JPS5850096A - Fire detector for automatic extinguisher for kitchen fire - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides an automatic fire extinguishing system for kitchen fires that automatically extinguishes kitchen fires that often occur during cooking using oil. This invention relates to a flame detector that outputs a detection signal.

Conventionally, this type of automatic fire extinguishing system
The one shown in the figure is known. That is, a flame detector (3) consisting of a heat-sensitive element such as a thermistor is installed at a predetermined location in the 7-door duct (2) above the gas stove (1).
At the same time, the hood (2a) of the duct (2) is installed.
) is provided with a fire extinguishing nozzle (5) of an automatic fire extinguishing system (4) filled with a fire extinguishing agent, and the flame detector (3) is connected to the automatic fire extinguishing system (4). Place the pot on top (
6), etc., when the oil in the pot (6) ignites and the flame increases, causing a fire, the flame detector (3) detects the flame and sets off the automatic fire extinguishing device (4). ) is activated to inject extinguishing agent from the extinguishing nozzle (51), thereby automatically extinguishing the fire.

However, in the conventional flame detector, the flame detector is composed of a heat-sensitive element such as a thermistor with a relatively large thermal time constant, so there is a time delay in detecting the flame, even though prompt extinguishing is required. As a result, there is a problem that there is a delay in extinguishing the fire, and the duct (2
), even if there is no fire, for example, a simple gas stove (1
) is likely to cause high temperatures, and therefore, if the flame detector (3) is disposed inside the duct (2), it is likely to malfunction.

In addition, when cooking Chinese food, Fi cooks may intentionally ignite the oil in the cooking pot (6), and in such cases, it is important to distinguish the increase in flames from a fire. There was a risk of malfunction due to the inability to do so.

Therefore, the present invention has been made in view of this point, and includes a pyroelectric infrared sensor set at a certain height above the kitchen device on the side of the kitchen device and arranged at a certain height above the kitchen device. By outputting a fire signal when the flame increases to a predetermined height, it eliminates the time delay in flame detection and eliminates malfunctions caused by erroneously detecting flames from simple gas stoves, etc. It is an object of the present invention to provide a flame detector for an automatic fire extinguishing system for kitchen fires, which enables automatic extinguishing by accurate and rapid detection of fire.

Furthermore, the present invention is arranged at a predetermined height position above the kitchen equipment on the side of the kitchen equipment and set at an elevation angle of zero or more,
The pyroelectric infrared sensor outputs a fire signal when the flame increases or decreases above a predetermined height, and outputs an extinguishing signal when the flame decreases below a predetermined height. A control circuit is provided that receives a fire signal, counts a set time, and outputs an extinguishing signal when the count is completed, and clears the count upon receiving the extinguishing signal from the pyroelectric infrared sensor. A fire detector for an automatic fire extinguishing system for kitchen fires is designed to output a fire extinguishing command signal only when the fire extinguishing command signal has elapsed for a set period of time, thereby preventing malfunction due to a temporary increase in flames. This is what we intend to provide.

In addition, the present invention provides a fire extinguishing switch that generates a fire extinguishing command signal by manual operation, and when the fire is re-ignited, the fire extinguishing command signal is immediately output by operating the fire extinguishing switch. It is an object of the present invention to provide a fire detector for an automatic fire extinguishing system for kitchen fires, which is capable of reliably extinguishing fires even in the event of re-ignition.

Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings. Since the general structure of the automatic fire extinguishing system for kitchen fires has already been described with reference to FIG. 1, detailed explanation thereof will be omitted.

In FIG. 2, a +71 Fi pyroelectric infrared sensor (7) is used, for example, on a gas stove (
1) disposed at a predetermined height position above the gas stove (1) on the side wall (8) (for example, at a height of 20 cm);
In addition, an infrared transmitting window (7
a) is mounted horizontally or diagonally upward, and a condensing lens (7b) is disposed inside the tube (7b) constituting the infrared transmission window (7a). Stove (
1) When the flame increases above a predetermined height, the increase in flame is detected and a positive pulse as shown in Figure 4 (a) is generated to output a fire signal, while the flame increases to a predetermined height. When the flame has shrunk below a certain point, it detects the shrinkage of the flame and outputs a negative pulse as shown in Figure 4 +dr to output a flame extinguishing signal, and the Ryokawa power signal is input to the control circuit (9). ing.

The control circuit (9) is shown in FIG. 3, GO) is an amplifier connected to the pyroelectric infrared sensor (7), and the amplifier (10) detects a positive pulse. A first comparator (111, !: connected to a second comparator tlZ that detects a negative pulse, and the first comparator 'p'
The anke RS flip 70 is connected to the 5 terminal of the tube a3, and the second comparator a2 is connected to the RS
Flip 70 knob (connected to the terminal of 131,
When a flame signal is output from the pyroelectric infrared sensor (7), the flame signal is amplified by the amplifier u0 and then detected by the first comparator 01), and the RS flip 70 tube (1)
On the other hand, when an extinguishing signal is output from the pyroelectric infrared sensor (7), the extinguishing signal is sent to the amplifier (
After being amplified by 101, it is detected by a second comparator (12) and outputted to the R terminal of R57 lip 70 tube a3.

Furthermore, the +14) Fi timer is composed of a binary kakunta (1ω and a variable frequency oscillator α6) and a frequency variable device 0η, and the input side of the binary kakunta 0♂ has a Rs7 lip with g. The Q terminal of group 70 is connected, and the output side of the binary counter (151 is connected to the monostable multivibrator (19) through a diode, and the output side of the binary counter (151) is connected to the monostable multivibrator (19), and the output from the first comparator U1 is When the RS clip 70 knob of the flame signal is input to the S terminal of 131, the RS clip 70 knob (1) is set by the output signal output from the Q terminal of
1, the count is completed when the set time η (for example, 16 seconds) set by the variable frequency vibrator has elapsed, and the extinguishing command signal is sent to the diode u.
output to the monostable multi-pipe rake (19) via the monostable multi-vibrator 09), and operate the automatic fire extinguishing device (4) by the output signal from the monostable multi-vibrator 09).
When the R87 lip 70 knob 113) of the extinguishing signal from the comparator 02 is input to the terminal, it is reset by the output signal output from the q terminal of the EL S7 lip lip 131 to clear the count of the binary counter α9. It is composed of

In addition, ■ is a fire extinguishing switch connected to the front stage of the monostable multivibrator 01, and the fire extinguishing switch (
By manually closing B), a fire extinguishing command signal is forcibly input directly to the monostable multivibrator (1ω) without going through the timer (141).

M-) and (21) are reset switches, and by manually closing () of the reset switch,
RS flip 7 through the reset switch (2111 connected OR circuit @ and NOT circuit (to))
0 tube (131 and monostable multi-φ vibrator II
This is to reset I. Also, ■ and □□□ are threshold setting circuits that set the thresholds of the first comparator a1J and the second comparator 05, respectively.

Next, the operation of the above embodiment will be explained with reference to the flowchart shown in FIG. 6. In the first step (SL) from the start (SO), by closing the reset switch) I need to reset the multivibrator (l!!)/76
゜Then, in the second step (S2), it is determined whether a flame signal is output from the pyroelectric infrared sensor (7), that is, the pot (6) of the gas stove (1) is ignited and the flame reaches a predetermined height. If the judgment is NO, the process remains at the second step (S2), while if the judgment is YES (usually, the flame reaches a predetermined height or more 5.6 seconds after ignition). The process proceeds to the third step (S8), and the third step (S3
), the fire signal of the pyroelectric infrared sensor (7) is
As shown in Fig. 5, after being amplified by the amplifier (1), this amplified fire signal is detected by the first converter α1 and input to the S terminal of the RS clip 70 tube a31. Niyori, the RS clip front (13
) with the negative pulse output signal from the Q terminal of timer I.
is set and counting begins.

Thereafter, the process proceeds to a fourth step (S4), and in the fourth step (S4), it is determined whether a flame extinguishing signal is output from the pyroelectric infrared sensor (7), that is, whether the increase in flame is temporary. If YES, the pyroelectric infrared sensor (
After the extinguishing signal of 7) is amplified by the amplifier OI, it is detected by the second comparator α and the R57 lip 70 tube 0J is detected.
By being input to the terminal, the RS flip 70
The timer αa is reset by the positive pulse output signal from the q terminal of the knob (131), and the second step (S2
).

On the other hand, in the case of No, in which the pyroelectric infrared sensor (RI) does not output a flame extinguishing signal, the process proceeds to the sixth step (S6), and after the flame signal is output in the sixth step (S6), Determine whether the set time (1) (for example, 16 seconds) has elapsed, and if NO, proceed to the fourth step (S4).
On the other hand, in the case of YES, it is determined that a fire has occurred in the seventh step (S7), and the fire extinguishing command signal is sent from the timer (141) to the monostable multivibrator (19) as shown in FIG. The output signal from the monostable multivibrator α is outputted to the automatic fire extinguishing device (4), so that extinguishing is automatically performed in the eighth step (S8) and the process ends.

After that, if a fire ignites again on the gas stove (1), by manually operating the fire extinguishing switch, the fire extinguishing command signal will be immediately input to the monostable multivibrator u0, and the timer (set by God) will be activated. The automatic fire extinguishing device (4) will immediately extinguish the fire automatically without elapse of time LI).

Here, since the flame detector is configured using a pyroelectric infrared sensor (7), there is no time delay in detecting the occurrence of a fire, and the fire can be extinguished automatically. I can do it. Further, a focused infrared sensor (7) is disposed on the side of the gas stove (1) at a predetermined height above the gas stove (1), and its infrared transmission window (
7a) is oriented horizontally or diagonally upward, the pyroelectric infrared sensor (7) will not detect the flame of the gas stove (1) and malfunction. Moreover, compared to the conventional one installed inside the duct (2), the increase in flame can be detected with high accuracy without being affected by other factors, and malfunctions can be prevented more reliably. .

Furthermore, when the flame increases temporarily during cooking, since the flame increases within a predetermined time, the timer (!a) is reset by the extinguishing signal of the pyroelectric infrared sensor (7). , an extinguishing command signal is not output, and malfunctions due to a temporary increase in flame can be prevented.In addition, it is determined whether the flame exceeding a predetermined height is temporary or not depending on the set time ( Depending on the sword, this set time (I) can be arbitrarily set using the variable frequency oscillator αe and the variable frequency generator (1η. Therefore, the cook can set the set time (1) as appropriate according to his/her own cooking. In this case, if the frequency is increased by the frequency variable device, the frequency variable oscillation@(1e setting time I1
1 becomes shorter.

In addition, if a re-ignition occurs after automatic extinguishing, when the extinguishing switch is closed, a fire-extinguishing command signal is generated immediately, and the re-ignition is immediately stopped without waiting for the set time to elapse. Since the fire is extinguished, it is possible to ensure that the fire is extinguished.

When the temperature of the flame decreases due to the start of extinguishing by the automatic fire extinguisher (4), the pyroelectric infrared sensor (7) may output a flame extinguishing signal even though extinguishing has not been completed.

In this case, the timer will be reset by the extinguishing signal, but the monostable multivibrator 09
), the fire extinguishing command signal is converted into a signal with a wide rising and flat part, so the automatic fire extinguishing system (4) will not be stopped by mistake.

Further, the flame signal and extinguishing signal of the pyroelectric infrared sensor (7) are specifically amplified by an amplifier tll shown in FIG. At that time, make sure that the bounce of the flame signal is not confused with the flame signal and reset the timer αa, and that the bounce of the flame signal is not confused with the flame signal and the timer αa is not reset.
114) is never set.
It is preferable to appropriately set the coupling capacitance, etc. of 1, or to connect directly, so that the respective rebound portions are made sufficiently small.

Therefore, according to the first aspect of the present invention, since a fire signal is output when the flame increases to a predetermined height or more, it is possible to improve the immediate performance of automatic extinguishing and to prevent malfunctions. This is something that can be prevented.

Further, according to the second aspect of the present invention, since the extinguishing command signal is output only when the flame of a predetermined height or more continues for a set time, it is possible to further prevent malfunctions. It is.

Further, according to the third aspect of the present invention, when the fire is re-ignited, the fire extinguishing command signal is immediately output by operating the fire extinguishing switch, so that it is possible to ensure that the fire is extinguished.

[Brief explanation of the drawing]

Fig. 1 is an overall schematic diagram of the conventional automatic fire extinguishing system for kitchen fires, Figs. 2 to 6 show embodiments of the present invention, and Fig. 2 shows how the pyroelectric infrared sensor is installed. Figure shown, 3rd
The figure shows the electrical circuit diagram of the control circuit, Figure 4 (a) and tC4
The output waveform diagram of the pyroelectric infrared sensor, Figures 5 (a) and 101 are output waveform diagrams of each part of the control circuit, Figure 6 is a flowchart diagram, and Figure 7 is an electrical diagram showing the specific circuit of the amplifier. It is a circuit diagram. 7... Pyroelectric infrared sensor, 9... Control circuit, 20...
...Fire extinguishing switch. No. 70 Aircraft 6

Claims (3)

[Claims] (1) A pyroelectric infrared sensor (7) is installed on the side of the kitchen device (1) at a predetermined height above the kitchen device (1) with an elevation angle of zero or more, so that the flame is An automatic fire extinguishing device for kitchen fires, which is characterized by outputting a fire signal when the flame exceeds a height. (2) It is installed on the side of the kitchen device (1) at a predetermined height above the kitchen device (1) with an elevation angle of zero or more, and sends a fire signal when the flame increases to a predetermined height or higher. a pyroelectric infrared sensor (7) that outputs an extinguishing signal when the flame shrinks below a predetermined height;
7) After receiving the fire signal, count the set time (1),
A control circuit 03 outputs an extinguishing command signal when the count is completed, and also clears the count upon receiving the extinguishing signal from the pyroelectric infrared sensor (7), and when the flame exceeds a predetermined height continues for a set time. A flame detector for an automatic fire extinguishing system for kitchen fires, characterized in that it outputs a fire extinguishing command signal only when there is a fire. (3) disposed at a predetermined height position above the kitchen device (1) on the side of the kitchen device (1) and set at an elevation angle of zero or more;
a pyroelectric infrared sensor (7) that outputs a fire signal when the flame increases above a predetermined height, and outputs a flame extinguishing signal when the flame shrinks below a predetermined height; Upon receiving the fire signal from the external sensor (7), it counts the set time (η) and outputs a fire extinguishing command signal when the count is completed, while clearing the count upon receiving the flame extinguishing signal from the pyroelectric infrared sensor (7). It is equipped with a control circuit a, 1, which outputs a fire extinguishing command signal only when the flame continues to exceed a predetermined height, and a fire extinguishing switch (2) which generates a fire extinguishing command signal by manual operation. A flame detector for an automatic fire extinguishing system for kitchen fires, characterized in that a fire extinguishing command signal is immediately output by operating the fire extinguishing switch (4).