JPH0330655Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a combustor used in a heater or the like.

BACKGROUND ART Conventionally, this type of combustor is constructed by providing a throat 2 for supplying combustion air on the side wall of a carburetor cylinder 1, and a nozzle 3 for supplying fuel within this throat 2, as shown in FIG. There is. In this combustor, the fuel supplied from the nozzle 3 is vaporized in the vaporization cylinder 1, mixed with air supplied from around the nozzle 3, and then ejected from the flame hole 5 provided in the burner head 4 at the top of the vaporization cylinder and burned. .

Problems to be Solved by the Invention However, in the conventional combustor described above, the nozzle 3 is constantly receiving hot air from the vaporization tube 1, so if the amount of combustion air becomes less than the fuel for some reason, The cooling effect of the combustion air decreases, and the temperature of the nozzle 3 itself increases. As a result, the fuel easily adapts to the nozzle 3, and oil droplets of the fuel tend to accumulate at the tip of the nozzle 3. Furthermore, since the amount of air flowing around the nozzle is small, it becomes difficult to blow away oil droplets that accumulate at the tip of the nozzle 3. Therefore, the fuel oil droplets at the tip of the nozzle 3 grow larger. These oil droplets gradually fall into the vaporizer cylinder 1 due to their own weight, and the next oil droplet grows at the tip of the nozzle 3, a phenomenon that is periodically repeated. When these oil droplets fall when combustion is stopped, they vaporize and become residual unburned gas, causing odor, or they do not vaporize and cause tar formation. Furthermore, when oil droplets fall during normal combustion, the temperature of the vaporizer cylinder 1 drops temporarily,
The oil droplets evaporate with a delay after the amount of evaporation decreases. In other words, in the combustion section, the moment these oil droplets fall, the fire becomes smaller, and then a pulsating combustion occurs where the amount of fuel vaporized gas is higher than usual and a fire starved of air occurs until all the fallen oil droplets are vaporized. Become. The larger the oil droplets that fall here, the larger the pulsating combustion described above will become, eventually producing yellow flame, soot, and odor, and also causing the combustion detection based on the output current value of the flame rod 6 to malfunction. I feel tired.

Furthermore, the above-mentioned phenomenon is more likely to occur during low combustion when the force of fuel discharge from the nozzle 3 is low and the amount of air flowing around the nozzle 3 is small. easy. For example, this is likely to occur if the tip of the nozzle 3 is rough due to machining, or dirt such as cutting chips adheres to it, or tar or dirt accumulates on the nozzle 3 over time, and the amount of combustion air is less than that of fuel. There were also problems that occurred even when there was no such thing.

The present invention was developed in view of the above-mentioned conventional problems, and is designed to prevent fuel oil droplets from accumulating at the tip of the nozzle, and even if they do accumulate, to prevent the oil droplets from growing large, so that the combustion conditions may change somewhat. The purpose of this is to obtain a combustor that can provide good combustion conditions even when the combustion rate is low, and that has a wide variable range of combustion amount.

Means for Solving the Problems In order to solve the above problems, the combustor of the present invention has a structure in which the tip of the nozzle is treated with oil repellent treatment.

Effects The present invention has the above-described structure, so that even if oil droplets try to accumulate at the tip of the nozzle, the oil droplets are repelled by the oil repellent treatment and are blown away by the air flowing around the nozzle, resulting in vaporization. This will no longer affect the vaporization in the cylinder and the combustion in the combustion section.

Embodiment An embodiment of the present invention will be described below with reference to FIGS. 1 and 2. Reference numeral 11 is a combustion blower with a built-in fan motor; Air pipe 14 to 13
It is connected to. 15 is a variable damper provided on the air pipe 14; 16 is a bypass air passage branched from between the variable damper 15 and the combustion blower 11; and the burner case 1 is arranged to cover the vaporization cylinder 12.
It is connected to 7. Reference numeral 18 denotes a nozzle that faces into the vaporizing cylinder 12 through the inside of the throat 13, and is connected to the oil tank receiver 19 via a pump 20. As shown in FIG. 1, this nozzle 18 is coated with a heat-resistant and oil-repellent coating 21 such as fluorine resin on at least its outer periphery. Note that 22 in the figure is a cartridge tank that replenishes the oil tank receiver 19 with fuel. A sheathed heater 23 is embedded in the outer periphery of the vaporization tube 12, and is designed to maintain the vaporization tube 12 above a certain temperature using a temperature controller or the like. A burner head 24 covers the upper part of the vaporizing cylinder 12 and has a flame hole 25 around its outer periphery. 26 is a flame rod provided opposite to this flame hole 25.

In the above configuration, fuel is sucked up from the oil tank receiver 19 by the pump 20 and is injected into the vaporization cylinder 12 from the nozzle 18. The inside of the vaporizing cylinder 12 is heated to a high temperature by a sheathed heater 23, and the ejected fuel is vaporized, mixed with air sent from the throat 13, and ejected from the flame hole 25 of the burner head 24. When the mixed gas is ignited by an appropriate means, a flame is formed in the flame hole 25. At this time,
When a constant voltage is applied between the flame rod 26 and the burner head 24, a large amount of current flows during normal combustion, and a small amount of current flows during abnormal combustion, so the combustion state can be detected from this current value. , it is possible to prevent abnormal combustion. Furthermore, if the amount of air jetted out from the throat 13 is varied by the variable damper 15 in accordance with the amount of fuel sucked up and supplied by the pump 20, the amount of combustion can be changed.

Here, the coating 2 applied to the tip of the nozzle 18
No. 1 has oil repellency against fuel, so even if the fuel discharged from the tip of the nozzle 18 attempts to reach the outer periphery of the nozzle, this is prevented. Furthermore, even if the oil droplets reach the outer periphery of the nozzle, they are repelled before they grow into large oil droplets and are immediately blown away by their own weight and air flow. Therefore, first, when combustion is stopped, large oil droplets accumulate at the tip of the nozzle 18, and these large oil droplets drip into the vaporizer cylinder, producing a large amount of unburned gas, producing a strong odor, and causing tar formation. The problem will go away. In addition, even under normal conditions, oil droplets will not fall and cause the flame in the combustion section to disturb and cause pulsating combustion, which will cause yellow flame, soot, and odor, and will also prevent malfunctions in combustion detection based on the output current value of the flame rod 25. You won't have to worry about it happening at all. In other words, even if the tip of the nozzle 18 is somewhat rough due to machining, it does not matter at all, it widens the variation in the air-to-fuel ratio, provides a good combustion state even if the combustion conditions change slightly, and has a wide range of variable combustion amount. You will be able to do it.

In the above embodiment, the oil-proofing treatment is applied to the outer peripheral portion of the nostle 18, but the same effect can be obtained even if the oil-proofing treatment is applied to both the inside and outside surfaces.

Effects of the invention As described above, according to the invention, since the tip of the nozzle is made oil-repellent, oil droplets are less likely to accumulate in the nozzle, and even if oil droplets do accumulate, they can be blown away before they grow large. Therefore, even if the variation in the air to fuel ratio increases and the combustion conditions change somewhat, a good combustion state can be obtained over a long period of time, and the combustion variable range can be widened.

[Brief explanation of the drawing]

FIG. 1 is an enlarged sectional view of a main part of a combustor according to an embodiment of the present invention, FIG. 2 is a sectional view of the entire combustor, and FIG. 3 is a sectional view showing a conventional combustor. 12... Vaporizer tube, 13... Throat, 18...
Nozzle, 21...Oil repellent treatment (film).

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A bottomed cylindrical vaporization tube that vaporizes liquid fuel, premixes the vaporized gas and combustion air, and supplies the mixture to the combustion section, and a tip that faces inside the vaporization tube. A combustor comprising a nozzle for ejecting and supplying liquid fuel, and a throat for supplying combustion air arranged around the nozzle, the nozzle having an oil-repellent treatment applied to its tip. (2) Claim No. 1 for Utility Model Registration that the oil-repellent treatment at the tip of the nozzle is a fluororesin coating treatment.
Combustor described in section.