JPH05180436A - Combustion device - Google Patents

Abstract

PURPOSE:To prevent Bunsen combustion from occurring at the initial time of ignition and to perform a positive two-stage combustion. CONSTITUTION:A primary flame port 3 is covered by a container 5 forming a primary combustion chamber 4, a secondary flame port 6 is arranged at the upper part of the container to form a combustion pipe, a temperature sensor 7 is arranged at a proper location in the combustion pipe, the temperature sensor 7 is cooperatively related with a fan for supplying combustion air and they are controlled in such a way that the number of rotation of the fan is increased when the temperature of the combustion pipe is less than the specified temperature. At the time of initial ignition, the temperature of the combustion pipe is low, so that the Bunsen combustion may easily occur. This state is detected by the temperature sensor, the number of rotation of the fan is increased to increase the combustion speed, the primary flame is stabilized and even under the initial ignition, the positive two-stage combustion is carried out to accomplish the low NOx formation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a combustion device designed to reduce NOx.

[0002]

2. Description of the Related Art As a conventional combustion apparatus designed to reduce NOx, for example, as shown in Japanese Patent Publication No. 62-39329, a primary flame hole portion having a primary flame hole or a burner body. Is covered with a container forming a primary combustion chamber, and a secondary flame port having a single opening is provided on the upper surface of the container to perform a two-stage combustion bar in which primary combustion and secondary combustion are performed separately. There is na.

Such a two-stage combustion burner is separated into a primary flame and a secondary flame, and the maximum temperature and average temperature of the flame are lowered, so that the generation of NOx can be reduced.

[0004]

However, in such a conventional two-stage combustion type combustion apparatus, the temperature of the combustion tube is different between the case of initial ignition and the case of reignition.
At the time of initial ignition, the combustion speed is slow because the temperature of the air-fuel mixture in the vessel forming the combustion tube is low, and the primary flame is not formed because the flame is not held in the primary flame hole. However, there was a problem that the Bunsen combustion state, in which only a flame was formed, was likely to occur.

The present invention is directed to a combustion apparatus that detects the temperature of the combustion tube and changes the fan speed at the time of initial ignition to control the combustion speed so as to ensure a two-stage combustion even at the time of initial ignition. It is intended to be provided.

[0006]

In order to achieve the above object, the present invention has the following constitution.

That is, the primary flame hole portion having the primary flame hole is set to 1
While covering with a container that forms the next combustion chamber, a secondary flame port is provided on the upper part of this container to form a combustion pipe, and a temperature detector that detects the temperature of the combustion pipe is provided at an appropriate position of the combustion pipe. The reactor is associated with a fan that supplies combustion air, and is controlled to increase the fan rotation speed when the temperature of the combustion tube is below a certain temperature.

[0008]

[Operation] Since the temperature of the combustion tube is low at the initial ignition, the temperature is detected by the temperature detector, the fan speed is increased to increase the air amount, and the inside of the container is brought close to the theoretical air amount, and the combustion speed of the air-fuel mixture is increased. So that the primary flame is held in the primary flame hole. Then, after the temperature of the combustion tube becomes high and the Bunsen combustion does not occur, the fan speed is returned to an appropriate speed corresponding to the combustion amount.

[0009]

1 is a perspective view showing an embodiment of the present invention, FIG.
1 is a cross-sectional view of a main part, and 1 is a primary flame hole portion 3 having a primary flame hole 2 covered with a container 5 forming a primary combustion chamber 4,
It is a combustion tube formed by providing a secondary flame port 6 on the upper part of this container 5. Reference numeral 7 is a temperature detector provided at an appropriate position of the container 5 forming the combustion pipe 1, and is associated with a fan (not shown) for supplying combustion air. Control to make it higher. 8 is a mixing part.

Next, the control operation of this combustion apparatus will be described with reference to the flow chart of FIG.
Explain by chart. At the time of ignition, first, at step 10, the temperature detector 7 detects the temperature of the combustion tube, and if the temperature is equal to or higher than a certain temperature, the process proceeds to step 11, and the fan is normally ignited and burned by controlling the rotation speed for normal ignition. .. If the combustion tube temperature is below a certain temperature in step 10, the process proceeds to step 12 to increase the fan rotation speed to increase the air amount more than in the steady state, and to bring the air amount in the container 5 closer to the theoretical air amount. The primary flame and the primary flame hole 2
Hold it to control so that the two-stage combustion is normally performed, and normally ignite and burn. After a certain period of time, the fan is returned to the proper rotation speed corresponding to the combustion amount.

Normally, in the two-stage combustion burner, the inside of the container 5 is burned in a state of less than the theoretical air amount, and the unburned portion is burned at the secondary flame port 6, so that the primary flame is stabilized. The sex is low. When the air-fuel ratio in the container 5 is determined so that the primary flame is held in the primary flame hole 2 while the temperature of the container 5 rises due to combustion, the air-fuel ratio in the container 5 during cold start is determined. Since the combustion speed is low, the primary flame does not hold in the primary flame hole 2, resulting in Bunsen combustion. Therefore, during this cold start, the air amount is increased more than in the steady state, and the combustion speed is increased by approaching the theoretical air amount so that the primary flame holes 2 are held.

[0012]

As described above, the present invention detects the temperature of the combustion tube and increases the fan rotation speed when the temperature of the combustion tube is low.
Since the subsequent flame is stably formed to prevent the Bunsen combustion, the two-stage combustion is surely performed even during the initial ignition, and the NOx reduction can be achieved.

[Brief description of drawings]

FIG. 1 is a perspective view of a combustion apparatus showing an embodiment of the present invention.

FIG. 2 is a cross-sectional view of the main parts of the combustion device of the present invention.

FIG. 3 is a flowchart showing a control operation.

[Explanation of symbols]

 1 Combustion device 2 Primary flame hole 3 Primary flame hole part 4 Primary combustion chamber 5 Container 6 Secondary flame port 7 Temperature detector

Front page continuation (72) Inventor Satoshi Kawaguchi, Noritsu Co., Ltd., 32 Akashi-cho, Chuo-ku, Kobe-shi, Hyogo Prefecture (72) Inventor Hideo Ueda 32 Akashi-cho, Chuo-ku, Kobe, Hyogo, Ltd.

Claims (1)

[Claims] 1. A primary flame hole portion having a primary flame hole is covered with a container forming a primary combustion chamber, and 2 is provided on the upper part of this container.
A combustion pipe is formed by providing a secondary flame port, and a temperature detector for detecting the temperature of the combustion pipe is provided at an appropriate position of the combustion pipe, and the temperature detector is associated with a fan that supplies combustion air at the time of ignition. When the temperature is below a certain temperature, the combustion device is controlled to increase the fan rotation speed.