JPH04332312A - Burner - Google Patents

Abstract

PURPOSE:To enhance and stabilize ignition performance in its early and long stages and enhance the durability of an ignition electrode with regards to a combustion device used for a fan heater or the like. CONSTITUTION:This combustion device is provided with an ignition electrode 10 as opposed to an ignition burner port 6a. This ignition electrode 10 is arranged to keep a cut off state without deteriorating its tip. Moreover, the electrode 10 is installed at a relatively higher elevation than the burner port 6a and a metal net 7 which covers the burner port 6a is caused to sink in the ignition burner port. Therefore, during the ignition, spark discharge flows up to an upper port edge 6a' of the ignition burner port 6a in a stabilized manner, thereby obtaining stabilized ignition performance. What is more, this construction makes it possible to provide excellent combustion performance from the beginning for long time without damaging the tip of the ignition electrode.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a premix combustion device used in oil fan heaters and the like.

0002

2. Description of the Related Art Conventionally, as shown in FIG. 3, this type of combustion apparatus is constructed by covering the upper opening of a vaporizing cylinder 22 in which a sheathed heater 21 is embedded, and a burner head 23 in the form of a cantilevered cylinder. A mixed gas of vaporized fuel and combustion air supplied into the vaporization cylinder 22 is guided into the burner head 23 and is passed through the flame hole 2.
4 and the ignition flame hole 24a, the flame is ignited by the spark discharge from the ignition electrode 26 via the wire mesh 25, and a flame is formed.

0003

[Problems to be Solved by the Invention] However, in the conventional combustion device described above, in order to improve the ignition performance, the tip of the ignition electrode 26 is made sharp and faces the center of the ignition electrode 24a. The heat capacity decreases, and the part becomes extremely hot during combustion, causing damage if used for a long period of time.In fact, from a lifespan perspective, ignition performance becomes worse, and unburnt gas is generated due to ignition delay, causing odor and CO. occur or
The problem was that it could cause an explosion and ignition, leading to an extremely dangerous situation.

[0004] Also, the tip of the ignition electrode 26 is located at the ignition flame hole 2.
Since the ignition electrode 26 was located at the center of the ignition flame hole 24a, depending on the mounting position of the ignition electrode 26, the spark discharge varied to the top, bottom, right and left of the ignition flame hole 24a, resulting in unstable ignition performance.

The present invention is intended to solve the above-mentioned problems, and aims to improve and stabilize the ignition performance not only in the initial stage but also in the long term, and to improve the durability of the ignition electrode.

[0006]

[Means for Solving the Problems] In order to solve the above-mentioned conventional problems, the present invention provides a shape in which the tip of the ignition electrode is not sharpened but cut, and the tip is positioned upward relative to the ignition flame hole. The wire mesh is recessed into the ignition flame hole of the burner head.

[0007]

According to the present invention, the heat capacity of the tip of the ignition electrode can be ensured by the above-mentioned structure, and even if the electrode is used for a long period of time, the ignition performance will not deteriorate due to breakage of the tip, and the generation of unburned gas and CO will hardly occur. Further, even if the mounting position of the ignition electrode varies, the spark discharge from the ignition electrode always reaches the upper edge of the ignition flame hole, and stable ignition performance can be obtained. In other words, spark discharge is most likely to jump to the point where there is an acute angle. According to the above-described structure of the present invention, the wire mesh is recessed in the ignition flame hole, so that the upper hole edge of the ignition flame hole is at the acute angle. As a result, the spark discharge stabilizes and flies in this area, and the spark discharge always crosses the mixed gas that is easily ejected from the ignition flame hole and diffuses upward, resulting in stable ignition. .

[0008]

[Examples] Examples of the present invention will be described below.

In FIGS. 1 and 2, reference numeral 1 denotes a bottomed cylindrical vaporizing cylinder with an open top, in which a sheathed heater 2 is embedded. Reference numeral 3 denotes a burner head in the form of a cylinder with a ceiling, in which the flange portion of the lower peripheral edge is placed on the opening edge 1a of the vaporizing cylinder 1 and fixed with screws, and the burner head has an outer burner head 3a and an inner burner head 3b press-fitted inside the burner head. It is composed of Above burner head outside 3
A has large through holes 4 all around the peripheral wall, and inside the burner head 3b.
Also, minute through holes 5 are formed all around the peripheral wall, and these through holes are provided on the same axis and set so that they are facing each other,
A flame hole 6 is formed. Further, as flame holes for ignition, a large through hole 4a is formed on the outside 3a of the burner head, and a small through hole 5a is formed inside the burner head 3b, which are larger than the large through hole 4 and the small through hole 5, respectively, and these through holes are coaxial. Ignition flame holes 6a are formed facing each other at the top. Reference numeral 7 denotes a wire mesh stretched around the outer periphery of the burner head 3a and spot welded between the lower through holes on the entire circumference of the peripheral wall, and pressed into depressions in each flame hole 6 and the ignition flame hole 6a.

Reference numeral 8 denotes a vaporizing cylinder cover provided in the burner head 3 to cover the opening of the vaporizing cylinder 1, and the opening at the lower center thereof is narrowed to a small diameter to form a mixed gas inlet 8a. Reference numeral 9 denotes a resistance plate covered over the mixed gas inlet 8a of the vaporizer cylinder lid 8, and 10 an ignition electrode for igniting the mixed gas ejected from the ignition flame hole 6a, the tip of which is pointed as shown in FIG. The flame hole 6a has the same shape as cut, and is provided so as to face the upper position of the ignition flame hole 6a. 11 is a flame, and 12 is a flame rod as a flame detection sensor. Reference numeral 13 denotes a blower tube that sends combustion air into the vaporizer tube 1. An air port 14 at the tip thereof is provided on the wall surface of the vaporizer tube 1, and the other end communicates with a blower. A nozzle 16 is connected to an oil supply pipe 18 from a fuel pump 17, and is exposed to the inside of the carburetor 1 through the inside of the blow pipe 13.

In the above configuration, when the sheathed heater 2 is energized and the vaporizer cylinder 1 is heated to a predetermined temperature, the blower is started and combustion air is introduced into the vaporizer cylinder 1 from the air port 14 via the blower pipe 13. The fuel pump 17 is also started, and fuel is injected into the carburetor cylinder 1 from the nozzle 16 via the oil feed pipe 18. The liquid fuel injected into the vaporization cylinder 1 is vaporized on the heated side wall surface of the vaporization cylinder 1, mixed with combustion air, and then sent to the burner head 3 and ejected from the flame holes 6, 6a. This mixed gas is then ignited by a spark discharge from the ignition electrode 10 to form a flame 11.

[0012] Since the tip of the ignition electrode 10 has a cut shape and is not sharp, sufficient heat capacity can be secured, and even if exposed to flame during combustion, the temperature will not reach a high enough temperature to cause damage. . Therefore, even after long-term use, the positional relationship with the ignition flame hole 6a does not change, the original ignition performance can be maintained, and the generation of unburned gas and CD can be suppressed.

On the other hand, the tip of the ignition electrode 10 has a cut-off shape, and even if its attachment position varies, stable ignition performance can be obtained. In other words, spark discharge is generally most likely to strike at acute angles, but the tip of this ignition electrode 10 is positioned above the ignition flame hole 6a as shown in FIG. The wire mesh 7 disguised as the hole 6a is the ignition flame hole 6a.
Since the hole is recessed inward so that its edge is at an acute angle, the upper edge 10a of the electrode tip and the upper hole edge 10 of the ignition flame hole 6a
a and the upper hole edge 6a' are the closest acute angle portion. Therefore, the spark discharge stably travels along the upper edge 10a and the upper hole edge 6a, and always crosses the mixed gas that is easily ejected from the ignition flame hole 6a and diffuses upward, resulting in stable ignition. It will be done.

Further, since the discharge position of the ignition electrode 10 has little variation as described above, the ignition flame hole 6a can be connected to other flame holes 6.
As it is much larger than this, it is not necessary to make sure that the spark discharge always flies into the ignition flame hole, and therefore, by doing so, it is possible to suppress the lifting of the flame during strong combustion and the increase in the temperature of the wire mesh during weak combustion. This makes it possible to obtain a good combustion state without combustion noise caused by lifting, and to provide a burner with excellent durability of the wire mesh.

[0015]

As explained above, the combustion apparatus of the present invention can suppress the generation of unburned gas, CO, etc. not only in the initial stage but also in the long term, and can obtain stable ignition performance.
It is possible to provide a high-performance combustion device in which the durability of the ignition electrode can also be improved.

[Brief explanation of drawings]

FIG. 1 is an enlarged cross-sectional view of a main part of a combustion device according to an embodiment of the present invention.

FIG. 2 is a sectional view showing the entire combustion device.

FIG. 3 is an enlarged sectional view of a main part of a conventional combustion device.

[Explanation of symbols]

1. Vaporizer cylinder 3 Burner head 6a Ignition flame hole 7. Wire mesh 10 Ignition electrode

Claims (1)

[Claims] Claims: 1. A vaporizer cylinder having an opening, a burner head that covers the opening of the vaporizer cylinder and has an ignition flame hole for ignition at an appropriate position in a surrounding wall, a wire mesh attached to the outer periphery of the burner head, and a and an ignition electrode that ignites the mixed gas ejected from the ignition flame hole, and the ignition electrode has a cut-off tip without being sharpened, and the tip is located at a position relatively above the ignition flame hole. In addition, the wire mesh is recessed in the ignition flame hole of the combustion device.