JPS6365846B2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention uses a combustor such as a kerosene stove, in particular, to detect a decrease in the concentration of enzymes in the usage environment due to combustion, or an increase in the concentration of carbon monoxide, so as to prevent any adverse effects on the human body. The purpose is to

Figure 1 shows a conventional kerosene stove. Inside the exterior 1 there is a reflector 2, and in the center of the curved surface there is a combustion tube 3. By burning the kerosene sucked up to the top, the combustion tube 3 is made red hot, and the heat is radiated to the front of the stove by the reflection plate 2. The wick of the knob 4 is moved up and down, and when raised upwards, the button 5 is pressed to ignite the wick and start combustion. Also, if you press the other knob 25 downward, knob 4
When the lock is released and the knob 4 is returned to its original position, the wick inside the combustion tube 3 also goes down and extinguishes the fire.

A kerosene heater with such a structure consumes oxygen in the environment in which it is used, and if the supply of oxygen from the outside is low, the oxygen concentration gradually decreases, and as a result, the amount of carbon monoxide produced by combustion increases. In such cases, 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, oxygen concentration will decrease and carbon monoxide 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 5 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 A characteristic diagram of the sensor, and FIG. 5 is a control circuit diagram.

First, in FIG. 2, a semicircularly curved reflector plate 2 is provided inside a box-shaped exterior 1, and a cylindrical combustion tube 3 is provided in the center thereof. Further, a cylindrical lamp wick 6 is moved up and down inside the combustion tube 3 by means of a rotary knob 4. 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 cell power supply (alternating current power supply is also acceptable) 7. The lamp wick 6 is brought close to it. At this time, the wick 6 is sucking up the kerosene stored in the fuel tank 10 by capillary action, so it is ignited by the ignition heater 9. Inside the combustion tube 3, there are a cylindrical inner flame tube 12 and an outer flame tube 13, which transport air for combustion into the inner flame tube and the outer flame tube 1.
It is supplied by draft (arrow A) between 2 and 13.

In a portable 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 so that the rotary knob 4 is interlocked with the operation of pushing the lamp wick 6 upward.
There is a cam 19 coaxially with the rotary knob 4, and the micro switch 20 is operated in conjunction with the operation of the rotary knob 4. This microswitch 20 supplies the voltage of the dry battery power source 7 to the entire control circuit 17. In addition, the switch 8 is controlled by the ignition knob 5.
By the ignition operation, voltage is supplied to the ignition heater 9, and the self-holding circuit in the control circuit 17 is operated, thereby operating the oxygen deficiency sensor circuit. The reason why voltage is not supplied to the control circuit 17 unless the ignition operation is performed 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 particularly shows the parts that cannot be fully explained in FIG. That is, the rotary knob 4 coaxially has a gear 23 for a ratchet mechanism, and this gear 23 is engaged with a lever 24 for damping vibrations. This locking is done by push button 2.
When the weight 5 is pushed downward, the weight 26 falls down and is released. When the lock is released, the rotary knob 4 returns to its original position and the wick 6 is also lowered by the biasing force of the spring, extinguishing the fire. There is.

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.
FIG. 4 shows the characteristics of the oxygen deficiency sensor 14.
The horizontal axis shows the oxygen concentration of the combustion atmosphere, and the vertical axis shows the resistance value of the oxygen deficiency sensor 14, and it can be seen that as the oxygen concentration decreases, the resistance value also decreases.

FIG. 5 shows the control circuit 17. The dry battery power source 7 is connected to the + side power source point a of the control circuit through a micro switch (normally open switch) 20 operated by the rotary knob 4. One side is directly connected to one side power supply point b. Between points a and b, there is an ignition switch 8, an ignition heater 9 through point a', and a series circuit of resistor 29, resistor 30, resistor 29, resistor 31, and diode 27, resistor 31, and d from point a'.
A series circuit of resistor 32 is also connected.

Also, between points a and b, there is a resistance 33 - point e - resistance 3
An operational amplifier (hereinafter referred to as an operational amplifier) in which 4 series circuits are connected, and the positive power source is at point a, and the negative power source is at point b.
The points d and e are connected to the positive and negative inputs of the operational amplifier 35, and the resistor 36 is connected to the output points f and d of the operational amplifier 35. Between points f and b, there is an oxygen deficiency sensor 14 - point g.
A series circuit of resistor 37 is connected. Next, connect points g and e to the positive and negative inputs of the second operational amplifier 38,
A resistor 39 is connected between the output points h and g.
A series circuit of resistor 40-point i to resistor 41 and resistor 42-point j to capacitor 43 is connected between points h and b. The base of the transistor 44 is connected to a point i, the emitter is connected to a point b, and a series circuit of a light emitting diode 45 and a resistor 46 used as a first alarm means is connected between the collector and a point a. The positive and negative inputs of the third operational amplifier 47 are connected from points j and e, and a series circuit of a resistor 48 and a diode 49 (the cathode is on the j side) is connected to the outputs k and j, and between the kb points. Connect a series circuit between resistor points 50-1 and 51. Note that a buser 28 used as a second alarm means and a transistor 52 having a base at point l are connected in series between points a and b. Resistance 53 between points k and b - point m
A series circuit of an electrolytic capacitor 54 is connected between points m and b, and a series circuit of a resistor 55 and a normally closed push button switch 56 is connected between points m and b.

The positive and negative inputs of the fourth operational amplifier 57 are m and e.
Connect the points, and connect the outputs to the n and m points with a resistor 58,
A series circuit of resistor 59-point o-resistor 60 is connected between points n and b. The base of the transistor 61 whose base is at point o is connected to point b, and the collector is connected to point l. Further, the base, collector, and emitter of the transistor 62 are connected to points c, m, and b.

Next, the operation will be explained.

First, in FIG. 2, turn the rotary knob 4 to raise the lamp wick 6 upward. (FIG. 2 shows the state in which it has already been raised.) At the same time, the micro switch 20 is closed by the cam 19. In this state, the ignition button 5 is pressed to bring the ignition heater 9 close to the lamp wick 6, and the micro switch 8 is pressed to apply the voltage of the dry battery power source 7 to the ignition heater 9 to ignite the lamp. When you release your hand after ignition, the ignition button 5 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. Further, the increased heat reaches inside the case 15 where the oxygen deficiency sensor 14 is located, and accumulates heat inside the case 15.

At the same time, oxygen, carbon monoxide, etc. in the air contained in the combustion flame are also sent into the case 15, so the oxygen deficiency sensor 14 constantly monitors the combustion state and sends a signal to the control circuit 17.

If the amount of oxygen in the air decreases to, for example, 18%, carbon monoxide increases and the resistance value of the oxygen deficiency sensor 14 decreases, and the control circuit 17 operates based on the signal. To explain this using FIG. 5, when the ignition button 8 is pressed, the diode 27
The point d becomes higher than the point e through the operational amplifier 35.
The output at point f becomes high. Therefore, the circuit of the oxygen deficiency sensor 14 connected to point f operates. From FIG. 4, when the oxygen concentration is 20% or more, the resistance value is large, so the output point h of the operational amplifier 38 is low. Therefore, if the light emitting diode 45 is not lit, the buzzer 28 will not sound either.

However, as the oxygen concentration decreases, the resistance value of the oxygen deficiency sensor 14 decreases, for example, to 18%, and when it becomes approximately 1.2KΩ, the output h point of the operational amplifier 38 becomes high, and therefore the transistor 44 does not operate. The light emitting diode 45 lights up and issues an alarm. From that point on, charging of the capacitor 43 begins, and the potential at point j begins to gradually rise. When the potential at the point e is exceeded in about one minute, the operational amplifier 47 operates to change the output point k from low to high, operating the transistor 52 and making the buzzer 28 sound. At the same time, the + input point j of the operational amplifier 47 is connected to the diode 4.
9 and resistor 48, even if the input state changes thereafter, the operation of the operational amplifier 47 will be locked (memorized) with the output k point kept high. 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, since the positive input of the fourth operational amplifier 57 is connected to (a) the capacitor 54 when voltage is applied,
(b) Since the transistor 62 is activated by pressing the button 8, (c) Since the resistance value of the oxygen deficiency sensor 14 is large and the outputs of the operational amplifiers 38 and 47 are low, m
Since the point is at a low level, the output point n of the operational amplifier 57 is at a low level, so the transistor 61 is not operating. Now, the buzzer 28 is noisy, so the button 56
When you press , the potential at point m becomes high and the output at point n becomes high.Since the potential at point m is set higher than point e due to the relationship between resistors 53, 55, and 58, the output at point n becomes high. Self-maintained. Therefore, transistor 61 operates to lower the potential at point l, transistor 52 is opened, and buzzer 28 stops operating.

After turning off the power and stopping operation,
When it is re-ignited, the self-holding is released, and the buzzer 28 will sound if there is an abnormality. In addition, after the buzzer 28 is stopped, the oxygen deficiency condition is recovered by, for example, opening a window, and the oxygen deficiency sensor 1
Oxygen deficiency sensor 14 can be activated by resupplying oil when the resistance value of sensor 4 becomes large or due to oil shortage.
When the value returns to its original value, the operation occurs in the state (c) described above, and the point m becomes low, the operational amplifier 57 makes the output point n low, the transistor 61 becomes open, and the lock is released. The transistor 52 then returns to the standby state.

Further, even if the buzzer is stopped by pressing the push button 56 as in (b) above, pressing the ignition button 8 will similarly release the lock.

In other words, alarms such as the buzzer 28 are extremely important as safety devices, and cannot be used with confidence unless they are configured so that they will operate unconsciously the next time they are used even if they are turned off once. be.

Although the self-holding circuit using the operational amplifier 35 is not directly related to the present invention, a more effective circuit configuration can be obtained by combining them in practice.

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]

FIG. 1 is a perspective view showing a conventional example, FIG. 2 is a partially cutaway side view of a combustor according to an embodiment of the present invention, FIG. 3 is a front view of the same, FIG. 4 is a characteristic diagram of the same, and FIG. The figure is the same electrical circuit diagram. 14...Oxygen deficiency sensor, 17...Control circuit, 28
... Buzzer (second alarm means), 45 ... Light emitting diode (first alarm means), 56 ... Switch.

Claims (1)

[Claims] 1. An oxygen deficiency sensor that detects an oxygen deficiency state, and 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;
A second alarm means such as a buzzer that issues an alarm after a certain period of time has elapsed since the first alarm means is activated and can manually stop the alarm, and the operation of the second alarm means can be stored. An oxygen deficiency safety device for a combustor, comprising a memory circuit, and configured to release the memory when the detection output of the oxygen deficiency sensor returns to a certain value or less.