JPS58203319A - Safety device for oxygen starvation in burner - Google Patents

Abstract

PURPOSE:To sound an alarm through the detection of the decrease in an oxygen concentration and the increase in a carbon monoxide concentration, by a method wherein, in a burner such as kerosene heaters, an oxygen starvation sensor, detecting an oxygen starvation condition, is employed. CONSTITUTION:With a button 8 for ignition depressed, a point (d) is positioned to a level higher than that of a point (e), and an operational amplifier 35 has a high output point (f). Thus, a circuit of an oxygen starvation sensor 14 connected to a point (f) actuates. If an oxygen concentration is 20% or more, a resistance value is high, and thereby an operational amplifier 38 has a low output point (h). Thus, a luminous diode 45 is prevented from lighting, a buzzer 28 is also kept from alarming. If, however, an oxygen concentration decreases, the oxygen starvation sensor 14 is reduced in a resistance value, and the operational amplifier 38 has a high output point (h), whereby a transistor 44 works, and the luminous diode 45 lights ON to sound an alarm. Form that time, a capacitor 43 starts to be charged, and a potential at a point (j) begins to rise gradually. When exceeding a potential at a point (e) for about one minute, a transistor 52 operates to sound the buzzer 28 and to issue other alarms.

Description

[Detailed Description of the Invention] The present invention uses a combustor such as a kerosene stove to detect a decrease in the oxygen concentration in the usage environment due to combustion and an increase in the carbon oxide concentration, so as not to have an adverse effect on the human body. The purpose is to

Figure 1 shows a conventional kerosene stove on page 2. Inside the outer device there is a reflector 2, in the center of the curved surface there is a combustion tube 3, and inside it there is a capillary tube for the wick. By burning the kerosene that has been sucked up to the top due to the phenomenon, the combustion tube 3 is made red hot, and the heat is radiated to the front of the dystope by the reflection plate 2. Nao Mami 4
The wick is moved up and down, and when it is raised, a button 5 is pressed to ignite the wick and start combustion. Further, when the other knob 26 is pushed downward, the lock of the knob 4 is released, and as the knob 4 returns to its original position, the lamp wick inside the combustion tube 3 also lowers to extinguish the fire.

A kerosene heater with such a structure consumes oxygen in the environment in which it is used, and if there is less oxygen supplied from the outside, the oxygen concentration will decrease, and as a result, carbon monoxide produced by combustion will increase. In such a case, it is necessary to sufficiently ventilate the room because it has a negative effect on the human body, and the user consciously opens the window at regular intervals to let in fresh air. However, if this ventilation is neglected, the oxygen concentration will decrease and carbon oxide will increase, which is extremely dangerous.

The present invention eliminates such conventional drawbacks, and one embodiment of the present invention will be described below with reference to the accompanying drawings.

Figures 2, 3, 4, and 6 show one embodiment of the present invention. Figure 2 is an internal structural diagram, Figure 3 is a front view, and Figure 4 is an oxygen-deficient The characteristic diagram of the sensor, and FIG. 6 is a control circuit diagram.

First, in FIG. 2, a semicircularly curved reflector plate 2 is provided inside a box-shaped outer device, and a cylindrical combustion cylinder 3 is provided in the center thereof. The combustion cylinder 3 is rotated by the rotation knob 4.
A cylindrical lamp wick 6 moves up and down inside the lamp. When the ignition knob 5 is pressed when the wick 6 rises, the switch 8 closes and the ignition heater 9 generates heat with the voltage supplied from the dry battery power source (an AC power source is also acceptable) 7. is brought close to the lamp wick 6. At this time, the wick 6 is sucking up the kerosene stored in the fuel tank 1o by capillary action, so the ignition heater 9
It is ignited by. Inside the combustion tube 3, there are a cylindrical inner flame tube 12 and an outer flame tube 13, and air for combustion is supplied between the inner and outer flame tubes 12 and 13 by a draft (arrow A).

In the bottom pull type kerosene stove with such a configuration, the oxygen deficiency sensor 14 is installed in the case 15 above the approximate center of the combustion tube 3, and its lead wire 16 is connected to the control circuit through a place where the temperature is not very high. Reach 17. A voltage is supplied to the control circuit 17 from the dry battery power source 7 through another lead wire 18 . On the other hand, rotate the rotary knob 4, and
Rotate knob 4 in conjunction with the movement of pushing upwards.
A cam 19 is coaxially located with the rotary knob 4 and operates the microswitch 2o in conjunction with the operation of the rotary knob 4.

This microswitch 2o supplies the voltage of the dry battery power source 7 to the entire control circuit 17. The switch 8 operated by the ignition knob 5 supplies voltage to the ignition heater 9 through the ignition operation, operates a self-holding circuit in the control circuit 17, and operates the oxygen deficiency sensor circuit. In this way, unless the ignition operation is performed, the voltage is not supplied to the control circuit 17.
The reason why the base supply is not performed frequently is to suppress the consumption of the dry battery power source 17 as much as possible.

Fig. 3 is a front view of Fig. 2, and includes parts that cannot be fully explained in Fig. 2, especially the seismic automatic fire extinguishing system (hereinafter referred to as ``Fukui'').

) is shown. That is, the rotary knob 4 has a coaxial gear 23 of a ratchet mechanism, and this gear 2
3 is locked to a lever 24 for damping vibrations. When the push button 25 is pushed downward, the weight 26 falls down and is released. When the lock is released, the rotation knob 4 returns to its original position and the wick 6 also descends due to the biasing force of the spring. , designed to extinguish the fire.

Of course, if the weight 26 swings due to an earthquake or the like, the lock will be released due to the strength of the earthquake, and a similar fire extinguishing operation will be performed.

Figure 4 shows the characteristics of the oxygen deficiency sensor 14. The horizontal axis shows the oxygen concentration in the combustion atmosphere, and the vertical axis shows the resistance value of the oxygen deficiency sensor 14. As the oxygen concentration decreases, the resistance value decreases. I know it will happen.

FIG. 5 shows the control circuit 17. Dry electricity 61゛-
The battery power supply 7 is connected to the positive power supply point a of the control circuit through a microswitch (normally open switch) 20 operated by the rotary knob 4. The - side is directly connected to the - side power supply point. Ignition switch 8-a' is located between points a and b.
Ignition heater 9 through point, same < a/resistance 29 from point
A series circuit of the -0 point and the resistor 30 and a series circuit of the diode 27 and the resistor 31 and the point d and the resistor 32 are also connected.

In addition, a series circuit of resistor 33 - 0 point - resistor 34 is connected between points a and b, and an operational amplifier (hereinafter referred to as an operational amplifier) 35 is connected, with point a as a positive power source and point b as a negative power source. The points d and e are connected to the positive and negative inputs, and the resistor 36 is connected to the output points f and d of the operational amplifier 35. A series circuit consisting of nine points of the oxygen deficiency sensor 14 and a resistor 37 is connected between points f and b. Next, the q and 0 points are connected to the positive and negative inputs of the second operational amplifier 38, and a resistor 39 is connected between the output point and the q point.

Between points h and b, resistor 40 - point i - resistor 41, resistor 42
- 5 points - Connect the series circuit of capacitor 43. The base of the transistor 44 is connected to point i, the emitter to point b, and a series circuit of a light emitting diode 45 and a resistor 46 used as the first alarm means is connected between the collector and point a. The positive and negative inputs of the third operational amplifier 47 are j and e.
A series circuit consisting of a resistor 48 and a diode 49 (cathode on the j side) is connected to the output from the point k.
A series circuit of resistors 50-1 points and 61 points is connected between points b. Note that a buzzer 28 used as a second alarm means and a transistor 52 having a base at one point are connected in series between points a and b. A series circuit of resistor 53-m point-electrolytic capacitor 54 is connected between points k and b, and a resistor 5 is connected between points m and b.
6 and a normally closed push button switch 56 are connected in series.

Points m and e are connected to the positive and negative inputs of the fourth operational amplifier 57, and resistors 58 and n are connected to the output points n and m.

A series circuit of resistor 59-0 point and resistor 60 is connected between points b. Based on point 0: Connect Nidoranji Staro 10 base to point b and collector to point 1. The base, collector, and emitter of the transistor 62 are c and m.
, connect to point b.

Next, the operation will be explained.

First, in FIG. 2, turn the rotary knob 4 to raise the lamp wick 6 upward. (Figure 2 shows the state where it is already raised.

) At this time, the cam 19 simultaneously activates the micro switch 2o.
is closed. In this state, the ignition button 5 is pressed to bring the ignition heater 9 close to the lamp wick 6, and the microswitch 8 is pressed to pass the voltage of the dry battery power source 7 to the ignition heater 9 to ignite it. When you release your hand after ignition, the ignition button 6 returns to its original position. In this way, the kerosene vaporized from the wick 6 is normally combusted between the inner flame tube 12 and the outer flame tube 13. Most of the burned heat is reflected by the reflecting plate 2, and the reflected heat is transmitted to the front surface. In addition, the increased heat reaches the case 16 where the oxygen deficiency sensor 14 is located and accumulates heat inside the case 15.At the same time, oxygen, carbon oxide, etc. in the air contained in the combustion flame are also sent into the case 15. Therefore, oxygen deficiency sensor 1
4 constantly monitors the combustion state at 1 and sends the signal to the control circuit 17.

If the amount of oxygen in the air decreases, for example, by 18%, then the amount of carbon oxide increases and the resistance value of the oxygen deficiency sensor 14 decreases, and this signal causes the control circuit 1 to
7 works. To explain this with reference to FIG. 5, when the ignition button 8 is pressed, point d is higher than point e through diode I, and the output point 1 of the operational amplifier 35 becomes high. Therefore f
The circuit of the oxygen deficiency sensor 14 connected to the point operates. Fourth
As shown in the figure, when the oxygen concentration is 20% or more, the resistance value is large, so the output point of the operational amplifier 38 is low. Therefore, unless the light emitting diode 45 is lit, the buzzer 28 will not sound either.

However, when the oxygen concentration decreases, the resistance value of the oxygen deficiency sensor 14 becomes small, for example, if it is 18%, then about 1.2
When it becomes Ω, the output point of the operational amplifier 38 becomes high.
Therefore, the transistor 44 operates, the light emitting diode 46 lights up, and an alarm is issued. From that point on, charging of the capacitor 43 begins, and the potential at point j begins to gradually rise. When the potential at point e is exceeded by about 1 minute root, the transistor 52 is activated, the buzzer 28 starts sounding, and other alarms are activated.
0be is fired once. The reason why the delay of one minute is provided is because the output of the oxygen deficiency sensor 14 actually fluctuates and is not linear as shown in Fig. 4, so the buzzer 28 is not activated until the entire characteristic changes. The purpose is to make it ring. In reality, if the combustion rate decreases not only due to lack of oxygen but also due to lack of oil or adhesion of tar, a state similar to oxygen deficiency occurs, and the light emitting diode 45 lights up and the buzzer 28 sounds, which may be noisy and you want to stop it. Become. Therefore, the positive input of the fourth operational amplifier 57 is (a) connected to the capacitor 64 when voltage is applied, (b) the transistor 62 is activated by pressing the button 8, and (c) the resistance value of the oxygen deficiency sensor 14 is large. Since the output of both operational amplifiers 38 and 47 is low,
Since the point m is at a low level, the output point n of the operational amplifier 67 is at a low level, so the transistor θ is not operating. Now, the buzzer 28 is noisy, so if you press the button 56, the potential at point m becomes high, the output at point n becomes high, and the resistors 53, 66.6
8, the potential at point m is set higher than point e, so the output at point n is self-maintained at a high level. Therefore, transition 11
・Nistaro 1 operates and lowers the potential of one point, transistor 5
2 is opened and the buzzer 28 stops operating.

If you turn off the power, stop the operation, and then relight it, the self-holding function described above will be canceled, and the buzzer 28 will sound if there is a breakage or abnormality. In addition, after the buzzer 28 is turned off, if the oxygen deficiency state is recovered by opening a window and the resistance value of the oxygen deficiency sensor 14 becomes large, or if the resistance value of the oxygen deficiency sensor 14 increases, or if oil is supplied again, the oxygen deficiency sensor 14 When the value returns to the original value, the operation is as in the state (c) described above, and the m point becomes low, the operational amplifier 57 makes the output n point low, the transistor 61 becomes open, and the above-mentioned lock is released. The transistor 52 then returns to the standby state.

Furthermore, even if the buzzer is stopped by pressing the push button 56 as in (b) above, the lock will be released in the same way when the ignition button 8 is pressed. - Now, this is very important: if you have to configure it so that it will work unconsciously the next time you use it, even if it turns off once, you won't be able to use it with confidence.

Note that the self-holding circuit using the operational amplifier 36 is not directly related to the present invention, but in practice, by combining these,
A more effective circuit configuration can be obtained.

As described above, according to the present invention, even if the second alarm means is manually stopped, this stop signal is automatically restored, so that it will function normally when the next oxygen shortage occurs, resulting in extremely high safety. The value will be high.

[Brief explanation of drawings]

A front view, FIG. 4 is a characteristic diagram, and FIG. 5 is an electric circuit diagram. 14... Oxygen deficiency sensor, 17... Control circuit, 28... Buzzer (second alarm means), 45
...... Light emitting diode (first alarm means), 66
・River...Switch. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
@ Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] An oxygen deficiency sensor that detects an oxygen deficiency state, a first alarm means such as a lamp that issues an alarm when a change in the detection output of this oxygen deficiency sensor exceeds a certain value, and a second alarm means that is operated manually. An oxygen deficiency safety device for a combustor, comprising a memory circuit capable of stopping the oxygen deficiency sensor, and configured to release the memory when the detection output of the oxygen deficiency sensor returns to a certain value or less.