JPH0256576B2 - - Google Patents

Description

[Detailed Description of the Invention] (a) Field of Industrial Application This invention relates to a small-sized hot water boiler mainly used for domestic hot water supply and space heating.

(b) Conventional technology There are various types of hot water boilers, but for example, as disclosed in Japanese Utility Model Publication No. 52-48036 (see Figure 4), there is a hot water boiler formed inside the water can 1. A burner 4 and an exhaust port 5 are provided on the upper wall 3 of the combustion chamber 2, and the upper wall 3 is provided so as to partition the burner 4 and the exhaust port 5.
It is widely practiced that a cylindrical baffle plate 6 is suspended from the baffle plate 6 and a combustion gas passage 7 is formed between the buffle plate 6 and the water can 1 to reach the exhaust port 5.

In a hot water boiler with such a structure, the fuel ejected from the burner 4 is combusted inside the baffle plate 6, and the combustion gas is reversed at the bottom of the water can 1 and flows into the combustion gas passage 7 between the buffle plate 6 and the water can 1. rise. At this time, the combustion gas comes into contact with the water can 1 due to the action of the buttful piece 8 that is erected from the buttful plate 6 towards the water can 1.
The water in the water can 1 is heated by heat-light exchange. The combustion gas that has undergone heat exchange is then discharged from the exhaust port 5.

(C) Problems to be Solved by the Invention By the way, in the hot water boiler described above, the thermal efficiency depends on the formation of the combustion gas passage 7 from the burner 4 to the exhaust port 5, especially the quality of thermal contact between the combustion gas and the water can 1. It has a big impact. However, in the conventional structure, the combustion gas rising in the combustion gas passage 7 flows toward the portion 7a on the exhaust port 5 side. For this reason, the exhaust port 5
In the opposite part 7b, the combustion gas stagnates (see the shaded area in Figure 5), and this part has the disadvantage that sufficient heat transfer is not carried out, and that the thermal efficiency of the boiler as a whole cannot be sufficiently increased.

Therefore, the applicant had previously proposed in Utility Application No. 165542/1987 a method for making the flow of combustion gas uniform by improving the buttful pieces of the buttful plate, but this method could improve thermal efficiency. On the other hand, there was a problem in that the structure was complicated.

The present invention has been made in view of these conventional problems, and aims to improve thermal efficiency without complicating the structure.

(d) Means for Solving the Problems In order to achieve the above-mentioned object, the present invention changes the conventional cylindrical shape of the buttful plate 20, and has a cross section that is open at a position opposite to the exhaust port 18 with the burner 17 in the center. consists of an arcuate body plate 23, a bottom plate 24 attached to the lower part of the body plate and closing the lower part of the burner 17, and an open end 23 of the body plate 23.
A, 23b and the water can 9 are hermetically sealed.

(e) Operation The hot water boiler with this configuration operates as follows.

First, fuel ejected from the burner 17 burns inside the baffle plate 20. At this time, the body plate 23 of the full plate 20 has the exhaust port 18 centered around the burner 17.
Since the water container 9a located on the opposite side of the exhaust port 18 is opened at a position opposite to the exhaust port 18, the water therein is heated by receiving the radiant heat of the combustion flame. Moreover, since the space between the open ends 23a, 23b of the body plate 23 and the water can 9 is sealed, and the lower part of the burner 17 is closed by the bottom plate 24, the combustion gas coming out from the open part of the body plate 23 is sealed. The water descends along the water can 9a, enters below the bottom plate 24, and flows along the bottom of the water can 9. Then, the combustion gas reversed here evenly spreads through the combustion gas passage 31 formed between the baffle plate 20 and the water can 9b, rises while coming into contact with the water can, and is exhausted from the exhaust port 18.

In this way, by heating the water can on the opposite side of the exhaust port around the burner with the radiant heat of the combustion flame, and heating the water can on the exhaust port side by heat exchange with the combustion gas, heat transfer throughout the water can is achieved. will be carried out well,
In particular, the combustion gas flows along the bottom of the water can 9, promoting heat exchange at the bottom of the water can 9, thereby improving thermal efficiency. In addition, it is sufficient to simply change the round board from a conventional cylinder to a combination of a body board with an arc-shaped cross section and a bottom board, and there is no need to worry about the structure becoming complicated.

(f) Embodiments Hereinafter, embodiments of the present invention shown in the drawings will be described.

In FIGS. 1 to 3, reference numeral 9 denotes a water container in which a water chamber 12 is formed between an outer cylinder 10 and an inner cylinder 11 each having a cylindrical shape with a bottom. A hot water supply port 14 is provided in each part. A combustion chamber 15 is formed inside the water can 9, and is partitioned by an upper wall 16 attached to the upper end of the water can 9. 1
7 is installed through the upper wall 16, and connects the fire port 17a to the combustion chamber 1.
18 is an exhaust port provided on the upper wall 16 together with the burner 17, 19 is a flue connected to the exhaust port 18, and 20 is suspended from the upper wall 16, and 20 is connected to the burner 17 and the exhaust port. This is a baffle plate that partitions off the opening 18 and forms a combustion gas passage 21 between the water can 9 and the water can 9. The full board 20 is the upper wall 1
6, a body plate 23 having an arc-shaped cross section, and a bottom plate 24 attached to the lower part of the body plate 23.
and a pair of partition plates 25a, 25b standing upright from the open ends 23a, 23b of the body plate 23 toward the water can 9.
, gaskets 26 and 27 installed on the partition plates 25a and 25b, respectively, and a heat insulating material 28 such as fire-resistant ceramic fiber or asbestos attached to the inner peripheral wall of the body plate 23. The bottom plate 24 shields the lower part of the burner 17, and the open end 23a of the body plate 23,
The space between 23b and water can 9 is hermetically sealed with partition plates 25a, 25b and gaskets 26, 27. In addition, a large number of buttful pieces 29 are provided on the outer circumferential wall of the body plate 23 so as to face the water can 9.

Next, the action will be explained. When the fuel is ejected from the burner 17, combustion occurs inside the baffle plate 20. At this time, a portion 9a of the water can 9 on the side opposite to the exhaust port 18 centering on the burner 17 receives radiant heat from the combustion flame and is heated. In addition, the open ends 23a, 23b of the body plate 23 and the water can 9 are airtightly partitioned, and the lower part of the burner 17 is shielded by the bottom plate 24, so that the water can be removed from the open end of the body plate 23. The combustion gas enters below the bottom plate 24 through the gap 30 between the bottom plate 24 and the water can 9, and flows along the bottom of the water can 9. Then, the combustion gas reversed here spreads throughout the combustion gas passage 21 formed between the part 9b of the water can 9 on the exhaust port 18 side and the body plate 23 of the buttful plate 20, and ascends through this passage 21. During this time, the buffful piece 29 comes into contact with the water can 9b on the exhaust port side.
The combustion gas that has undergone heat exchange with the water in the water can 9b is exhausted from the exhaust port 18.

In this way, the hot water boiler of this embodiment has burner 1.
7, the water can 9a on the opposite side to the exhaust port 18 is heated by the radiant heat of the combustion flame, and the water can 9b on the exhaust port 18 side is heated by heat exchange with the combustion gas.
Heat transfer throughout the water can is improved compared to the conventional method in which the entire water can is heated by heat exchange with combustion gas. In particular, since the combustion gas flows along the bottom of the water can 9, heat exchange at the bottom of the water can 9 can be promoted. In addition, the full plate 20 is mainly used for the body plate 2.
3 and the bottom plate 24, there is no increase in material cost compared to conventional cylindrical pieces, and there is no need to complicate the shape of the buttful piece 29, so it can be manufactured at low cost. Further, since the heat insulating material 28 is attached to the inner circumferential wall of the body plate 23, combustion heat can be prevented from being transmitted through the body plate 23 and escaping into the combustion gas passage 21.

In addition, compared to the conventional hot water boiler shown in Fig. 4, the hot water boiler of this example lowers the combustion gas exhaust temperature by 55 degrees with the same 31000 Kcal/h burner, and has a thermal efficiency of 4.1.
% improved.

(G) Effects of the invention Since this invention is configured as described above,
By using the radiant heat of the combustion flame and the heat exchange of the combustion gas, it is possible to improve heat transfer throughout the water can, especially at the bottom of the water can, and improve thermal efficiency, without significantly increasing material costs. , there is no need to worry about the structure becoming complicated, and it can be manufactured at low cost and has excellent productivity.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view of a hot water boiler according to an embodiment of the present invention, and FIG. 2 is a longitudinal sectional view of the hot water boiler of FIG. 1.
A' cross-sectional view, Figure 3 is a perspective view of the baffle plate used in Figure 1, Figure 4 is a vertical cross-sectional view of a conventional hot water boiler, and Figure 5 is an explanatory diagram of the combustion gas flow of a conventional hot water boiler. It is. 9... water can, 15... combustion chamber, 16... upper wall,
17... Burner, 18... Smoke exhaust port, 20... Full plate, 21... Combustion gas passage, 23... Body plate,
24...Bottom plate.

Claims (1)

[Claims] 1. A burner and an exhaust port are provided on the upper wall of a combustion chamber formed inside the water can, and a buttful plate is hung from the upper wall to partition the burner and the exhaust port, and a gap between the buttful plate and the water can is In a hot water boiler, which serves as a combustion gas passage leading to an exhaust port, a buttful plate is attached to a body plate with an arc-shaped cross section that is open at a position opposite to the exhaust port with the burner in the center, and to the lower part of the body plate. 1. A hot water boiler comprising: a bottom plate that closes the lower part of the boiler; and an open end of the body plate and a water can are airtightly sealed.