JPH06229543A - Burner - Google Patents

Abstract

PURPOSE:To prevent inconvenience of extinguishing of a fire on the way due to an operation of a safety unit caused by an external cause such as silicone oil contained in a hair sprayer or impurities in fuel in a burner in which presence/absence of a flame, a decrease in oxygen concentration is detected by a flame rod. CONSTITUTION:A burner comprises a burner body 12, a cylindrical burner head 14 provided with a plurality of flame holes 17 provided at a peripheral wall 14C and supplied with mixed gas of fuel and combustion air from the body 12 to inject mixed gas at a peripheral wall 14C, and a flame rod 20, wherein the rod 20 detects presence/absence of a flame F and a decrease in oxygen concentration. The rod 20 has a circular arc- or bow-shaped flame sensor 20A disposed along the wall 14C of the head 14 so that the sensor 20A is exposed with a plurality of flames.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a combustion device mainly used for petroleum fan heaters and the like, and more particularly to a combustion device in which a flame rod detects the presence or absence of a flame and a decrease in oxygen concentration.

[0002]

2. Description of the Related Art A combustion apparatus used for this type of oil fan heater or the like takes in indoor air as combustion air and discharges combustion gas into the room. In this case, the oxygen concentration in the room decreases, oxygen deficiency occurs, incomplete combustion occurs, and the amount of carbon monoxide generated increases. Therefore, in recent years, there has been known a flame rod that detects the presence or absence of a flame and a decrease in oxygen concentration, and activates a safety device to stop combustion when the oxygen concentration falls below a reference value.

FIG. 5 shows the structure of a conventional combustion apparatus. A burner 1 is equipped with a vaporization tube 2 into which liquid fuel and combustion air are supplied, and a burner 1 which is mounted on the vaporization tube 2 and has a peripheral wall portion. A large number of flame holes 3 for ejecting a mixture of fuel and combustion air
And a frame rod 5 on the outer peripheral portion of the burner head 4, and the flame detection unit 5A bent downward at the tip end of the frame rod 5 has a plurality of It faces one of the flame holes 3. Then, the safety device detects a change in the ionic current of the flame flowing through the frame rod 5, and when the oxygen concentration decreases and the flow of the ionic current of the flame sharply decreases, the operation of the fuel supply device such as the fuel pump is activated. The burner 1 was extinguished by stopping the fire, or the alarm lamp or the buzzer was driven to generate an alarm.

[0004]

By the way, since the above-mentioned combustion apparatus, for example, the oil fan heater, takes in the air in the room as combustion air and burns it, silicon oil is removed during the heating operation of the oil fan heater. When the contained hair spray is frequently used, silicone oil is scattered in the room and evaporates, and the evaporated silicone oil is mixed with the combustion air supplied to the burner 1, and the silicone oil is vaporized. It will be mixed with vaporized fuel inside the cylinder 2 and will be ejected from the flame holes 3 of the burner head 4.

During combustion, silicic acid (SiO ₂ ) is produced from the silicone oil, and this silicic acid combines with the oxide film (alumina) on the surface of the flame detecting section 5 A facing the flame hole 3, Accumulates on the surface of the flame detection unit 5A. Moreover, since the flame detecting portion 5A of the frame rod 5 is set to have a short dimension corresponding to a part of the plurality of flames formed on the burner head 4, the surface of the portion exposed to the flame is short-term. In between, it will be covered by the insulating material silicic acid. Therefore, when a hair spray containing silicone oil is frequently used, the resistance value of the flame rod 5 increases in a short period of time, the flow of the ionic current of the flame decreases, and the oxygen concentration decreases so much. There was a problem that the safety device worked though not.

The present invention has been made in view of the above-mentioned circumstances, and in a combustion device in which the presence or absence of a flame and a decrease in oxygen concentration are detected by a flame rod, external factors such as silicone oil contained in hair spray are used. The purpose is to prevent the inconvenience of fire extinguishing on the way due to the impurities in the fuel and fuel, which can be extinguished for a long time.

[0007]

According to the present invention, a burner body and a cylindrical shape in which a mixture of fuel and combustion air is supplied from the burner body and a plurality of flame holes for ejecting the mixture are provided in a peripheral wall. A burner head and a frame rod, in a combustion device that detects the presence or absence of flame and a decrease in oxygen concentration with this frame rod, the frame rod is an arc shape arranged along the peripheral wall of the burner head, Alternatively, it has a bow-shaped flame detection unit, and the flame detection unit is exposed to a plurality of flames.

[0008]

As described above, since the frame rod has the arc-shaped or bow-shaped flame detection portion arranged along the peripheral wall of the burner head, the portion exposed to the flame is much longer than the conventional one. Can be taken, for example, silicic acid (Si
It takes a long time for the insulating material such as O ₂ ) to cover the surface of the flame detecting portion. Therefore, due to external factors such as silicone oil contained in hair spray and impurities in the fuel, the resistance value of the frame rod increases, and the safety device operates unnecessarily to extinguish fire halfway. Can be suppressed over.

Further, since the flame detection section is exposed to a plurality of flames, a large ion current of the flame can be obtained, and highly accurate and stable flame detection can be performed.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the plan views of FIGS. In FIG. 1, reference numeral 10 denotes a burner. The burner 10 has a bottomed cylindrical vaporization cylinder 12 (burner main body) in which an electric heater 11 such as a sheath heater is embedded in a peripheral wall, and an upper portion of the vaporization cylinder 12. Aperture plate 1
3, a cylindrical burner head 14 fitted and attached to the upper end opening of the vaporizing cylinder 12 on the diaphragm plate 13, and a horizontal portion fixed to the upper end of the vaporizing cylinder 12, and on the outer circumference of the peripheral wall of the burner head 14. The burner head 14 is composed of a heat-resistant steel burner ring 15 and a cover plate 14 at the top.
In addition to having A, the bottom wall 14B has a large number of through holes 16,
16 is provided, and a large number of flame holes 17, 17 are provided side by side over substantially the entire circumference of the peripheral wall 14C.

The burner ring 15 has a standing wall 15A facing the peripheral wall 14C of the burner head 14, and the standing wall 15A has a large number of vertical slits extending from the intermediate height position of the standing wall 15A to the upper edge thereof. 18, 18 are provided.

Reference numeral 19 denotes a bottomed cylindrical burner case which is provided on the outer circumference of the vaporization cylinder 12 and accommodates and fixes the vaporization cylinder 12 therein.
In A, an insulator 21 that supports the frame rod 20 and an insulator 23 that supports the ignition rod 22 are fixedly supported. Reference numeral 24 is a primary air passage for sending the primary air for combustion from the blower 25 into the vaporization cylinder 12, and 26 is the vaporization cylinder 12.
A secondary air passage for sending the secondary air for combustion from the blower 25 into the space between the burner case 19 and the burner case 19.

Reference numeral 27 denotes a fuel nozzle which is provided concentrically with the primary air passage 24 and has its tip end facing the inside of the vaporization cylinder 12, and the fuel nozzle 27 is fed by a fuel pump 28 such as an electromagnetic pump. The liquid fuel (kerosene) is jetted and supplied into the vaporization cylinder 12.

The frame rod 20 has a diameter of about 2.9 m.
m, is made of an iron-chromium refractory metal material (FCHW) containing about 4.5 to 6% of aluminum, and its tip extends along the peripheral wall 14C of the burner head 14 over approximately half the circumference of the peripheral wall 14C. A flame detection unit 20A is disposed and bent in an arc shape that is substantially concentric with the peripheral wall 14C of the burner head 14, and the flame detection unit 20A is formed with a plurality of flames formed in a plurality of flame holes 17, 17. It is exposed to F, F. In addition, the flame detection unit 20
The tip portion of A and a proper place on the way are held by a plurality of heat resistant insulating supports 29, 29 attached to the vertical slits 18, 18 of the standing wall 15A of the burner ring 15.

As shown in FIG. 4, the heat-resistant insulating support 29 is provided with a support groove 30 for inserting the flame detecting portion 20A of the frame rod 20 in the front, and in the rear, both of the vertical slits 18 are formed. A pair of engagement grooves 31, 31 for engaging the edge portions are formed.

In the above structure, when the vaporization cylinder 12 is heated to the vaporizable temperature of the liquid fuel by energizing the electric heater 11, the blower 25 and the fuel pump 28 are operated, the liquid fuel is discharged from the fuel nozzle 27, and the primary fuel is discharged. From the air passage 24, the primary air for combustion taken from the room is supplied into the vaporization cylinder 12. Here, the liquid fuel supplied to the inside of the vaporization cylinder 12 is vaporized by contacting the vaporization surface, and the mixture of the vaporized fuel and the primary air for combustion is passed through the passage of the throttle plate 13 and the through holes 16, 16. It is supplied into the burner head 14 through the nozzles and is ejected from the flame holes 17, 17. The jetted air-fuel mixture is ignited by spark discharge generated between the tip of the ignition rod 22 and the burner head 14 to start combustion, and the flame F directed to the flame holes 17 and 17 laterally or obliquely upward. , F are formed, and at this time, the flame detection portion 20A of the frame rod 20 arranged along the peripheral wall 14C of the burner head 14 over substantially half the circumference of the peripheral wall 14C has the flame hole 1
It is exposed to a plurality of flames F, F formed on Nos. 7 and 17.

Thus, the flame ion current flows through the frame rod 20, and the presence or absence of the flame F and the decrease in oxygen concentration are detected by this ion current flow. And the safety device
When the change in the ion current of the flame flowing through the flame rod 20 is detected, and when the oxygen concentration decreases and the flow of the ion current of the flame sharply decreases, the operation of the fuel pump 28 is stopped to extinguish the burner 10, Drives an alarm lamp or buzzer to generate an alarm.

According to the present embodiment, the frame rod 20 has the peripheral wall 1 along the peripheral wall 14C of the burner head 14.
An arc-shaped flame detection unit 20 arranged over approximately half of 4C.
Since A is provided, the portion exposed to the flame F can be made much longer than in the conventional case. Therefore, silicic acid (SiO ₂ ) generated from silicon oil during combustion
Insulating material such as etc. covers the surface of the flame detection unit 20A,
As a result, it takes a long time for the safety device to operate.As in the past, due to external factors such as silicone oil contained in hair spray and impurities in the fuel, the flame rod's The inconvenience that the resistance value increases and the safety device operates unnecessarily to extinguish the fire on the way can be prevented for a long period of time.

Further, the flame detector 20A has a plurality of flames F, F.
Since it is exposed to, the ion current of the flame can be made large, and the flame detection accuracy is usually high, and extremely stable flame detection can be performed.

Further, in the above-mentioned embodiment, a plurality of heat resistances in which the leading end portion and the middle portion of the flame detecting portion 20A formed in an arc shape are attached to the vertical slits 18 of the standing wall 15A of the burner ring 15 are provided. Since it is held by the insulating supports 29, 29, even though the length dimension of the flame detecting portion 20A is set to be significantly longer than in the conventional case, thermal deformation of the flame detecting portion 20A can be suppressed, and the flame F It is possible to prevent such an inconvenience that the detection position of is changed and the accuracy of flame detection is lowered.

In the above-described embodiment, the flame detecting portion 20A has an arc shape, but it may have an arc shape.
Although the liquid fuel combustion device has been described, it may be a gas combustion device.

[0022]

As is apparent from the above description, the present invention has the following advantages.
In a combustion device that detects the presence or absence of flames and a decrease in oxygen concentration with a flame rod, a safety device works due to external factors such as silicone oil contained in hair spray and impurities in the fuel It is possible to provide a combustion device that can suppress the inconvenience caused over a long period of time, has high reliability, and is excellent in safety. Further, since the flame detection unit is exposed to a plurality of flames, a large ionic current of the flame can be obtained, and highly accurate and stable flame detection can be performed.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing the overall configuration of a combustion apparatus according to an embodiment of the present invention.

FIG. 2 is a plan view of the main part of the same.

FIG. 3 is a perspective view of a frame rod of the same.

FIG. 4 is a perspective view of the heat-resistant insulating support tool.

FIG. 5 is a cross-sectional view showing the overall configuration of a conventional combustion device.

[Explanation of symbols]

 12 vaporization cylinder (burner main body) 14 burner head 14C peripheral wall of burner head 17 flame hole 20 frame rod 20A flame detector F flame

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Osamu Tsunoda 2-18 Keihan Hondori, Moriguchi City, Osaka Sanyo Electric Co., Ltd.

Claims (1)

[Claims] 1. A burner main body, a cylindrical burner head having a peripheral wall provided with a plurality of flame holes for supplying a mixture of fuel and combustion air from the burner main body, and a frame rod. In the combustion device, which is configured to detect the presence or absence of flame and a decrease in oxygen concentration with this flame rod, the flame rod has an arc-shaped or arc-shaped flame detection portion arranged along the peripheral wall of the burner head. A combustion device, characterized in that the flame detector is exposed to a plurality of flames.