JPS648245B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improved structure of a combustion safety device, particularly one that also detects oxygen-deficient combustion with a flame rod for flame detection, which can be adapted to different types of gas without changing the position of the flame rod. With the goal.

When detecting oxygen-deficient combustion using a commonly used flame rod that utilizes flame rectification, the flame rod's mounting position must be adjusted depending on the type of gas because the shape of the flame differs depending on the type of gas. Need to change. Furthermore, the current varies depending on the slight difference in the mounting position of the flame rod, and it is difficult to obtain the same flame current at an oxygen concentration of 18%, for example, with the same specifications.

The present invention was invented in view of the above points, and will be described below with reference to FIGS. 1 and 2.

1 is a gas fan heater, exterior case 2 front plate 3
An intake hole 4 is provided in the upper part of the case 2, and a discharge hole 5 is provided in the lower part of the case 2.A line-shaped gas burner 6 is installed horizontally in the approximate center of the outer case 2, and the surroundings of this gas burner are connected to the combustion chamber wall 7. gas burner 6
A cross flow fan 8 is installed below and parallel to this. Also, the bottom wall 9 of the combustion chamber wall 7
is integrally connected to the front plate 3 of the exterior case 2, and an air supply hole 11 is bored in the lower part of the front wall 10.
An air supply passage 12 is defined in front of the combustion chamber 0, and a discharge hole 14 is formed in the top surface 13 of the combustion chamber wall 7.

Reference numeral 15 indicates a connection between the intake port 4 and the front wall 10 of the combustion chamber wall 7 to the top surface 13 of the combustion chamber wall and the top plate 16 of the exterior case 2.
Furthermore, it is a partition plate installed near the cross flow fan 8 between the rear wall 17 of the combustion chamber wall 7 and the rear plate 18 of the exterior case 2, and between this and the combustion chamber wall 7 and the exterior case 2. Air passages 19 and 20 are formed respectively.

Reference numeral 21 denotes a control circuit installed near the motor 22 for driving the cross flow fan 8, which controls the gas flow connected to the spark plug 23 attached to the tip side of the gas burner 6, the flame detection flame rod 24 attached to the rear, and the gas nozzle 25. Solenoid valve 2 installed in the passage 26
7 and 28 are each electrically controlled. That is, by performing a predetermined energization operation, the solenoid valves 27 and 28 are opened, and the spark plug 23 discharges the gas burner 6.
When the combustion engine ignites, the flame rod 24 detects this, stops the discharge of the spark plug 23, and enters steady combustion. Further, when the gas burner 6 performs oxygen-deficient combustion, this is detected by a decrease in flame current by the flame rod 24, and the solenoid valves 27 and 28 are closed.

Further, as shown in FIG. 3, the front wall 10 of the combustion chamber wall 7 is provided with a viewing window 29 at a position corresponding to the spark plug 23.
A ventilation hole 30 is formed at a position facing slightly below the hole 4. A damper 31 is installed on the front side of this vent hole 30 with screws 3 to open and close it depending on the type of gas.
It is pivoted at 2 so that it can be opened and closed freely. That is, for a gas type with a slow burning rate (for example, 13A), the vent hole 30 is completely closed by the damper 31, while for a gas with a fast burning rate (for example, 6C), the vent hole 30 is opened and air is supplied to the flame rod 24 portion. By promoting the lift of the flame, the flame formation conditions due to different gas types are made almost the same, and the oxygen concentration decreases (in most cases, 17
~18%) Sometimes obtaining the same frame current can shut off the solenoid valves 27, 28.

In addition, during steady combustion, indoor air is sucked through the intake hole 4 as the cross flow fan 8 rotates, and a portion of it is discharged into the room again from the discharge hole 5 via the ventilation path 20, and a portion of the air is sucked into the room through the ventilation path 19. Midway discharge hole 13
The exhaust gas from the gas burner 6 is mixed to form hot air, which is discharged from the discharge hole 5. Further, a part of the air flows down the air supply path 12 and is supplied to the gas burner 6 from the air supply hole 11 as combustion air.

As described above, the combustion safety device according to the present invention has a ventilation hole bored in the front wall surrounding the front of the burner, in the part facing the flame rod attached to the burner, and
It is equipped with a damper that adjusts the opening degree of this vent according to the type of gas, and in the case of a gas with a high combustion rate, air is supplied to the flame rod part through the vent to cause combustion that is close to lifting. As a result, the same flame current can be obtained for different gas types at approximately the same oxygen concentration without changing the mounting position of the flame rod, and productivity can be improved.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of a gas fan heater equipped with a combustion safety device according to the present invention, FIG. 2 is a schematic front view, and FIG. 3 is a front view of the main parts. 6... Gas burner, 7... Combustion chamber wall, 10... Front wall,
24...Frame rod, 30...Vent hole, 31...Damper.

Claims (1)

[Claims] 1 The front, back and bottom of the burner are surrounded by a combustion chamber wall, and an intake hole is provided at the bottom of this front wall, and the front of the front wall is directed downward to supply combustion air to the burner. A flame rod for flame detection is installed at an appropriate location in the front wall, and a vent hole is provided in the front wall facing the flame rod, and a damper is provided to adjust the opening degree of the vent hole depending on the type of gas. Features a combustion safety device.