JP3843882B2 - Liquid fuel combustion equipment - Google Patents

Description

[0001]
[Field of the Invention]
The present invention relates to a liquid fuel combustion apparatus mounted on a domestic water heater or heater.
[0002]
[Prior art]
As a conventional liquid fuel combustion apparatus of this type, there has been one as described in JP-A-8-21606.
[0003]
FIG. 3 shows the configuration, 1 is a pump supplied with liquid fuel, 2 is a supply pipe for the liquid fuel, 3 is a nozzle from which liquid fuel is ejected, 4 is an electric heater, and 5 is an electric heater 4 embedded therein. The carburetor, 6 is a blower fan for sending combustion air, 7 is a blower passage for introducing the combustion air into the vaporizer 5, and 8 is a primary air passage provided in the blower passage 7.
[0004]
Reference numeral 9 denotes a mixing chamber for uniformly mixing the air-fuel mixture mixed with the fuel vaporized by the carburetor 5, 10 denotes a burner head provided above the mixing chamber 9, and 11 denotes a flame opening provided in the burner head 10. , 12 is a secondary air passage provided in the vicinity of the flame opening 11, 13 is a secondary air opening provided in the upper portion of the secondary air passage 12, and 14 is a side of the carburetor 5. A heat receiving fin 15 projecting upward from the portion 11 is disposed at the inlet of the primary air passage 8 and changes the cross-sectional area of the air passage 7 by opening and closing, and the amount of air that substantially closes the primary air passage 8 when closed. The adjusting means 16 is a combustion flame formed on the flame opening 11.
[0005]
When the vaporizer 5 is heated to a predetermined temperature by the electric heater 4, the liquid fuel is sent as droplets from the nozzle 3 to the vaporizer 5 through the feed pipe 2 and is heated and vaporized. The
[0006]
On the other hand, the combustion air passes through the air passage 7 by the blower fan 6, and a part of the air is introduced into the carburetor 5 from the primary air passage 8, and is mixed with the vaporized fuel to form an air-fuel mixture. After being mixed uniformly, it reaches the flame opening 11 where a blue combustion flame 15 is formed and burned.
[0007]
The remaining air is supplied from the secondary air passage 1 to the secondary air port 13 provided in the vicinity of the flame port 11 and contributes to combustion.
[0008]
When the combustion amount is large, the air amount adjusting means 14 is opened and a large amount of air is introduced into the carburetor 5 to promote combustion. When the combustion amount is small, the primary air passage 8 is closed and combustion is performed. The air pressure was increased to improve the wind resistance and expand the combustion range.
[0009]
[Problems to be solved by the invention]
However, in the conventional configuration, the carburetor 5 receives heat supply from the combustion flame via the heat receiving fins 14 during combustion. In order to compensate for this amount of heat received, the electric heater 4 is repeatedly activated and stopped. For this reason, much electric power is consumed.
[0010]
Here, in order to reduce the power consumption of the electric heater 4 during combustion, the amount of heat received should be increased by improving the shape of the heat receiving fins 14 of the vaporizer 5 and increasing the ability of the flame 16 near the heat receiving fins 14. That's fine.
[0011]
However, if the amount of heat received is increased and the electric heater 4 stops operating during combustion, the temperature of the carburetor 5 will depend on the combustion flame 16, so that control becomes impossible and the combustion amount is reduced from the rated combustion. In the entire region, there was a combustion amount exceeding the heat resistance limit temperature (400 ° C.) of the material of the vaporizer 5 (aluminum die casting), which had the problem of causing deformation of the heat receiving fins 14.
[0012]
The present invention solves the above-mentioned conventional problems, and provides a combustion apparatus that prevents the deformation by preventing the temperature from exceeding the heat-resistant limit temperature, assuming the temperature within the entire combustion region of the heat receiving portion of the vaporizer. The purpose is to do.
[0013]
[Means for Solving the Problems]
In order to solve the above-described conventional problems, the liquid fuel combustion apparatus of the present invention has a heating means, and vaporizes the liquid fuel, and the fuel vaporized by the vaporizer is mixed with combustion air for combustion. Receiving the signal of the vaporizer temperature detection unit, the heat receiving unit of the vaporizer provided in the vicinity of the flame port, the vaporizer temperature detection unit detecting the temperature of the vaporizer, and the vaporizer temperature detection unit controls the operation of the heating means, the vaporizer temperature detector signal assumes the temperature of the heat receiving portion of the vaporizer from, or be higher this assumed temperature is higher than the stop temperature of operation of the heating means And a controller that reduces the supply of liquid fuel when the temperature of the heat receiving part of the carburetor does not exceed the heat resistance limit temperature in the entire combustion region. Durability can be improved.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
The present invention includes a vaporizer that has heating means and vaporizes liquid fuel, a flame port that mixes the fuel vaporized by the vaporizer with combustion air and burns, and is provided close to the flame port. And a vaporizer temperature detector for detecting the temperature of the vaporizer, and controls the operation of the heating means in response to a signal from the vaporizer temperature detector , and the vaporizer temperature detector. from signal assuming a temperature of the heat receiving portion of the carburetor, when it is expected that becomes or higher becomes higher than the stop temperature of the working of the assumed temperature heating means, control to reduce the supply of the liquid fuel And the temperature of the heat receiving portion of the vaporizer is set so as not to exceed the heat resistant limit temperature in the entire combustion region.
[0015]
As another form, when it is predicted that the temperature of the heat receiving unit becomes higher or higher than the temperature at which the operation of the heating unit is stopped, the control unit reduces the supply of liquid fuel and the supply amount of air If it is made variable, combustion itself can be maintained satisfactorily. In response to the signal from the vaporizer temperature detection unit, the controller measures the rate of temperature rise within a predetermined time, evaluates the rapid temperature rise change, and predicts that it will be higher than the stop temperature of the operation of the heating means. I have to.
[0016]
As another embodiment, the control unit gives an instruction after correcting the increase or decrease of the temperature of the heat receiving unit assumed based on the relationship between the vaporizer temperature and the temperature of the combustion air. Further, the control unit may reduce the stop temperature of the operation of the heating unit when the temperature of the heat receiving unit is expected to be higher or higher than the stop temperature of the heating unit during the operation of the heating unit. Good.
[0017]
Furthermore, the control part can also consider the form which sets the stop temperature of the action | operation of a heating means until the time of ignition so that it may become lower than the stop temperature after ignition.
[0018]
If these liquid combustion devices are installed in a hot water heater or a heater, the efficiency and safety will be excellent.
[0019]
【Example】
Embodiments of the present invention will be described below with reference to the drawings. In FIG. 1, a fuel pump 17 pumps liquid fuel such as kerosene from a fuel tank (not shown) and supplies the fuel supply nozzle 18 via a feed pipe 19. The carburetor 20 provided in front of the fuel supply nozzle 18 has a cylindrical shape and is made of a material having excellent heat resistance such as aluminum alloy such as aluminum and duralumin, brass, copper, steel, cast iron and the like. ing.
[0020]
On the side surface of the vaporizer 20, a vaporizer lid 22 that is partially opened is provided so that the end of the blower tube 21 faces. The vaporizer lid 22 is made of a material having good heat conductivity such as aluminum, brass, copper, cast iron or the like. The fuel supply nozzle 18 is inserted into the blower pipe 21 toward the vaporizer 20. At the lower part of the vaporizer 20, an air-fuel mixture outlet 23 constituted by a vaporizer lid 22 is provided.
[0021]
Reference numeral 24 denotes a conveyance passage which is provided below the air-fuel mixture outlet 22 and is formed in a bowl shape with a material having good heat conductivity such as aluminum, brass, copper, cast iron or the like. The conveyance path 24 is provided with a depression 25 in a portion located below the air-fuel mixture outlet 23, and constitutes an inclined portion 26 from the depression 25 to the end of the conveyance path 24 formed in a bowl shape.
[0022]
A porous flame opening 27 made of a heat-resistant material such as steel, iron, titanium, duralumin, or ceramic is provided downstream of the conveyance passage 24. The flame opening 27 is placed on the transport passage 24 together with the vaporizer 20.
[0023]
Reference numeral 28 denotes a burner case covering the entire combustion portion, and an inner space is an air passage 29 provided so as to surround the periphery of the carburetor 20, the conveyance passage 24, and the flame opening portion 27.
[0024]
Reference numeral 30 denotes a cylindrical secondary air passage provided so as to divide the flame opening 27 into a plurality of parts, and both ends thereof are open to the air passage 29. A plurality of secondary air outlets 31 facing the downstream side of the flame outlet 27 are provided. The plurality of flame outlets 27 and the secondary air passage 30 are arranged in parallel to the vaporizer 20.
[0025]
The flame opening 27 and the secondary air passage 30 are configured to be flush with each other toward the downstream side. An end of the secondary air passage 30 is communicated with the air passage 29.
[0026]
The structural combination of the flame outlet 27 and the secondary air passage 30 is that the side adjacent to the vaporizer 20 is the flame outlet 27 and the side adjacent to the opposite air passage 29 is the secondary air passage 30. Configure as follows.
[0027]
Reference numeral 32 denotes a side wall provided between the flame opening portion 27 and the air passage 29, and a combustion chamber 33 is formed inside thereof. The flame opening 27 is attached by performing a plurality of spot weldings on a part of the secondary air passage 30 together with the secondary air passage 30 at the end on the transport passage 24 side.
[0028]
Reference numeral 34 denotes a fin-shaped heat receiving portion that is divided into a plurality of parts so as to protrude from the back surface of the vaporizer 20 to the combustion chamber 33. The heat receiving portion 34 is configured at a position so as to protrude above the flame opening portion 27.
[0029]
A heat exchanger 35 is placed on the top plate portion 36 of the air passage 29 so as to cover the top of the flame opening portion 27. The heat exchanger 35 is formed in a cylindrical shape using heat-resistant copper or aluminum material having good heat conduction, and a plurality of plate-like fins are provided in a plurality of hot water pipes in the middle.
[0030]
37 is a blower for supplying combustion air. The impeller is configured to use a turbo fan, a radial fan, or the like that can generate high pressure, and is rotated by a motor, and is communicated with a part of the side of the air passage 29. The air passage 38 is connected.
[0031]
The blower pipe 21 is provided in the blower passage 38. The blower pipe 21 is provided with a plurality of communication ports 39 communicating with the blower passage 38 at a position before being inserted into the vaporizer lid 22.
[0032]
Reference numeral 40 denotes a vaporizing air conditioner provided in the air passage 38, and a drive for rotationally driving the closing damper 41 and the upper damper 42 that change the air blowing resistance of the air blowing pipe 21 by opening and closing, and the closing damper 41 and the upper damper 42. The apparatus 43 is comprised.
[0033]
The closing damper 41 and the upper damper 42 are provided so as to rotate coaxially with the plate surfaces of the two plates as axes, and may be opened or closed in the vertical direction or opened in the horizontal direction. The closing damper 41 is provided on the side that comes into contact with the inlet of the blower pipe 21, and a plurality of through holes 44 are provided in part.
[0034]
The upper damper 42 is provided at a position overlapping the outside of the closing damper 41, and in the region mode including the minimum combustion amount, substantially contacts the closing damper 41, substantially closes the through hole 44, and has an intermediate combustion amount region. In this mode, an angle is provided between the closed damper 41 and the through hole 44 is opened.
[0035]
In the mode including the region where the combustion amount is maximum, both the closing damper 41 and the upper damper 42 are opened, and the entrance of the blower pipe 21 is expanded to the maximum. The drive device 43 is configured by using a stepping motor, a solenoid, a motor, a gear, a cam, and the like so that the closing damper 41 and the upper damper 42 perform respective operations, and the drive portion of the driving device 43 is connected to the closing damper 41. It is connected to the upper damper 42.
[0036]
Reference numeral 45 denotes a heating means using an electric heater, which is composed of a heating element such as a nichrome wire or a Kanthal wire cast into the vaporizer 20.
[0037]
Reference numeral 46 denotes a vaporizer temperature detection unit for detecting the temperature of the vaporizer 20, and includes a thermistor, a thermocouple, and the like.
[0038]
Reference numeral 47 is a control unit for operating and stopping the heating means 45 from the signal of the vaporizer temperature detection unit 46 to maintain the vaporizer 20 at a predetermined temperature.
[0039]
The control unit 47 controls the fuel pump 17 and the blower 37 to an appropriate state according to the instruction of the operation switch and the size of the load. More specifically, the control unit 47 receives a signal from the vaporizer temperature detection unit 46 and receives the signal from the vaporizer 20. The temperature of the heat receiving part 34 is assumed . Since there is a certain temperature difference between the temperature of the portion where the vaporizer temperature detection unit 46 of the vaporizer 20 is installed and the portion where the temperature at the tip of the heat receiving unit 34 is high due to the combustion state, the control unit 47. Thus , when it is predicted that the temperature of the heat receiving section 34 is higher or higher than the stop temperature of the operation of the heating means 45 (that is, this temperature is also the ON / OFF OFF temperature of the vaporizer 20) . The fuel pump 17 is varied to reduce the supply of liquid fuel.
[0040]
The controller 47 stores the correlation data between the signal of the carburetor temperature detecting unit 46 during combustion after the heating means 45 is stopped and the temperature of the heat receiving unit 34 for each combustion amount, and the temperature of the heat receiving unit 34 is assumed. It can be done.
[0041]
48 indicates a flame formed in the flame opening 27, 49 indicates an air flow, and 50 indicates an air-fuel mixture flow.
[0042]
In the liquid fuel combustion apparatus configured as described above, when a power source (not shown) is turned on, the heating means 45 is energized and the vaporizer 20 is heated. When the vaporizer 20 reaches a predetermined temperature (this temperature is a temperature at which the liquid fuel can be vaporized in the vaporizer 20, and is set to 230 to 240 ° C. in the vaporizer temperature detection unit 46), the vaporizer temperature detection unit The air blower 37 is actuated by an instruction from the controller 47, and combustion air is supplied.
[0043]
The air 49 supplied to the air passage 38 is adjusted in the amount of air by the closing damper 41 and the upper damper 42 of the vaporizing air regulator 40, and then the primary air and the secondary air passage 30 are supplied into the air pipe 21. And the secondary air supplied to the air.
[0044]
At the same time, the fuel pump 17 is operated, and fuel is sprayed from the fuel supply nozzle 18 to the vaporizer 20. The fuel is vaporized on the wall surface of the high-temperature carburetor 20 and mixed with the air 49 supplied through the blower pipe 21, and is then transported to the transport passage 24 through the air-fuel mixture outlet 23 to become the air-fuel mixture 50. 27.
[0045]
Further, an air-fuel mixture 50 ejected from the flame opening 27 is ignited by an ignition electrode (not shown) that has been previously subjected to spark discharge, and a flame 48 is formed to start combustion.
[0046]
Thereafter, the vaporizer 20 continues to be heated by the heat receiving part 34 receiving the heat of the flame 48. The state of the flame 48 formed in the flame opening 27 is monitored by a flame detection unit (frame rod: not shown), and stable combustion is continued. Further, the high-temperature combustion gas generated by the combustion is heat-exchanged by the heat exchanger 35 and discharged.
[0047]
Here, the vaporizer 20 is heated by the heat of the flame 48, and the temperature at which the liquid fuel can be vaporized by the vaporizer temperature detection unit 46 (for example, the vaporizable temperature is 120 ° C., which is the saturated vapor temperature of the liquid fuel). The operation of the heating means 45 is stopped after confirming that the temperature can be maintained at a temperature up to 280 ° C. (100% evaporation temperature).
[0048]
When the carburetor 20 receives sufficient heat from the heat receiving unit 34 and is maintained at a temperature that does not require the heating means 45, the control unit 47 vaporizes the fuel pump 17 and the blower 37 according to the operation switch instruction and the magnitude of the load. The air conditioner 40 is controlled so as to freely change between a mode including a region including the minimum combustion amount, a mode including a region where the combustion amount is intermediate, and a mode including a region including the maximum combustion amount.
[0049]
The vaporizer temperature detection unit 46 evaluates the temperature of the heat receiving unit 34 while monitoring the temperature during this period. Compared with the temperature monitored by the vaporizer temperature detection unit 46, the temperature of the heat receiving unit 34 is increased at a constant rate, so the temperature of the heat receiving unit 34 is assumed. In the normal operation of the combustion apparatus, the assumed temperature of the heat receiving section 34 is equal to or lower than the heat resistant limit temperature of the material of the vaporizer 20 (for example, 400 ° C. when the material of the vaporizer 20 is aluminum die casting).
[0050]
However, for example, when a strong wind hits a device equipped with a combustion device and air cannot be sufficiently supplied to the combustion device, a flame is brought into close contact with the flame outlet 27, the temperature of the flame outlet 27 is increased, and the surroundings become red hot. Increase temperature.
[0051]
At this time, the amount of cooling by the excess air in the flame 48 is reduced in the heat receiving part 34 of the vaporizer 20 and the amount of cooling by the air in the vaporizer 20 is also reduced to exceed the heat resistant limit temperature, and the heat received by the vaporizer 20. Since the part 34 is deformed, the controller 47 that receives the signal from the vaporizer temperature detector 46 assumes the temperature of the heat receiving part 34 of the vaporizer 20, and the temperature of the heat receiving part 34 stops the operation of the heating means 45. When the temperature is higher or higher than the temperature, an instruction is sent to the fuel pump 17 to reduce the liquid fuel supply.
[0052]
Since the supply amount of the air 49 by the blower 37 is fixed, the flame 48 is in an excess air state by reducing the combustion amount, and the combustion amount is also reduced, so the amount of heat received by the heat receiving unit 34 is reduced. This greatly reduces the temperature of the heat receiving section 34, prevents thermal deformation of the vaporizer 20 and the heat receiving section 34, and improves the durability of the combustion apparatus.
[0053]
Further, due to variations in equipment of the fuel pump 17 and the blower 37, variations in assembly of the combustion apparatus, changes in temperature, etc., a change in the mixing ratio of the fuel and air and a change in the flame holding state of the flame 48 occur. Therefore, the controller 47 that receives the signal from the vaporizer temperature detection unit 46 assumes the temperature of the heat receiving unit 34 of the vaporizer 20, and the temperature of the heat receiving unit 34 is the temperature of the heating unit 45. When the temperature is higher or higher than the operation stop temperature, an instruction is sent to the fuel pump 17 to reduce the amount of liquid fuel supplied and to reduce the amount of combustion, thereby reducing the amount of heat received by the heat receiving section 34. Thus, the temperature of the heat receiving portion 34 can be lowered and deformation can be prevented.
[0054]
Further, when it can be assumed that the temperature of the heat receiving unit 34 is equal to or lower than the heat resistant limit temperature based on the value of the vaporizer temperature detecting unit 46, the control unit 47 sends an instruction to the fuel pump 17 to increase the supply of liquid fuel. An instruction to return to the supply amount can be given, and a stable combustion amount can be maintained.
[0055]
Also for the flame 48 on the flame opening 27 of the present embodiment, the controller 47 reduces the supply of the liquid fuel of the fuel pump 17 by the temperature indicated by the vaporizer temperature detector 46, so that the flame 48 is short of air. Can be eliminated to prevent soot from occurring.
[0056]
When the transport passage 24 is made of copper having good heat conduction, the controller 47 reduces the supply of liquid fuel from the fuel pump 17 according to the temperature indicated by the vaporizer temperature detector 46, thereby reducing the combustion amount and reducing the flame. Radiant heat from the port 27 can be prevented, high temperature oxidation of copper can be prevented, and durability of the transport passage 24 can be improved.
[0057]
In the above embodiment, the control unit 47 receives the signal from the vaporizer temperature detection unit 46 and instructs the fuel pump 17 to reduce the supply of the liquid fuel, but simultaneously instructs the blower 37, It is also conceivable to vary the air supply amount in accordance with the decrease in the fuel supply amount.
[0058]
More specifically, the control unit 47 receives a signal from the vaporizer temperature detection unit 46, and when the value exceeds or exceeds the heat resistant limit temperature of the material of the vaporizer 20, the fuel pump 17 is sent, the amount of liquid fuel supplied is decreased, the amount of heat received by the heat receiving portion 34 of the vaporizer 20 is reduced by reducing the amount of combustion of the flame 48, and the temperature of the heat receiving portion 34 is lowered, Further, an instruction is sent to the blower 37 to reduce the supply amount of the air 49 to an optimal distribution to the supply amount of the liquid fuel, and while maintaining the combustion state of the flame 48 at the optimal state of the supply amount of the liquid fuel, The temperature of the heat receiving part 34 is lowered.
[0059]
In this way, by setting the distribution of the combustion amount of the flame 48 and the air amount formed in the flame port 27 to appropriate values, the optimum temperature of the heat receiving portion 34 for each combustion amount is created from the combustion state, The temperature of the heat receiving part 34 can be surely suppressed below the heat resistant limit temperature of the material of the vaporizer 20, and thermal deformation of the vaporizer 20 and the heat receiving part 34 can be prevented.
[0060]
Further, when the temperature rise of the vaporizer temperature detection unit 46 exceeds the rate of increase within a predetermined time while the operation of the heating unit 45 is stopped, the control unit 47 sends an instruction to the fuel pump 17 to stop the supply of liquid fuel. You may make it do.
[0061]
That is, when the control unit 47 receives the signal from the vaporizer temperature detection unit 46, the value is a temperature that is more rapid than the normal temperature increase curve (temperature increase rate within a predetermined time stored as data in the control unit 47). If there is an increase, the combustion state of the flame 48 in the vicinity of the heat receiving portion 34 of the vaporizer 20 has changed, and it is assumed that an abnormality has occurred in the combustion device, and the fuel pump 17 is stopped (for example, There is a case where the exhaust portion of the combustion device is suddenly short of air, and the carburetor temperature detection unit 46 may greatly fluctuate).
[0062]
Thus, the rapid temperature rise of the heat receiving part 34 of the vaporizer 20 can be prevented, and damage to the combustion apparatus can be prevented.
[0063]
Furthermore, the control unit 47 determines that the temperature of the heat receiving unit 34 is maintained during the operation of the heating unit 45 (a state in which the temperature of the vaporizer 20 is maintained within a certain temperature range by repeatedly operating and stopping the heating unit 45). It is also conceivable to lower the operation stop temperature of the heating means 45 when it is expected to be higher or higher than the operation stop temperature.
[0064]
That is, the control unit 47 receives the signal from the vaporizer temperature detection unit 46 and repeats the operation and stop of the heating unit 45 so that the temperature of the heat reception unit 34 exceeds or exceeds the heat resistant limit temperature of the material of the vaporizer 20. If this is predicted, the stop temperature of the heating unit 45 is lowered to prevent an increase in the temperature of the heat receiving unit 34 due to overshoot after the heating unit 45 stops, and the temperature of the heat receiving unit 34 is always kept at the vaporizer 20. The heat resistance limit temperature of the material is not exceeded.
[0065]
As described above, by preventing the temperature rise (overshoot) of the heat receiving section 34 after the heating means 45 is stopped, the temperature of the heat receiving section 34 does not exceed the heat resistant limit temperature of the material of the vaporizer 20, and combustion The durability of the apparatus can be improved.
[0066]
Furthermore, it is conceivable to set the stop temperature of the operation of the heating means 45 at the time of ignition lower than the stop temperature after the ignition via the control unit 47.
[0067]
That is, the control unit 47 receives the signal from the carburetor temperature detection unit 46, and when the carburetor 20 is preheated and ignites when the combustion apparatus is started, the heat receiving unit 34 receives the heat of the flame 48 and the heating means 45. Heat is applied at the same time. Particularly, as the flow rate characteristic of the fuel pump 17, when the supply amount increases from the set value at the start or when a large combustion amount is used from the start of the combustion device, excessive heat is applied to the heat receiving section 34. As a result, the stop temperature of the operation of the heating means 45 is lowered only at the start, the heating means 45 is stopped early, temperature rise (overshoot) of the heat receiving part 34 is prevented, and the temperature of the heat receiving part 34 is vaporized. Do not exceed 20 heat limit temperature.
[0068]
As described above, in this embodiment, by suppressing the heating unit 45 in accordance with the increase in the amount of heat received due to the increase in the combustion amount at the time of ignition, the temperature rise (over) of the heat receiving unit 34 after the heating unit 45 is stopped. Chute) can be prevented, and the temperature of the heat receiving section 34 can be prevented from exceeding the heat resistance limit temperature of the vaporizer 20.
[0069]
FIG. 2 shows another embodiment, in which the controller 47 corrects the temperature of the heat receiving unit 34 assumed by receiving the signal of the carburetor temperature detecting unit 46 by the signal of the supply air temperature detecting unit 51 and supplies the fuel pump 17 to the fuel pump 17. Instructions were given.
[0070]
In this way, the control unit 47 receives the signal from the carburetor temperature detection unit 46 and corrects the temperature of the heat receiving unit 34 that is assumed by the signal from the supply air temperature detection unit 51 to give an instruction. An instruction is given by grasping the temperature level and converting the prediction of the temperature change of the heat receiving section 34 of the vaporizer 20.
[0071]
At this time, in summer when the supply air temperature is likely to rise, the temperature of the carburetor temperature detection unit 46 is estimated to be higher, and in winter when the supply air temperature is lowered, the temperature of the carburetor temperature detection unit 46 is estimated to be lower. Thus, the accuracy of the temperature of the heat receiving part 34 is improved.
[0072]
As described above, in the present embodiment, the temperature of the vaporizer temperature detection unit 46 can be grasped more accurately, and the temperature of the heat receiving unit 34 of the vaporizer 20 can be accurately estimated from the result. The timing at which the amount is reduced can be accurately measured, and the temperature of the heat receiving section 34 can be maintained below the heat resistant limit temperature of the vaporizer 20 to prevent deformation of the heat receiving section 34.
[0073]
As mentioned above, the embodiments of the liquid fuel combustion apparatus of the present invention have been described. However, if these are mounted on a hot water heater or a heater, the operational reliability is high and the durability can be improved. is there.
[0074]
【The invention's effect】
As described above, according to the present invention, the temperature of the heat receiving portion of the vaporizer is prevented from exceeding the heat resistant limit temperature of the vaporizer material in the entire combustion region, so that the deformation of the vaporizer and the heat receiving portion is prevented. The durability of the combustion device can be improved. Moreover, if it mounts in a water heater or a heater, those commercial values can be raised remarkably.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a liquid fuel combustion apparatus according to an embodiment of the present invention. FIG. 2 is a cross-sectional view of a liquid fuel combustion apparatus according to another embodiment of the present invention. [Explanation of symbols]
20 Vaporizer 27 Flame Port 34 Heat Receiving Unit 45 Heating Means 46 Vaporizer Temperature Detection Unit 47 Control Unit

Claims (8)

A vaporizer that has heating means and vaporizes liquid fuel, a flame port that mixes the fuel vaporized by the vaporizer with combustion air and burns it, and a vaporizer that is provided close to the flame port And a vaporizer temperature detector for detecting the temperature of the vaporizer, and controls the operation of the heating means in response to a signal of the vaporizer temperature detector, and vaporizes from the signal of the vaporizer temperature detector And a controller that reduces the supply of liquid fuel when the estimated temperature is assumed to be higher or higher than the temperature at which the heating means is stopped. Liquid fuel combustion device. When the temperature of the heat receiving unit of the vaporizer is predicted to be higher or higher than the stop temperature of the operation of the heating means from the signal of the vaporizer temperature detection unit , the control unit reduces the supply of liquid fuel and 2. The liquid fuel combustion apparatus according to claim 1, wherein the supply amount of air is variable. 2. The liquid fuel combustion apparatus according to claim 1, wherein the controller stops the supply of the liquid fuel when the temperature rise at the vaporizer temperature detector exceeds the rate of increase within a predetermined time from the signal of the vaporizer temperature detector . 3. The control unit receives the signal from the supply air temperature detection unit, corrects the temperature of the heat receiving unit assumed from the signal from the vaporizer temperature detection unit, and newly assumes the temperature of the heat receiving unit. The liquid fuel combustion apparatus according to any one of claims 1 to 3, wherein the supply of the liquid fuel is reduced when the temperature becomes higher or higher than the operation stop temperature . The control unit receives the signal from the supply air temperature detection unit during operation of the heating unit, and when the temperature of the heat receiving unit is predicted to be higher or higher than the stop temperature of the heating unit, The liquid fuel combustion apparatus according to claim 1, wherein the stop temperature is lowered. The liquid fuel combustion apparatus according to any one of claims 1 to 5, wherein the control unit sets the stop temperature of the operation of the heating means until ignition to be lower than the stop temperature after ignition.   A water heater equipped with the liquid fuel combustion apparatus according to any one of claims 1 to 6.   A heater equipped with the liquid fuel combustion apparatus according to any one of claims 1 to 6.

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