JPH1061944A - Mounting structure for ultraviolet flame detector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mounting structure for an ultraviolet flame detector for using the same at a temperature not higher than the heat resistant temperature thereof. SOLUTION: A through hole 7 is provided on the side wall 6 of a heating facility and a flame monitor pipe 2, provided with a nut 11 having a peep window 10 consisting of an ultraviolet transmitting member and screwed to a screw unit formed at the outer end unit 9, is attached to the through hole 7 while a heat insulating case 4, in which an ultraviolet flame detector 3 is mounted, is attached to the flame monitor pipe 2 so that the ultraviolet flame detector 3 is opposed to the nut 11, attached to the flame monitor pipe 2, with a predetermined space.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mounting structure for an ultraviolet flame detector used as a safety device for heating equipment.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 3, an ultraviolet flame detector 30 has been used as a safety device in a heating facility. The ultraviolet flame detector 30 includes a through hole 32 formed in a side wall 31 of a heating facility (furnace wall of a heating furnace or the like).
It is connected to the outer end of a flame monitoring pipe 33 attached to the sensor, detects ultraviolet rays of the flame through the flame monitoring pipe 33, and outputs a predetermined signal to a control device of the heating equipment when there is an abnormality in the flame. It has become.

The above-mentioned flame detector 30 must be installed near a flame-generating device such as a burner. The flame detector 30 has a heat-resistant temperature of about 100 ° C., but is higher than the heat-resistant temperature. Often it is necessary to use under conditions. Therefore, the flame monitoring pipe 3
3 to cool the flame detector 30 by supplying cooling air,
By covering with a heat insulating cover 34, the temperature rise is prevented.

[0004]

However, the cooling air is supplied to the flame monitoring pipe 33 or the flame detector 30 is used.
Even if the structure is covered with a heat-insulating cover 34, as long as the flame detector 30 is directly connected to the flame monitoring pipe 33, the heat of the heating equipment is directly transmitted from the flame monitoring pipe 33 to the flame detector 30, It is difficult to keep the flame detector 30 below its heat resistant temperature. Therefore, the flame detector 3
0 deteriorated early due to conduction heat from the flame monitoring pipe 33 and needed to be replaced frequently.

SUMMARY OF THE INVENTION In view of the above problems, an object of the present invention is to provide a mounting structure for an ultraviolet flame detector for using the ultraviolet flame detector at a temperature lower than a heat-resistant temperature.

[0006]

In order to achieve the above object, in the mounting structure of the ultraviolet flame detector according to the present invention, a through hole is provided in the side wall of the heating equipment, and the outer end portion of the through hole is transparent to ultraviolet light. Attach the flame monitoring pipe closed with the member, and install the flame monitoring pipe such that the ultraviolet flame detector faces the outer end of the flame monitoring pipe at a predetermined interval with the heat insulation case with the ultraviolet flame detector installed inside. It is characterized by being attached to.

Further, a cooling air supply device may be attached to the heat insulating case.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A mounting structure of an ultraviolet flame detector according to the present invention will be described below with reference to FIGS. The ultraviolet flame detector mounting structure 1 is composed of a flame monitoring pipe 2 and a heat insulating case 4 in which an ultraviolet flame detector 3 (hereinafter abbreviated as flame detector 3) is mounted. .

The flame monitoring pipe 2 is attached to a through hole 7 formed in a side wall 6 near a burner (not shown) of the heating equipment, and a screw portion is formed at an outer end 9 thereof.
A nut 11 having a viewing window 10 made of quartz glass, which is an ultraviolet transmitting member, is screwed into this screw portion to close the outer end 9. The viewing window 10 is not limited to quartz glass as long as it transmits ultraviolet rays and has excellent heat resistance.

The heat-insulating case 4 has flanges 14 and 15 attached to the openings at both ends of a main body 13 made of a cylindrical body to prevent light from entering the inside of the main body 13. And
A flame monitoring pipe mounting portion 16 is provided at the center of one flange 14. The flame detector 3 is attached to the inside of the heat insulating case 4 by a support plate 18. As shown in FIG. 2, the support plates 18 are attached to the outer periphery of the flame detector 3 at, for example, three places at equal intervals. The support plate 18 uses a thin steel plate in order to reduce conduction heat. The cable 21 of the flame detector 3 is a flange 1
5 is connected to a burner control device (not shown) outside the heat insulating case 4 through a hole 22 formed in the heat insulating case 4.

The heat insulating case 4 is fixed by inserting the flame monitoring pipe mounting portion 16 into the flame monitoring pipe 2. At this time, the flame monitoring pipe 2 is inserted into the heat insulating case 4 to a position where the nut 11 faces the detection unit 19 of the flame detector 3 at a predetermined interval. The above-mentioned predetermined interval refers to a distance at which the ultraviolet ray transmitted through the viewing window 10 can be detected by the flame detector 3, and is set to, for example, about 10 mm.

An air supply pipe 17 for supplying cooling air from a cooling air supply device (not shown) is attached to the upper part of the heat insulating case 4, and a discharge hole 20 is provided at the lower part.
Are formed.

In the mounting structure 1 of the ultraviolet flame detector having the above configuration, the ultraviolet light emitted from the flame of the burner passes through the observation window 10 through the flame monitoring pipe 2 and is detected by the flame detector 3. Thereby, the flame detector 3
Detects the state of the flame and outputs a control signal to the burner control device. As described above, since the heat insulating case 4 is shielded from light, malfunction does not occur even if there is an external object that generates ultraviolet rays such as sparks of arc welding or flames of a burner.

As described above, since the outer end 9 of the flame monitoring pipe 2 is closed by the viewing window 10, the hot air inside the heating equipment blows out from the outer end 9 and strikes the flame detector 3. And the flame detector 3 is attached to the heat insulating case 4 in a non-contact state with the flame monitoring pipe 2.
No heat is transmitted from the monitoring pipe 2 to the flame detector 3, and the flame detector 3 does not exceed its heat-resistant temperature (100 ° C.).

When the flame detector 3 is mounted in an environment where the flame detector 3 is exposed to high temperatures, cooling air may be supplied to the heat insulating case 4 as shown in FIG.

[0016]

As is clear from the above description, in the mounting structure of the ultraviolet flame detector according to the present invention, only the ultraviolet rays of the flame pass through the flame monitoring pipe and are detected by the ultraviolet flame detector. At this time, since the outer end of the pipe and the ultraviolet flame detector are shielded from light by the heat insulating case, malfunction does not occur even if there is equipment for generating ultraviolet light outside.
Also, the hot air inside the heating equipment does not hit the ultraviolet flame detector, and the pipe and the ultraviolet flame detector are not in contact with each other, so that the heat of the heating equipment is not transmitted to the flame detector. For this reason, the ultraviolet flame detector can be used at a temperature lower than the heat-resistant temperature, and deterioration due to heat is prevented, so that the frequency of replacing the flame detector can be reduced.

It should be noted that an ultraviolet flame detector could not be used for a burner whose ambient temperature is high, such as a regenerative burner. Has made its use possible.

Further, if cooling air is supplied to the heat insulating case, deterioration of the ultraviolet flame detector due to heat can be more effectively prevented.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view showing a mounting structure of an ultraviolet flame detector according to the present invention.

FIG. 2 is a sectional view taken along line II-II of FIG.

FIG. 3 is a partial cross-sectional view illustrating a mounting structure of a conventional ultraviolet flame detector.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Mounting structure of ultraviolet flame detector, 2 ... Flame monitoring pipe, 3 ... Ultraviolet flame detector, 4 ... Heat insulation case, 6
... side wall of heating equipment, 7 ... through hole, 9 ... outer end, 10 ... viewing window, 11 ... nut.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Futhiko Nakagawa 1-chome, Mizushima-Kawasaki-dori, Kurashiki-shi, Okayama Pref. (72) Inside Mizushima Works, Kawasaki Steel Corp. 1-chome (without address) Inside Kawasaki Steel Corporation Mizushima Works

Claims (2)

[Claims] 1. A heat-insulating case having a through-hole provided in a side wall of a heating facility, a flame monitoring pipe whose outer end is closed with an ultraviolet-transmitting member, and an ultraviolet-ray flame detector mounted inside the through-hole. An ultraviolet flame detector mounting structure, wherein the flame detector is attached to the flame monitoring pipe such that the flame detector faces the outer end of the flame monitoring pipe at a predetermined interval. 2. The mounting structure for an ultraviolet flame detector according to claim 1, wherein a cooling air supply device is mounted on the heat insulating case.