JP3071994B2 - Heat exchanger fin and processing method thereof - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat exchanger for a water heater using gas, kerosene or the like as a heat source, and more particularly to an improvement in a fin opening shape between a heat transfer fin and a heat transfer tube joint.

[0002]

2. Description of the Related Art Hitherto, a fin-type heat exchanger in which a heat transfer tube having a plurality of fins is combined has been frequently used in a water heater because of its high heat efficiency and downsizing.

[0003] In recent years, in a water heater using gas or kerosene as a heat source, a so-called one-can, two-circuit fin heat exchanger in which hot water is supplied and a bath is heated and reheated with a single heat source in order to downsize the appliance. With the advent of vessels, it has become possible not only to reduce the size of instruments but also to reduce costs by simplifying the configuration.

[0004]

However, in the one-can, two-circuit fin heat exchanger described above, as shown in FIG.
As shown in FIG. 8, a hole 51 provided in the fin 50 for penetrating the plurality of heat transfer tubes 48, 49 was opened by using a punch mold 52 having a Dharma-shaped cross-sectional shape.

[0005] As shown in the figure, the punch mold 52 has circular mold portions 52a and 52b having the same outer diameter as the heat transfer tubes 48 and 49.
Are connected to each other via a narrow constricted portion 52c.
Both sides of the constricted portion 52c form a small arc.

Accordingly, when the two heat transfer tubes 48, 49 are passed through the fins 50, a large gap is formed at the contact portion of the arc due to the configuration of the punching die 52, and the heat transfer tubes 48, 49 and the fins 50 are connected. At the time of brazing for close contact, the periphery of the brazing material is deteriorated due to the capillary phenomenon, causing a problem that the heat transfer tubes 48 and 49 cannot be in close contact with each other, so that the required heat efficiency cannot be obtained or one of the heat transfer tubes cannot be obtained. There is a problem that the heating fluid in the heat pipe 48 or 49 boils.

The present invention provides a heat exchanger fin and a heat exchanger fin that can surely adhere heat transfer tubes to each other in a one-can, two-circuit fin heat exchanger, thereby improving heat efficiency and preventing a dangerous phenomenon such as boiling. An object of the present invention is to provide a processing method.

[0008]

According to the present invention, there is provided a one-can-two-circuit heat exchanger in which two heat transfer tubes connected to different flow paths are penetrated in a state of being in close contact with each other and brazed. In the fin, two through-holes for penetrating each heat transfer tube through the fin are punched out so as to have a circular cross section substantially equal to the outer diameter of each heat transfer tube, and a portion where the two heat transfer tubes are in close contact is superimposed. The fins of the heat exchanger are characterized in that the fins of the heat exchanger are connected to each other and have an acute-angled edge portion sandwiched between adjacent arcs of both through-holes in the communication portion, and a brazing material through-hole is provided in the edge portion. It will not be provided.

Another feature is that one through hole has a smaller diameter than the other through hole.

[0010] The two through holes are also characterized in that they are formed in separate steps.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below with reference to the embodiments shown in the accompanying drawings.

FIG. 1 conceptually shows the overall structure of a one-can, two-circuit bath kettle A provided with a heat exchanger comprising fins according to the present invention. And a heat transfer pipe 13 for hot water supply penetrate to share a large number of fins 11 arranged in parallel.

A burner 14 for heating the can 10 is provided below the can 10, and a solenoid valve 16 and a proportional valve 17 are provided in a fuel supply path 15 to the burner 14. Installed.

Further, the bath heat transfer pipe 12 is connected to a bathtub 22 through a circulation flow path 21 in which a circulation pump 20 is mounted halfway.

On the other hand, a water supply pipe 24 is connected to the water inlet 23 of the heat transfer pipe 13 for hot water supply, and a hot water supply pipe 26 is connected to the outlet 25.

A water supply detector 27 and a water supply temperature detector 29 are mounted on the water supply pipe 24, while a water supply temperature detector 28 is mounted on the hot water supply pipe 26.

In FIG. 1, C indicates a control device, which controls the operation of the solenoid valve 16, the proportional valve 17, and the circulation pump 20 based on detection signals of a water amount detector 27 and a hot water supply temperature detector 28. Is what you do. R is a remote controller.

A 1-can 2-circuit bath kettle A having such a configuration
By using a single can body 10 by burning the burner 14,
Not only can the bathtub 22 be refired, but also hot water can be supplied to a shower or kitchen through the hot water supply pipe 26.

According to the present invention, in the heat exchanger having the above structure, the degree of adhesion between the heat transfer tubes, that is, in this embodiment, between the bath heat transfer tube 12 and the hot water supply heat transfer tube 13 is improved. It is characterized in that it has a structure that can maintain and improve the thermal efficiency.

Hereinafter, a specific description will be given with reference to FIGS.

As shown in FIGS. 2 and 3, the rectangular plate-shaped fin 11 is provided with a pair of heat transfer tube through holes 30 and 31 in the vertical direction at intervals in the width direction. , 31 within
The above-described bath heat transfer tube 12 and hot water supply heat transfer tube 13 penetrate.

As shown in FIG. 3, two through holes 30, 31
Have a circular cross section substantially equal to the outer diameter of the heat transfer tubes 12 and 13 to be penetrated, and form a narrow width communicating portion 32 by overlapping portions where the heat transfer tubes 12 and 13 are in close contact with each other to communicate with each other. .

The communicating portion 32 has, on both side surfaces thereof, acute-angled edge portions 33 and 34 sandwiched between adjacent arcs 30a and 31a of the through holes 30 and 31, respectively.

Further, in FIG. 2 and FIG.
In the upper part, a brazing material through hole 35 through which a rod-shaped brazing material (not shown) is inserted is provided.

With this configuration, at the time of brazing, the melted brazing material flows along the outer circumference of the heat transfer tubes 12 and 13, and the triangular edge portions formed on both side surfaces of the communication portion 32 by the capillary phenomenon. Since it turns to the tip of 33, 34, the degree of adhesion between the heat transfer tubes 12, 13 is improved, and not only the required thermal efficiency can be maintained and improved, but also the danger of boiling can be prevented.

FIG. 4 shows another embodiment. In this embodiment,
The through hole 30 for the heat transfer tube 12 for the bath and the through hole for the heat transfer tube 13 for the hot water supply
In order to make the diameter smaller than 31 and to perform brazing more reliably, not only the brazing material through hole 36 is provided above the through hole for the 33
It is also characterized in that a brazing material through hole 37 is provided.

[0027] Even in such a configuration, when brazing,
As the melted brazing material flows along the outer circumference of the heat transfer tubes 12 and 13 and turns to the tips of the triangular edges 33 and 34 formed on both sides of the communication portion 32 by capillary action,
The degree of adhesion between the heat transfer tubes 12 and 13 is improved, so that not only the required thermal efficiency can be maintained and improved, but also the danger of boiling can be prevented.

Furthermore, since the brazing is performed not only by the brazing material disposed in the brazing material through hole 36 but also by the brazing material eluted from the brazing material disposed in the brazing material through hole 37, the heat transfer tubes 12 and 13 are brazed. The degree of adhesion between them can be further improved, and the danger of boiling can be more reliably prevented.

Next, with reference to FIG. 5 and FIG. 6, through-holes through which the above-described bath heat transfer tubes 12 and hot water supply heat transfer tubes 13 pass.
A fin processing method for providing the fins 30, 31 on the fin 11 will be specifically described.

FIG. 5 shows a punch mechanism B for forming through holes in the fins 11 for mounting members required as heat exchangers, including the through holes 30 and 31 described above.

As shown in the figure, a punch mechanism B comprises a plurality of punch dies, which are disposed above a belt-shaped sheet metal P flowing on a conveyor at a predetermined interval in the flow direction of the sheet metal C. and a B ₁ ~B _7.

Each of the punch dies B _{1 to} B ₇ has different types of punches mounted on the lower surface thereof.

Then, as shown in FIG. 6, in each of the first to seventh steps, the sheet metal C is sequentially punched by successively descending the punching dies B _{1 to} B _7, thereby punching out various through holes. Can be formed.

That is, in the first step, first, the punching die B ₁ is lowered to penetrate the through hole 40 for the bath heat transfer tube 12 and the hot water supply heat transfer tube 13 formed in the upper stage of the fin 11. Holes 41 are punched out in a zigzag pattern.

[0035] In the second step, and moves down the punch die B _2, is formed in the lower fins 11, punched holes 30 for the bath heat transfer pipe 12.

[0036] In the third step, and moves down the punch die B _3, is formed in the lower fins 11, punched holes 31 for the heat transfer pipe 13.

At this time, each of the two through holes 30 and 31 has a circular cross section substantially equal to the outer diameter of the heat transfer tubes 12 and 13 to be penetrated, and a portion where the heat transfer tubes 12 and 13 are in close contact with each other is superposed. By punching, a narrow communicating portion 32 can be formed, and both side surfaces thereof have two through holes.
The acute edge portions 33, 34 sandwiched between the adjacent circular arcs 30a, 31a of the 30, 31 can be formed respectively.

In the third step, a slit-shaped heat shield hole 42 is formed at a position corresponding to both shoulders of the through hole 30.

The heat shield holes 42 make it possible to adjust the ratio of heat absorption in the heat transfer tubes 41 and 30 disposed at the upper and lower stages of the fins 11, and to reduce the heat transfer due to the condensation phenomenon of the heat exchanger and the generation of excessive thermal stress. Cracks in the heat tube can be prevented.

At the same time, a first cut-out hole 43 having a mountain shape is formed along the lower circular arc of the through-hole 31, and cut-out notches 44 are formed on both sides thereof.

[0041] In the fourth step, and moves down the punch die B _4, the edge portion 33 provided on one side of the upper portion of the through hole 30 and the connecting part 32, respectively, the brazing material through holes 36, 37 Form.

Further, a heat shield hole 42 is added around the through hole 30.

At the same time, a second cut hole 45 having a mountain shape is formed along the lower arc of the through hole 31 and the second cut hole 45 is formed.
Is communicated with the first cutting hole 43.

[0044]

[0045] In the fifth step, and moves down the punch die B _5, both sides of the sheet metal P by bending process to form the bent portion 45a.

Further, a brazing material through hole 48 is formed above the through hole 40.

In the sixth step, the punching die B ₆ is lowered to further add a heat shield hole 42 around the through hole 30.

In the seventh step, the punching die B ₇ is lowered, and the third _and fourth peaks are formed along the lower arc of the through hole 31.
The cutting holes 46 and 47 are formed, and the cutting holes 46 and 47 are communicated with the adjacent cutting holes 43 and 45 and the cutting notch 44 to form the fin 11.

As described above, in this embodiment, the through holes 30 and 31 through which the two heat transfer tubes 12 and 13 come into close contact with each other are separately formed by press working using the punching die B. Since piercing can be performed in the process, the fin 11 having the sharp edge portions 33, 34 on both sides of the continuous portion 32 of the through holes 30, 31 can be easily and reliably manufactured.

[0050]

As described above, according to the present invention,
When brazing the heat transfer tubes to the fins, the brazing material that has melted to the sharp edge due to the capillary phenomenon wraps around, improving the degree of adhesion between the heat transfer tubes, not only maintaining and improving the required thermal efficiency, but also causing the risk of boiling. Can also be prevented beforehand.

Further, since the brazing material through hole is provided at the edge portion, the brazing is performed by the brazing material eluted from the brazing material disposed in the brazing material through hole. The degree can be further improved, and the danger of boiling can be more reliably prevented.

Also, since one through hole has a smaller diameter than the other through hole, for example, if the through hole of the bath heat transfer tube is smaller than the through hole of the hot water supply tube, the bath heat transfer tube may have a smaller diameter. It is possible to prevent the fluid in the inside from boiling.

Further, since the two through holes are formed in different steps, it is possible to easily and surely manufacture a fin having sharp edges on both sides of a continuous portion of the two through holes. Can be.

[Brief description of the drawings]

FIG. 1 is an explanatory view of the overall configuration of a one-can, two-circuit bath kettle provided with a heat exchanger fin according to the present invention.

FIG. 2 is an explanatory diagram of an internal structure of a heat exchanger.

FIG. 3 is an explanatory diagram of a shape of a fin of the heat exchanger.

FIG. 4 is an explanatory diagram of a shape of a fin of a heat exchanger according to another embodiment.

FIG. 5 is a perspective view of a punch die used for processing fins of a heat exchanger.

FIG. 6 is an explanatory diagram of a fin processing step using the punch die.

FIG. 7 is a diagram illustrating the shape of a conventional heat exchanger fin.

FIG. 8 is a perspective view of a punch die used for processing the fin.

[Explanation of symbols]

 A 1-can 2-circuit bath kettle B Punch mechanism P Sheet metal 11 Fin 12 Heat transfer tube for bath 13 Heat transfer tube for hot water supply 30 Through hole 30a Arc 31 Through hole 31a Arc 32 Communication part 33 Edge part 34 Edge part

Continuation of the front page (72) Inventor Seiji Bando 431-1 Uozakihama-cho, Higashinada-ku, Kobe-shi, Hyogo Japan Inside (72) Inventor Takashi Takizawa 431-1 Uozakihama-cho, Higashinada-ku, Kobe-shi, Hyogo Nippon Yupro Inside (72) Inventor Noboru Kawachi 43-1, Uozakihama-cho, Higashinada-ku, Kobe-shi, Hyogo Within Nippon Yupro Corporation (72) Inventor Hiroshi Munemura 43-1 Uozakihama-cho, Higashinada-ku, Kobe-shi, Hyogo Nippon Yupro Corporation (56) References JP-A-60-126540 (JP, A) JP-A-2-154942 (JP, A) JP-A-62-55037 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) F24H 1/00 303 F28F 1/00

Claims (3)

(57) [Claims] 1. A fin of a one-can, two-circuit heat exchanger in which two heat transfer tubes connected to mutually different flow paths are penetrated in close contact with each other and are brazed. The two through-holes are punched and formed so as to have a circular cross section that is substantially equal to the outer diameter of each heat transfer tube, and the two heat transfer tubes are brought into close contact with each other to overlap and communicate with each other. Forming an acute angle edge portion sandwiched between adjacent arcs of both through holes ,
Also, a fin of a heat exchanger, wherein a brazing material through hole is provided at an edge portion . 2. The heat exchanger fin according to claim 1, wherein one of the through holes has a diameter smaller than that of the other through hole. 3. The heat exchanger fin according to claim 1, wherein each of the two through holes is formed in a separate step.