JPH083885Y2 - Heat exchanger - Google Patents

Description

[Detailed description of the device]

[0001]

[Field of Industrial Application] In a fin-and-tube type heat exchanger in which a large number of heat-absorbing fins arranged in a water heater are inserted through a heat-absorbing tube and are arranged in parallel at regular intervals, the distance between the holes of the heat-absorbing fins. The present invention relates to the shape of a rising portion for holding and its arrangement.

[0002]

2. Description of the Related Art A conventional heat exchanger will be described below with reference to FIG. The heat-absorbing fins 10 of the heat exchanger are arranged in parallel while maintaining the maximum height dimension t0 of the spacing tube (starting portion) 120 to allow the water supply pipe 20 to pass therethrough, and the spacing tube 120 has a dimension at the tip surface. It is fair to say that the one with the cutout portion 130 that is cut off in an inclined shape that becomes lower than t0 is actually fair 3-5.
0368 (Shokai Sho 62-8578),
The heat-absorbing fins (including the heat-absorbing tubes) are attached in a state of facing the gas burner (not shown) with the maximum height portion (height dimension t0 portion) of the tip end periphery of the interval holding cylinder (starting portion) 120 facing down. ing.

According to the heat exchanger having the above-described structure, the molten brazing material for closely contacting the heat absorbing fins with the heat absorbing tube flows well over the entire circumference, but the spacing cylinder 120 is formed in the upstream half circumference of the combustion gas. Is missing. In this type of heat exchanger that is heated by the combustion gas, the water supply pipe has a high temperature on the upstream side of the combustion gas and is exposed to an atmosphere of a slightly lower temperature on the downstream side, so that the heat of the combustion gas between the upstream side and the downstream side of the combustion gas is increased. It receives stress caused by the difference in expansion. Therefore, in the endothermic tube 20 of the heat exchanger, the exposed portion of the endothermic tube 20 which is the absent portion 130 of the spacing tube 120 is a thin portion, so that stress concentration occurs in the exposed portion and the thermal stress concentration is caused in the endothermic tube 20. There is a drawback that it is unavoidable that cracks (hereinafter referred to as cracks in the text) occur.

[0004]

Therefore, the stress concentration in the above-mentioned conventional heat exchanger is eliminated to prevent cracking of the heat absorbing tube and to secure good brazing property between the heat absorbing fin and the heat absorbing tube. is there.

[0005]

Therefore, in order to eliminate a large exposed portion of the heat absorbing tube in the vicinity of a substantially half peripheral portion near the burner, in the present invention, a rising portion 12 is provided around the through hole 11 formed in the heat absorbing fin 1. Are formed, and the heat exchanging fins 1, 1, ... In the vessel, a notch 13 having a substantially constant depth m is formed in a substantially half circumference of the rising portion 12, and the notch 13 is positioned on the downstream side of the combustion gas. Is.

[0006]

The heat absorbing tube 2 is completely covered by the rising portion 12 in the half circumferential portion of the rising portion 12 of the through hole 11 of the heat absorbing fin 1 on the upstream side of the combustion gas flow, so that the strength is increased and the stress concentration is reduced. Since there is no exposed portion to be generated, cracking does not occur and durability can be improved.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG. The heat-absorbing fins 1 are formed with through holes 11 for inserting the heat-absorbing tubes 2, and a rising portion 12 having a rising dimension t is formed on the peripheral surface of the heat-absorbing fins 1 arranged in the same direction. Insert 2. Heat absorbing fin 1 from both ends
Brazing rod 3 to be described later in a state in which 1, ...
The heat absorbing fins 1 and the heat absorbing tubes 2 are brazed together.

A notch 13 is formed in the upper half of the rising portion 12 at a right angle with a constant axial dimension m (up to approximately the middle portion in FIG. 2). Then, the notch 13 is located above and the brazing rod 3 inserted into the fin 1 is melted, and the molten brazing is flowed from above to perform brazing. The molten braze is received by the lower surface of the notch 13 and flows between the upper half peripheral surface and the lower half peripheral surface of the rising portion 12 and the heat absorbing tube 2 for brazing. Then, a burner (not shown) is installed below the heat exchanger.

Thus, the lower half circumference of the endothermic tube 2 is completely covered by the rising portion 12 of the fin 1, and the upper half circumference is covered by the rising portion 12 whose tip is partially cut off. . Therefore, the lower half circumference of the heat absorbing tube 2 extends over the entire length of the rising portion 12
Since there is no stepped portion that is integrally reinforced with and the stress concentration occurs, the endothermic tube 2 is cracked by the thermal stress generated by the combustion gas flow (indicated by the arrow a) of the burner installed on the lower side. Is something that will never happen. Since the molten brazing material is received by the notch 13 during brazing, not only the lower half peripheral portion but also the upper half peripheral portion is reliably and uniformly turned around the brazing filler metal.

[0010]

As described above, according to the heat exchanger of the present invention, the heat absorption tube is completely covered by the fin rising portion at the lower half circumference which is the upstream side of the combustion gas, Since the endothermic tube is reinforced at the rising portion, the durability can be increased. Further, since the molten brazing material during brazing is received in the vicinity of the middle, there is an effect that brazing of the upper half peripheral portion, which is the downstream side of the combustion gas, can be performed without any problem.

[Brief description of drawings]

FIG. 1 is a schematic front view showing an embodiment of the present invention.

FIG. 2 is an enlarged longitudinal sectional view showing a main part in FIG.

FIG. 3 is an enlarged cross-sectional view showing a main part of FIG.

FIG. 4 is a schematic front view showing a conventional embodiment.

[Explanation of symbols]

 1 Endothermic Fins 2 Endothermic Tubes 11 Through Holes 12 Rise Parts 13 Notches

Claims (1)

[Scope of utility model registration request] 1. A rising portion 12 is formed around a through hole 11 formed in the heat-absorbing fin 1, and the heat-absorbing fins 1, 1, 1 are spaced apart by a height dimension t of the rising portion 12. In a heat exchanger that is brazed by inserting the heat absorbing tubes 2 in a state of being stacked in parallel with each other, a cutout 13 having a substantially constant depth m is formed in a substantially half circumferential portion of the rising portion 12. A heat exchanger characterized in that the notch 13 is located on the downstream side of the combustion gas.