JPS61252407A - Hot-air heater - Google Patents

Abstract

PURPOSE:To restrict an accumulation of sound in an air-blowing duct, prevent an occurrence of a resonance phenomenon of a standing waves and the like and reduce a noise level by a method wherein a large number of small holes are made at a rearward part of a the top portion of a combustion cylinder, noise in the combustion cylinder is radiated through the small holes and the noise is reflected rearwardly by a partition plate arranged between the top plate and the combustion cylinder. CONSTITUTION:A combustion cylinder 6 is placed over a combustion part 5 arranged within a blower duct 18 constituted by a top plate 15, a front plate 16, a bottom plate 3 and both side plates, a propeller type blower 7 is installed at upstream side of the combustion cylinder, blowing ports 8 are made at a downstream side of the combustion cylinder, the top plate 15 of the blower duct is inclined toward the downstream side and at the same time the top and rear part of the combustion cylinder 6 is composed of a porous plate 17, and a partition plate 21 dividing the air-blowing passage between the combustion cylinder 6 and the top plate 15 into the upper and lower portions is arranged. This partition plate is provided with an eaves plate A22 and an eaves plate B23 at its up-stream side and its down-stream side, respectively, to cause the air to be easily flowed through the upper passage 24 of the partition plate.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a hot air heater that blows air with low noise for heat exchange in combustion using kerosene or the like as fuel.

Conventional technology An oil-burning heater will be explained as a conventional example.

This type of hot air heater had a configuration as shown in FIGS. 3 and 4. That is, a combustion tube 6 is placed over a combustion section 5 installed in a ventilation duct consisting of a top plate 1, a front plate 2, a bottom plate 3, and both side plates 4, and a propeller blower 7 is installed on the upstream side of the combustion tube. By blowing air into the air duct with this propeller blower, warm air that has undergone heat exchange in the combustion tube is discharged from the blower outlet 8. In addition, a lattice-like catalyst purification filter 10 for purifying the air after combustion is disposed in a cross section in which the front of the combustion cylinder top 9 is tilted forward, and a radiation window is constructed so that the red-hot state of this catalyst purification filter can be seen from the outside. 11, and radiant heat was also used for heating. 12 is a fan guard that holds the propeller blower;
14 is an oil combustion heater.

Problems to be Solved by the Invention In this configuration, in order to extract radiant heat from the red heat of the catalyst purification filter, the front of the top of the combustion cylinder is tilted forward as shown in FIG. Therefore, the noise generated in the combustion section passes through the catalyst purification filter and is radiated toward the corner 13 surrounded by the duct top plate and front plate. Therefore,
Sound was likely to be muffled, and moreover, sound with a standing wave frequency that matched the distance between each wall surface (top plate and bottom plate, front plate and rear surface, etc.) was likely to resonate, increasing the noise level.

The present invention solves such conventional problems by providing a large number of small holes at the rear of the top of the combustion cylinder, allowing the noise inside the combustion cylinder to radiate from the small holes, and installing the noise between the top plate and the combustion cylinder. By reflecting the sound backwards by the partition plate, the purpose is to suppress the increase in sound inside the ventilation duct, prevent the occurrence of resonance phenomena such as standing waves, and reduce the noise level.

Means for Solving the Problems In order to solve the above-mentioned problems, the present invention provides a blower duct consisting of a top plate, a bottom plate, side plates and a front plate, a blower on the upstream side of the blower duct, and a blower on the downstream side of the blower duct. An air outlet is provided on the lower side of the side front plate, and a combustion tube is provided that protrudes upward from the bottom plate to approximately the center of the blower and has a combustion section inside and downward, and the combustion tube is visible on the front plate. A radiation window is arranged, and the top plate is tilted downward in the downstream direction,
Further, a catalytic purification filter is disposed in a cross section in which the front of the combustion cylinder top is tilted forward, the rear of the combustion cylinder top is constituted by a perforated plate, and the ventilation passage between the top plate and the combustion cylinder top is arranged vertically. The structure is such that the partition plate that divides the area into two is inclined downward in the downstream direction.

Effects of the present invention With the above-described configuration, the acoustic impedance when looking at the top of the combustion cylinder from the combustion section is smaller in the perforated plate behind the top of the combustion cylinder than in the catalyst purification filter having passages diagonally with respect to the combustion cylinder. Most of the noise generated in the combustion section is radiated from the perforated plate. The sound radiated from the perforated plate is reflected upstream by the partition plate at the top of the perforated plate, preventing the sound from being reflected many times in the ventilation duct and causing resonance such as muffled sound and standing waves. can be suppressed.

As a result, a part of the frequency of the combustion sound is not amplified due to resonance (a gentle noise spectrum is created, which eliminates unpleasant harshness, and a low-noise hot air heater can be achieved.

EXAMPLE An example of the present invention will be described below with reference to FIGS. 1 and 2.

As shown in FIGS. 1 and 2, the combustion tube 6 is placed over the combustion section 6 installed in the ventilation duct 18, which is composed of the top plate 15, the front plate 16, the bottom plate a, and the side plates 19, The configuration is such that a propeller blower 7 is provided on the upstream side of the cylinder, and a Suita port 8 is provided on the downstream side. The propeller blower heats the room by blowing out warm air that has undergone heat exchange in the combustion tube through the outlet. Moreover, a lattice-like catalyst purification filter 10 for purifying the air after combustion is disposed in a cross section in which the front part of the combustion cylinder is tilted forward, and a radiation window 11 is provided so that the red-hot state of the catalyst purification filter can be seen from the outside. Radiant heat can also be used for heating. Furthermore, the top plate 15 of the air duct is tilted downward toward the downstream side, and
The rear part of the top of the combustion tube 6 is constituted by a perforated plate 17, and a partition plate 21 is provided to divide the ventilation passage between the combustion tube 6 and the top plate 16 into upper and lower parts. This partition plate has an eave plate A22 and an eave plate B23 on the upstream side and the downstream side, respectively, so that air can easily flow through the upper passage 24 of the partition plate.

In such a configuration, when the top of the combustion cylinder is acoustically viewed from the combustion section, the acoustic impedance is smaller in the rear porous plate 17 than in the inclined catalyst purification filter 100 passage. Therefore, most of the noise generated in the combustion section is radiated from the perforated plate. The sound emitted from the perforated plate is reflected to the upstream side of the ventilation duct by the partition plate at the top, preventing the sound from being reflected many times within the ventilation duct, preventing sound muffledness and standing wave resonance. can be suppressed. As a result, some frequencies of the combustion sound are no longer amplified, resulting in noise with a gentle frequency spectrum. Therefore, it is possible to provide the warm air heater 20 with no unpleasant harshness and low noise.

On the other hand, since there are many small holes at the rear of the top of the combustion cylinder, there is concern that the air after combustion will leak through the small holes and reduce the effectiveness of the catalyst purification filter. Because of the air flow, it acts as an air curtain, and the air inside the combustion cylinder rarely leaks through the small holes.

In addition, because a partition plate is provided between the top of the combustion cylinder and the top plate of the air duct, cold air passes through the upper passage to eave plate B23 and front plate 1.
It will come out from between 6 and downward. Therefore, the hot air and cold air coming out of the catalytic purification filter are mixed well, and moderately hot air can be blown out from the outlet, and the front plate, outlet, and top plate can be heated to a high temperature. It is completely safe.

Effects of the Invention As described above, according to the present invention, the combustion sound is radiated from the rear of the top of the combustion cylinder, and the sound is reflected upstream by the partition plate. It is possible to suppress the generation of resonance sounds such as waves, reduce unpleasant harshness, and lower the noise level. Furthermore, by mixing the cold air flowing from the upper passage in front of the outlet with the high-temperature air coming out of the catalyst purification filter, moderately warm air can be blown from the outlet, and the front plate, outlet, etc. It is safe because the top plate is not heated to high temperatures.

[Brief explanation of drawings]

FIG. 1 is a side sectional view of a hot air heater according to an embodiment of the present invention;
Fig. 2 is a plan sectional view of the hot air heater, Fig. 3 is a side sectional view of the conventional hot air heater, and Fig. 4 is a partially cutaway view of the front of the conventional hot air heater. It is a front view. 3...Bottom plate, 5...Combustion part, 6...
... Combustion tube, 7... Blower, 8...
Air outlet, 10... Catalyst purification filter, 11...
... Radiation window, 15 ... Top plate, 16 ...
... Front plate, 17... Perforated plate, 18...
Air duct, 20... Warm air heater, 21...
...Partition plate, 22...Eave plate A123...
... Name of eaves board B0 agent Patent attorney Toshio Nakao and 1 other person 3 ... Tori wipe Figure 2 Figure 3

Claims (2)

[Claims] (1) A blower duct consisting of a top plate, a bottom plate, side plates, and a front plate, a blower provided on the upstream side of the blower duct, an air outlet provided below the front plate on the downstream side, and A combustion tube is provided that protrudes upward to approximately the center of the blower and has a combustion section in the lower part of the interior, and the front plate is provided with a radiation window through which the combustion tube can be seen, and the top plate is tilted downward in the downstream direction. Further, a catalytic purification filter is disposed in a cross section where the front of the combustion cylinder top is tilted forward, and the rear of the combustion cylinder top is constituted by a perforated plate, and the ventilation passage between the top plate and the combustion cylinder top is arranged vertically. A warm air heater with a partition plate that is tilted downward in the downstream direction. (2) The partition plate is provided with an eave plate that slopes downward from above the most upstream end of the combustion tube toward the upstream side, and an eave plate that slopes downward from above the most downstream end of the combustion tube toward the downstream side. Hot air heater.