JPS63282420A - Burner - Google Patents

Abstract

PURPOSE:To prevent the dew condensation in an air discharge pipe during weak combustion in burners for a FF hot air space heater, etc., by detecting the dew condensation or temperature in the air discharge pipe or heat exchanger and regulating the air volume from an auxiliary blower for the secondary air. CONSTITUTION:During weak combustion, when a temperature sensor or dew condensation sensor provided on the side of the air discharge side of a heat exchanger detects the limit temperature for dew condensation, the rotational speed of a motor 6 is raised through a rotation control device 4 to increase the rotational speed of an auxiliary blower 5 in order to increase the secondary air. With this arrangement, the rate of excess air is increased and the volume of the discharge air increases, lowering the heat exchange efficiency and raising the temperature in the air discharge pipe so that the dew condensation is prevented. It is, therefore, made possible to prevent the dew condensation in the discharge pipe, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to combustion devices such as FF hot air heaters and hot water boilers.

BACKGROUND TECHNOLOGY In general, this type of combustion apparatus has an air supply fan 33 driven by a motor 32 and a mixing plate 34 in a burner case 31, as shown in FIG. The gas is combusted at the flame port 36.

At this time, the primary air for combustion is supplied to the vaporization section 3 from the air supply fan 33.
Also, the secondary air for combustion is the same (supplied from the outside of the vaporizer 35 by the air supply fan 33 to the center of the flame port 36 via the secondary air hole 37 of the vaporizer 35). n
It has become so.

Problems to be Solved by the Invention However, when this type of combustion device is used with one device such as an FF hot air heater or hot water boiler that has a heat exchanger,
In order to save energy and use energy effectively by designing equipment with high heat exchange efficiency, equipment that can switch between strong and weak combustion or vary the amount of combustion is designed to avoid condensation of combustion gas in the heat exchanger or exhaust pipe during weak combustion. Occur. In addition, there are problems such as not being able to set the thermal efficiency during strong combustion to a high level, or not increasing the amount of combustion that can be varied from strong to weak.

In addition, if you live in a cold region, there is a risk that condensed water may freeze inside the exhaust pipe.
When this freezing occurs, there are problems such as exhaust gas entering the room and causing serious accidents.

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

First Means to Solve the Problems Firstly, the combustion apparatus of the present invention solves the above problems by separately providing a main blower for supplying primary air for combustion and a sub-blower for supplying secondary air for combustion. , and the auxiliary blower is configured to adjust the amount of air by detecting condensation or temperature in the exhaust pipe or heat exchanger.

Function The present invention maintains a good combustion state with the above configuration, and
The secondary air that does not affect combustion performance is installed in a part of the heat exchanger or in the exhaust pipe, and the sensor is used to adjust the value to an appropriate value to prevent condensation.In other words, during strong combustion, the secondary air By suppressing the amount to the minimum f, the excess air ratio is minimized and high thermal efficiency is obtained.On the other hand, as the transition to intermittent combustion occurs, the exhaust pipe temperature decreases, and when the temperature just before reaching the condensation temperature or just before condensation, the secondary air amount decreases. The excess air ratio is increased little by little to reduce heat exchange efficiency, thereby preventing a drop in exhaust pipe temperature and preventing dew condensation within the exhaust pipe.

EXAMPLE Hereinafter, an example of the present invention will be described based on the accompanying drawings. In FIG. 1, 1 is a burner case, which has a combustion section 1a consisting of a vaporization section 2 and a flame port 3, a mixing plate 4 provided inside the vaporization section 2, and a motor 6 that drives a sub-blower S. 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, 1
0 is the frame rod. FIG. 2 shows an example in which the combustion apparatus of the present invention is used in a hot water boiler, and the heat exchanger 12 provided in the main body 11F3 is connected to the downstream side of the burner case 1. A temperature or dew condensation sensor 13% is attached to the exhaust passage of the heat exchanger 18, and the rotation speed of the sub-blower 5 is changed by this temperature or dew condensation sensor 13. 14
15 is a rotation control device for the main blower 8, 16 is a hot water outlet, and 16b is a hot water inlet.

In the above configuration, the primary air supplied from the main blower 8 in the vaporization section 2 is mixed with fuel supplied from the fuel pump (not shown) via the oil feed pipe 17 at the mixing plate 4. The agitated air is ejected from the flame port 3 and ignited and burned by the ignition electrode 9. On the other hand, the sub-blower 5 is coaxial with the mixing plate 4 and is rotated by a motor 6, which takes in air from the secondary air supply port I9 and fixes the vaporizer cylinder. The air is blown out to the central portion 3m of the burner port 3 through a hole 21a on the outer periphery of the plate 21 and a hole 2a provided on the outer periphery of the vaporization section 2, and is supplied as secondary air.

If the combustion shifts to weak combustion, the discharge amount of the fuel pump (not shown) (according to this, the rotational speed of the main blower 8 is adjusted to an appropriate level).
The sub-air blower S and the motor 6 driving the mixing plate 4 are controlled to an appropriate value by a temperature or dew condensation sensor 13. In other words, in the case of weak combustion, the heat exchange becomes too good and the exhaust temperature decreases, causing the temperature or condensation sensor 1 attached to the exhaust side of the heat exchanger 12 to drop.
3 is near the dew condensation limit temperature, the sensor 13
detects this and increases the rotation speed of the motor 6 via the rotation control device 14 to increase the amount of secondary air. As a result, the excess air ratio increases, which increases the amount of exhaust gas, lowers the heat exchange efficiency, and increases the exhaust pipe temperature.

Next, an embodiment of the pond according to the present invention will be explained using FIG. The difference in FIG. 3 from the previous embodiment is that a part of the primary air supplied through the duct 7 is sucked in through the hole 18m of the partition plate 18 and supplied as secondary air by the sub-blower S. The point is that

With this configuration, the air supply system is unified into one, so the FF
This is advantageous in terms of structure for closed combustion equipment such as i-style heaters. Since the secondary air supply port 19 and related parts are eliminated, there is an advantage that the configuration can be simplified.

Furthermore, if a small diameter air hole 20a is provided in a part of the shelter 20, the air supplied from the sub-blower 5 can be supplied from the air hole 20a as secondary air from the central part 3a of the flame outlet part 3. It also comes to be supplied as air. O
As a result, the excess air ratio during weak combustion can be set even higher with almost no effect on the combustion state, which is effective in preventing dew condensation in the exhaust pipe.

Effects of the Invention As described above, according to the combustion apparatus of the present invention, even in a combustion apparatus designed with a load rate, when dew condensation begins to occur during "weak" combustion, the amount of secondary air is increased and the exhaust temperature is lowered. It can prevent dew condensation. In particular, in the present invention, since the excess air ratio is increased during weak combustion, the dew condensation temperature of the exhaust gas is lowered, and this synergistic effect can more reliably prevent dew condensation. This makes it possible to expand the variable combustion rate (TDR) from strong to weak, making it possible to provide comfortable heating, save energy, and reduce the frequency of turning on and off equipment.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a combustion device in an embodiment of the present invention;
Fig. 2 is a cross-sectional view of the combustion device used in a hot water boiler, and Fig. 3 is a cross-sectional view of the combustion device in the example of the same song.
FIG. 4 is a sectional view of a conventional combustion device. 1...Burner case, 1g...Combustion part, 5...Sub-blower, 8...Main blower,
12...Heat exchanger, 13...Sensor. Name of agent: Patent attorney Toshio Nakao (1 person)
Burnakes jσ - Tsuta despise 5-i; stIL carving 1 8 - main reverse 12 - eim exchange sign 13 - sensor Fig. 1 Fig. 3

Claims (1)

[Claims] A burner case equipped with a combustion section, an exhaust pipe or a heat exchanger provided on the downstream side of the burner case, a main blower that supplies primary air for combustion to the combustion section, and a main blower provided separately from the main blower. It is equipped with a sub-blower that supplies secondary air to the combustion section, and a sensor provided on the exhaust pipe or heat exchanger, and the sensor detects dew condensation or temperature in the exhaust pipe or heat exchanger and controls the flow of air from the sub-blower. A combustion device configured to regulate the amount of air.