JPH10300093A - Safety device for lack of oxygen in combustion device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make a stable operation of a safety device for a lack of oxygen in a combustion device. SOLUTION: There is provided a thermocouple 19 for sensing a temperature of a flame (f) at a pilot burner 17 for use in igniting a main burner 10 and the thermocouple 19 is connected to a gas safety valve 12a to detect a temperature of the flame (f) when the flame (f) is lifted up due to a lack of oxygen in indoor air and then the gas safety valve 12a is closed. A draft restricting part 6b1 or a draft controlling part 6b2 having a large area with an air opening 6a being not opened is arranged below the flame (f) at a bottom plate 6 of a case of a combustion device. In the case that a concentration of oxygen in an indoor area is a concentration value in which the safety device for lack of oxygen is not tried to be operated, the flame (f) is prevented from becoming a lift flame f1 under a flow force of draft air (g). A plurality of different kinds of bottom plates 6 having a different area of the draft restricting part 6b1 or 6b2 are prepared and they are separately used in compliance with a lifting characteristic of the type of gas used.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a combustor such as a stove or a water heater using gas as a fuel, and more particularly to a gas burner for stopping gas when the air in a room in which the combustor is installed becomes oxygen-deficient. The present invention relates to an oxygen deficiency safety device for a combustor.

[0002]

2. Description of the Related Art Conventionally, there is known an oxygen-deficient safety device which detects whether or not air in a room in which a combustor is installed is in an oxygen-deficient state and stops the gas when the air is depleted. An example of the apparatus is disclosed in Japanese Utility Model Laid-Open No. 2-36745. The device is provided with a normal-fire oxygen deficiency detection burner and a thermocouple opposed thereto in a case of a combustor, and when the output of the thermocouple changes, closes a gas safety valve of a main burner, In order to prevent the output of the thermocouple from being disturbed due to the wind of the flame of the oxygen deficiency detection burner being shaken by the wind, the oxygen deficiency detection burner is covered with a cover.

[0003] When the air in the room in which the combustor is installed becomes oxygen-deficient, the flame of the oxygen-deficiency detection burner extends and finally lifts up as an oxygen-deficient flame, and the temperature and output detected by the thermocouple in accordance with this state change. This causes the gas relief valve to close.

However, the lift state differs depending on the gas type, and the oxygen concentration at which the gas safety valve operates also differs depending on the gas type. In addition, if the size of the cover for preventing the sway of the flame of the burnout sensor is not appropriate, the gas safety valve may not operate even at the same oxygen concentration.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to enable the oxygen-deficient safety device of a combustor to operate properly and to make the device at low cost.

[0006]

According to a first aspect of the present invention, there is provided a case in which an exhaust outlet is provided at an upper portion and a main burner is mounted inside, and a case is provided below the main burner. In the oxygen deficiency safety device for a combustor, comprising: an oxygen deficiency detection burner, a flame detection element for detecting the flame of the oxygen deficiency detection burner, and a gas safety valve operated by the output of the flame detection element. A draft suppression portion that does not make a hole is provided at a position below the flame opening of the oxygen deficiency detection burner on the bottom plate to be attached, and a large number of air holes are entirely provided at positions other than the draft suppression portion of the bottom plate, and the draft suppression portion is provided. Is characterized in that the width is set wide when the lift of the gas used is large and narrow when the lift is small.

According to this means, foreign matter can be prevented from entering the case from the bottom with the bottom plate, and if the bottom plate having a draft suppression portion having a width suitable for the type of gas is attached to the case, acid can be obtained. The flame of the missing detection burner is not fluctuated by the draft air, and the lack of oxygen state can be detected properly.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment in which the present invention is applied to a wall-mounted gas stove will be described with reference to the drawings. 1 and 2, reference numeral 1 denotes a wall-mounted gas stove as a combustor, 2 denotes a case thereof, and the case 2 comprises a front plate 3, an upper plate 4, a rear plate 5, and a bottom plate 6, which are connected to each other. An exhaust outlet 7 is provided above the face plate 3. FIG. 3 (A)
As shown in (B), there are two types having a large number of air holes 6a and draft suppression portions 6b1 or 6b2 having different areas.
The bottom plate 61 having the draft suppression portion 6b1 having a small area is
Bottom plate 6 having a draft suppressing portion 6b2 having a large area, which is used for a gas having a small lift property, for example, 13A gas.
2 is used in the case of a gas having a high lift property, for example, LPG.

Vertical beams 8 and 9 are fixed to both sides of the inside of the rear plate 5, and a main burner 10 is fixed below the vertical beams 8 and 9, and a pilot burner is attached to the lower front part of the main burner 10. The plate 11 is fixed. A gas source valve 12 having a gas safety valve 12a provided therein is attached to an outer surface of one of the vertical beams 9, and a gas inlet pipe 13, a main gas pipe 14, and a pilot gas pipe 15 are connected to the gas source valve 12. A gas hose connection pipe 16 is connected to the inlet of the gas inflow pipe 13a, a tip of the main gas pipe 14 is connected to the main burner 10, and a tip of the pilot gas pipe 15 is connected to a pilot burner 17 for igniting the main burner 10. Connected. The pilot burner 17 is an oxygen deficiency detection burner. The pilot burner 17, the spark plug 18, and the thermocouple 19
Is fixed to the pilot burner mounting plate 11 via the set plate 20.

The thermocouple 19 functions as a flame detecting element for detecting the temperature of the flame of the pilot burner 17, and its lead wire 19 a is connected to the gas safety valve 12. The output of the thermocouple 19 may be input to a control circuit (not shown), and the control circuit may control the gas safety valve 12a.

In this embodiment, the pilot burner 17 for igniting the main burner 10 is used as an oxygen deficiency detection burner. However, another small burner may be attached and used.

Reference numeral 22a denotes a front exhaust guide plate provided at a front portion inside the case 2, 22b denotes a rear exhaust guide plate provided at a rear portion inside the case 2, and 23 denotes a fixture for the gas inflow pipe 13. Adjusting shaft 2 engaged with valve shaft 12b of gas source valve 12
4 is provided penetrating the upper plate 4, and the knob 24a is attached to this.

A spark discharge from the spark plug 18 ignites the pilot burner 17, and the main burner 10 is ignited by the flame of the pilot burner 17 to burn the main burner 10. As a result, a draft is generated and the bottom plate 6 The air in the room is supplied to the front exhaust guide plate 22a and the rear exhaust guide plate 22a from the air holes 6a provided uniformly over the entire surface at positions other than the draft suppression portion.
b, a part of which flows into the combustion air of the main burner 10, and the remainder is discharged from the exhaust outlet 7 together with the exhaust. At this time, as shown in FIG. 4, even if the draft air g due to the combustion of the main burner 10 flows through the air hole 6a, the bottom plate 6
Since the draft suppressing portion 6b1 or 6b2 does not allow the draft air g to pass through, the flame f burns in a stable state without being affected by the flow of the draft air g, and the flame f and the thermocouple 19 have a fixed relationship. Keep. However, when the indoor air becomes oxygen-deficient, the flame f becomes a lift flame f1 due to lack of oxygen and separates from the thermocouple 19, and the thermocouple 19
Is detected, the gas safety valve 12a is closed and the main burner 10 and the pilot burner 17 are extinguished.

The area of the draft suppressing portion 6b1 or 6b2 is small if the gas lift is small, and wide if the gas lift is large. For example, when the gas type is 13A, the bottom plate 61 having the narrow draft suppressing portion 6b1 is reduced. Use, LP
In the case of G, a bottom plate 62 having a wide draft suppression portion 6b2 is used. As described above, the bottom plate 62 having a large area of the draft suppressing portion is used for LPG or the like having a large lift property.
Draft action on the pilot burner 17 as an oxygen deficiency detection burner is small, and the gas safety valve 12a does not break prematurely. On the other hand, in the case of 13A with small liftability, the bottom plate 61 having a small area of the draft suppressing portion is used, so that the draft action on the pilot burner 17 is large and the gas safety valve 12a is not delayed.

FIG. 5 shows a reference example.
Is provided behind the main burner 10 between the pilot burner mounting plate 11 and the wind shield plate 25 so that the draft air g does not directly contact the flame f. If so, the cooling of the flame is delayed, so that harmful NO2 is hardly emitted.

[0016]

As described above, according to the first aspect of the present invention, the flame of the oxygen deficiency detection burner fluctuates due to the draft air by attaching the bottom plate having the draft suppression portion having a width adapted to the gas type to the case. However, there is an effect that the gas safety valve can be operated properly. Further, the bottom plate can prevent foreign matter from entering the case.

[Brief description of the drawings]

FIG. 1 is a front view showing an embodiment of the present invention.

FIG. 2 is also a longitudinal side view

FIG. 3 is a plan view of two types of bottom plates.

FIG. 4 is a front view of a main part.

FIG. 5 is a side view of a reference example.

[Explanation of symbols]

2 Case 6, 61, 62 Bottom plate 6a Air hole 6b1, 6b2 Draft suppression unit 10 Main burner 12 Gas main valve 12a Gas safety valve 17 Oxygen deficiency detection burner 19 Thermocouple

Claims (1)

[Claims] 1. A case having an exhaust outlet at an upper portion and having a main burner mounted therein, an oxygen deficiency detection burner provided below the main burner, a flame detection element for detecting a flame of the oxygen deficiency detection burner, An oxygen deficiency safety device for a combustor, comprising: a gas safety valve operated by an output of the flame detection element, wherein a draft is prevented from being formed in a bottom plate attached to a bottom of the case below a flame opening of the oxygen deficiency detection burner. A large number of air holes are provided in the bottom plate at positions other than the draft suppression portion, and the width of the draft suppression portion is set to be wide when the liftability of the gas to be used is large, and to be narrow when the gas liftability is small. An oxygen-deficient safety device for a combustor, characterized in that: