JPH11351562A - Combustion controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the combustion state from being judged erroneously when coating of an electrically insulating silicon oxide is formed on the surface of a burner or an electrode means. SOLUTION: When a burner 1 is burning normally at a combustion rate corresponding to an inputted combustion rate, theoretical value of potential difference between a second potential detecting means 19 and the burner 1 is derived from the potential difference between first and second potential detecting means 18, 19. A potential difference decision means 23 grasps combustion state by comparing the actually detected potential difference between the second potential detecting means 19 and the burner 1 with the theoretical value and then combustion is controlled by a combustion control means 8.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a combustion control device in a combustion device for burning fuel.

[0002]

2. Description of the Related Art Conventionally, this type of combustion control apparatus is generally described in, for example, JP-A-6-213432, and will be described below with reference to FIGS.

As shown in FIG. 11, the combustion control device includes a burner 1 for burning fuel and a combustion section 1a of the burner 1.
Electrode means 3 arranged to come into contact with the flame 2 formed in the burner 1, voltage supply means 4 for supplying a voltage between the burner 1 and the electrode means 3, and the burner 1 and the electrode means 3
Current detecting means 5 for detecting a current flowing between the two, and a standard current selecting means 6 for selecting a standard current during normal combustion according to the input combustion amount. Current judging means 7 for judging the combustion state by comparing the selected standard current with the current detected by the current detecting means 5, and combustion control means for controlling combustion according to the combustion state judged by the current judging means 7. 8 is provided.

[0004] Liquid fuel such as kerosene is ejected from a nozzle 10 facing the inside of the vaporizer 9 and is heated by a heater 11 embedded in the vaporizer 9 to be vaporized into fuel gas. This fuel gas is mixed with the primary air supplied from the primary air through hole 12 in the carburetor 9 to become a premixed gas, and this premixed gas is used in the combustion section 1 a of the burner 1.
The gas is introduced into the combustion part 1a through a throttle plate 13 disposed between the fuel cell and the vaporizer 9 and a through hole 14 provided in the bottom wall of the combustion part 1a of the burner 1. The pre-mixed gas introduced into the combustion section 1a passes through a flame hole 15 provided on the peripheral wall of the combustion section 1a, and the ignition rod 1 fixed to the burner base 16
It is ignited by 7 to form a flame 2. The electrode means 3 is connected to a burner base 16 of the burner.

The flame 2 formed in the flame 15 is an internal flame 2a formed in the flame hole 15 by a combustion reaction between the premixed fuel gas and the primary air, and the combustion of the premixed gas and the surrounding secondary air. The outer flame 2b is formed outside the inner flame 2a by the reaction. The inner flame 2a and the outer flame 2b contain a large amount of charged particles such as thermally ionized ions and electrons. In particular, the density of the charged particles contained in the inner flame 2a depends on the charged particles contained in the outer flame 2b. It is higher than that.

The electrode means 3 is electrically insulated and fixed to the burner base 16, and its tip 3a is disposed so as to be in contact with the internal flame 2a having a high density of charged particles to flow a large current. . Also, the tip 3a is attached to the tip 3a.
An auxiliary rod 3b made of a material having a different coefficient of thermal expansion from that of the electrode means 3 is provided so that the combustion state can be determined even when an insulating film is formed on a.

The operation of the combustion control by the above-described combustion control device will be described with reference to the flowchart shown in FIG.

First, at step 101, it is confirmed whether or not the operation switch is turned on. If the operation switch is turned on, at step 102, a combustion amount (Qin) is inputted by temperature setting or the like, and combustion is started. Then, in step 103, the standard current (Istd) during normal combustion is selected by the standard current selection means 6 according to the combustion amount (Qin) input in step 102.

When a constant DC voltage is supplied between the burner 1 and the electrode means 3 by the voltage supply means 4, a constant current (Ifr) is generated by charged particles generated according to the input combustion amount (Qin). Flows. Therefore, in step 104, the current (Ifr) is detected by the current detecting means 5. Next, at step 105, the current judging means 7 compares the standard current (Istd) selected at step 103 with the current (Ifr) detected at step 104.

As a result, when the detected current (Ifr) is substantially equal to the standard current (Istd), it is determined that the combustion state is normal, and the process returns to step 101 again, where the detected current (Ifr) is returned.
As long as (r) is substantially equal to the standard current (Istd), the operations from step 101 to step 105 are repeated to continue.

On the other hand, when the combustion state becomes an abnormal combustion state due to oxygen deficiency or the like, the density of the charged particles becomes smaller than that during normal combustion, so that the current (Ifr) decreases. Therefore, in step 106, the detected current (Ifr)
Is compared with the standard current (Istd). If the current is smaller than the standard current, the current judging means 7 judges that there is a possibility of abnormal combustion.
At 08, the supply of fuel is forcibly stopped to stop combustion.

If the detected current (Ifr) is larger than the standard current (Istd) in step 106, the current judging means 7 may have a possibility that the burner 1 and the electrode means 3 are electrically short-circuited. Is determined, a short circuit is displayed in step 109, and in this case, it becomes difficult to accurately detect the combustion state. Therefore, in step 108, the supply of fuel is forcibly stopped to stop the combustion. .

In general, when a volatile organic silicone compound contained in a silicone product such as a hairdressing spray is mixed into combustion air, it causes a chemical reaction with oxygen in the flame 2, and the combustion portion 1 a of the burner 1 and the electrode means. A film of silicon oxide is formed on the surface of No. 3. Since this silicon oxide is electrically insulating, when a silicon oxide film is formed, the resistance between the burner 1 and the electrode means 3 increases, and even when the combustion state is normal, the burner 1 and the electrode The current (Ifr) flowing between the means and 3 decreases. Then, the current (Ifr) decreases as the formed silicon oxide film increases and becomes smaller than the standard current (Istd). When the current (Ifr) decreases, the cause of the decrease in the current (Ifr) is abnormal combustion. It is impossible to judge whether the combustion is caused by the formation of silicon oxide or the formation of silicon oxide. Therefore, it was necessary to stop the combustion, the nameplate, and the fuel supply to forcibly stop the combustion ( Steps 106 to 108).

Therefore, an auxiliary rod 3b made of a material having a different thermal expansion coefficient from that of the electrode means 3 is provided at the tip 3a of the electrode means 3 so that the electrode means 3 and the auxiliary rod 3b have different thermal expansion coefficients. As a result, cracks and pits occur on the surface of the silicon oxide film due to the temperature change, and the portion becomes a new conductive portion, so that the current (Ifr) does not decrease and the surface of the electrode means 3 is electrically insulated. Even if a silicon oxide film is formed, the combustion state can be accurately determined by the current determining means 7.

[0015]

However, in the conventional combustion control device, the auxiliary rod 3b is provided at the tip 3a of the electrode means 3 so that only the surface of the electrode means 3 is coated with an electrically insulating silicon oxide film. Is formed, the current (Ifr) can be reduced, but the silicon oxide film is not only on the surface of the electrode means 3 but also on the burner 1.
Of the current (Ifr)
However, there is a problem that the reduction of the combustion cannot be prevented and the combustion state cannot be determined. That is, if a film of electrically insulating silicon oxide is formed on the surface of the burner 1, the current (Ifr) will decrease even if the combustion state is normal. There is a problem that it is erroneously determined that there is, and the combustion is forcibly stopped (steps 107 and 108).

[0016]

According to the present invention, in order to solve the above-mentioned problems, a voltage is supplied between a burner and an electrode means in contact with a flame formed in the burner to generate a voltage in the flame. The potential value at one point of the flame and the theoretical value of the potential difference between one potential of the flame and the burner are detected when the burner is normally burning at the combustion amount corresponding to the input combustion amount. A theoretical value is theoretically obtained from a potential difference detected between two points of the flame having a functional relationship with each other, and the obtained potential difference is compared with a potential difference actually detected between one potential of the flame and a burner. Thus, the combustion state is determined, and the combustion is controlled according to the combustion state.

Further, the combustion state can be accurately grasped and the combustion can be controlled irrespective of the surface condition of the burner, the electrode means, the means for detecting the potential of the flame, and the like.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention is embodied in the form described in each claim. As described in claim 1, a burner and a flame formed in the burner are provided. A voltage is supplied between the contacting electrode means and a potential generated in the flame is detected at two points, and when the burner is normally burning at a combustion amount corresponding to the input combustion amount, the flame is discharged. The potential difference between one potential and the burner is theoretically obtained from the potential difference detected between two points of the flame, and the obtained potential difference and the potential difference detected between one potential of the flame and the burner are calculated. To determine the combustion state, and control the combustion according to the determined combustion state.

When a predetermined voltage is supplied between the burner and the electrode means which comes into contact with the flame formed in the burner when the combustion conditions such as the amount of combustion are constant, the potential of the flame is reduced by two. The potential difference between the points, and the potential difference between the potential at one point of the flame and the burner is not affected by surface conditions such as the burning part of the burner and the electrode means and the means for detecting the potential of the two points of the flame, It is constant and has a functional relationship.

Therefore, if the combustion state is determined based on the potential difference between two predetermined potentials of the flame and the potential difference between one potential of the flame and the burner, the combustion state can be accurately grasped. it can. For example, even when the electrode means and the burner are formed with an electrically insulating coating such as silicon oxide, the potential difference between two points of the potential generated in the flame, and the potential difference between one potential in the flame and the burner. The potential difference satisfies a certain functional relationship if the combustion conditions such as the amount of combustion are constant, so by using this relationship, the combustion state can be accurately grasped,
In spite of the normal combustion state, there is no more erroneous determination of combustion, and combustion can be accurately controlled.

According to a second aspect of the present invention, there is provided a burner, electrode means disposed in contact with a flame formed on the burner, and a voltage for supplying a voltage between the burner and the electrode means. Supply means, first potential detection means and second potential detection means for detecting the potential of a flame formed in the burner, and a potential difference between the first potential detection means and the second potential detection means (1) , A second potential difference detecting means for detecting a potential difference (2) between the second potential detecting means and the burner, and a burner with a combustion amount corresponding to the input combustion amount. Relational expression selecting means for selecting a relational expression for deriving the theoretical value of the potential difference (2) during normal combustion from the detected potential difference (1), and the theoretical value of the potential difference (2) and the detected potential difference (2). ) To judge the combustion state And position difference determining means, in which a combustion control means for controlling the combustion in accordance with the combustion state is determined by the potential difference determination means.

The electric potential difference (1) and the electric potential difference (2) are defined as follows. If the combustion conditions such as the amount of combustion are constant, the surface of the burner, the electrode means, the electric potential detecting means, etc. is electrically insulating coating such as silicon oxide. Is formed, since a certain relational expression is satisfied, the combustion state can be accurately determined from this relational expression and the detected potential difference (1) and potential difference (2).

Further, as described in claim 3, a current detecting means for detecting a current flowing between the burner and the electrode means, and the burner normally burns at a combustion amount corresponding to the inputted combustion amount. Standard current selecting means for selecting a standard current flowing between the burner and the electrode means at the time, and a current for judging a combustion state from the standard current selected by the standard current selecting means and the current detected by the current detecting means. Judgment means.

The combustion state is determined not only from the relational expression and the potential difference (1) and the potential difference (2), but also from the current flowing between the burner and the electrode means, and the combustion state is determined. Therefore, the safety of the combustion control can be further increased.

When the current detected by the current detecting means is substantially equal to the standard current, the combustion state is judged by the current judging means. When the detected current is smaller than the standard current, the potential difference is judged. The combustion state is determined by means.

When the detected current is substantially equal to the standard current, the combustion state is determined from the current. Therefore, abnormal combustion such as oxygen deficiency can be detected in the same manner as in the conventional case. When abnormal combustion occurs, the relationship between the potential difference (1) and the potential difference (2) changes, so when the detected current is smaller than the standard current,
The combustion state is determined based on the potential difference (1) and the potential difference (2), and even if a coating of an electrical insulator such as silicon oxide is formed, abnormal combustion such as oxygen deficiency can be detected as soon as possible. it can.

Further, when the current detected by the current detecting means reaches the detection limit current of the current detecting means, the combustion is stopped.

Then, the potential difference (1) and the potential difference (2)
If the combustion state is normal, the current flowing between the burner and the electrode means is kept constant until it reaches the detection limit current of the current detection means, so that the current reaches the detection limit current and the potential difference (1 ) And the potential difference (2), when it becomes difficult to determine the combustion state, the combustion is forcibly stopped, so that the safety of the combustion control can be further increased.

Further, the temperature detecting means for detecting the temperature of the carburetor of the burner, and the temperature of the carburetor when the burner normally burns at the combustion amount corresponding to the input combustion amount. It has a standard temperature selecting means for selecting a standard temperature, and a temperature judging means for judging a combustion state from the standard temperature selected by the standard temperature selecting means and the temperature detected by the temperature detecting means.

The temperature of the vaporizer is constant at the amount of combustion.
The combustion state is constant when the combustion state is normal, and decreases during abnormal combustion such as oxygen deficiency. Therefore, the combustion state can be determined based on the temperature of the carburetor. In addition to determining the state, the combustion state is also determined from the temperature of the carburetor, and the combustion state is determined twice, so that the safety of the combustion control can be further increased.

Further, the current detected by the current detecting means is smaller than the standard current, and the potential difference (1) and the potential difference (2) satisfy a predetermined relational expression,
When the vaporizer temperature is almost equal to the standard temperature,
It encourages the discontinuation of use of silicon products.

If the detected current is smaller than the standard current, the potential difference (1) and the second potential difference (2) satisfy a predetermined relational expression, and become substantially equal to the vaporizer temperature and the standard temperature,
Since the combustion state is normal and the silicon oxide film is formed, the user can be notified of discontinuation of use of the silicon product in order to extend the life of the combustion apparatus with respect to the silicon oxide.

[0033]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. Note that the same reference numerals as in the related art are used and the description thereof is omitted.

(Embodiment 1) An embodiment will be described with reference to FIGS.

In FIG. 1, which shows a schematic configuration of the combustion control device according to the first embodiment, an electrode means 3 is disposed so as to contact a flame 2 formed in a combustion portion 1a of a burner 1 for burning fuel. Further, a voltage supply means 4 for supplying a DC voltage is connected between the burner 1 and the electrode means 3.

A first potential detecting means 18 and a second potential detecting means 19 for detecting two different potentials of the flame 2 are provided so as to be in contact with the flame 2.
Then, the first potential difference detecting means 20 for detecting the first potential difference
Is connected between the first potential detecting means 18 and the second potential detecting means 19 to detect a second potential difference.
1 is connected between the second potential detecting means 19 and the burner 1.

Further, there is provided a relational expression selecting means 22 for selecting a relational expression between the first potential difference and the second potential difference according to the input combustion amount, and the selected relational expression and the detected first potential difference and the detected second potential difference. Potential difference determining means 23 for determining the combustion state from the potential difference is provided, and combustion control means 8 for controlling combustion in accordance with the combustion state is provided.

Fuel such as kerosene is supplied to the vaporizer 9,
When heated by the heater 11 embedded therein, it is vaporized to become a fuel gas.
It is squirted into the inside of a. At this time, the primary air is supplied from the primary air through hole 12 by the ejector action, mixed with the fuel gas, and becomes a premixed gas. This premixed gas is ignited by an ignition rod 17 fixed to a burner base 16 when passing through the flame hole 15 through the inside of the combustion section 1 a to form a flame 2. The electrode means 3, the first potential detecting means 18 and the second potential detecting means 19 are arranged so as to be in contact with the inner flame 2a having a high density of charged particles.

In the combustion control apparatus according to the present embodiment having the above-described configuration, when a constant DC voltage is supplied between the burner 1 and the electrode means 3 by the voltage supply means 4,
Charged particles such as thermoionized ions and electrons contained in the flame 2 are accelerated and move toward the burner 1 or the electrode means 3, respectively. The potentials at two different points of the flame 2 are detected by the first potential detecting means 18 and the second potential detecting means 19, respectively.
The first potential difference between the first and second potential detecting means 19 and the second potential difference between the second potential detecting means 19 and the burner 1 are detected by the first potential difference detecting means 20 and the second potential difference detecting means 21, respectively. .

The first potential difference (V12m) and the second potential difference (V2b
m) means that when the combustion amount is constant and the combustion state is normal, a certain relational expression is satisfied. That is, burner 1
If the second potential difference (V2bm) shown when the fuel is burning normally is the theoretical potential difference (V2bc), the theoretical potential difference (V2bc)
Can be expressed as a function of the first potential difference (V12m) as shown by the relational expression (1).

[0041]

(Equation 1)

When the second potential difference (V2bm) detected by the second potential difference detecting means 21 is substantially equal to the theoretical potential difference (V2bc), it is determined that the combustion state is normal, and combustion is continued. When the detected second potential difference (V2bm) is significantly different from the theoretical potential difference (V2bc), it is determined that the combustion state is abnormal, and the combustion is forcibly stopped.

When a volatile organic silicone compound contained in a silicon product such as a hairdressing spray is mixed into the combustion air, a chemical reaction occurs with oxygen in the flame 2, and the combustion section 1 a of the burner 1 and the electrode means 3 An air insulating silicon oxide film is formed on the surface of the substrate. In the case of the conventional combustion control device, the combustion state is determined from the current flowing between the burner 1 and the electrode means 3, so that the current flowing between the burner 1 and the electrode means is normally burnt. When the current decreased to the standard current, it was not possible to discriminate whether the cause of the current decrease was due to abnormal combustion or silicon oxide formation. Therefore, when the current decreases to the standard current for safety, it is determined that the combustion state is abnormal, and the combustion is forcibly stopped.

However, according to the combustion control device of this embodiment, the relation between the theoretical potential difference (V2bc) and the first potential difference (V12m) (1) and the detected first potential difference (V12m) and the Since the combustion state is determined from the two potential differences (V2bm), the combustion state can be accurately determined even when an electrically insulating silicon oxide film is formed.

The operation of the combustion control apparatus according to this embodiment described above will be described with reference to the flowchart shown in FIG.

First, at step 110, it is confirmed whether or not the operation switch is turned on. If it is turned on, at step 111, the combustion amount (Qin) is inputted by temperature setting or the like, and combustion is started. Then, in step 112, the relational expression selecting means 22 calculates the difference between the theoretical potential difference (V2bc) and the first potential difference (V12m) when the combustion is normally performed at the combustion amount corresponding to the combustion amount (Qin) input in step 111. Select relational expression (1).

When a constant DC voltage is supplied between the burner 1 and the electrode means 3 by the voltage supply means 4, step 11
In accordance with the combustion amount (Qin) input in step 1, the first potential difference between the first potential detecting means 18 and the second potential detecting means 19 and between the second potential detecting means 19 and the burner 1 are constant. V12m) and a second potential difference (V2bm). Therefore, in step 113, the first potential difference (V12m)
And the second potential difference (V2bm) are detected by the first potential difference detecting means 20 and the second potential difference detecting means 21, respectively. Then, in step 114, the first potential difference (V12m)
The theoretical potential difference (V2bc) is calculated from the relational expression (1) between the theoretical potential difference (V2bc) and the second potential difference (V2bm) detected in step 113, that is, the second potential difference. The ratio (Z) is calculated from the relational expression (2).

[0048]

(Equation 2)

As described above, when the combustion state is normal, since the second potential difference (V2bm) and the theoretical potential difference (V2bc) are almost equal, the ratio (Z) of the second potential difference is about 1.0. However, in this embodiment, if the ratio (Z) of the second potential difference is in the range of 0.8 to 1.2 in consideration of the measurement accuracy, it is determined that the combustion state is normal. ing.

Next, at step 115, the potential difference judging means 2
In step 3, the ratio (Z) of the second potential difference calculated in step 114 is compared with the second potential difference ratio of 0.8 to 1.2 during normal combustion. Then, step 114
If the ratio (Z) of the second potential difference calculated in the above is in the range of 0.8 to 1.2, it is determined that the combustion state is normal, and the process returns to step 110 again, where the ratio (Z) of the second potential difference is 0.8 ~
As long as the range of 1.2 is maintained, the operations from step 110 to step 115 are repeated to continue.

On the other hand, when the combustion state becomes an abnormal combustion state due to lack of oxygen or the like, the second potential difference (V2bc) and the theoretical potential difference (V2bc)
bc), the ratio of the second potential difference (Z)
Should be less than 0.8 or greater than 1.2. Therefore, when the potential difference determining means 23 determines in step 115 that the ratio (Z) of the second potential difference is smaller than 0.8 or larger than 1.2, there is a possibility of abnormal combustion. Judge, step 116
In step 117, the combustion control means 8 forcibly stops the supply of fuel to stop the combustion.

Next, the results of a study on the characteristics of silicon oxide using a petroleum fan heater equipped with the combustion control device of this embodiment will be described.

Actually, an organosilicone compound contained in a silicone product such as a hairdressing spray is mixed into combustion air, and causes a chemical reaction with oxygen in the flame 2 to cause a burner 1
A coating of electrically insulating silicon oxide is formed on the surface of the combustion part 1a and the electrode means 3 in this example. In this example, a test was conducted by adding about 200 ppm by weight of silicone oil to kerosene which is a liquid fuel. 2,500kc using kerosene
al / h (60 minutes) → Combustion stop (15 minutes) → 650 kcal / h
A continuous combustion test was conducted by a combustion sequence in which (60 minutes) → combustion stop (15 minutes) was one cycle.

A DC voltage of 24 V is supplied between the burner 1 and the electrode means 3 by the voltage supply means 4 so as to supply a voltage between the first potential detecting means 18 and the second potential detecting means 19 and between the first potential detecting means 19 and the second potential detecting means 19. A resistor of 1 MΩ is connected between the burners 1 and the voltage across each resistor is connected to a first potential difference (V12
m) and the second potential difference (V2bm) as the first potential difference means 2
0 and the second potential difference detecting means 21 were used.

As a comparative example, by measuring the current (Ifr) flowing between the burner 1 and the electrode means 3,
A comparison was made of the characteristics with respect to silicon oxide.

First, as a result of examining the characteristics when normal burning was performed using normal kerosene, when the voltage supplied by the voltage supply means 4 was changed, the second potential difference (V2bm)
It has been confirmed that the value changes with respect to the first potential difference (V12m) while maintaining a constant relationship. When the theoretical potential difference (V2bc) of the second potential difference is examined from the silicon oxide characteristic curves obtained at the combustion amounts of 2,500 kcal / h and 650 kcal / h, which will be described later with reference to FIG. 3, the theoretical potential difference (V2bc) Is expressed using the first potential difference (V12m), when the combustion amount is 2,500 kcal / h, the combustion amount 6
It was found that in the case of 50 kcal / h, it can be expressed by the relational expression (4).

[0057]

(Equation 3)

[0058]

(Equation 4)

The combustion amount is 2,500 kcal / h or 650 kc
In the case of normal combustion by al / h, the second potential difference (V2bm) detected in step 113 becomes the same as the theoretical potential difference (V2bc) corresponding to each combustion amount. On the curve shown, the ratio (Z) to the second potential difference is 1.0. The combustion amount is 2,500 kcal /
h, 650 kcal / h, normal current in kerosene (Ifr
0) was about 30 μA and 10 μA, respectively.

After confirming the stability with the normal kerosene described above, the test kerosene was switched to and the characteristic change due to the formation of the silicon oxide film was measured. The results are shown in FIG.
It should be noted that the combustion state does not change even if the test kerosene is switched, the normal combustion is maintained until 10 cycles have elapsed, and after 10 cycles have elapsed, the combustion section 1a of the burner 1
In addition, the surface of the electrode means 3 came to be covered with the silicon oxide film in white.

In FIG. 3, in the case of the embodiment, the ratio (Z) of the second potential difference is represented, and in the case of the comparative example, the detected current (Ifr) is represented by the ratio to the current (Ifr0) in the normal kerosene.

In FIG. 3, the curve (a) is the case where the combustion amount is 2,500 kcal / h in the embodiment, the curve (b) is the case where the combustion amount is 650 kcal / h in the embodiment, and the curve (c) is When the combustion amount is 2,500 kcal / h in the comparative example, the curve (d) indicates that the combustion amount is 650 kcal / h in the comparative example.
Is shown.

The current (Ifr) started to decrease exponentially immediately after switching to the test kerosene, and the combustion amount was 2,500 kc
In both cases of al / h and 650 kcal / h, it is halved in only the second cycle, and up to 30% and 12% of the current (Ifr0) in normal kerosene at 2,500 kcal / h and 650 kcal / h in the 10th cycle, respectively. Diminished.

When the combustion is performed in an oxygen-deficient state with an oxygen concentration of 18%, the current (Ifr) is reduced to about 50% of the current (Ifr0) during normal combustion. In the method of determining the combustion state from the current (Ifr), it is not possible to determine whether the cause of the decrease in the current (Ifr) is caused by abnormal combustion or silicon oxide. It was found that combustion was stopped in only two cycles.

On the other hand, in the method of judging the combustion state from the ratio (Z) of the second potential difference as in the present embodiment, the ratio (Z) after 10 cycles has passed for any combustion amount. It is stable within a range of 1.0 ± 20%, is hardly influenced by the presence of the electrically insulating silicon oxide, and has a stable cycle life that is at least five times longer than that of the comparative example. It turns out.

Next, the oxygen deficiency characteristics in the combustion control device of this embodiment were examined. When the oil fan heater is placed in a closed room and burned at a burn rate of 4,000 kcal / h, and the burner is supplied by the voltage supply means 4, how the 24V second potential difference ratio (Z) is relative to the oxygen concentration The change was measured, and the results are shown in FIG.

When the combustion amount is 4,000 kcal / h, the ratio (Z) of the second potential difference increases as the oxygen concentration decreases, and when the oxygen concentration reaches about 18%, the combustion is performed normally (oxygen concentration). (About 20%) increased to about 1.8 times, and it was found that the combustion control apparatus of the present embodiment can detect an oxygen-deficient state.

From the above results, if the combustion control apparatus according to the present embodiment is used, the combustion state can be accurately determined even when the silicon oxide film is formed on the combustion portion 1a of the burner 1, the electrode means 3, and the like. Combustion in an oxygen-deficient state can also be detected.

(Embodiment 2) Embodiment 2 will be described with reference to FIGS. FIG. 5 showing a schematic configuration of a combustion control device according to the second embodiment is different from that of the first embodiment in that current detection means 5 for detecting a current flowing between the burner 1 and the electrode means 3 and input combustion Standard current selecting means 6 for selecting a standard current when the burner is burning normally according to the amount; and a combustion state based on the standard current selected by the standard current selecting means 6 and the current detected by the current detecting means 5. And a current judging means 7 for judging.

When the detected current is the same as the standard current, the combustion state is judged by the current judging means 7, and when the detected current is smaller than the standard current, the combustion state is judged by the potential difference judging means 23. .

When the detected current reaches the detection limit current of the current detecting means 5, the combustion is stopped.

The components having the same configuration as in the first embodiment are denoted by the same reference numerals, and description thereof is omitted. Although the burner 1 is not shown in detail, it has the same configuration as that of the first embodiment, and this point is the same in the other embodiments.

Next, the operation of the combustion control device in this embodiment will be described with reference to the flowchart shown in FIG.

First, at step 118, it is confirmed whether or not the operation switch is turned on. If the operation switch is turned on, at step 119, the combustion amount (Qin) is inputted by temperature setting or the like, and combustion is started.

Then, in step 120, the standard current (Istd) when the burner is burning normally with the combustion amount (Qin) input by the standard current selection means 6
Is selected. Then, in step 121, the current (Ifr) flowing between the burner 1 and the electrode means 3 is detected by the current detecting means 5, and in step 122, the current (Ifr) detected as the standard current (Istd) by the current determining means 7 is detected. ) And compare. Then, the detected current (Ifr) is equal to the standard current (Ir
When it is determined that the current is substantially equal to (std), it is determined that the combustion state is normal, and the process returns to step 118 again. When the detected current (Ifr) is substantially equal to the standard current (Istd), the process returns to step 118. The operation up to step 122 is repeated.

Further, the current (If
When it is determined that r) is larger than the standard current (Istd), there is a possibility that the burner 1 and the electrode means 3 are electrically short-circuited, and it becomes difficult to accurately determine the combustion state. Therefore, the process jumps to step 130 to forcibly stop the fuel supply.

On the other hand, if it is determined in step 124 that the detected current (Ifr) is smaller than the detection limit current (Ilim) of the current detecting means 5, it becomes difficult to determine the combustion state. , Forcibly shut off the fuel supply.

When the detected current (Ifr) is smaller than the standard current (Istd) and larger than the detection limit current (Ilim), the combustion amount (Qin) input by the relational expression selecting means 22 in step 125. The relational expression (1) between the theoretical potential difference (V2bc) and the first potential difference (V12m) when the burner 1 is burning normally with the combustion amount corresponding to the following is selected.

In step 126, the first potential difference (V
12m) and the second potential difference (V2bm) are detected by the first potential difference detecting means 20 and the second potential difference detecting means 21, respectively. In step 127, the theoretical potential difference (V2bc) is obtained from the relational expression (1) between the first potential difference (V12m) and the second potential difference (V2bc) selected in step 125, and the theoretical potential difference (V2bc) is calculated in step 126. The ratio with the detected second potential difference (V2bm), that is, the ratio of the second potential difference (Z)
Is calculated from the relational expression (2).

Next, at step 128, the potential difference judging means 2
3, the second potential difference ratio (Z) calculated in step 127 is compared with the second potential difference ratio (0.8 to 1.2) during normal combustion. And step 12
If the ratio (Z) of the second potential difference calculated in step 7 is in the range of 0.8 to 1.2, it is determined that the combustion state is normal, and the process returns to step 118 again to repeat the operation, and Step 1 as long as the ratio (Z) is 0.8 to 1.2
The operations from 18 to 128 are repeated.

On the other hand, if it is determined in step 128 that the ratio (Z) of the second potential difference is smaller than 0.8 or larger than 1.2, there is a possibility of abnormal combustion. To display abnormal combustion, and in step 130, the supply of fuel is forcibly stopped by the combustion control means 8.

According to the combustion control device of this embodiment, not only the combustion state is determined from the relationship between the first potential difference (V12m) and the second potential difference (V2bc), but also the flow between the burner 1 and the electrode means 3 is determined. Since the combustion state is also determined from the current (Ifr) and the combustion state is double-checked, the safety can be further increased.

The relationship between the first potential difference (V12m) and the second potential difference (V2bm) is as follows: if the combustion state is normal, the current (Ifr) flowing between the burner 1 and the electrode means 3 The current is kept constant until the detection limit current (Ilim) is reached, the current (Ifr) reaches the detection limit current (Ilim), and the combustion state is determined from the first potential difference (V12m) and the second potential difference (V2bm). If it becomes difficult, the combustion is forcibly stopped, so that the safety of the combustion control can be further increased.

(Embodiment 3) Embodiment 3 will be described with reference to FIGS. 9 shows a schematic configuration of a combustion control device according to a third embodiment.

FIG. 7 is different from the first embodiment in that the temperature detector 24 for detecting the temperature of the carburetor 9 and the case where the burner normally burns at a combustion amount corresponding to the input combustion amount. A standard temperature selecting means 25 for selecting a standard temperature of the vaporizer 9 and a temperature judging means 26 for judging a combustion state from the standard temperature and the temperature of the vaporizer 9 detected by the temperature detecting means 24 are added. That is the point.

The components having the same configuration as in the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

Next, the operation of the combustion control device according to the embodiment will be described with reference to the flowchart shown in FIG.

First, in step 131, it is confirmed whether or not the operation switch is turned on. If the operation switch is turned on, in step 132, the combustion amount (Qin) is inputted by temperature setting or the like, and combustion is started. Then, in step 133, the theoretical potential difference (V) when normally burning with the combustion amount (Qin) corresponding to the combustion amount (Qin) input by the relational expression selecting means 22.
2bc) and the first potential difference (V12m) are selected.

In step 134, the first potential difference (V12m) and the second potential difference (V2bm) are detected by the first potential difference detecting means 20 and the second potential difference detecting means 21, respectively.

Then, in step 135, step 13
The first potential difference (V12m) and the second potential difference (V2b
The theoretical potential difference (V2bc) is obtained from the relational expression (1) with c),
Further, the ratio between the theoretical potential difference (V2bc) and the second potential difference (V2bm) detected in step 134, that is, the ratio (Z) of the second potential difference is calculated from the relational expression (2).

Next, at step 136, the potential difference judging means 2
3, the second potential difference ratio (Z) calculated in step 135 is compared with the second potential difference ratio (0.8 to 1.2) during normal combustion. And step 13
If the ratio (Z) of the second potential difference calculated in step 6 is determined to be smaller than 0.8 or larger than 1.2, there is a possibility of abnormal combustion. 8 forcibly stops the fuel supply.

On the other hand, if the ratio (Z) of the second potential difference is in the range of 0.8 to 1.2 in step 136, it is determined that the combustion state is normal, and the process proceeds to step 137. In step 137, the standard temperature (Tst) of the carburetor 9 when the burner is burning normally with the combustion amount (Qin) input by the standard temperature selection means 25.
Select d).

At step 138, the actual temperature (T) of the vaporizer 9 is detected by the temperature detecting means 24. In step 139, the standard temperature (Tstd) of the vaporizer 9 is compared with the actual temperature (T) detected in step 138. If the detected temperature (T) is substantially equal to the standard temperature (Tstd), the combustion is in a normal state, and therefore, Step 13 is repeated.
Returning to step 1, as long as the detected temperature (T) is substantially equal to the standard temperature (Tstd), step 131 to step 1
The operations up to 39 are repeated.

On the other hand, if the vaporizer temperature (T) is significantly different from the standard temperature (Tstd) in step 139, there is a possibility of abnormal combustion. Therefore, after displaying abnormal combustion in step 140, the combustion control is performed in step 141. The means 8 forcibly stops the supply of fuel.

According to the combustion control apparatus of the present embodiment, the temperature of the vaporizer 9 is constant when the combustion amount is constant, is constant when the combustion state is normal, and decreases when abnormal combustion such as oxygen deficiency occurs. Since it is used, the combustion state can be determined. Then, the first potential difference (V12m) and the second potential difference (V12m)
2bm), the combustion state is judged not only from the temperature of the vaporizer 9 but also from the temperature of the carburetor 9, and the combustion state is double-checked, so that the safety of the combustion control can be further increased.

(Embodiment 4) Embodiment 4 will be described with reference to FIGS. FIG. 9 showing a schematic configuration of a combustion control device according to the fourth embodiment is different from the first embodiment in that a current detection unit 5 for detecting a current flowing between the burner 1 and the electrode unit 3 and the input combustion amount are different. Standard current selecting means 6 for selecting a standard current when the fuel is burning normally with a corresponding amount of combustion, current determining means 7 for determining a combustion state from the standard current and the current detected by the current detecting means 5, Temperature detecting means 2 for detecting the temperature of vaporizer 9
4, a standard temperature selecting means 25 for selecting a standard temperature of the carburetor 9 when the burner is burning normally with a combustion amount corresponding to the input combustion amount, and detection by the standard temperature and concentration detecting means 24. In this configuration, a temperature determining means 26 for determining a combustion state based on the temperature of the carburetor and the temperature of the carburetor is added.

If the current detected by the current detecting means 5 is smaller than the standard current, the first potential difference and the second potential difference satisfy a predetermined relational expression, and the temperature of the vaporizer 9 is at the standard temperature, the silicon product They are encouraged to discontinue use.

The same components as those in the following case are denoted by the same reference numerals, and description thereof is omitted.

The operation of the combustion control device according to this embodiment will be described with reference to the flowchart shown in FIG.

First, at step 142, it is confirmed whether or not the operation switch is turned on. If the operation switch is turned on, at step 143, a combustion amount (Qin) is inputted by temperature setting or the like, and combustion is started.

Next, in step 144, the standard current (Istd) during normal combustion at the combustion amount corresponding to the combustion amount (Qin) input by the standard current selection means 6 is selected. Then, at step 145, the current detecting means 5
In step 146, the current (Ifr) is detected by the current judging means 7 and the standard current (Istd) selected in step 144 is compared with the current (Ifr) detected in step 145. If it is almost equal to (Istd), it is determined that the combustion state is normal,
Returning to step 142 again, the operations from step 142 to step 146 are repeated as long as the detected current (Ifr) and the standard current (Istd) are at least substantially equal.

In step 147, the detected current (If
When r) is larger than the standard current (Istd), there is a possibility that the burner 1 and the electrode means 3 are electrically short-circuited,
Since it is difficult to accurately determine the combustion state, the routine jumps to step 157, in which the supply of fuel is forcibly stopped.

In step 148, if the detected current (Ifr) is smaller than the detection limit current (Ilim) of the current detecting means 5, it becomes difficult to determine the combustion state. Forcibly stop supply.

The detected current (Ifr) is the standard current (I
If the burner is burning normally with a combustion amount corresponding to the combustion amount (Qin) input by the relational expression selecting means 22 in step 149, if the burner is normally smaller than the detection limit current (Ilim). The relational expression (1) between the theoretical potential difference (V2bc) and the first potential difference (V12m) is selected.

In step 150, the first potential difference (V
12m) and the second potential difference (V2bm) are detected by the first potential difference detecting means 20 and the second potential difference detecting means 21, respectively. In step 151, the relational expression (1) selected in step 149 and the first potential difference detected in step 150 are detected. Potential difference (V
12m), the theoretical potential difference (V2bc) is calculated from the relationship (2), and the ratio of the second potential difference (V2bm) detected in step 150 and the calculated theoretical potential difference (V2bc), that is, the ratio (Z) of the second potential difference, is calculated from the relational expression (2). calculate.

Next, at step 152, the potential difference judging means 2
The ratio (Z) of the second potential difference calculated in step (3) is used as the ratio of the second potential difference when the burner is burning normally.
Compare with 2). If it is determined that the ratio (Z) of the second potential difference calculated in step 151 is smaller than 0.8 or larger than 1.2, there is a possibility of abnormal combustion. The supply of fuel is forcibly stopped by the combustion control means 8.

On the other hand, if the ratio (Z) of the second potential difference is in the range of 0.8 to 1.2 in step 152, it is determined that the combustion state is normal, and the process proceeds to step 153. Then, in step 153, the standard temperature (Ts) of the carburetor 9 when the burner is burning normally with the combustion amount (Qin) input by the standard temperature selection means 25.
Select td).

At step 154, the actual temperature (T) of the vaporizer 9 is detected by the temperature detecting means 24. Then, in step 155, the standard temperature (Tstd) is compared with the detected temperature (T). When the detected temperature (T) of the vaporizer 9 is substantially equal to the standard temperature (Tstd), the combustion is in a normal state and the silicon oxide is being formed.
After informing the user in step 158 that the use of the silicon product has been prohibited, the process returns to step 142 again, and the operations from step 142 to step 155 are performed as long as the temperature (T) of the vaporizer 9 is substantially equal to the standard temperature (Tstd). Is repeated.

On the other hand, in step 155, if the temperature (T) of the vaporizer 9 is significantly different from the standard temperature (Tstd),
Since there is a possibility of abnormal combustion, after displaying abnormal combustion in step 156, the supply of fuel is forcibly stopped by the combustion control means 8 in step 157.

According to the combustion apparatus of this embodiment, not only the combustion state is determined from the first potential difference (V12m) and the second potential difference (V2bm), but also the current flowing between the burner 1 and the electrode means 3 and the vaporization are determined. Since the combustion state is also determined from the temperature (T) of the vessel 9 and the combustion state is confirmed threefold, the safety of the combustion control can be further increased.

The detected current (Ifr) is equal to the standard current (Is
td), the first potential difference (V12m) and the second potential difference (V2m
bm) satisfies the relational expression, and the temperature (T) of the vaporizer 9 is the standard temperature
If it is almost equal to (Istd), the combustion state is normal,
Since the silicon oxide film is in the state of being formed, the user can be notified of discontinuance of use of the silicon product in order to extend the life of the combustion device with respect to the silicon oxide.

[0112]

According to the combustion control apparatus of the present invention configured as described above, the following effects can be obtained.

According to the first aspect, when the burner is burning normally, the potential difference between two points of the potential generated in the flame formed in the burner and the potential difference between the potential at one point of the flame and the burner. Since the combustion state is grasped by utilizing the fact that it becomes constant irrespective of the surface state of the means for detecting the potential or the burner, without being affected by the surface state of the means for detecting the potential or the burner, Combustion can be controlled accurately.

According to the second aspect, the first potential difference between the first potential detecting means and the second potential detecting means (1) and the potential difference between the second potential detecting means and the burner (2). If the combustion conditions such as the amount of combustion are constant, even if an electrically insulating silicon oxide is formed on the surface of the burner or the electrode means,
Since a certain relational expression is satisfied, the combustion state can be determined from the detected potential difference (1) and potential difference (2).

According to the third aspect, not only the combustion state is determined from the potential difference (1) and the potential difference (2), but also the combustion state is determined from the current flowing between the burner and the electrode means. Thus, the combustion state can be confirmed, and the safety of combustion control can be increased.

According to the fourth aspect, when the detected current is substantially equal to the standard current, the combustion state is determined from the current, so that abnormal combustion such as oxygen deficiency can be detected. When the current is smaller than the current, the combustion state is determined from the potential difference (1) and the potential difference (2) if the combustion state is determined based on the current. Therefore, even if a silicon oxide film is formed on a burner or the like, an abnormality such as oxygen deficiency occurs. Combustion can be detected.

According to the fifth aspect, the relationship between the potential difference (1) and the potential difference (2) is such that when the combustion state is normal, the current flowing between the burner and the electrode means is equal to the detection limit current of the current detection means. When the current reaches the detection limit current and it becomes difficult to determine the combustion state from the potential difference (1) and the potential difference (2), the combustion is forcibly stopped. Security can be increased.

According to the sixth aspect of the present invention, the temperature of the vaporizer is constant when the amount of combustion is constant, and is constant when the combustion state is normal, and is reduced during abnormal combustion such as oxygen deficiency. Since the state is determined, not only the combustion state is determined from the potential difference (1) and the potential difference (2), but also the combustion state is determined from the temperature of the carburetor. Safety can be increased.

Further, according to claim 7, if the detected current is smaller than the standard current, the potential difference (1) and the potential difference (2) satisfy a predetermined relational expression, and the temperature of the vaporizer is equal to the standard temperature. Since the combustion state is normal and the silicon oxide film is formed, the user can be notified of the discontinuation of use of the silicon product, and the life of the combustion apparatus with respect to the silicon oxide can be extended.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a combustion control device according to a first embodiment of the present invention.

FIG. 2 is a flowchart showing the operation of the combustion control device.

FIG. 3 is a characteristic diagram of silicon oxide of the combustion control device.

FIG. 4 is an oxygen deficiency characteristic diagram of the combustion control device.

FIG. 5 is a schematic configuration diagram of a combustion control device according to a second embodiment of the present invention.

FIG. 6 is a flowchart showing the operation of the combustion control device.

FIG. 7 is a schematic configuration diagram of a combustion control device according to a third embodiment of the present invention.

FIG. 8 is a flowchart showing the operation of the combustion control device.

FIG. 9 is a schematic configuration diagram of a combustion control device according to a fourth embodiment of the present invention.

FIG. 10 is a flowchart showing the operation of the combustion control device.

FIG. 11 is a schematic configuration diagram of a conventional combustion control device.

FIG. 12 is a flowchart showing the operation of the combustion control device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Burner 2 Flame 3 Electrode means 4 Voltage supply means 5 Current detection means 6 Standard current selection means 7 Current judgment means 8 Combustion control means 9 Vaporizer 18 First potential detection means 19 Second potential detection means 20 First potential difference detection means 21 Second potential difference detecting means 22 Relational expression selecting means 23 Potential difference determining means 24 Temperature detecting means 25 Standard temperature selecting means 26 Temperature determining means

Claims (7)

[Claims] 1. A voltage is supplied between a burner and an electrode means which comes into contact with a flame formed in the burner, and a potential generated in the flame is detected at two points, and corresponds to the input combustion amount. When the burner is burning normally at the amount of combustion, the potential difference between one potential of the flame and the burner is theoretically obtained from the potential difference detected between two points of the flame, and the obtained potential difference And a potential difference detected between the burner and one of the potentials of the flame to determine a combustion state, and control combustion in accordance with the combustion state. 2. A burner, electrode means for contacting a flame formed on the burner, voltage supply means for supplying a voltage between the burner and the electrode means, and a potential of the flame formed on the burner. Potential detecting means and second potential detecting means for detecting a potential difference; a first potential difference detecting means for detecting a potential difference (1) between the first potential detecting means and the second potential detecting means; A second potential difference detecting means for detecting a potential difference (2) between the potential detecting means and the burner; and a second potential difference detecting means for detecting a potential difference (2) when the burner is normally burning at a combustion amount corresponding to the input combustion amount. Relational expression selecting means for selecting a relational expression deriving a theoretical value from the potential difference (1) detected by the first potential difference detecting means, and a theoretical value of the potential difference (2) and a potential difference detected by the second potential difference detecting means Starting from (2) A potential difference determination means for disconnection, the combustion control device and a combustion control means for controlling the combustion in accordance with the combustion state is determined by the potentiometric determination means. 3. A current detecting means for detecting a current flowing between the burner and the electrode means, and a current detecting means for detecting a current flowing between the burner and the electrode means when the burner is burning normally with a combustion amount corresponding to the input combustion amount. 3. A standard current selecting means for selecting a standard current flowing therethrough, and a current judging means for judging a combustion state from the standard current selected by the standard current selecting means and the current detected by the current detecting means. The combustion control device according to any one of the preceding claims. 4. When the current detected by the current detecting means is substantially equal to the standard current, the combustion state is judged by the current judging means. When the detected current is smaller than the standard current, the combustion state is judged by the potential difference judging means. Item 4. The combustion control device according to item 2 or 3. 5. The combustion control device according to claim 2, wherein the combustion is stopped when a current detected by the current detection means reaches a detection limit current of the current detection means. 6. A temperature detecting means for detecting a temperature of a carburetor provided in a burner, and a standard temperature of the carburetor when the burner is burning normally with a combustion amount corresponding to the input combustion amount. 3. A standard temperature selecting means, and a temperature judging means for judging a combustion state from a standard temperature selected by the standard temperature selecting means and a temperature detected by the temperature detecting means.
The combustion control device according to any one of the preceding claims. 7. When the current detected by the current detecting means is smaller than the standard current, the potential difference (1) and the potential difference (2) satisfy a predetermined relational expression, and the temperature of the vaporizer is substantially equal to the standard temperature. 7. The combustion control device according to claim 2, wherein a display prompting to stop using the silicon product is displayed.