JPH04320716A - Liquid fuel burner - Google Patents

Abstract

PURPOSE:To obtain a stable flame electric current and, at the same time, prevent the generation of cracks in a burner head made of ceramics due to thermal shock. CONSTITUTION:If the bleeder 4' of a flow straightening plate 3 right below the flame detection section 9 of a flame detector is made larger than the other bleeder 4, the flame right below the flame detection section 9 becomes larger than the other flame. Since this holds even when the length of the flame becomes shorter during weak combustion, the flame detection section 9 in the flame detector is always in the combustion flame and a stable flame electric current can be obtained.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid fuel combustion apparatus having a burner head made of ceramics.

0002

[Prior Art] This type of liquid fuel combustion apparatus includes a vaporizer, a rectifier plate having a large number of vents for rectifying a gas mixture of fuel vaporized by the vaporizer and combustion air, and It is equipped with a burner head having a large number of flame ports that eject the mixed gas that has passed therethrough, and a flame detection device in which a flame detection section is provided on the burner head. The flame detection device described above has a metal rod (flame rod) placed so that it touches the center of the flame, and if a voltage is applied between these rods, the flame can conduct electricity and current can flow through the circuit, but the flame does not This method utilizes the property that current stops flowing when the sensor is turned off, and is known as the flame sensor method.

[0003] If the burner head is made of ceramic, which has excellent heat resistance, it becomes difficult to obtain a stable flame current because ceramic is electrically insulating. Therefore, in Japanese Utility Model Publication No. 60-2425, a ceramic burner head is installed inside the heat recovery wall provided in the vaporizer.
Among the many flame holes drilled in the burner head, the diameter of the flame holes on the periphery of the burner head is made larger than the others to obtain a strong and high flame. A configuration is disclosed in which a flame detector is located.

0004

[Problems to be Solved by the Invention] As mentioned above, in order to bring the flame detection part of the flame detection device into contact with the center of the flame, the diameter of the flame opening at the periphery of the ceramic burner head is made larger than that of others. Alternatively, making only the diameter of the flame opening directly below the flame detection part larger than others would require complicated processing on the ceramics, and would be difficult in terms of durability as it would be more likely to crack due to heat shock. .

The present invention provides a liquid fuel combustion system that can obtain a stable flame current even during weak combustion and improve the reliability of flame detection without providing a flame port of a ceramic burner head with any size. The purpose is to provide equipment.

[0006]

[Means for Solving the Problems] A liquid fuel combustion device according to the present invention includes a vaporizer and a rectifier plate having a large number of vents for rectifying a gas mixture of fuel vaporized by the vaporizer and combustion air. and a ceramic burner head having a large number of flame ports that eject the mixed gas that has passed through the current plate;
A flame detection device equipped with a flame detection section is installed above the burner head, and by making the vent of the rectifying plate that corresponds to the flame detection section of this flame detection device larger than the other vents, the above-mentioned result can be achieved. Achieved the purpose.

[0007]

[Operation] The mixed gas of fuel and combustion air vaporized in the vaporizer is passed through the many vents of the rectifier plate to be rectified, and then ejected from the many flame ports of the burner head to be combusted. At that time, the ventilation hole of the current plate that corresponds to the flame detection part of the flame detection device is larger than other ventilation holes, so even if it is a burner head flame, the flame directly under the flame detection part is larger than other flames. growing. This is true even during weak combustion, where the length of the flame becomes shorter. Therefore, the flame detection section of the flame detection device is always in the combustion flame, and a stable flame current can be obtained.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a sectional view of a liquid fuel combustion apparatus showing an embodiment of the present invention.

Reference numeral 1 denotes a carburetor with an opening at its upper end, and 3 a rectifying plate attached to a receiving portion 2 formed by protruding inside the carburetor 1. 3, a large number of vent holes 4, 4' are bored to rectify the mixed gas of vaporized fuel and combustion air, and the vent holes 4 are large in diameter compared to the diameter of the majority of the vent holes 4. There are several ´ marks. Reference numeral 5 denotes a burner head made of ceramic such as lithium-alumina-silica-based petalite, and is provided with a large number of flame ports 6 for blowing out the mixed gas that has been rectified by passing through the rectifier plate 3. . 7 is an annular member for screwing and fixing the burner head 5 to the carburetor 1, which is engaged with a stepped portion 8 formed at the upper end opening of the carburetor 1;
Reference numeral 9 denotes a flame detecting portion, that is, a flame rod, of a known flame detecting device provided in close proximity to the ceramic burner head 5 and the annular member 7. This flame detection section 9 is set at a position just above the large vent hole 4' of the baffle plate 3 described above. 10 is a vaporization mixing chamber formed between the rectifying plate 3 and the bottom surface of the carburetor 1. A heater 11 is installed on the side to heat the vaporization mixing chamber 10 at the beginning of use of this combustion device, and a fuel supply chamber is installed inside. As the outlet of the tube 12 opens,
A stirring blade 13 attached to the shaft end of a fan 16, which will be described later.
is installed. Reference numeral 14 denotes a pressure boosting chamber formed below the vaporization mixing chamber 10 and communicating through an air inlet 15, and a fan 16 for boosting the pressure of primary air is disposed inside.

Now, when the primary air whose static pressure has been increased by the fan 16 is sent from the boosting chamber 14 to the vaporization mixing chamber 10 through the air inlet 15, the liquid sent from the fuel supply pipe 12 into the vaporization mixing chamber 10 is The fuel is atomized by the rotating stirring blade 13, which hits the inner wall of the vaporization mixing chamber 10, which has been heated in advance by the heater 11, and is mixed with the vaporized fuel to form a mixed vaporized fuel. burner head 5 through the vents 4, 4' of
Since the flame is ejected from the flame port 6, combustion can be started by igniting it with a spark plug (not shown). In this case, since the amount of the mixed vaporized fuel sent out from the large ventilation port 4' of the baffle plate 3 is larger than that sent out from the other ventilation ports 4, the flame of the burner head 5 varies in size. As mentioned above, the position of the flame detection part 9 is set to be exactly above the position of the large ventilation hole 4' of the rectifying plate 3, so the flame detection part 9 has a larger flame than other flames. It will be engulfed in flames.

[0011]

[Effects of the Invention] As explained above, the present invention makes the ventilation hole of the rectifying plate, which corresponds to the flame detection section of the flame detection device, larger than the other ventilation holes, thereby making it possible to create a hole in the ceramic burner head. Even if the large number of flame openings that are created are the same size, the flame directly below the flame detection part can be made larger than the others. This is true even during weak combustion, where the flame is short. Therefore, the flame detection section of the flame detection device can always be completely immersed in the combustion flame, so that a stable flame current can be obtained.

[0012] In addition, it is easy to form the vents of the current plate with the above sizes, and on the other hand, in the case of a ceramic burner head, many of the flame ports are of the same size. This is extremely advantageous in terms of reducing the risk of heat shock and the difficulty of processing.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a liquid fuel combustion device showing an embodiment of the present invention.

FIG. 2 is a front view of the current plate in FIG. 1.

FIG. 3 is a cross-sectional view of FIG. 2;

[Explanation of symbols]

1...vaporizer 3... Rectifier plate 4, 4'...Vent 5... Ceramic burner head 6...flame mouth 9...Flame detection part of flame detection device

Claims (1)

[Claims] Claim 1: A carburetor, a baffle plate having a large number of vents for rectifying a mixture of fuel and combustion air vaporized by the vaporizer, and a large number of baffle plates for blowing out the mixed gas that has passed through the baffle plate. It is equipped with a burner head made of ceramics having a flame port, and a flame detection device with a flame detection section provided above the burner head, and the ventilation port of the rectifier plate directly below the flame detection section of this flame detection device is connected to other ventilation. A liquid fuel combustion device characterized by being larger than the mouth.