JPS63263317A - Combustion equipment - Google Patents

Abstract

PURPOSE:To prevent an increase in the thermal efficiency in the weak combustion and prevent the fall of the discharged gas temperature by providing separately a main blower which supplies primary air for combustion and an auxiliary blower which supplies secondary air for combustion and, further, constituting the main blower so as to make it possible to control the volume of air by a combustion control device. CONSTITUTION:The primary air which is supplied from a main blower in a carburation section 2 is stirred by a mixing plate 4 with fuel that is supplied through an oil conveying pipe 11, and the mixture gas is jetted out from a flame hole section 3 and ignited and burns. On the other hand, an auxiliary blower 5 rotates by a motor on a shaft which is the shaft for the mixing plate 4 and sucks air from a secondary supply air opening 5a and the sucked air jets out through holes 13a on the outer circumference of a carburating cylinder fixed plate 13 and holes 2a provided on the outer circumference of a vaporization section to the central section 3a of the flame holes section 3 to be supplied as secondary air. When the combustion moves to weak combustion, the rotational speed of the main blower 8 is regulated according to the fuel by a combustion control device 12, and controlled to give a proper volume of the primary air, but the secondary air volume does not change. As a result, the volume of the secondary air increases, raising the rate of the surplus air and lowering the thermal efficiency and raising the temperature of the discharged gas to prevent moisture condensation.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a combustion device used in forced supply and discharge hot air heaters, hot water boilers, and the like.

2. Description of the Related Art In general, this type of combustion apparatus has an air supply fan 23 driven by a moder 22 and a mixing plate 24 in a burner case 21, as shown in FIG. It is combusted at the mouth part 26.

At this time, the primary air for combustion is supplied to the vaporization section 2 from the air supply fan 2a.
5, and the secondary air for combustion is also supplied from the outside of the vaporizer 25 to the secondary air hole 27 by the air supply fan 2a.
The fuel is supplied to the center of the burner port 26 through the burner port 26.

Problems to be Solved by the Invention However, when this type of combustion device is used in devices such as forced air heaters and hot water boilers that have a heat exchanger, the heat exchange efficiency of the device is designed to be quite high. In order to save energy and use energy effectively, devices that can switch between strong and weak combustion or vary the amount of combustion generate condensation from the combustion gas inside the heat exchanger or exhaust pipe during weak combustion.

Therefore, there have been problems such as not being able to set a high thermal efficiency during strong combustion, or not being able to vary the amount of combustion from strong to weak. In addition, in cold regions, there is a risk that condensed water may freeze in the exhaust pipe, and if this freezing occurs, exhaust gas may enter the room, causing a serious accident.

The present invention solves such conventional problems and aims to prevent dew condensation inside the heat exchanger or the exhaust pipe during weak combustion.

Means for Solving the Problems In order to solve the above problems, the combustion apparatus of the present invention separately provides a main blower for supplying primary air for combustion and a sub-blower for supplying secondary air for combustion, and The main blower is configured so that the amount of air can be adjusted by a combustion control device.

Function: With the above configuration, the primary air for maintaining a good combustion state can be varied to an appropriate value according to the amount of combustion.
Secondary air, which does not greatly affect dedicated combustion performance, is constant, that is, the amount of secondary air does not change even during weak combustion, resulting in a large excess air ratio, which prevents an increase in thermal efficiency during weak combustion and reduces the exhaust gas temperature. In other words, dew condensation inside the heat exchanger or exhaust pipe can be prevented.

Example Embodiments of the present invention will be described below based on the accompanying drawings.

In FIG. 1, reference numeral 1 denotes a burner case, which has a combustion section 1a consisting of a vaporization section 2 and a flame port a, a mixing plate 4 provided inside the vaporization section 2, and a motor 6 that drives a sub-blower 5. are doing. Further, a main blower 8 is connected to the side surface of the burner case 1 via a duct 7. 9 is the ignition electrode, 10
is a frame rond.

In the above configuration, the primary air supplied from the main blower 8 in the vaporizer 2 is stirred by the mixing plate 4 with the fuel supplied from the fuel pump (not shown) through the oil pipe 11, and It is ejected from the part 3 and ignited and burned by the ignition electrode 9. - The blower 5 is coaxial with the mixing plate 4 and rotated by a motor 6, and takes in air from the secondary air supply port 5a through the holes 13a on the outer periphery of the vaporizing tube fixing plate 13 and the holes 2a provided on the outer periphery of the vaporizing section 2. The air is blown out to the central portion 3a of the flame port 3 through the air and supplied as secondary air.

When shifting to weak combustion here, the rotational speed of the main blower 8 is changed according to the fuel from the combustion pump (not shown) in the combustion control device 1.
The motor 6 that drives the sub-blower 5 and the mixing plate 4
The secondary air needle, which is rotating at a constant rate, does not change. Therefore, the amount of secondary air increases as a result, and the excess air ratio increases.

When the excess air ratio increases, the amount of exhaust gas passing through the heat exchanger and exhaust pipe increases, resulting in a decrease in thermal efficiency. A decrease in thermal efficiency increases the exhaust gas temperature and prevents condensation.

Next, another embodiment of the present invention will be described using FIG. 2. The difference in FIG. 2 from the previous embodiment is that a part of the primary air supplied through the duct 7 is sucked in through the hole 14a of the partition plate 14 and supplied as secondary air by the sub-blower 5. The point is that there is.

According to this configuration, since the air supply system is unified in one part, it is advantageous in terms of configuration for closed combustion equipment such as forced air supply and exhaust hot air heaters. Further, since the secondary air supply port 12 and related parts are eliminated, there is an advantage that the configuration can be simplified.

Furthermore, a small air hole 15a in a part of the shelter 15 -
If provided, the air supplied from the sub-blower 5 can be
In addition to being supplied as secondary air from the central portion 3a, tertiary air is also supplied from the air holes. As a result, the excess air ratio during weak combustion becomes even higher, resulting in an increase in exhaust gas temperature, that is, a more reliable effect of preventing dew condensation. Note that the tertiary air is the flame 16 formed near the flame port 3.
Because it does not come into direct contact with the fuel, it will not have a negative effect on combustion even if too much is supplied.

Effects of the Invention As described above, according to the combustion apparatus of the present invention, when used in a device having a heat exchanger for combustion, even in a heat exchanger designed to be highly efficient in strong combustion, the exhaust gas during weak combustion is reduced. It keeps the gas temperature high and prevents condensation inside the exhaust pipe. Increasing the excess air ratio, especially during weak combustion, lowers the dew condensation temperature of the exhaust gas, which synergistically increases the dew condensation prevention effect, resulting in a higher dew condensation prevention effect.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a combustion device in an embodiment of the present invention;
Figure 2 is a sectional view of a combustion device in another embodiment;
The figure is a sectional view of a conventional combustion device. 1...Panakenu, la...Combustion section, 5...Sub-blower, 8...Main blower,
Combustion control device for 12... Name of agent: Patent attorney Toshio Nakao and 1 other person/-
−-Noguichi Nakoos δ-Lord, sending, form＼

Claims (1)

[Claims] A combustion section is provided in the burner case, and primary air for combustion is supplied to this combustion section from a main blower for combustion, and secondary air is supplied by a sub-blower separate from the main blower for combustion. A combustion device in which the main blower for combustion is configured to have an air amount adjusted by a combustion control device.