JPH0949629A - Combustor control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the smell at the time of extinguishing by a method wherein a half cycle of the corrugation of an AC power source voltage is counted, and a voltage of 1/n to output 1 cycle only among (n) cycles being counted at the time of extinguishing, is applied to a blower for combustion, and braking is applied. SOLUTION: When a power source switch is turned off, and an extinguishing motion is performed, the applying of a voltage to a fuel pump 21 is stopped. In the meantime, regarding combustion air, at every zero-cross pulse being output from a zero-cross pulse generating circuit 28, a counter in a signal generating means 29 is added. Then, it is repeated until the value of the counter becomes a specified value (n), and when the counter value becomes the specified value (n), the counter is cleared to zero, and Hi signal is output from the signal generating means 29, a voltage of 1/n is applied to a combustion blower 24. Then, when the extinguishing process is completed, Lo signal is output from the signal generating means 29, and the combustion blower is placed under a stopped state. In this case, if the specified value (n) is made 2, the corrugation becomes the same corrugation as when a half-wave rectification is performed, and the reduction speed of the combustion air is fastest, and if the value of the specified value (n) is made larger on the contrary, the reduction speed becomes slower.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a combustor controller for premixing vaporized liquid fuel and combustion air for combustion.

[0002]

2. Description of the Related Art FIG. 10 shows, for example, JP-A-5-149514.
FIG. 7 is a cross-sectional view of a combustor of the conventional liquid fuel combustion device shown in Japanese Patent Publication No. In the figure, 1 is a vaporizer that forms a vaporization chamber for vaporizing liquid fuel, and 2 is an electric heater that is embedded in the side wall of the vaporizer 1 and heats the vaporizer 1. Reference numeral 3 is a throttle portion fitted and fixed to the upper portion of the vaporizer 1, 4 is a burner head provided on the upper portion of the throttle portion 3, and 5 is a plurality of flame holes provided on the side wall of the burner head 4. 6 is a wire net tightly wound around the outer peripheral surface of the burner head 4, 7 is a cap placed on the upper part of the wire net, 8
Is a special screw whose one end is embedded in the throttle portion 3 for fixing the burner head 4 and the cap 7 to the throttle portion 3.

Reference numeral 9 is a mixing plate provided in the burner head 4 and having a plurality of holes on the bottom surface. The mixing plate 9 rectifies the vaporized liquid fuel and then ejects it from the plurality of flame holes 5. . Reference numeral 10 denotes an annular flame holding ring attached to the upper portion of the vaporizer 1 so as to surround the burner head 4.

Reference numeral 11 denotes a nozzle installed on the side wall of the carburetor 1 and opening in the carburetor 1. The nozzle 11 is an air supply pipe (not shown) communicating with a combustion blower (not shown). It is connected to the. Further, the nozzle 11 includes an inlet portion 11a, a tapered portion 11b and a throat portion 11c. Reference numeral 12 is a fuel supply pipe arranged coaxially with the nozzle 11 so that the combustion supply port 12a at the tip end projects from the throat portion 11c. The liquid fuel in the fuel tank (not shown) is the fuel supply pipe. It is designed to be supplied to the carburetor 1 via a fuel pump (not shown) via 12.

Next, the operation will be described. Electric heater 2
By energizing the vaporizer 1, the vaporizer 1 is preheated to a temperature (200 to 300 ° C.) necessary for vaporizing the liquid fuel. After completion of preheating, the combustion air sent from the combustion blower to the air supply pipe is supplied from the nozzle 11 to the carburetor 1. Further, from the fuel supply pipe 12, an amount of liquid fuel having a primary air ratio (= supply air amount / theoretical air amount) of about 0.8 is supplied to the carburetor 1.

The supplied liquid fuel is atomized by the flow of combustion air and vaporized on the preheated vaporization surface. The vaporized liquid fuel is further premixed with the combustion air when passing through the throttle portion 3 to have a uniform concentration distribution. After that, the premixed mixture of the liquid fuel and the combustion air is rectified by passing through a plurality of holes in the bottom surface of the mixing plate 9, and the side wall of the mixing plate 9 effects the vertical flow velocity distribution of the burner head 4. Becomes uniform. The premixed gas is ignited on the flame holes 5 of the burner head 4 by an igniter (not shown) to form a primary flame 13 and a secondary flame 14. After the start of combustion, the carburetor 1 is heated by the heat recovery from the flame by the flame holding ring 10 and the like, so that the input to the electric heater 2 is not necessary.

By the way, at the time of extinguishing such a combustion apparatus, the application of the voltage to the fuel pump and the combustion blower was simultaneously released. In this case, the fuel pump stops almost instantaneously, whereas the combustion blower gradually decreases the rotation speed due to its inertia even after the application of the voltage is stopped, and stops after a few seconds. Therefore, the amount of fuel decreases rapidly as shown by the solid line in FIG. 11, and when the fuel pump is de-energized at T ₀ , the evaporation amount becomes zero at T ₁ .

On the other hand, the reduction of the combustion air is slower than that of the fuel, and the supply is stopped at T ₂ as indicated by the broken line. In this type of combustor, the combustion continues because the ratio of the combustion air to the fuel (primary air ratio) is in the combustible range from T ₀ to T when extinguishing the fire, but the air becomes excessive after T. As a result, the flame blows off. As described above, due to the imbalance between the decreasing speeds of the both, the primary air ratio at the time of extinguishing increases instantaneously and the flame is blown out, so the unburned fuel in the shaded area in FIG. 11 is discharged into the room. At this time, a part of the unburned fuel comes into contact with the high temperature part of the combustion apparatus and is partially oxidized, and substances such as aldehyde are produced, which causes an unpleasant odor accompanied by irritation.

As a measure for reducing the odor of fire extinguishing, there has been considered a control device for the combustor which does not make the structure of the combustor complicated and emits little odor when extinguishing the fire. For example, JP-A-6
The combustion operation shown in Japanese Patent Laid-Open No. 94235 is basically the same as that of the combustion apparatus shown in FIG. 10. Combustion air from a combustion blower (not shown) and fuel supply means (not shown). The fuel from is vaporized and mixed in the vaporization chamber 1 and burned in the burner head 4. When the user turns off the power switch (not shown) to extinguish the fire when extinguishing the fire, the application of voltage to the fuel pump (not shown) is stopped. In this case, the method of stopping the fuel pump is the same as in FIG. 11,
As shown by the solid line in FIG. 12, the decrease in fuel becomes zero from the time T ₀ to T ₁ , which is the same decrease rate as in FIG. 11.

On the other hand, as for the combustion air, the combustion blower (not shown) is switched in its drive circuit to perform half-wave rectification or full-wave rectification of the AC power supply voltage as shown in FIG. Brake (not shown) to reduce air flow. At this time, the flow rate of the combustion air is as shown in FIG.
As shown in FIG. 11, it becomes zero in a short time as compared with FIG.
Therefore, the combustion air becomes approximately the same as the fuel reduction rate, so that the combustion amount decreases while the ratio of the combustion air to the fuel (primary air ratio) remains constant. Then, as the combustion amount becomes smaller, the primary flame 13 approaches the burner head, so the primary flame 13 is cooled by the burner head 4, and when the cooling amount exceeds the combustion amount (time T in FIG. 12), the flame becomes Extinguish the flame. The unburned fuel in this case is the portion indicated by the diagonal lines in FIG. 12, and is smaller than that in FIG.

[0011]

Since the conventional control device for the combustor is configured as described above, it is almost constant when the AC blower for combustion is half-wave rectified and the combustion blower is braked when the fire is extinguished. Therefore, the reduction speed of the combustion air is fixed. However, in the actual combustion control, the rate of decrease of fuel varies greatly depending on the amount of combustion and the structure of the combustor, such as the vaporization delay during fire extinguishing and the time delay from the vaporization chamber to the flame holes. is not. As a result, there is a problem that it is difficult to reduce the combustion amount and extinguish the fire by keeping the ratio (primary air ratio) constant, that is, the rate of decrease of the combustion air and the fuel is almost the same.

Also, when the combustion blower is rotating at a low speed, the inertial force is small, so the time until the air flow rate becomes zero becomes short. Further, the low-speed rotation region is often used with weak combustion, and the delay in vaporization tends to be remarkable during weak combustion. For example, in the conventional combustor, the reduction rate of combustion air becomes faster than that of fuel. As shown in, the same effect is obtained by delaying the combustion air reduction start time T ₀₁ , but similarly, the ratio of the combustion air and the fuel at the start of the supply amount reduction collapses (the fuel concentration decreases), There is a problem that the deodorizing effect is weakened.

On the contrary, when the combustion air decreases more slowly than the fuel, as shown in FIG. 15, the combustion air decrease start time T ₀₂ is delayed so that the air-fuel mixture is extinguishing (T _{0 to} T ₂ ). The same effect was obtained by keeping the fuel concentration in the flammable range, but the ratio of combustion air and fuel at the start of the supply decrease collapses (the combustion concentration increases), and the deodorizing effect diminishes.
There is a problem that the red fire may easily extinguish the fire and cause the user to feel distrust.

Furthermore, when the AC power supply voltage is half-wave rectified and the combustion blower is braked when the fire is extinguished, a sudden braking force is applied, which causes noise (abnormal stop sound).

The present invention has been made to solve the above-mentioned problems, and is a control device for a combustor having a wide combustion range and various vaporization characteristics, with less odor emitted during extinction. Aim to get.

[0016]

A combustor control apparatus according to the present invention includes a vaporizer for vaporizing a liquid fuel, a fuel supply means for supplying the liquid fuel to the vaporizer, a vaporized liquid fuel for combustion. A flame hole for burning a premixed air, a blower for combustion for supplying combustion air, a control circuit for controlling the blower for combustion and the fuel supply means, and an AC power supply voltage of zero volt in the control circuit. A zero-cross pulse generation circuit that generates a pulse at an intersecting point, a signal generation unit that outputs an oscillation output signal based on the pulse generated by the zero-cross pulse generation circuit, and between the combustion blower and the AC power supply voltage. A thyristor inserted and connected,
The thyristor is provided with an ignition circuit that ignites based on the oscillation output signal output from the signal generating means, and at the time of fire extinguishing, the liquid flow rate is reduced and the combustion blower is braked to reduce the air flow rate to extinguish the fire. In a control device for a combustor configured to keep the concentration of a premixed gas in operation within a combustible range, a counter for counting a half cycle of the waveform of the AC power supply voltage is provided in the signal generating means, and the signal generating means is Of the n cycles counted by the counter when extinguishing the fire, a voltage of 1 / n that outputs only one cycle is applied to the combustion blower to apply a brake.

Further, the control device for a combustor according to the present invention includes a vaporizer for vaporizing liquid fuel, fuel supply means for supplying the liquid fuel to the vaporizer, and premixing of the vaporized liquid fuel and combustion air. A flame hole that burns air, a combustion blower that supplies combustion air, a control circuit that controls the combustion blower and the fuel supply means, and a point where the AC power supply voltage crosses zero volts in this control circuit. A zero-cross pulse generation circuit that generates a pulse, a signal generation unit that outputs an oscillation output signal based on the pulse generated by the zero-cross pulse generation circuit, and is inserted and connected between the combustion blower and the AC power supply voltage. A thyristor and an ignition circuit for igniting the thyristor based on an oscillation output signal output from the signal generating means are provided, and when the fire is extinguished, the liquid fuel is reduced and burned. In a control device for a combustor, in which a blower is braked to reduce the air flow rate and the concentration of the premixed air mixture during the fire extinguishing operation is kept in a combustible range, a half of the waveform of the AC power supply voltage is generated in the signal generating means. A counter for counting cycles is provided, and the signal generating means alternately applies a 1 / n voltage and a 1 / m voltage to the combustion blower for outputting only one cycle out of n cycles or m cycles counted by the counter. The brakes are then applied.

Further, in the above-described control device for a combustor according to the present invention, the combustion blower is decelerated for a certain period from the start of extinguishing, and then the voltage of 1 / n or 1 / n is applied. The 1 / m voltage is alternately applied to stop.

In addition, the control device for a combustor according to the present invention is the above-mentioned one, in which a 1 / n voltage or 1 / n voltage and 1 / m voltage are alternately applied to the combustion blower for a certain period from the start of extinction. It is configured to apply the voltage to decelerate, and then to stop by inertia.

Further, the control device for a combustor according to the present invention is a fuel supply means for supplying a liquid fuel, a combustion blower for supplying combustion air, and a control for controlling the combustion blower and the fuel supply means. A circuit, a vaporizer for vaporizing the liquid fuel supplied by the fuel supply means, and a flame hole for burning a premixed mixture of the liquid fuel vaporized by the vaporizer and combustion air, and at the time of a fire extinguishing operation, The control circuit controls the rotation speed of the combustion blower so as to keep the concentration of the premixed air within the combustible range, and stops the combustion blower.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 FIG. An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing a control device for a combustor according to the present invention. The same or corresponding parts as those of the conventional example shown in FIG. 10 are designated by the same reference numerals, and the description thereof will be omitted.

In FIG. 1, reference numeral 21 is a fuel pump (fuel supply means) used in the conventional example for supplying liquid fuel. One end of this fuel pump is located in a fuel tank 22 and the other end is a fuel supply pipe. It is connected to 12. Also, 2
Reference numeral 3 is an air supply pipe (combustion air supply path) which is connected to the nozzle 11 and supplies combustion air, and 24 is a combustion blower. Reference numeral 25 is a control circuit for controlling the fuel pump 21 and the combustion blower 24. Reference numeral 26 is an AC power supply voltage, and 27 is an insulating transformer, the primary side of which is connected to the AC power supply voltage 26.

Reference numeral 28 is a zero-cross pulse generating circuit connected to the secondary side of the insulating transformer 27 and generating a pulse at a point where the AC power supply voltage 26 crosses zero volt. 29 is a pulse generated by the zero-cross pulse generating circuit 28. Signal generating means for outputting an oscillation output signal based on the above, and is provided in the microcomputer 30. Reference numeral 31 is an ignition circuit for igniting a thyristor 32 inserted and connected between the combustion blower 24 and the AC power supply voltage 26 based on the oscillation output signal output from the signal generating means 29. 3
A pump drive circuit 3 drives the fuel pump 21 based on a drive signal from the microcomputer 30.

Next, the ignition operation will be described. The operation of starting combustion (ignition) is almost the same as the conventional example. Vaporizer 1
Is heated to a predetermined temperature (200-300 ° C),
The combustion blower 24 rotates and the amount of air required for combustion is supplied to the carburetor 1. After operating the ignition device (not shown), the fuel pump 21 starts supplying the liquid fuel. The liquid fuel ejected into the vaporizer 1 is vaporized on the vaporization surface and mixed with combustion air to form a premixed gas. The premixed air passes through the throttle portion 3 and the mixing plate 9 and is ignited on the flame holes 5 of the burner head 4 to form the primary flame 13 and the secondary flame 14. The burned gas is mixed with air from a convection fan (not shown) and used for heating the room.

FIG. 2 is a flow chart showing the operation of the first embodiment of the present invention having the above construction. After the ignition operation, combustion is started (step 50). During combustion, the microcomputer 30 determines the combustion amount based on the difference between the set temperature and the room temperature, and supplies a predetermined signal to the pump drive circuit 33 to supply the fuel corresponding to the combustion amount to the carburetor 1. It outputs and drives the fuel pump 21.

On the other hand, in order to maintain the concentration of the premixed gas at a constant level, and supply the combustion air corresponding to this fuel to the carburetor 1, the combustion blower 24 has a microcomputer 30.
It is controlled so that the number of rotations is stored in advance (step 51). Power switch (not shown)
When the fire extinguishing operation is performed by turning OFF, the fire extinguishing process is performed (step 52), the application of the voltage to the fuel pump 21 is stopped by the microcomputer 30, and the fuel supply is stopped (step 53).

On the other hand, for the combustion air, the counter provided in the signal generating means 29 is incremented for each zero-cross pulse (b in FIG. 3) output from the zero-cross pulse generating circuit 28 (step 54). When the count value is smaller than the predetermined value n (step 55), the signal generator 29 outputs the Lo signal (step 5).
6) No voltage is applied to the combustion blower 24. Steps 54 to 56 are repeated until the counter value becomes n, and when the counter value becomes n, the counter is cleared to zero (step 57) and the Hi signal is output from the signal generating means 29 (step 58), and the blower for combustion is used. A voltage is applied to 24.

By repeating the above processing, a voltage of 1 / n is applied to the combustion blower (d in FIG. 3). After that, when the fire extinguishing process ends, the Lo signal is output from the signal generating means 29 (step 59), and the combustion blower 24 is stopped. Here, when the value of the predetermined value n is set to 2, the waveform becomes the same as in the case of the conventional half-wave rectification, and the reduction speed of the combustion air becomes the fastest. On the contrary, as the value of the predetermined value n is increased, the decreasing speed becomes slower.

Here, if n becomes too large, FIG.
It becomes the same as the decreasing speed when stopping by inertia like the broken line of. Thus, by determining the predetermined value n according to the combustion amount immediately before extinguishing and the vaporization characteristics of the combustor, even in a combustor having a wide combustion range and various vaporization characteristics, Since the amount of unburned fuel can be extinguished by keeping the supply amount constant at the time of starting the supply amount reduction, it is possible to reduce the amount of unburned fuel and to obtain a control device for a combustor with less odor emitted during extinction.

Although the drive signal of the fuel pump 21 is pulse-controlled as shown in FIG. 4E, when the brake control of the combustion blower 24 is started based on the operation switch OFF signal of the user, the fuel is reduced. There is a maximum timing difference of one pulse period between the start and the start of the reduction of the combustion air. Especially, in the case of weak combustion, the interval of the cycle is long and the deviation becomes large. Therefore, the standard is not the OFF signal of the power switch,
One pulse of the pump drive signal is output after turning OFF (e in FIG. 4).
By using this pulse as a reference, it is possible to accurately match the timing when the supply amount of fuel and combustion air starts to decrease.

Embodiment 2 FIG. FIG. 5 is a flow chart showing the operation according to the second embodiment of the present invention. Note that FIG.
This applies to the output signal processing unit shown inside (60 in FIG. 2). When the fire extinguishing process is started, the counter provided in the signal generating means 29 is incremented for each zero-cross pulse (step 61). If the flag is 0 (step 62), the same operation as in the first embodiment is performed, and the combustion blower 24 is set to 1
/ N voltage is applied.

When the counter becomes n and the signal output is set to Hi (step 67), the flag is inverted (0 →
1) Do (step 66). Next, after the counter is added, the flag is 1, so the flag is processed by a predetermined value m (step 68), the voltage of 1 / m is applied to the combustion blower 24 in the same manner as in the above process, and the flag is inverted again. (1 →
0). After that, this process is repeated and an output signal as shown in c of FIG. 6 is oscillated, and a 1 / n voltage and a 1 / m voltage as shown in d of FIG. 6 are alternately applied to the combustion blower 24. become. As a result, the combustion blower 24 can be set more finely than the reduction speed of the combustion blower 24 shown in the first embodiment. Therefore, in the combustor having a wider combustion range and various vaporization characteristics, the mixture concentration at the time of the fire extinguishing operation is supplied. Since the amount of unburned fuel can be reduced and the amount of unburned fuel can be extinguished while keeping the amount constant from the start of the amount reduction, it is possible to obtain a control device for a combustor with less odor emitted during extinguishment.

Embodiment 3 FIG. FIG. 7 is an explanatory diagram showing how the fuel and the combustion air are reduced when the combustion of the combustor according to the third embodiment of the present invention is extinguished. At the time of extinguishing, in the case of a combustor or a combustion amount in which the rate of decrease of fuel changes as shown by the solid line in FIG. 7 due to vaporization delay, etc., decrease start T ₀ to T ₀₃
Until, the output to the inter-combustion blower 24 is stopped, and the combustion air supply amount is reduced by inertia. Then, at time T ₀₃ , the combustion blower 24 is braked to reduce the amount of air and T ₂ is made zero.

By operating in this way, even when the fuel decrease transition due to vaporization delay after extinguishing is not linear as in the conventional example, but is parabolic as shown by the solid line in FIG. 7,
Since the air-fuel mixture concentration during fire extinguishing operation can be kept constant from the start of the supply amount reduction to extinguish the fire, it is possible to reduce the unburned fuel and to obtain a control device for the combustor with less odor emitted during fire extinguishing. You can

Example 4. FIG. 8 is an explanatory view showing a state of reduction of fuel and combustion air at the time of extinguishing the fire of the combustor according to the fourth embodiment of the present invention. In the case of a combustor in which the rate of decrease of the fuel changes as shown by the solid line in FIG. 8 due to vaporization delay or the like when the fire is extinguished, or in the case of the combustion amount, brake the combustion blower 24 from the start of decrease T ₀ to T _03. To rapidly reduce the air volume, and then at time T ₀₃ , the combustion blower 2
The output to 4 is stopped, combustion air is reduced by inertia, and T
Set to zero with ₂ .

By operating in this way, the fuel decreases sharply at one end due to the vaporization delay after extinguishing the fire, but after that,
Even if it is continuously supplied slowly, the mixture concentration during extinguishing operation can be kept constant from the beginning of the supply amount reduction and decreased to extinguish the fire, so the unburned fuel can be reduced and discharged during extinguishing. It is possible to obtain a control device for a combustor with less odor.

Example 5. FIG. 9 is an explanatory view showing a state of reduction of fuel and combustion air at the time of extinguishing a fire of a combustor according to a fifth embodiment of the present invention. In the case of a combustor or a combustion amount in which the rate of decrease of the fuel changes as shown by the solid line in Fig. 9 due to a delay in vaporization during extinguishing, in order to keep the ratio of fuel and combustion air constant from the start of extinguishing, Control is performed so that the rotation speed changes in accordance with the decrease in fuel amount according to the combustor and the combustion amount. Here, the reduction rates of the fuel in FIGS. 7 and 9 are the same for comparison, but when comparing the two, it is clear that the concentration ratio between the fuel and the combustion air in FIG. 9 changes in the best state. There is. In this way, it is possible to extinguish the fire with the concentration ratio of the fuel and the combustion air kept constant with high accuracy, so that the unburned fuel can be reduced even in a combustor having a vaporization characteristic in which the fuel decreases with any transition. It is possible to obtain a control device for a combustor that emits less odor when extinguishing a fire.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing a control device for a combustor according to the present invention.

FIG. 2 is a flowchart showing the operation of the first embodiment of the present invention.

FIG. 3 is a timing chart of voltage waveforms for explaining the operation of the first embodiment of the present invention.

FIG. 4 is a timing diagram of voltage waveforms for explaining a fire extinguishing timing operation according to the first embodiment of this invention.

FIG. 5 is a flowchart showing the operation of the second embodiment of the present invention.

FIG. 6 is a timing chart of voltage waveforms for explaining the operation of the second embodiment of the present invention.

FIG. 7 is an explanatory diagram showing a state of reduction of fuel and combustion air during a fire extinguishing operation according to a third embodiment of the present invention.

FIG. 8 is an explanatory view showing a state of reduction of fuel and combustion air during a fire extinguishing operation according to a fourth embodiment of the present invention.

FIG. 9 is an explanatory diagram showing a state of reduction of fuel and combustion air during a fire extinguishing operation according to a fifth embodiment of the present invention.

FIG. 10 is a cross-sectional view showing a configuration of a combustor used in a conventional liquid fuel combustion device.

FIG. 11 is an explanatory diagram showing how fuel and combustion air are reduced during a fire extinguishing operation in a conventional control device for a combustor.

FIG. 12 is an explanatory diagram showing how fuel and combustion air are reduced in a conventional example.

FIG. 13 is a voltage waveform diagram when braking is applied to the combustion blower in the conventional example.

FIG. 14 is an explanatory diagram showing the state of the reduction rate of fuel and combustion air when the reduction rate of combustion air is high in the conventional example.

FIG. 15 is an explanatory diagram showing the state of the reduction rate of fuel and combustion air when the reduction rate of combustion air is slow in the conventional example.

[Explanation of symbols]

 1 Vaporizer 5 Flame hole 21 Fuel supply means (fuel pump) 24 Combustion blower 25 Control circuit 28 Zero cross pulse generation circuit 29 Signal generation means 31 Firing circuit 32 Thyristor

Claims (5)

[Claims] 1. A vaporizer for vaporizing a liquid fuel, a fuel supply means for supplying the liquid fuel to the vaporizer, a flame hole for burning a premixed gas of the vaporized liquid fuel and combustion air, and a combustion air. And a control circuit for controlling the combustion blower and the fuel supply means, and a zero-cross pulse generating circuit for generating a pulse at a point where the AC power supply voltage crosses zero volt in this control circuit, Signal generating means for outputting an oscillation output signal based on a pulse generated by a zero-cross pulse generating circuit, a thyristor inserted and connected between the combustion blower and the AC power supply voltage,
The thyristor is provided with an ignition circuit that ignites based on the oscillation output signal output from the signal generating means, and at the time of fire extinguishing, the liquid flow rate is reduced and the combustion blower is braked to reduce the air flow rate to extinguish the fire. In a control device for a combustor configured to keep the concentration of a premixed gas in operation within a combustible range, a counter for counting a half cycle of the waveform of the AC power supply voltage is provided in the signal generating means, and the signal generating means is A control device for a combustor, wherein a voltage of 1 / n that outputs only one cycle out of n cycles counted by the counter when extinguishing a fire is applied to a combustion blower to apply a brake. 2. A vaporizer for vaporizing a liquid fuel, a fuel supply means for supplying the liquid fuel to the vaporizer, a flame hole for burning a premixed gas of the vaporized liquid fuel and combustion air, and a combustion air. And a control circuit for controlling the combustion blower and the fuel supply means, and a zero-cross pulse generating circuit for generating a pulse at a point where the AC power supply voltage crosses zero volt in this control circuit, Signal generating means for outputting an oscillation output signal based on a pulse generated by a zero-cross pulse generating circuit, a thyristor inserted and connected between the combustion blower and the AC power supply voltage,
The thyristor is provided with an ignition circuit that ignites based on the oscillation output signal output from the signal generating means, and at the time of fire extinguishing, the liquid flow rate is reduced and the combustion blower is braked to reduce the air flow rate to extinguish the fire. In a control device for a combustor configured to keep the concentration of a premixed gas in operation within a combustible range, a counter for counting a half cycle of the waveform of the AC power supply voltage is provided in the signal generating means, and the signal generating means is Of the n cycles or the m cycles counted by the counter, a 1 / n voltage and a 1 / m voltage that output only one cycle are alternately applied to the combustion blower to apply a brake. Control device. 3. The signal generating means decelerates the combustion blower by inertia for a certain period from the start of extinguishing the fire, and then 1 / n
3. The control device for the combustor according to claim 1, wherein the voltage of 1 or the voltage of 1 / n and the voltage of 1 / m are alternately applied to stop. 4. The signal generation means applies a voltage of 1 / n or a voltage of 1 / n and a voltage of 1 / m alternately to the combustion blower for a certain period from the start of extinguishing to decelerate, and thereafter, The control device for a combustor according to claim 1 or 2, wherein the control device is stopped by inertia. 5. A fuel supply unit for supplying liquid fuel, a combustion blower for supplying combustion air, a control circuit for controlling the combustion blower and the fuel supply unit, and a fuel supply unit for supplying the fuel. A vaporizer for vaporizing the liquid fuel, and a flame hole for burning a premixed mixture of the liquid fuel vaporized by the vaporizer and the combustion air are provided, and during the extinguishing operation, the control circuit sets the concentration of the premixed mixture within a combustible range. A control device for a combustion machine, wherein the combustion blower is stopped while controlling the number of revolutions of the combustion blower so as to keep the above.