JPH045879Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a liquid fuel burner used in water heaters, bathtubs, etc.

[Conventional technology]

Conventionally, so-called gun-type burners have been widely used as burners for water heaters, bathtubs, etc. that use kerosene as fuel.

As shown in FIG. 2, the basic structure of a conventional gun-type burner is that a nozzle 1 and a flame-holding plate 2 are arranged inside a cylindrical combustion tube 3, and kerosene is pressurized by a pump 4 and sprayed from the nozzle 1. The combustion air supplied from the blower 5 is mixed with an igniter (not shown).
etc., a flame is formed on the surface of the flame-holding plate, and combustion occurs.

These gun-type burners are usually equipped with a flame detector 6 such as CdS (cadmium sulfide cell) or flame rod to detect the presence or absence of flame and control the operation of water heaters, bathtubs, and other equipment for equipment safety. It is being

[Problem that the invention attempts to solve]

Usually, in gun-type burners, CdS is used as a flame detector rather than flame rod because (1) prevention of deterioration of sensitivity due to soot adhesion is prevented, and (2) control circuit configuration is simple and inexpensive. This occurs in many cases. Figure 3 shows the shape of commonly used CdS. In FIG. 3, 11 is a mounting base, 12 is a main body casing, and 13 is a light receiving section. Although CdS has the above-mentioned advantages, it can only be used at temperatures ranging from -40°C.
The temperature is as low as +80°C, and the structure detects the presence or absence of flame by transmitting to the control circuit that its own resistance changes due to the light emitted from the flame, so it is always installed opposite to the flame as shown in Figure 2. For this reason, the temperature of the CdS itself increases due to the radiant heat from the flame, resulting in a decrease in sensitivity and service life.The burner structure becomes complicated due to heat shielding and insulation, and the combustion tube is long and large in order to keep the CdS itself away from the flame. It had drawbacks such as being difficult to form. In addition, in order to obtain good combustion conditions, measures are sometimes taken to greatly expand the outer diameter of the combustion tube, but in this case, the fuel spray at the center of the flame-holding plate usually expands at the same time as the outer diameter of the combustion tube increases. As a result, CdS becomes more susceptible to the effects of radiant heat, which has been an obstacle to improving combustion.

[Means for solving problems]

The structure of the present invention for solving the above object will be explained using FIG. 1 corresponding to the embodiment.
An outer cylinder 7 having a larger diameter than the combustion cylinder 3 is formed on the outer periphery of the combustion cylinder 3 having
A technical means in which a part of the combustion air is introduced into the auxiliary air passage 14 and supplied into the combustion tube 3 along the outer periphery of the flame detector 6. is being taught.

〔Example〕

An embodiment of the present invention will be explained based on Fig. 1.
1 is a nozzle, and 2 is a flame-holding plate, each of which is fixed inside the combustion tube 3. There is a combustion tube 3 on the outer periphery of the combustion tube 3.
A larger diameter outer cylinder 7 is arranged, and a gap between the combustion cylinder 3 and the outer cylinder 7 forms a sub-ventilation passage 14 for combustion air,
The passage is closed at part c on the tip side, and communicates with the blower 5 at parts a and b. Most of the combustion air passes through part a from the blower 5 and is directed to the nozzle 1 as shown by arrow A.
It is supplied toward the flame holding plate 2 from the rear surface of the flame holding plate 2. and,
The combustion tube 3 and the outer tube 7 each have CdS mounting holes 8.
and 9 are bored, and the CdS 6 is attached to the surface of the outer cylinder 7 and passes through the combustion cylinder 3 and the outer cylinder 7, with only its light receiving part facing into the combustion cylinder. Combustion cylinder 3
Since the diameter of the CdS mounting hole 8 is approximately 1.5 times the diameter of the CdS 6, a portion of the combustion air flows from part b along the surface of the CdS 6 as shown by arrow B from the CdS mounting hole 8 into the inside of the combustion tube 3. do. When a flame 10 is formed on the surface of the flame holding plate 2, the light generated from the flame hits the light receiving part of the CdS 6 facing the inside of the combustion tube 3, and the resistance value of the CdS 6 changes, causing the presence of flame. sense things. When combustion is performed, combustion air is supplied from the blower 5, so when combustion is performed and a flame is present, part of the combustion air is always supplied to passage b.
is supplied into the combustion cylinder through the CdS mounting hole 8.
This will cool CdS6.

[Effect of idea]

Since the present invention has the above configuration, it has the following effects.

(1) Prevents sensitivity loss due to CdS temperature rise and significantly extends component life.

(2) CdS can be placed near the flame, improving detection sensitivity, and the combustion tube can be shortened and the burner can be made smaller, making it possible to supply an inexpensive burner.

(3) Since the influence of radiant heat on CdS can be reduced, the outer diameter of the combustion tube can be increased and good combustion can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment of the present invention, FIG. 2 is a sectional view showing a conventional embodiment, and FIG. 3 is a perspective view showing a flame detector. Explanation of symbols, 1... Nozzle, 2... Flame holding plate, 3
... Combustion cylinder, 4 ... Pump, 5 ... Blower, 6 ...
...Flame detector (CdS), 7...Outer cylinder, 8...CdS mounting hole provided in the combustion tube, 9...CdS installed in the outer cylinder
Mounting hole, 10...Flame, 11...CdS mounting pedestal, 12...CdS main body casing, 13...CdS
Light receiving part, 14...Sub-air passage.

Claims (1)

[Scope of utility model registration request] An outer cylinder 7 having a larger diameter than the combustion cylinder 3 is provided on the outer periphery of the combustion cylinder 3 which has a liquid fuel spray nozzle 1 and a flame stabilizing plate 2 inside.
A sub-air passage 14 connected to the blower 5 is formed in the gap between the outer cylinder 7 and the combustion cylinder 3, and a flame detector 6 is installed from the outer cylinder 7 to the inside of the combustion cylinder 3. A liquid fuel burner characterized in that a part of air is introduced into a sub-air passage 14 and supplied into a combustion cylinder 3 along the outer periphery of a flame detector 6.