally closed switch. and a normally closed switch means which opens at the output of a timer circuit.