Combustion Apparatus

Abstract

In a combustion apparatus including a burner, a combustion box on a lower side of the burner and enclosing a heat exchanger, and a water jacket in the combustion box and connected to a downstream side of the heat exchanger, the water jacket is arranged to connect together an inlet jacket part disposed in one lateral-side side plate of the combustion box, and an outlet jacket part having a hot water outlet port through jacket parts disposed in the other side plates of the combustion box. An extension jacket part is disposed so as to be elongated from an upper part of the outlet jacket part toward the inlet jacket part and formed such that a sectional center of a tip is positioned below a sectional center of the hot water outlet port.

Description

TECHNICAL FIELD[0001]The present invention relates to a combustion apparatus provided with: a burner for ejecting air-fuel mixture downward; a combustion box which is disposed under the burner in order to enclose the combustion space of the air-fuel mixture to be ejected from the burner; and a heat exchanger disposed in a lower part inside the combustion box.BACKGROUND ART[0002]Conventionally, as this kind of combustion apparatus, there is known an apparatus in Patent Document 1 in which, in order to improve the heat resistivity of the combustion box, a water jacket as a cooling means for cooling the combustion box is disposed in that portion of the combustion box which lies between the burner and the heat exchanger. The water jacket is constituted by: a laterally elongated first jacket part disposed on one of the front-side and the rear-side side plates of the combustion box; a laterally elongated third jacket part disposed on the other of the front-side and the rear-side side plat...

AI Technical Summary

Benefits of technology

[0008]According to this invention, by providing a difference in height between the hot water outlet port and the tip of the fourth jacket part, natural convection will be accelerated inside the fourth jacket part. Therefore, even if the air bubbles due to local heating flow into the fourth jacket part, these air bubbles will be conveyed to the hot-water outlet by the flow of the natural convection. It is thus possible to restrain the air bubbles from getting accumulated in the fourth jacket part. As a result, the fourth jacket part can be prevented from getting deteriorated in durability as a result of accumulation of scales due to temperature rise by the accumulation of air bubbles.

[0009]In addition, in this invention, preferably an upper surface of the fourth jacket part is formed in an inclined surface which is inclined upward from the said tip toward the upper surface of the portion having disposed therein the hot water outlet port of the outlet-side jacket part. According to this arrangement, the air bubbles become more easily flow along the upper surface of the fourth jacket part toward the outlet-side jacket part. The air bubbles can thus be more effectively prevented from staying in the fourth jacket part.

Problems solved by technology

By the way, there are cases where a part of the heat absorbing tubes is locally overheated (boiled) and, consequently, gives rise to generation of air bubbles in the heat absorbing tubes of the heat exchanger.

Then, since that portion of the fourth jacket part in which the air bubbles get accumulated can no longer be cooled by water, the temperature therein will increase and consequently the scales are likely to get accumulated, resulting in deterioration of the durability.

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