JPH0240437Y2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a heat exchanger for hot water supply used, for example, in domestic hot water supply systems.

<Prior art and its problems> As a hot water supply heat exchanger used in a hot water supply system, there is a heat exchanger shown in FIGS. 1 and 2, for example.
Figure 1 is a partially cutaway front view of the heat exchanger, and Figure 2 is a partially cutaway front view of the heat exchanger.
The figure is a right side view.

In this heat exchanger, a copper finned pipe 3 is passed through a copper case 2 that constitutes a heating chamber 1 inside, and the water passing through the finned pipe 3 is heated in the heating chamber 1, and the copper case 2 is heated. It is designed to be sent outside. In such a heat exchanger for hot water supply, when the finned pipe 3 that performs heat exchange is fixed and restrained by the side plates 4 and 5 of the copper casing 2, the finned pipe 3 is repeatedly burned and stopped.
Due to the thermal expansion and contraction (indicated by arrow A) of the finned pipe 3 or the joints with the side plates 4 and 5, cracks are likely to occur due to stress concentration. For this reason, it is necessary to make one or both ends of the finned pipe 3 free with respect to the copper casing 2. That is, it is necessary to insert the finned pipe 3 into at least one of the side plates 4 and 5 in a free state. However, as shown in the perspective view of FIG. 5, in the past, the copper plate 50 itself was used as the side plate, for example, the side plate 5, which was to be the free end side of the finned pipe 3, and was brazed to the copper casing 2. , Finn 6
When brazing the pipe 3 to the pipe 3, the molten solder passes through the pipe 3 and reaches the copper side plate 50, for example, the pipe 3 at the insertion hole 51 through which the pipe 3 is inserted.
There was a drawback that the copper side plate 50 was dot-soldered. As a result, the finned pipe 3 is constrained, resulting in a drawback that cracks occur due to stress concentration.

The purpose of the present invention is to solve the above-mentioned drawbacks of the prior art, and to provide a heat exchanger for hot water supply that reliably prevents the occurrence of restraint between the finned pipe and the copper casing, and does not cause stress concentration cracks in the finned pipe. do.

<Means for Solving the Problems> The heat exchanger for hot water supply of the present invention which achieves the above object has a copper finned pipe that penetrates the copper casing that constitutes a heating chamber inside the finned pipe. The water supply heat exchanger is configured to heat the water passing through the heating chamber in the heating chamber and send it out to the outside of the copper housing, wherein at least one side plate of the copper housing both sides through which the finned pipe passes through the finned pipe. The finned pipe is configured to be inserted freely into the pipe, that is, the finned pipe is inserted into the pipe insertion hole of the side plate without restraint, and the side plate is configured to be configured to be freely connected to the finned pipe. It is characterized by being made of stainless steel plate.

<Function> By applying a stainless steel plate that is inert to copper solder, such as phosphorous copper solder, to the inside of the side plate, molten solder will not flow through the pipe when brazing the fin to the pipe. Even if the wax flows toward the side plate, the inner stainless steel plate blocks the wax and prevents it from flowing to the outer copper plate. Therefore, it is possible to provide a heat exchanger for hot water supply without the drawback that the pipe is inadvertently brazed to the side plate.

<Example> Fig. 1 is a partially cutaway front view of a heat exchanger for hot water supply showing an embodiment of the present invention, Fig. 2 is a right side view thereof, and Fig.
The figure is a perspective view showing a side plate of a copper casing of a heat exchanger for hot water supply, and FIG. 4 is an exploded perspective view thereof.

In the embodiment, a semi-storage heat exchanger for hot water supply is shown, but the point that the finned pipe 3 penetrates the inside of the copper casing 2 is the same in an instantaneous heat exchanger for hot water supply. The present invention naturally includes this.

As mentioned above, the heat exchanger for hot water supply has a copper finned pipe 3 passing through the copper case 2 that constitutes the heating chamber 1 inside, and a small header 8 from the water inlet 7.
While the water that enters passes through the finned pipe 3, it absorbs heat within the copper casing 2 and becomes hot water. This hot water is in copper container 2
The hot water exits from the main header 9, enters the large header 9, and is discharged from the hot water outlet 10. The hot water that has not been tapped is stored in the large header 9, or returns to the small header 8 through the return pipe 11 and is circulated again. The heating chamber 1 may be an external combustion type or an internal combustion type. In the case of an internal combustion type, a burner (not shown) is placed inside the heating chamber 1, and in the case of an external combustion type, heat from the burner is passed through a burner port 12 to the heating chamber 1.
Blow inside.

Either or both of the side plates 4 and 5 of the copper casing through which the finned pipe 3 penetrates are configured to be free relative to the finned pipe 3. Now, assuming that the side plate 5 is free with respect to the finned pipe 3, its structure will be explained in more detail with reference to FIGS. 3 and 4.

The side plate 5 has a stainless steel plate 510 inert to molten solder applied to the inner side of the copper side plate 500, that is, the side facing the inside of the copper casing 2, as a dam for damming up the molten solder. It is structured in a ivy shape. The actual mounting structure is such that both edges 501, 501 of the copper side plate 500 are bent, and the stainless steel plate 510 is sandwiched between them.
1,501, the bent portion 2a of the copper casing 2,
2a by brazing. Copper side plate 50
0 plays two roles: holding the stainless steel plate 510 and fixing it to the copper casing 2 by bending both edges 501, 501. The stainless steel plate 510 blocks the molten wax flowing through the pipe when the fin 6 is brazed to the pipe 3, and prevents the outer copper side plate 500 and the pipe 3 from being brazed by the flowing wax. Of course, since stainless steel and copper cannot be brazed, the pipe 3 is not brazed to the stainless steel plate 510 and restrained.

The copper side plate 500 and the stainless steel plate 510
Insertion holes 502 and 512 to be communicated with each other are formed respectively, and the finned pipe 3 passes through these insertion holes 502 and 512 in a free state. Further, each insertion hole through which the finned pipe 3 passes is burred to prevent the combustion gas inside the heating chamber 1 from easily leaking to the outside through the gap between the pipe 3 and the hole. Incidentally, the brazing between the fin 6 and the pipe 3 and the brazing between the side plates 4 and 5 and the copper casing 2 are performed at the same time, but they may be performed separately.

<Effects> The present invention has the above configuration, and at least one side plate of the copper casing side plates through which the finned pipe passes is configured to be free with respect to the finned pipe, and the side plate configured to be free is Since the structure is such that a stainless steel plate for damming up the molten wax is applied to the inside, the molten wax that flows along the pipe during brazing allows the free structure of the side plate and the pipe to be brazed. This will surely prevent the inconveniences that would occur if the finned pipe is attached, and the free state between the pipe and the side plate can be maintained without fail, preventing cracks from occurring in the finned pipe due to repeated heating and cooling. The situation can be reliably prevented.

[Brief explanation of drawings]

Fig. 1 is a partially cutaway front view of a heat exchanger for hot water supply showing an embodiment of the present invention, Fig. 2 is a right side view thereof, and Fig.
The figure is a perspective view showing a side plate of a copper casing of a heat exchanger for hot water supply, FIG. 4 is an exploded perspective view thereof, and FIG. 5 is an exploded perspective view of a conventional example. 1: Heating chamber, 2: Copper case, 3: Pipe with fins, 4, 5: Side plate, 6: Fin, 500: Copper side plate, 501: Edge, 510: Stainless steel plate, 5
02,512: Through hole.

Claims (1)

[Scope of utility model registration request] A heat exchanger for hot water supply, in which a copper finned pipe is passed through a copper casing that constitutes a heating chamber inside, and water passing through the finned pipe is heated in the heating chamber and sent to the outside of the copper casing. At least one side plate of the copper casing side plates through which the finned pipe penetrates is configured to be free with respect to the finned pipe, and a dam for molten wax is provided inside the free configured side plate. A heat exchanger for hot water supply characterized by a stainless steel plate