JP2002048337A - LOW NOx COMBUSTOR - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the generation of NOx and to secure variable burning rate by thinning the fuel concentration of the lean fuel flames in a low NOx combustion apparatus. SOLUTION: A low NOx combustor is provided with a lean fuel burner port 12 feeding a lean air-fuel mixture communicating with a lean gas chamber 11, a first flame port 14 arranged near the lean fuel burner port communicating with a first air-fuel mixture chamber 13 adjacent to the lean gas chamber and a second burner port 17 arranged near the first burner port communicating with a second air-fuel mixture chamber 16 adjacent to the first air-fuel mixture chamber, wherein the fuel concentration of the gas of the first air-fuel mixture chamber is controlled to be higher than the fuel concentration of the gas of the second air-fuel mixture chamber 16, and the flow capacities of the lean air-fuel mixture, a first air-fuel mixture and a second air fuel mixture are controlled at a same rate. Therefore, substance dispersion from a rich air-fuel mixture can be continued stably, as the flow pattern of the lean air-fuel mixture gas ejected form the lean air-fuel mixture burner port 12 resembles the flow pattern of the rich air-fuel mixture gas ejected from the first burner port 14 and the difference of the concentrations of the gases is maintained, and the ultra-low NOx can be realized by reducing the fuel concentration of the lean air-fuel mixture.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a combustion apparatus mainly for domestic or commercial use, and particularly to a combustion apparatus in which NOx in exhaust gas is significantly reduced to achieve cleanness.

[0002]

2. Description of the Related Art As a first example of this kind of conventional low NOx combustion apparatus, there is one disclosed in Japanese Patent Application Laid-Open No. 1-219406. The low NOx combustion device is configured such that light burners for supplying a lean air-fuel mixture into a combustion chamber and rich burners for supplying a rich air-fuel mixture to both sides of the light burner are alternately arranged.

[0003] The lean mixture supplied from the lean burner has a low flame temperature in the combustion chamber and thus has low NOx, but itself forms an unstable lean flame. The rich air-fuel mixture supplied from the rich burner has a high flame temperature in the combustion chamber and therefore has high NOx, but itself forms a stable rich flame,
By supplying thermal energy to the adjacent lean flame to promote the combustion reaction, a stable so-called lean-burn combustion as a whole is realized. Then, the combustion ratio of the light burner is set to be larger than that of the rich burner, and the NOx is reduced as a whole.

[0004] As a second example, Japanese Patent Publication No. 57-12923 discloses an all-primary combustion apparatus in which the concentration of air-fuel mixture is changed stepwise to reduce NOx. In this device, as shown in FIG. 8, the lean mixture chamber 3 is communicated from the central flame opening 1 to the peripheral flame opening 2 by the communication port 4, and the fuel is gradually supplied so that the lean mixture chamber 3 It is configured to gradually increase the concentration of the air-fuel mixture. Then, the ultra-lean flame formed at the central flame opening portion 1 is stabilized to some extent by a peripheral flame having a relatively high concentration, and is stabilized by a lean flame having a gradually increasing concentration.
x combustion is realized.

As a third example, Japanese Patent Application Laid-Open No. 7-4640 discloses a combustion apparatus in which a temperature detecting element is mounted above the light and rich flame opening in the light and rich combustion and the output of the temperature detecting element is detected. In this apparatus, as shown in FIG. 9, a dense burner 5 and a light burner 6 are juxtaposed at intervals, and secondary air flows between them. By providing the temperature detecting element 7 for detecting the air ratio, the air ratio of the combustion air can be detected, and the temperature of the temperature detecting element itself does not become high, so that the durability is improved.

[0006]

However, in the low NOx combustion apparatus of the first conventional example, the lean flame is stabilized by the thermal energy of the rich flame.
If the burn rate of the rich burner is reduced, the lean flame becomes unstable, and there is a problem that there is a limit in increasing the burn rate of the lean mixture and further reducing NOx.

The low N in the second example shown in FIG.
In the Ox combustion device, a lean flame that performs all primary combustion is formed in both the central flame opening 1 and the peripheral flame opening 2, and is effective for stabilizing a lean flame such as a rich flame in the lean combustion. Since there is no means, a very delicate balance of fuel and air supply is required, and therefore, the configuration of the communication port 4 also requires high-precision processing. In addition, high-speed, high-precision air and fuel flow control was required. Further, there is a problem that a variable adjustment width of the combustion amount is small because an unstable lean flame is formed by the all primary combustion, and it is difficult to cope with a high-speed change of the combustion amount because the fuel supply balance is easily lost. Further, in the low NOx combustion apparatus of the third example shown in FIG. 10, the combustion air ratio and the temperature are not the actual high-temperature combustion flame, but the temperature detection element detects the temperature balanced by the radiation of the flame and the cooling by the secondary air. Although there is a correlation with the output of the element, there is a problem that the measurement accuracy cannot be maintained because the influence of other influences is easily detected and the heat radiation from the high-temperature flame is detected at a low temperature.

In particular, errors due to fluctuations in the secondary air are large. That is, the sum of primary air and secondary air is combustion air, but when the secondary air volume increases compared to primary air due to changes in flow resistance due to outside air temperature, burner thermal deformation, passage temperature rise, etc. The temperature element determines that the combustion air ratio is larger than a predetermined value, and controls the air to be reduced, so that the flame becomes insufficient and yellow soot occurs. Conversely, when the amount of secondary air decreases compared to the primary air, the temperature element judges that the combustion air ratio is lower than the predetermined value and controls the air to increase, and the flame becomes excessive and the non-combustible component odor due to blow-off is generated. I do.

In addition, since a temperature element is provided between the high-temperature flame and the low-temperature cooling air, the temperature gradient is very large, the output varies greatly depending on the position of the temperature element, and it is difficult to maintain the position with high precision in manufacturing. Was.

[0010]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a lean flame port which communicates with a lean chamber and supplies a lean air-fuel mixture into a combustion chamber, and a first air-fuel chamber adjacent to the lean chamber. A first flame port provided in close proximity to the lean flame port, and a second flame port provided in proximity to the first flame port in communication with a second mixture chamber adjacent to the first mixture chamber. A second combustion chamber having a concentration higher than that of the second mixture chamber, and a plurality of temperature detection means provided above the lean flame port; The supply amount or the combustion air supply amount is increased or decreased.

Here, as a result of a detailed investigation of the flame base structure that determines the stability of the lean flame, which is the point of solving the problem, the rich flame formed on the second flame port by the above configuration is supplied from the first flame port. The rich mixture is subjected to thermal decomposition, a large amount of chemically active intermediate products are generated, and furthermore, it is supplied to the base of the lean flame outlet by substance diffusion, and the combustion reaction is actively performed in the minute space of the base. It was found that a "high temperature and high reaction zone" was formed, and thereby the lean flame was stabilized. As inferred from Hooke's law, which is the basis of material diffusion, the higher the concentration difference between the first mixture chamber and the lean chamber, and the smaller the jet flow velocity from the first flame outlet, the higher the temperature and reaction zone. Was easily formed.
Further, the rich mixture supplied from the second flame port forms a stable rich flame by itself and promotes the reaction of the lean flame, so that the combustion reaction is completed.

Most of the combustion is the combustion of a lean gas mixture from a lean flame port. In this combustion state, in order to suppress the generation of thermal NOx and reduce NOx, the combustion air ratio is set to be larger (approximately m = 1.4 to 2.0) than that of a general flame to reduce the flame temperature. I'm trying. For this reason, when the combustion air ratio is further increased, the flame length is increased, and blow-off tends to occur in a part. Therefore, if a plurality of temperature detectors are provided above the lean flame outlet, the air ratio during the lean combustion can be directly detected, and the output of the temperature detector increases or decreases the fuel supply amount or the combustion air supply amount. As a result, the optimum combustion air ratio can always be maintained.

Therefore, since the combustion ratio of the lean air-fuel mixture can be further increased and the concentration of the lean air-fuel mixture can be reduced, the NOx can be further reduced, and in this state, the variable width of the combustion amount can be expanded. Stable combustion can be realized by following high-speed fluctuations of air. Such a combustion system that supplies air-fuel mixtures having different concentrations to achieve ultra-low NOx combustion is hereinafter referred to as "multi-concentration combustion" in order to distinguish it from the conventional lean-burn combustion.

[0014]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.
The x-burning device is provided in close proximity to the lean flame port which communicates with the lean chamber and communicates the lean mixture to flow out and into the combustion chamber and communicates with the first mixture chamber adjacent to the lean chamber. A first flame port, having a second flame port provided in close proximity to the first flame port and communicating with a second gas mixture chamber adjacent to the first gas mixture chamber; In addition to making the concentration higher than the concentration of the second mixture chamber, a plurality of temperature detecting means are provided above the lean flame port, so that the air ratio during the lean combustion can be directly detected. Alternatively, the configuration is such that the supply amount of combustion air is increased or decreased, so that an optimum combustion air ratio can be always maintained. For this reason, the combustion ratio of the lean air-fuel mixture is increased, and the concentration of the lean air-fuel mixture is reduced to reduce the ultra-low NO.
x can be achieved, and a large variable width of the combustion amount for maintaining good combustion can be secured.

According to a second aspect of the present invention, there is provided a low NOx combustion apparatus configured to increase or decrease a fuel supply amount or a combustion air supply amount in accordance with a difference between temperatures detected by temperature detecting means, and detect a state of a flame. To adjust the combustion air ratio.
The flame having a large air ratio is generated when the combustion speed is balanced with the mixed gas ejected from the flame outlet, and the combustion is completed when the reaction is completed. The combustion speed that determines the position of the flame is determined by the combustion air ratio. A plurality of temperature detecting means are provided along the gas flow in the flame port, and the position of the flame can be determined based on the difference between the outputs. Therefore, the combustion air ratio can be optimally adjusted, and ultra-low NOx combustion can be realized.

A low NOx combustion apparatus according to a third aspect of the present invention includes a comparison control unit connected to a temperature detecting means, the comparison control unit storing a mutual target temperature difference value,
It has a configuration comprising a calculation and comparison unit for comparing the difference between the values detected by the temperature detecting means with each other, and a control unit for increasing or decreasing the fuel supply amount or the combustion air supply amount according to the value. As a result, the target temperature difference value corresponding to the optimum air ratio is stored in the storage unit in advance, and this value is compared with the mutual difference between the values detected by the temperature detection means in the operation comparison unit. By increasing or decreasing the supply amount or the combustion air supply amount by the control unit, good combustion can always be maintained.

The low NOx combustion apparatus according to claim 4 of the present invention is configured to increase or decrease the fuel supply amount or the combustion air supply amount in accordance with the mutual ratio of the temperatures detected by the temperature detecting means. In this case, the combustion air ratio can be adjusted by detecting the state of the flame. The jetting speed of the mixed gas changes due to the increase or decrease in the amount of combustion, and the place where the flame is generated and the place where the reaction is completed move. A plurality of temperature detecting means are provided along the gas flow of the flame outlet, and the sensitivity of the flame is improved more than the mutual difference by the ratio of the outputs, so that the position of the flame can be clearly determined. Therefore, the combustion air ratio can be optimally adjusted according to the change in the combustion amount, and ultra-low NOx combustion can be realized.

A low NOx combustion apparatus according to a fifth aspect of the present invention is provided with a comparison control unit connected to a temperature detection means, the comparison control unit storing a mutual target temperature ratio value, and the temperature detection unit. The calculation unit is configured to compare the value detected by the means with the mutual ratio value, and the control unit increases or decreases the fuel supply amount or the combustion air supply amount according to the value. Thus, a plurality of temperature detecting means are provided along the gas flow in the flame outlet, and the sensitivity of the output is improved more than the mutual difference by the ratio of the outputs, so that the position of the flame can be clearly determined. Therefore, it is possible to optimally adjust the combustion air ratio in accordance with the change in the combustion amount, and further, compare the target temperature difference value according to the optimum air ratio stored in the storage unit with the operation comparison unit, By increasing or decreasing the fuel supply amount or the combustion air supply amount in accordance with this value, good combustion can always be maintained in accordance with the change in the combustion amount, and even when the combustion amount is small, the combustion ratio of the lean air-fuel mixture can be reduced. Ultra-low NOx can be achieved by increasing the concentration and decreasing the concentration of the lean mixture.

A low NOx combustion apparatus according to a sixth aspect of the present invention communicates with a lean flame port which communicates with a lean chamber and supplies and supplies a lean air-fuel mixture into the combustion chamber, and a first air-fuel mixture chamber adjacent to the lean chamber. And a first flame port provided in close proximity to the lean flame port,
A second flame port provided in close proximity to the first flame port in communication with a second gas mixture chamber adjacent to the first gas mixture chamber, wherein the concentration of the first gas mixture chamber is controlled by the second mixing chamber; A plurality of flame detection means are provided above the lean flame port, and the air ratio can be directly detected from the lean combustion state with high responsiveness.The output of the flame detection means enables the fuel supply amount or the fuel supply amount to be increased. With the configuration in which the air supply amount is increased or decreased, the optimum combustion air ratio can always be maintained with good responsiveness. For this reason,
The combustion ratio of the lean air-fuel mixture can be increased, and the concentration of the lean air-fuel mixture can be reduced to achieve ultra-low NOx, and the variable range of the amount of combustion that maintains good combustion even when the amount of combustion is changed is increased. Can be secured.

In the low NOx combustion apparatus according to the seventh aspect of the present invention, the fuel supply amount or the combustion air supply amount can be increased or decreased according to the mutual difference between the outputs from the flame detecting means. A flame with a large air ratio is completed when the flame is generated from the point where the combustion speed is balanced with the mixed gas ejected from the flame outlet and the reaction is completed. The combustion speed that determines the position of the flame is determined by the combustion air ratio. A plurality of flame detection means are provided along the gas flow in the flame outlet, and the position of the flame can be quickly determined by the difference between the outputs. Therefore, the combustion air ratio can be optimally adjusted instantaneously, and ultra-low NOx combustion can be realized.

The low NOx combustion device according to claim 8 of the present invention includes a comparison control unit connected to the flame detection means, the comparison control unit storing a mutual target output difference value,
It is configured to include a calculation and comparison unit that compares the difference between the values detected by the flame detection unit and a control unit that increases or decreases the fuel supply amount or the combustion air supply amount according to the value. As a result, the target output difference value corresponding to the optimum air ratio is stored in the storage unit in advance, and this value is compared with the mutual difference between the detected value from the flame detection unit having high responsiveness in the operation comparison unit. By increasing or decreasing the fuel supply amount or the combustion air supply amount in accordance with the value, the responsiveness is quick and good combustion can always be maintained.

In the low NOx combustion apparatus according to the ninth aspect of the present invention, the fuel supply amount or the combustion air supply amount can be adjusted by increasing or decreasing according to the mutual ratio of the outputs from the flame detecting means.
When the injection speed of the mixed gas changes due to the increase or decrease of the combustion amount,
The place where the flame is generated and the place where the reaction ends move. A plurality of flame detecting means are provided along the gas flow of the flame outlet, and the sensitivity of the flame is improved more than the mutual difference by the ratio of the outputs, so that the flame position can be clearly identified and the response can be quickly determined. For that reason,
It becomes possible to quickly and optimally adjust the combustion air ratio in response to a change in the amount of combustion, thereby realizing ultra-low NOx combustion.

A low NOx combustion apparatus according to a tenth aspect of the present invention includes a comparison control unit connected to the flame detection means, the comparison control unit storing a mutual target output ratio value, and the flame detection unit. The calculation unit is configured to compare the value detected by the means with the mutual ratio value, and the control unit increases or decreases the fuel supply amount or the combustion air supply amount according to the value. Thereby, a plurality of flame detecting means are provided along the gas flow of the flame outlet, and the sensitivity of the flame is improved more than the mutual difference by the ratio of the outputs, so that the response is quick and the position of the flame can be clearly identified. Therefore, it becomes possible to quickly and optimally adjust the combustion air ratio in response to a change in the combustion amount.
The target output difference value corresponding to the optimum air ratio stored in the storage unit is compared with the operation comparison unit, and the fuel supply amount or the combustion air supply amount is increased / decreased by the control unit according to this value, so that quick response is achieved. Good combustion can always be maintained in response to changes in combustion volume,
Even when the amount of combustion is increasing or decreasing according to the load or when the amount of combustion is small, the combustion ratio of the lean air-fuel mixture can be increased, and the concentration of the lean air-fuel mixture can be reduced to achieve ultra-low NOx.

The low NOx combustion apparatus according to claim 11 of the present invention stores a value obtained by increasing or decreasing a fuel supply amount or a combustion air supply amount by comparing with a value detected by a temperature detecting means or a flame detecting means during combustion. And the next combustion is started with this value. As a result, combustion can be started with the optimal air-fuel ratio, the ignition can be reliably performed, and the generation of unburned components can be suppressed. Reliability can be ensured.

According to the low NOx combustion apparatus of the twelfth aspect of the present invention, the air ratio of the flame at the time of ignition can be detected more accurately by the configuration in which the combustion amount and the air amount are constant for a certain period of time from the start of combustion. Since the temperature of the flame at the time of ignition rises rapidly and the combustion reaction is not equilibrium, it is difficult to discriminate between a change in the air ratio and a change in the combustion amount. Therefore, the influence of the air ratio can be detected by fixing the amount of combustion and the amount of air to a certain amount for a certain time. For this reason, the generation of unburned components can be further suppressed.

[0026]

Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1) FIG. 1 is an overall sectional view showing a low NOx combustion apparatus according to Embodiment 1 of the present invention, and FIG. 2 is a partially enlarged view showing a flame formation state of the low NOx combustion apparatus.

In FIG. 1 and FIG. 2, the lean burner 10 is configured such that a lean chamber 11 containing a lean air-fuel mixture is connected to a lean flame port 12, and a first air-fuel mixture chamber 13 is provided on both sides of the lean burner 10. The first burner 15 connected to the first flame port 14
Are provided in close contact with each other. Outside the first burner 15, a second burner 18 containing a second air-fuel mixture chamber 16 and connected to a second flame 17 is similarly provided in close contact with the lean burner 10 and the first burners 15 on both sides thereof. And the second burners 18 provided on both sides thereof are integrated to form a burner block 19.

A plurality of burner blocks 19 are housed in the burner case 20 and are connected to the combustion chamber 21. A fuel pipe 22 for supplying fuel and a fan 23 for supplying combustion air are provided upstream of the burner case 20. The fuel pipe 22 is provided with a lean mixer 25, a first mixer 26, and a second mixer 27, each of which is branched on a downstream side via a proportional valve 24. 28, a first fuel adjusting means 29, and a second fuel adjusting means 30. On the downstream side of the fan 23, a lean mixer 25, a first mixer 26, and a second mixer 27 are respectively provided in a branched manner, and each mixer is provided with a lean air adjusting means 31, One air adjusting means 32 and second air adjusting means 33 are interposed. And lean mixer 2
5 and the lean chamber 11 are connected by a lean passage 34, the first mixer 26 and the first air-fuel mixture chamber 13 are connected by a first passage 35, and the second mixer 27 and the second air-fuel mixture chamber 16 are connected by a second passage 36, respectively. Have been. Each passage is provided with branch passages 37, 37 ', 37 "for supplying each air-fuel mixture to the other burner block 19.
The first passage 35 and the second passage 36 are branched and connected to the two first mixture chambers 13 and the second mixture chamber 16, respectively.

The air supply system is provided with an air passage 39 connected to the burner case 20 via an air adjusting means 38 in addition to the connection with each mixer. The lean fuel adjustment means 28, the first fuel adjustment means 29, the second fuel adjustment means 30, the lean air adjustment means 31, the first air adjustment means 32, the second air adjustment means 33, and the air adjustment means 38 A configuration may be made by resistance setting means to adjust the flow distribution of each passage, or a means for switching according to the flow rate due to a change in the combustion amount by adding an electromagnetic valve or the like may be provided. The fan 23 and the proportional valve 24 are electrically connected to the control unit 40 and control so as to supply a required air amount and a fuel amount according to the variable amount of the combustion amount.

A plurality of temperature detecting means 41a, 41, such as thermocouples or thermistors, are provided above the lean flame port 12.
b, 41c, and the temperature detecting means 41a, 41b,
The output of 41c is connected to the control unit 40, and the control unit 40 changes the supply amount of the proportional valve 24 and the fan 23 according to this signal to increase or decrease the fuel supply amount or the combustion air supply amount.

Next, the operation and action will be described. The fuel supplied from the fuel pipe 22 is supplied to the fuel control means 28, the first fuel control means 29 and the second fuel control means 30 through the proportional valve 24 at a predetermined distribution ratio. After being adjusted to, the lean mixer 25,
It is supplied to the first mixer 26 and the second mixer 27, respectively. A part of the combustion air supplied from the fan 23 is adjusted as a secondary air to a predetermined flow rate by the air adjusting means 38, and then supplied to the burner case 20 through the air passage 39. Through the gap of combustion chamber 2
Spill into one. Most of the combustion air is branched into three and adjusted to a predetermined distribution ratio by the lean air adjusting means 31, the first air adjusting means 32, and the second air adjusting means 33, and then the lean mixer 25, the first mixing air. Are supplied to the mixer 26 and the second mixer 27, respectively. Most of the fuel is supplied to the lean fuel adjusting means 28.
Then, a large amount of combustion air is supplied to the lean mixer 25 by the lean air adjusting means 31, and becomes a uniform lean mixture. The lean burner 10 is provided in each burner block 19 through the lean passage 34 and the branch passage 37. Is supplied to the lean chamber 11.

The lean mixture supplied to the lean chamber 11 is shown in FIG.
As shown in FIG. 5, a lean flame E is ejected from the lean flame port 12 into the combustion chamber 21 and has a low flame temperature and an extremely low NOx concentration. Next, a small amount of fuel is supplied to the first fuel adjusting means 29,
An extremely small amount of combustion air is adjusted in flow rate by the first air adjusting means 32 and supplied to the first mixer 26 to become a uniform rich mixture, and passes through the first passage 35 and the branch passage 37 ′ to each burner block 19. Is supplied to the first air-fuel mixture chamber 13 provided at The rich mixture supplied to the first mixture chamber 13 flows out of the first flame port 14 into the combustion chamber 21 at a low speed and undergoes thermal decomposition to generate a large amount of active chemical species. At the base of the lean flame, a "high-temperature / high-reaction zone" α in which a combustion reaction is extremely active is formed, and an over-rich flame F that stabilizes a large amount of the lean flame at both bases is formed. Next, a very small amount of fuel is adjusted by the second fuel adjusting means 30 and a small amount of combustion air is adjusted by the second air adjusting means 33 and supplied to the second mixer 27 to form a uniform rich mixture to form a second rich air-fuel mixture. The mixture is supplied to the second mixture chamber 16 provided in each burner block 19 through the passage 36 and the branch path 37 ″. The rich mixture supplied to the second mixture chamber 16 is burned from the second flame port 17. It flows out into the chamber 21 at a low speed, forms a stable rich flame G, and ignites the rich mixture of the first burner 15 to generate a rich flame F,
At the same time, complete combustion is performed with the combustion air supplied from between the burner blocks 19.

As described above, the multi-concentration combustion having the three types of mixture concentration ignites the rich flame F with the stable rich flame G, which is provided even in the conventional lean-burn combustion.
A large amount of active reactive species, so-called radicals
Is diffused and supplied to the base of the gas to form a "high temperature / high reaction zone" α, which greatly promotes the stabilization of the lean flame. Here, the first fuel adjusting means 29 and the second fuel adjusting means 30 control the second flame opening 17.
By setting the fuel flow rate of the first flame port 16 to be larger than that of the first flame port 16 and making the fuel concentration of the first flame port 16 excessive, the generation amount of active chemical species increases and the “high temperature / high reaction zone” α Can be further increased, and the stability of the lean flame E can be further increased. As a result, the critical jet flow velocity from the lean flame port 12 from which the lean flame E blows could be greatly improved by promoting the stabilization of the base. Then, the flow rates of the respective air-fuel mixtures are controlled, and the flow rates of the lean air-fuel mixture, the first air-fuel mixture, and the second air-fuel mixture are increased and decreased at the same rate.

Thus, even when the amount of combustion is increased or decreased, the flow pattern of the light mixed gas ejected from the lean flame port 12 and that of the rich mixed gas ejected from the first flame port 14 are similar to each other, and the flow rate of the lean mixed gas is high. Since the concentration difference of the rich mixed gas is maintained, the substance diffusion from the rich mixed gas toward the lean mixed gas is stably maintained. For this reason, an intermediate product is supplied to the base of the lean flame outlet 12, and a “high temperature / high reaction zone” in which a combustion reaction is active is formed in a minute space of the base even if the amount of combustion increases or decreases. For this reason, the combustion ratio of the lean air-fuel mixture can be increased, and the concentration of the lean air-fuel mixture can be reduced to achieve ultra-low NOx.

As shown in FIG. 2, the lean flame E formed by being injected into the combustion chamber 21 from the lean flame port 12 occupying most of the combustion amount has a high air ratio, and therefore has a low flame temperature and extremely low NOx concentration. Although low, the burning rate decreases as the air ratio increases. For this reason, the lean flame E has a long flame length, and the flame length greatly increases and decreases depending on the air ratio. Therefore, a plurality of temperature detecting means 4 provided above the lean flame port 12
The air ratio in the lean flame E can be directly detected from the size of the lean burn flame E by 1a, 41b, 41c (three in the embodiment). These temperature detecting means 41a, 41b, 41c
Of the proportional valve 24 or the fan 23
, The fuel supply amount or the combustion air supply amount can be increased or decreased to always maintain the optimum combustion air ratio. Therefore, it is possible to further increase the combustion ratio of the lean air-fuel mixture, reduce the concentration of the lean air-fuel mixture, achieve ultra-low NOx, and secure a large variable width of the amount of combustion for maintaining good combustion.

FIG. 3 shows this lean flame E and the temperature detecting means 41.
The relationship between a, 41b, and 41c and the temperature is shown. The flame of the lean flame E having a large air ratio is generated at a place H where the combustion speed is balanced with that of the lean mixed gas ejected from the lean flame port 12, and the combustion is completed at a point J where the reaction is completed from I during the reaction. The temperature of the mixed gas gradually increases with the radiant heat of the flame from the lean flame port 12, but rises sharply with the heat of combustion from the point H where combustion starts. Then, the temperature rise ends at the point J where the combustion is completed, and thereafter, the temperature of the radiated heat is decreased. When the air ratio increases, the position H at which combustion starts shifts slightly to the upstream side, and the position J at which combustion is completed due to a decrease in combustion speed moves largely upstream. In addition, the temperature of J where this combustion is completed is
It decreases as the enthalpy increases. Therefore, the temperature detecting means 41
The air ratio can always be optimized according to the values of a, 41b and 41c.

Further, the temperature detecting means 41a, 41b, 41
By increasing or decreasing the fuel supply amount or the combustion air supply amount according to the mutual difference in the detected temperatures due to c, it is possible to detect the state of the flame and adjust the combustion air ratio. The combustion speed that determines the position of the flame is determined by the combustion air ratio. Therefore, a plurality of temperature detecting means 41a, 41b, 41
c, and the position of the flame can be determined from the difference between the outputs. In FIG. 3, the temperature in the flame is detected by the temperature detecting means 41b.
If it is set that the flame detection is detected by the temperature detecting means 41c, the difference between the outputs = the temperature detecting means 41c-the temperature detecting means 41b. It will be a plus. Further, the difference between the output of the temperature detecting means 41a near the combustion start location and the temperature in the flame = the difference between the outputs of the temperature detecting means 41b = the temperature detecting means 41b-the temperature detecting means 41a approximates the temperature rise of the flame and increases as the air ratio increases Become smaller. Therefore, the combustion air ratio can be adjusted optimally, and the ultra-low NO
x combustion can be realized.

(Embodiment 2) FIG. 4 is an overall sectional view showing a low NOx combustion apparatus according to Embodiment 2 of the present invention. A comparison control unit 43 connected to the temperature detection units 41a, 41b, and 41c is provided. The comparison control unit 43 stores a mutual target temperature difference value, and a temperature detection unit 41a, 41b, and 41c.
And a control unit 46 for increasing or decreasing the fuel supply amount or the combustion air supply amount in accordance with this value. This allows
A target temperature difference value corresponding to the optimum air ratio is stored in the storage unit 44 in advance, and this value and the temperature detection means 41a, 41b, 41c are stored.
The calculation and comparison unit 45 compares the mutual difference between the detected values with each other, and the control unit 46 increases or decreases the fuel supply amount or the combustion air supply amount according to this value, so that good combustion can always be maintained.

The temperature detecting means 41a, 41b, 41
When the amount of combustion is changed by increasing or decreasing the amount of fuel supply or the amount of combustion air supplied in accordance with the mutual ratio of the detected temperatures according to c, the combustion air ratio can be adjusted by detecting the state of the flame. As shown in FIG. 3, the injection speed of the mixed gas changes according to the increase or decrease of the combustion amount, and the place where the flame is generated and the place where the reaction is completed move. A plurality of temperature detecting means 41a, 41b, 41c are provided along the gas flow of the flame port, and the sensitivity of the flame is improved more than the mutual difference by the ratio of the outputs, so that the position of the flame can be clearly determined. That is, the temperature detecting means 41a, 41
The detected temperatures b and 41c have fluctuation factors such as a change in the amount of flame radiation with respect to the outside air temperature and the heat load. Therefore, by judging from the mutual ratio, this effect can be excluded and the detection sensitivity can be improved.

When the temperature in the flame is detected by the temperature detecting means 41b and the completion of the flame is detected by the temperature detecting means 41c, the ratio between the outputs is equal to the temperature detecting means 41c ÷ the temperature detecting means 41b, and the value becomes larger as the air ratio increases. Become. Further, the ratio between the output of the temperature detecting means 41a near the combustion start location and the temperature in the flame = the temperature detecting means 41b.
(4) The temperature detecting means 41a approximates the temperature rise of the flame and decreases as the air ratio increases. Therefore, the combustion air ratio can be optimally adjusted, the combustion air ratio can be optimally adjusted according to the change in the amount of combustion, and ultra-low NOx combustion can be realized.

FIG. 4 shows a plurality of temperature detecting means 41a, 41b,
41c is provided, the sensitivity of the output is improved more than the difference between the outputs, and the position of the flame can be clearly determined. Therefore, it is possible to optimally adjust the combustion air ratio according to the change in the combustion amount.
Is compared with the target temperature difference value corresponding to the optimum air ratio stored in the calculation unit 45, and the fuel supply amount or the combustion air supply amount is increased or decreased by the control unit 46 according to this value. Accordingly, good combustion can always be maintained, and even when the amount of combustion is small, the combustion ratio of the lean air-fuel mixture can be increased, and the concentration of the lean air-fuel mixture can be reduced to achieve ultra-low NOx.

(Embodiment 3) FIG. 5 is an overall sectional view showing a low NOx combustion apparatus according to Embodiment 3 of the present invention. A lean flame port 12 which communicates with the lean chamber 11 and supplies a lean mixture to flow out into the combustion chamber 21, and is provided near the lean flame port 12 which communicates with a first mixture chamber 13 adjacent to the lean chamber 11. First flame outlet 14
And a second flame port 17 provided in communication with a second gas mixture chamber 16 adjacent to the first gas mixture chamber 13 and provided in close proximity to the first flame port 14. In addition to making the concentration higher than that of the second mixture chamber 16, a plurality of flame detecting means 47a, 47b, 47c (three in this embodiment) are provided above the lean flame port 12.
Is provided. The flame detecting means 47a, 47b and 47c include a flame rod for detecting activated ions in the flame and a photoelectric tube for detecting the spectrum of the flame emission.

In this embodiment, a flame lot is used, and the flame detecting means 47a, 47b and 47c are connected to a ground wire 48 with the burner case 20 in which a rod is injected into the flame and metallically connected to the lean flame port 12 as ground. Configure the circuit. Therefore, a plurality of flame detecting means 47a, 47b, 4
7c, the air ratio in the lean flame can be directly detected from the lean combustion reaction.

The flame detecting means 47a, 47b,
By controlling the proportional valve 24 or the fan 23 by the control unit 40 with the output of 47c, the fuel supply amount or the combustion air supply amount can be increased or decreased to always maintain the optimum combustion air ratio.
Therefore, it is possible to further increase the combustion ratio of the lean air-fuel mixture, reduce the concentration of the lean air-fuel mixture, achieve ultra-low NOx, and secure a large variable width of the amount of combustion for maintaining good combustion.

FIG. 6 shows the shape of the lean flame due to the change in the air ratio, and FIG. 7 shows the lean flame and the flame detecting means 47a, 4b.
7 shows the relationship with the outputs of 7b and 47c. The flame of the lean flame E having a large air ratio is generated at a place H where the combustion speed is balanced with that of the lean mixed gas ejected from the lean flame port 12, and the combustion is completed at a point J where the reaction is completed from I during the reaction. The detection output by the flame rod detects the amount of current flowing between the electrodes due to the ionization of the radical intermediate produced by the combustion reaction in a state where a voltage is applied between the electrodes. Intermediate products due to combustion are generated at the point H where combustion starts, and the detection output sharply increases. Then, at the point J where the combustion is completed, the combustion reaction ends and the intermediate product disappears, and thereafter, the size decreases rapidly. When the air ratio increases, the position H at which combustion starts shifts slightly to the upstream side, and the position J at which combustion is completed due to a decrease in combustion speed moves largely upstream. Also, as the air ratio increases, the concentration of the intermediate product decreases, and the overall value decreases. Therefore, the air ratio can always be optimized according to the values of the temperature detecting means 41a, 41b, 41c. In addition, since the flame rod directly processes the state of the flame with an electric signal, the air ratio can be directly detected from the lean burn state with a quick response. Since the fuel supply amount or the combustion air supply amount is increased or decreased by the output of the flame detection means, the optimum combustion air ratio can always be maintained with good responsiveness. For this reason, the combustion ratio of the lean air-fuel mixture is increased, and the concentration of the lean air-fuel mixture is reduced to reduce the ultra-low NO.
x can be achieved, and also when the combustion amount is changed, a large variable width of the combustion amount that maintains good combustion can be secured.

The flame detecting means 47a, 47b, 47
By increasing or decreasing the fuel supply amount or the combustion air supply amount according to the mutual difference in the output due to c, the flame state can be detected quickly and the combustion air ratio can be adjusted. The lean flame having a large air ratio generates a flame when the combustion speed is balanced with the mixed gas ejected from the lean flame port 12, and the combustion is completed when the reaction is completed. The combustion speed that determines the position of the flame is determined by the combustion air ratio. A plurality of flame detecting means 47a, 47b, 47c are provided along the gas flow of the lean flame port 12, and the position of the flame can be quickly determined by the difference between the outputs. In FIG. 7, if it is set that the flame detection means 47b detects the completion of the flame and the flame detection means 47c detects the completion of the flame, the difference between the outputs = flame detection means 47c-flame detection means 47b, the air ratio is smaller than normal. In this case, the value is negative, and when the air ratio is large, the value is positive. Further, the difference between the output of the flame detecting means 47a near the combustion start location and the output of the flame detecting means 47b during the flame = flame detecting means 47b-the flame detecting means 47a approximates the intermediate concentration of the flame and increases as the air ratio increases. growing. Therefore, the responsiveness can be adjusted quickly and the combustion air ratio can be optimally adjusted, and ultra-low NOx combustion can be realized.

Also, in the third embodiment, a comparison control unit 43 connected to the flame detection means 47a, 47b, 47c is provided. The comparison control unit 43 includes a storage unit 44 for storing a mutual target temperature difference value, and a flame control unit. Detection means 47a, 47b, 47
an operation comparing unit 45 for comparing the detected value of c with the mutual difference,
The control unit 46 increases or decreases the fuel supply amount or the combustion air supply amount according to this value. Thereby, the target temperature difference value corresponding to the optimum air ratio is stored in the storage unit 4 in advance.
4 and this value and the flame detection means 47a, 47b, 4
7c are compared with each other by the operation comparing unit 45, and the fuel supply amount or the combustion air supply amount is increased or decreased by the control unit 46 in accordance with this value, so that quick response and good combustion are always achieved. Can be maintained. Therefore, it is possible to adjust the combustion air ratio optimally with a quick response in response to a change in the combustion amount, and to realize ultra-low NOx combustion.

The flame detecting means 47a, 47b, 47
Even when the amount of combustion is changed by increasing or decreasing the amount of fuel supply or the amount of combustion air supply in accordance with the mutual ratio of the detection outputs by c, the flame air state can be detected quickly and the combustion air ratio can be adjusted. As shown in FIG. 7, the injection speed of the mixed gas changes according to the increase and decrease of the combustion amount, and the place where the flame is generated and the place where the reaction is completed move. A plurality of flame detecting means 47a, 47b, 47c are provided along the gas flow of the lean flame port 12,
Due to the ratio between the outputs, the sensitivity is improved more than the difference between the outputs, and the position of the flame can be clearly determined. That is, the flame detection outputs of the flame detection means 47a, 47b, and 47c include fluctuation elements such as a change in insulation resistance due to combustion heat and a disturbance component such as noise. Therefore, by judging from the mutual ratio, this effect can be excluded and the detection sensitivity can be improved. The flame is detected by the flame detecting means 47b, and the completion of the flame is detected by the temperature detecting means 4b.
7c, the output ratio = flame detecting means 47c
と な り It becomes the flame detecting means 47b, and becomes small when the air ratio is small, and has a small value when the air ratio is large. Further, the ratio of the mutual output of the flame detecting means 47a near the combustion start location and the output of the flame detecting means 47b in the flame = flame detecting means 47b 手段 the flame detecting means 47a approximates the concentration of the intermediate product due to the combustion reaction of the flame. It decreases as the ratio increases. Therefore, the combustion air ratio can be optimally adjusted, the combustion air ratio can be optimally adjusted with a quick response in response to a change in the combustion amount, and ultra-low NOx combustion can be realized. .

FIG. 5 shows a flame detecting means 4.
7a, 47b, and 47c are connected to each other, and the comparison control unit 43 includes a storage unit 44 for storing a mutual target output ratio value, and flame detection units 47a, 47b, and 47.
calculation comparing section 45 for comparing the detected value of c with the mutual ratio value
And a control unit 46 for increasing or decreasing the fuel supply amount or the combustion air supply amount according to this value, so that a plurality of flame detection means 47a, 47b, 47c, the sensitivity of the output is improved more than the difference between the outputs, the response is quick, and the position of the flame can be clearly identified. For that reason,
The combustion air ratio can be optimally adjusted in response to the change in the combustion amount. Further, the target output difference value corresponding to the optimal air ratio stored in the storage unit 44 is compared with the operation comparison unit 45, and this value is compared. By controlling the control unit 46 to increase or decrease the fuel supply amount or the combustion air supply amount in accordance with the change in the combustion amount, it is possible to always maintain good combustion in accordance with the change in the combustion amount. In this case, the combustion ratio of the lean air-fuel mixture is increased, and the concentration of the lean air-fuel mixture is reduced to reduce ultra-low NOx.
Can be achieved.

In the configuration shown in the first to third embodiments, the storage unit 44 stores a value obtained by increasing or decreasing the fuel supply amount or the combustion air supply amount in comparison with the value detected by the temperature detecting means or the flame detecting means during combustion. And the next combustion is started with this value. This allows the proportional valve 24 and the fan 2
Even when the performance changes due to deterioration over time, such as 3, the air-fuel ratio can start combustion in an optimal state, ensuring the ignition and suppressing the generation of unburned components, improving the performance and prolonging the time. Performance changes due to wear deformation due to use can be corrected, and reliability can be ensured durably.

In addition, the combustion amount and the air amount are set to be constant for a certain time from the start of combustion, whereby the air ratio of the flame at the time of ignition can be detected more accurately. Since the temperature of the flame at the time of ignition rises rapidly and the combustion reaction is not equilibrium, it is difficult to discriminate between a change in the air ratio and a change in the combustion amount.
However, the influence of the air ratio can be detected by fixing the amount of combustion and the amount of air to a certain amount for a certain time. For this reason, the generation of unburned components can be further suppressed.

[0053]

As described above, according to the first aspect of the present invention,
The low NOx combustion device according to the present invention is characterized in that a lean flame port which communicates with the lean chamber and supplies the lean air mixture to the combustion chamber, and which communicates with the first air chamber adjacent to the lean chamber and is close to the lean flame port. A first flame port provided, and a second flame port provided in close proximity to the first flame port in communication with a second gas mixture chamber adjacent to the first gas mixture chamber; The concentration of the air chamber is made higher than the concentration of the second mixture chamber, and a plurality of temperature detecting means are provided above the lean flame port, and the fuel supply amount or the combustion air supply amount is increased or decreased by the temperature detecting means. With this configuration, the optimum combustion air ratio can be always maintained. For this reason, the combustion ratio of the lean air-fuel mixture can be increased, and the concentration of the lean air-fuel mixture can be reduced to achieve ultra-low NOx.

The low NOx combustion apparatus according to the second aspect of the present invention detects the state of the flame by increasing or decreasing the fuel supply amount or the combustion air supply amount according to the difference between the temperatures detected by the temperature detecting means. The combustion air ratio can be adjusted. Further, since a plurality of temperature detecting means are provided and the position of the flame can be determined based on the difference between the outputs, the combustion air ratio can be adjusted optimally, and ultra-low NOx combustion can be realized.

According to a third aspect of the present invention, the low NOx combustion apparatus comprises a storage section, an operation comparison section, and a control section, and stores in advance a target temperature difference value corresponding to an optimum air ratio in the storage section. This value is compared with the mutual difference between the values detected by the temperature detection means in the arithmetic and comparison unit, and the control unit increases or decreases the fuel supply amount or the combustion air supply amount in accordance with this value, thereby always achieving good combustion. Can be maintained.

In the low NOx combustion apparatus according to the fourth aspect of the present invention, when the amount of combustion is changed by increasing or decreasing the amount of fuel supply or the amount of combustion air supplied in accordance with the mutual ratio of the temperatures detected by the temperature detecting means. Also, the combustion air ratio can be adjusted by detecting the state of the flame, and the sensitivity of the output can be improved more than the difference between the outputs, so that the position of the flame can be clearly determined. Therefore, the combustion air ratio can be optimally adjusted according to the change in the combustion amount, and ultra-low NOx combustion can be realized.

In the low NOx combustion apparatus according to the fifth aspect of the present invention, the sensitivity is improved as compared with the difference between the outputs of the temperature detecting means due to the ratio of the outputs of the temperature detecting means due to the configuration comprising the storage section, the operation comparing section and the control section. The position of the flame can be clearly determined. Therefore, it is possible to optimally adjust the combustion air ratio in accordance with the change in the amount of combustion, and further, it is possible to always maintain good combustion in accordance with the change in the amount of combustion, and to use a lean air-fuel mixture even when the amount of combustion is small. And the concentration of the lean mixture can be reduced to achieve ultra-low NOx.

In the low NOx combustion apparatus according to the sixth aspect of the present invention, since a plurality of flame detecting means are provided above the lean flame port, the air ratio can be directly detected with a quick response from the lean combustion state. Since the fuel supply amount or the combustion air supply amount is increased or decreased according to the output of the detection means, the optimum combustion air ratio can always be maintained with good responsiveness. For this reason, the combustion ratio of the lean air-fuel mixture can be increased, and the concentration of the lean air-fuel mixture can be reduced to achieve ultra-low NOx. A large width can be secured.

The low NOx combustion apparatus according to claim 7 of the present invention can increase or decrease the fuel supply amount or the combustion air supply amount according to the mutual difference between the outputs from the flame detecting means. From the difference between the outputs, the position of the flame can be determined with high responsiveness. Therefore, the combustion air ratio can be optimally adjusted instantaneously, and ultra-low NOx combustion can be realized.

The low NOx combustion apparatus according to claim 8 of the present invention comprises a storage section, an operation comparison section, and a control section, so that the target output difference value and the detection value from the flame detection means having a quick response can be obtained. By comparing the difference with the calculation comparison unit and increasing / decreasing the difference by the control unit, the responsiveness is quick and good combustion can always be maintained.

In the low NOx combustion apparatus according to the ninth aspect of the present invention, the fuel supply amount or the combustion air supply amount can be increased or decreased according to the mutual ratio of the outputs from the flame detecting means.
Depending on the ratio of the outputs of the flame detecting means, the sensitivity is improved as compared with the mutual difference, so that the position of the flame can be clearly identified and the response can be determined quickly. Therefore, it is possible to quickly and optimally adjust the combustion air ratio in response to a change in the combustion amount, and to achieve an extremely low NOx.
Combustion can be realized.

In the low NOx combustion apparatus according to the tenth aspect of the present invention, the sensitivity is improved more than the mutual difference by the ratio of the outputs of the flame detecting means by the configuration including the storage section, the operation comparing section and the control section. The responsiveness is fast and the position of the flame can be clearly identified. Therefore, it is possible to quickly and optimally adjust the combustion air ratio in response to a change in the amount of combustion, and furthermore, a target output difference value corresponding to the optimal air ratio stored in the storage unit and a calculation comparison unit. By comparing and increasing / decreasing the fuel supply amount or the combustion air supply amount in accordance with this value by the control unit, it is possible to always maintain good combustion in response to a rapid response change in the combustion amount, and to control the combustion amount in accordance with the load. Even during the increase / decrease or when the combustion amount is small, the combustion ratio of the lean air-fuel mixture can be increased, and the concentration of the lean air-fuel mixture can be reduced to achieve ultra-low NOx.

A low NOx combustion apparatus according to claim 11 of the present invention has a configuration in which a value obtained by increasing or decreasing a supply amount is stored in a storage unit, compared with a detection value of a detection means, and the next combustion is started with this value. As a result, the reliability of ignition and the generation of unburned components can be suppressed, and the performance can be improved, and performance changes due to wear deformation due to long-term use can be corrected, and durability can be ensured in reliability.

The low NOx combustion apparatus according to the twelfth aspect of the present invention has a structure in which the combustion amount and the air amount are constant for a certain period of time from the start of combustion, so that the air ratio of the flame at the time of ignition can be detected more accurately. And the generation of unburned components can be suppressed.

[Brief description of the drawings]

FIG. 1 is an overall sectional view of a combustion apparatus according to a first embodiment of the present invention.

FIG. 2 is a partially enlarged view of a main part of the combustion device.

FIG. 3 is an explanatory diagram of a position and a temperature of a temperature detecting unit according to the first embodiment.

FIG. 4 is an overall sectional view of a combustion apparatus according to a second embodiment of the present invention.

FIG. 5 is an overall sectional view of a combustion apparatus according to a third embodiment of the present invention.

FIG. 6 is a partially enlarged view of a main part of the combustion device.

FIG. 7 is an explanatory diagram of a position and an output of a flame detecting unit in Embodiments 2 and 3 of the present invention.

FIG. 8 is a partial sectional view of a conventional combustion device.

FIG. 9 is a partial cross-sectional view of another conventional combustion device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Lean chamber 12 Lean flame 13 First mixture chamber 14 First flame 16 Second mixture chamber 17 Second flame 23 Fan 24 Proportional valves 41a, 41b, 41c, temperature detection means 47a, 47b, 47c, flame Detection means

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F23N 5/10 310 F23N 5/10 310E 5/12 5/12 J 5/14 5/14 B 5/20 5/20 FF term (reference) 3K003 FA01 FB04 FB05 GA03 3K005 AA06 AB04 AC02 AC05 BA05 BA06 EA02 FA03 GA15 GB01 HA00 JA02 3K017 AA01 AA03 AA06 AB01 AB07 AD02 3K065 TA01 TA04 TA12 TB02 TB12 TD01 TE01 TF03 TH03 TN03

Claims (12)

[Claims] 1. A lean flame port communicating with a lean chamber and supplying and supplying a lean air-fuel mixture into a combustion chamber, and being provided in close proximity to the lean flame port and communicating with a first air-fuel mixture chamber adjacent to the lean chamber. A first flame port, having a second flame port provided in close proximity to the first flame port and communicating with a second gas mixture chamber adjacent to the first gas mixture chamber; A low NOx combustion in which the concentration is made higher than the concentration of the second mixture chamber and a plurality of temperature detecting means are provided above the lean flame port, and the temperature detecting means increases or decreases the fuel supply amount or the combustion air supply amount. apparatus. 2. The low NOx combustion apparatus according to claim 1, wherein the fuel supply amount or the combustion air supply amount is increased or decreased according to the mutual difference between the temperatures detected by the temperature detecting means. 3. A comparison control unit connected to the temperature detection unit, wherein the comparison control unit stores a mutual target temperature difference value and an operation for comparing the storage unit with the mutual difference between the values detected by the temperature detection unit. 2. The low NOx combustion apparatus according to claim 1, comprising: a comparison unit; and a control unit that increases or decreases a fuel supply amount or a combustion air supply amount according to the value. 4. The low NOx combustion apparatus according to claim 1, wherein the fuel supply amount or the combustion air supply amount is increased or decreased according to the mutual ratio of the temperatures detected by the temperature detecting means. 5. A comparison control unit connected to a temperature detection means, wherein the comparison control unit compares a storage unit storing mutual target temperature ratio values with a mutual ratio value of the values detected by the temperature detection unit. 2. The low NOx combustion apparatus according to claim 1, comprising: an arithmetic comparison unit; and a control unit that increases or decreases a fuel supply amount or a combustion air supply amount according to the value. 6. A lean flame port which communicates with the lean chamber and supplies and supplies a lean mixture into and from the combustion chamber, and is provided adjacent to the lean flame port which communicates with a first mixture chamber adjacent to the lean chamber. A first flame port, having a second flame port provided in close proximity to the first flame port and communicating with a second gas mixture chamber adjacent to the first gas mixture chamber; A low NOx combustion in which the concentration is made higher than that of the second mixture chamber and a plurality of flame detecting means are provided above the lean flame port, and the flame detecting means increases or decreases a fuel supply amount or a combustion air supply amount. apparatus. 7. The low NOx combustion apparatus according to claim 6, wherein the fuel supply amount or the combustion air supply amount is increased or decreased according to the mutual difference between the outputs of the flame detecting means. 8. A comparison control unit connected to the flame detection means is provided, the comparison control unit storing a mutual target output difference value, and an arithmetic operation for comparing the difference between the values detected by the flame detection means. 7. The low NOx combustion apparatus according to claim 6, comprising a comparison unit and a control unit that increases or decreases the fuel supply amount or the combustion air supply amount according to the value. 9. The low NOx combustion apparatus according to claim 6, wherein a fuel supply amount or a combustion air supply amount is increased or decreased in accordance with a mutual ratio of outputs from the flame detection means. 10. A comparison control unit connected to the flame detection means, wherein the comparison control part compares a storage unit for storing mutual target output ratio values with a mutual ratio value of the values detected by the flame detection means. 7. The low NOx combustion apparatus according to claim 6, comprising: an operation comparison unit; and a control unit that increases or decreases the fuel supply amount or the combustion air supply amount according to the value. 11. A value obtained by comparing a value detected by a temperature detecting means or a flame detecting means during combustion with a fuel supply amount or a combustion air supply amount is stored in a storage unit, and the next combustion is performed by using this value. Low NO according to claims 3, 5, 8, 10 starting
x combustion device. 12. The low NOx combustion apparatus according to claim 1, wherein the amount of combustion and the amount of air are constant for a certain period from the start of combustion.