JPH0541888B2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a forced air supply/exhaust type combustion device.

[Conventional technology]

In conventional forced-air combustion devices, the air supplied for combustion is approximately the amount of air that is theoretically required.
It is around 1.6 times. This is due to inappropriate construction of the secondary air chamber and/or combustion chamber of the combustion device. That is, to explain using FIG. 1 which is an embodiment of the present invention, the direction is changed by the inclined plate 14 provided below the burner 1, and the fuel is supplied to the burners 1, 1 through the rectifying hole 11 of the partition plate 10. Ideally, the secondary air rises directly above the burners 1, 1 and between the burners 1 to form a secondary flame around the primary flame. However, because the planar area of the combustion chamber 4 above the burners 1 is wider than the planar area of the plurality of burners 1, the secondary air becomes turbulent before reaching the sides of the burners 1, 1, and some of the air reaches the primary flame. It flows upward along the wall surface of the combustion chamber 4 without supplying secondary air to the combustion chamber 4 and is exhausted together with the combustion gas.

[Problem to be solved by the invention]

However, the above-mentioned conventional technology has the problem that the excess air ratio in the combustion chamber becomes high and it is difficult to prevent a decrease in thermal efficiency due to an increase in exhaust gas loss and to downsize the fan capacity. Furthermore, there is a problem in that the flame length increases due to insufficient supply of secondary air to the burner flame opening, and the combustion chamber must be enlarged. The present invention has been made in view of the above-mentioned problems, and is a forced air supply/exhaust combustion method that can significantly reduce the excess air ratio, improve thermal efficiency, and downsize the fan, as well as downsize the combustion chamber through short flame combustion. The purpose is to provide equipment.

[Means to solve the problem]

The structure of the present invention for achieving the above object will be explained using FIGS. 1 to 3 corresponding to the embodiments. The lower part of the burner 1 is partitioned by a partition plate 10 having a plurality of secondary air rectification holes 11, and a fan 6 is connected to the upstream side of a primary air chamber 8 in which a nozzle 7 is provided, and the air from the fan 6 is connected to the primary air chamber 8. air chamber 8 for blowing air and secondary air;
9, and an inclined plate 14 is provided so that the cross section of the air chamber 9 is temporarily reduced from the bottom of the secondary air chamber 9 below the partition plate 10 in the flow direction of the secondary air.
In a forced air supply/exhaust type combustion device 13 in which an opening is provided between the tip of the combustion chamber 4 and the partition plate 10, a plurality of burners 1 are arranged in parallel from the four walls of the combustion chamber 1 in the vicinity of the flame port 2 on the outside. To this end, a technical measure is taken in which a diaphragm plate 12 is provided.

[Effect]

According to the above-described means, the combustion air supplied by the fan 6 is sent into the burner 1 while being mixed with the fuel gas injected from the nozzle 7 as primary air, and the combustion air is sent to the burner port 2 to cause a primary flame. form. The remaining combustion air is sent to the secondary air chamber 9 as secondary air, and the secondary air is corrected to an even wind pressure by the inclined plate 14 and changed direction. The flow is rectified by the rectifying hole 11 and rises, and the gap between the flame port part 2 of the burner 1, 1 located outside the plurality of burners 1, 1, 1 arranged in parallel and the throttle plate 12, the flame port The flame openings 2 and 2 of the burner 1 rise through the gap between the burner 1
It flows to the second side and forms a secondary flame around the outer periphery of the primary flame. That is, the secondary air that has flowed into every corner of the secondary air chamber 9 at the bottom of the partition plate 10 is prevented from flowing directly to the top of the combustion chamber 4 along the four peripheral walls of the combustion chamber 4 due to the inclined plate 14 and the throttle plate 12. The rectified current is concentrated around the flame openings 2 of the plurality of burners 1. and aperture plate 12
In the gap between the flame outlet part 2 and the flame outlet part 2, and in the vicinity of the flame outlet part 2 above the gap between the flame outlet parts 2, 2, vortices are generated in the flow of secondary air, and the flame formed in the flame outlet part 2 is The secondary air is sufficiently diffused, a short flame is formed at the flame port 2, and good combustion is achieved.

【Example】

Embodiments of the present invention will be described below with reference to FIGS. 1 to 3. 13 is a forced air supply and exhaust type combustion device; 1 is a
A burner in which an elongated planar flame port 2 is formed at the top of a mixing tube that mixes gas and primary air,
A plurality of the burners 1 are fixed in parallel with the bottom of the device 13 with a gap between them, and the burners 1, 1,
1. A partition plate 10 formed of a metal plate such as stainless steel is provided with a plurality of rectifying holes 11 in the entire lower area, and a secondary air chamber 9 is provided between the partition plate 10 and the bottom of the device 13. It is formed. A plurality of nozzles 7 facing each other and connected to a gas pipe are fixed to the openings of the plurality of burners 1, 1, 1 to form a primary air chamber 8. 14 is a burner 1 installed at the bottom of the device 13 at the bottom of the partition plate 10 from the primary air chamber 8 side.
It is an inclined plate with an upward slope toward the end, and the inclined plate 14 corrects the secondary air sent from the fan 6 to equal wind pressure and converts it into a vertical direction, and is a partition having rectifying holes 11. The rectified air is uniformly blown through the plate 10 to the side surface of the burner 1 flame port 2. 4 is a combustion chamber formed above the burners 1, 1, 1, and above the combustion chamber 4 is provided a heat exchanger 3 having an exhaust chamber 5. 12 is formed of a plate-like material such as stainless steel, and has a rectangular opening slightly larger than the planar area of the plurality of burner ports 2, 2, 2 of the plurality of burners 1, 1, 1 approximately in the center. However, it is a diaphragm plate whose outer periphery is approximately the same size as the combustion chamber 4, and the opening end face of the diaphragm plate 12 is located at a height slightly below the flame port 2 which is on the outside. It is fixed by welding or the like to the four circumferential inner walls of the combustion chamber 4 with a certain gap provided between the side surface of the outer flame port 2 and the tips and bases of the plurality of flame ports 2.

【Effect of the invention】

The present invention is equipped with a fan, multiple burners, a combustion chamber, a heat exchanger, etc., the lower part of the burner is partitioned by a partition plate with multiple secondary air rectification holes, and the fan is installed on the upstream side of the primary air chamber provided with the nozzle. At the same time, an air chamber is provided in which the air from the fan is blown as primary air and secondary air, and the cross section of the air chamber is temporarily reduced in the flow direction of the secondary air from the bottom of the secondary air chamber below the partition plate. In a forced air supply/exhaust type combustion device in which a slanted plate is provided and an opening is provided between the tip of the slanted plate and a partition plate, a plurality of flame ports on the outside of a plurality of burners are arranged in parallel from the four walls of the combustion chamber. By providing a throttle plate near the periphery of the fan, the excess air ratio can be significantly reduced, thermal efficiency can be improved, and the fan can be made smaller, and the combustion chamber can be made smaller due to short flame combustion.

[Brief explanation of the drawing]

FIG. 1 is a front view showing an embodiment of the present invention, FIG. 2 is a side view showing an embodiment of the present invention, and FIG. 3 is a plan view of essential parts showing an embodiment of the present invention. Explanation of symbols, 1...burner, 2...flame port, 3
... Heat exchanger, 4 ... Combustion chamber, 5 ... Exhaust chamber, 6
...Fan, 7...Nozzle, 8...Primary air chamber,
9... Secondary air chamber, 10... Partition plate, 11... Rectifying hole, 12... Throttle plate, 13... Forced supply/exhaust type combustion device, 14... Inclined plate.

Claims (1)

[Claims] 1 Equipped with a fan, multiple burners, a combustion chamber, a heat exchanger, etc., the lower part of the burner is partitioned with a partition plate having multiple secondary air rectification holes, and the fan is connected to the upstream side of the primary air chamber provided with a nozzle. An air chamber is provided that blows air from a fan as primary air and secondary air, and the cross section of the air chamber is inclined so that the cross section of the air chamber is slightly reduced in the flow direction of the secondary air from the bottom of the secondary air chamber below the partition plate. In a forced air supply/exhaust type combustion device in which a plate is provided and an opening is provided between the tip of the inclined plate and the partition plate, the vicinity of the flame opening on the outside of a plurality of burners arranged in parallel from the four walls of the combustion chamber. A forced air supply/exhaust type combustion device characterized by being provided with a throttle plate.