JP2003269880A - Heat exchanger - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat exchanger with the minimum number of joints and a high degree of design freedom while maintaining conventional heat exchanging performance combining the advantages of reliability in airtightness and refrigerant leakage resistance, heat transfer performance and the high degree of design freedom. <P>SOLUTION: In the cross fin type heat exchanger, only one refrigerant pipe is brought into contact with one independent fin. It is structured to joint the fin to one refrigerant pipe which is originally linear, and to perform planar or three-dimensional bending work the optional number of times to have an optional length. A bent part is composed of a combination of the same minimum bend radius and an optional micro linear part. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The heat exchanger structure of the present invention relates to a cross fin type heat exchanger having a structure in which refrigerant pipes and fins are combined, and particularly, it is possible to suppress joining of refrigerant pipes by brazing as much as possible. The present invention relates to a heat exchanger having a writing-structured refrigerant pipe, and more particularly to a refrigerator using the heat exchanger.

[0002]

2. Description of the Related Art A conventional cross fin type heat exchanger having a structure in which a refrigerant pipe and fins are combined is described in "Tube Forming" (First Edition, 1992, Corona Publishing Co., Ltd.), p. 63, edited by the Japan Society for Plasticity Processing. As described above, it is composed of a plurality of refrigerant tubes arranged in parallel at regular intervals and a plurality of fins arranged at regular intervals in a direction perpendicular to the refrigerant tubes.
At this time, one independent fin is provided with a plurality of through holes, a refrigerant pipe is passed through each of the through holes, and the inside of each refrigerant pipe in the through hole is outside the inner diameter thereof. The fins and the refrigerant pipes are fastened by press-fitting a pipe expanding mandrel having a slightly larger diameter. Further, the refrigerant tubes are joined by brazing or the like by using individual parts that have been bent to 180 degrees in another process, and straight tubes and 180 degree bent tubes are alternately joined to form a heat exchanger. . Fins are provided with slits as needed to increase heat exchange performance.

Further, as a cross fin type heat exchanger having a structure in which a refrigerant pipe is meandered and has no connecting portion, there is disclosed in Japanese Patent Laid-Open No. Hei 9 (1998)
As described in Japanese Patent Laid-Open No. 96496, there is a method in which a refrigerant pipe is processed into a meandering shape with a single stroke and then the refrigerant pipe is pushed into the notches of the fins. Further, as generally used as a heat exchanger for refrigerators, particularly as a condenser, a refrigerant pipe P ′ spirally wound with a band-shaped fin F ′ as shown in FIG. 10 has a planar (two-dimensional) shape. Alternatively, there was a spiral fin-shaped heat exchanger that was meanderingly bent into a three-dimensional shape.

[0004]

Of the above-mentioned prior art, it is composed of a plurality of refrigerant pipes arranged in parallel at regular intervals and a plurality of fins arranged at regular intervals in a direction perpendicular to the refrigerant pipes. In the case of the cross-fin type heat exchanger, the straight tubes and the 180-degree bent tubes are alternately joined to form the heat exchanger, so even if it is attempted to improve the airtightness of the product and the reliability against refrigerant leakage. However, there is a problem that the reliability is reduced by a multiplier of the number of joints. For example, when using a flammable refrigerant for heat exchange, in terms of safety measures, a structure with less refrigerant leakage, that is, a heat exchanger structure with fewer joints becomes effective,
The conventional structure has a problem that sufficient reliability cannot be obtained.

Further, in the case of a heat exchanger having a structure in which the joint portion of the refrigerant pipe is eliminated, for example, the refrigerant pipe is processed into a meandering shape with a single stroke, and then the notch portion of the fin is clicked,
The structure in which the refrigerant pipe and the fin are not in close contact with each other on the entire circumference, the binding force between the refrigerant pipe and the fin is inferior to that of the expansion method, and the fin heat transfer area is reduced by notching the fin in the refrigerant pipe insertion part. There was a problem that the heat exchange performance was inferior to that of the heat exchanger having the tube expansion structure.

Further, in the case of a spiral fin type heat exchanger, a band-shaped fin is spirally wound around an originally linear refrigerant pipe and then bent in a meandering shape, so that the heat exchanger can be installed in an arbitrary shape in the installation space of the heat exchanger. It has the advantage of being able to form exchangers. However, even in the above-mentioned spiral fin type heat exchanger, the tight binding force between the refrigerant pipe and the fin is small due to the fact that the fin and the refrigerant pipe are not connected by the expansion method, and the circular fin creates a dead space between the adjacent fins. Since the fin heat transfer area cannot be made large, there was a problem that the heat exchange performance was inferior to that of the cross-fin type heat exchanger having the expanded structure.

In order to solve these problems, one fin is provided with one through hole, and a predetermined refrigerant pipe is passed through the through hole and then expanded to obtain a sufficient binding force. A method of bending the tube to obtain an arbitrary heat exchanger shape can be considered.

An object of the present invention is to provide a heat exchanger based on the basic concept thereof, which secures heat exchange performance, minimizes joints, and improves reliability against refrigerant leakage. A second object of the present invention is to increase the degree of freedom in designing the heat exchanger by using the minimum required fin structure as one unit.

[0009]

In order to achieve the above object, one or a plurality of long refrigerant tubes are arranged in parallel, and a plurality of refrigerant tubes are arranged in parallel in the vertical direction of the refrigerant tubes at a predetermined interval. In a cross fin type heat exchanger composed of one fin, only one refrigerant pipe is in contact with one independent fin. This independent fin is preferably a quadrangle in order to maximize the heat transfer area, but may be made circular without any directivity in order to improve productivity even if the heat transfer performance is somewhat sacrificed. It is possible.

Alternatively, in order to increase the heat transfer area or to prevent the adjacent fins from overlapping with each other, one or more of the independent fins are folded back. On the other hand, if you want to increase the heat transfer area only at a specific location compared to other locations, use a fin structure in the width direction that is wider than the interval between long refrigerant tubes arranged in parallel, so that adjacent refrigerant tubes It is also possible to adopt a structure in which the fins joined to each other overlap each other for a predetermined length.
Alternatively, for the purpose of reducing ventilation resistance, a predetermined gap is provided between fins joined to adjacent refrigerant tubes in a predetermined heat exchange area.

Further, in order to secure a heat exchange area on a predetermined plane, an originally linear refrigerant pipe is bent at a predetermined position an arbitrary number of times in one plane. With this basic structure, it is possible to bend at any point, so the length of long refrigerant tubes arranged in parallel can be set arbitrarily, and the number of fins is set according to the length of each refrigerant tube. It has a joined heat exchanger structure. In this structure, for the purpose of improving the productivity, the bending portion is configured by a combination of the same minimum bending radius and an arbitrary straight portion. Further, by applying the present method three-dimensionally, the structure is such that a heat exchange area of a predetermined space having a predetermined plane and a predetermined depth direction is secured. Furthermore, the degree of freedom in design is improved by providing a structure in which fins are spaced at arbitrary intervals.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to FIGS.

FIG. 1 is a perspective view showing a cross fin type heat exchanger H which is an embodiment of the present invention. In FIG. 1 (a), the refrigerant pipe P has eight straight portions Ps (not shown because they are partially shaded by the fins F) and seven bent portions Pc1 to Pc.
It is composed of c7 and is folded back alternately to form a meandering shape in the same plane. In the straight portion Ps of the refrigerant pipe P, fins F for heat radiation are vertically arranged side by side with the refrigerant pipe P at regular intervals, and only one refrigerant pipe P contacts one independent fin F. It is characterized by doing.

FIG. 1B is a variation of the embodiment of the present invention shown in FIG. 1A, and has a structure in which the pitch interval of the fins F joined to the straight portion Ps of the refrigerant pipe is arbitrarily set.

In the embodiment of FIG. 1 of the present invention, the fin F
As for the contact between the refrigerant pipe P and the refrigerant pipe P, there are a pipe expansion system in which the diameter of the refrigerant pipe P is expanded by internal pressure or mechanical contact, or a joining system by external factors such as welding, brazing, bonding, and painting.
The refrigerant pipes P and the fins F are mainly made of a metal having high thermal conductivity such as copper, aluminum and alloys thereof, but may be made of iron, an alloy thereof and a resin. The refrigerant pipe P and the fin F may be made of the same material or different materials. Further, a structure in which the fin F is joined to the bent portion Pc of the refrigerant pipe P can be designed.

FIG. 2 is a perspective view showing another embodiment of the embodiment of the present invention shown in FIG. In FIG. 2A, the refrigerant pipe P has eight straight portions Ps (not shown because they partially shade the fins F) and seven bent portions Pc1 to Pc.
It is composed of c7 and is folded back alternately to form a meandering shape in the same plane. In the straight portion Ps of the refrigerant pipe P, fins F ′ for heat dissipation are vertically arranged side by side with the refrigerant pipe P at regular intervals, and only one refrigerant pipe P contacts one independent fin F. is doing. Since the fins F ′ have a circular shape, the fin F ′ has no directionality when the fins F ′ are attached to the refrigerant pipe P, and productivity can be improved as compared with a heat exchanger in which the rectangular fins F are joined.

FIG. 2B shows an embodiment in which the fin F in FIG. 2A is hexagonal. In this case,
2A shows an intermediate property between the maximum heat transfer area and the maximum productivity in FIG. 2A, and the fin F may have any shape in consideration of the balance between the heat transfer performance and the productivity. It can be designed. The present invention is also applicable to a structure in which the fin F itself is provided with a slit slit or a mountain-shaped bent portion to improve the heat exchange performance of the fin F itself.

FIGS. 3 and 4 are partial perspective views showing another embodiment of the present invention and showing a variation of the embodiment of the present invention shown in FIG. In FIG. 3, the refrigerant pipe P is composed of the linear portions Ps1 and Ps2 of the refrigerant pipe and the bent portion Pc of the refrigerant pipe, and the fins F for heat dissipation are fixed in the linear portions Ps1 and Ps2 of the refrigerant pipe. The refrigerant pipes P are vertically arranged side by side at intervals of, and the structure is such that only one refrigerant pipe P contacts one independent fin F. The fin F includes a refrigerant pipe contact portion Fh and two bent portions Ff. By configuring the fins F as shown in FIG. 3, the heat transfer area of the fins F in a limited area can be increased, and in addition, the linear portion Ps of the refrigerant pipe can be increased.
The fin F that comes into contact with 1 and the linear portion Ps of the refrigerant pipe adjacent to the fin F
The fins F that come into contact with 2 do not overlap, and by any chance,
The fin F when the contact between the refrigerant pipe P and the fin F becomes loose
It has the effect of preventing the rotation. By continuously arranging one embodiment of the present invention shown in FIG. 3, as shown in FIG. 1, it is possible to form a planar heat exchanger structure using a refrigerant pipe P processed in a meandering shape.

FIG. 4 is a perspective view showing an embodiment of the present invention when it is necessary to partially narrow the gap between the fins F in view of the performance of the heat exchanger. Straight part P of four refrigerant tubes
The bent portions Pc1, Pc2, and Pc3 are provided so that s becomes parallel, and the width of the fin F joined to the linear portion Ps of the refrigerant pipe is larger than the pitch interval between the linear portions Ps of the refrigerant pipe. It is a thing. Therefore, there is a portion Fo in which the fins F overlap each other, and a portion is provided for heat exchange at a density that is twice the pitch interval of the fins F attached to the refrigerant pipe P. By arranging one embodiment of the present invention shown in FIG. 4 continuously, a planar heat exchanger structure using a refrigerant pipe P processed in a meandering shape can be obtained as shown in FIG.

In the heat exchanger shown in FIGS. 1 to 4, a plurality of refrigerant pipes P are divided into a straight portion Ps and a bent portion Pc, and a plurality of refrigerant pipes P are manufactured. It is also possible to connect the straight line portion Ps and the bent portion Pc to each other, but if it is desired to minimize the number of joints in the refrigerant passage such as when using a flammable refrigerant, first, a long straight pipe refrigerant is used. By the method of forming the linear portion Ps and the bent portion Pc of the refrigerant pipe by attaching the fins F to a predetermined portion of the pipe P with a predetermined number of pitch intervals and then bending the fin P in a predetermined direction at a predetermined portion of the refrigerant pipe P. It is also possible to produce.

In this case, the pitch interval between the linear portions Ps of the refrigerant tubes is set to be larger than the width of the late fins F, and the fins F that are in contact with the linear portions Ps of the adjacent refrigerant tubes are provided with a predetermined distance. Spaces of intervals can also be provided.

FIG. 5 shows a perspective view of an embodiment in which the present invention is three-dimensionally constructed. The flat heat exchanger H shown in FIGS. 1 to 4 has a linear portion Ps of the refrigerant pipe at a predetermined position B.
It is a heat exchanger H that is bent in an L shape at 0 degrees, enables heat exchange in a three-dimensional space, and has a structure with improved heat exchange efficiency. FIG. 5A shows an embodiment in which fins F are continuously joined to the L-shaped bent portion B of the refrigerant pipe P.
(B) is an embodiment of the refrigerant pipe P in which the fin F is not attached to the L-shaped bent portion B ′ of the refrigerant pipe P. Figure 5 shows the heat exchange efficiency
The heat exchanger of the embodiment shown in (a) is higher, and the productivity is higher in the heat exchanger of the embodiment shown in FIG. 5 (b). In any case, in consideration of the balance between heat exchange efficiency and productivity, a heat exchanger structure of an intermediate type between those shown in FIGS. 5A and 5B can be used. The L-time bent portion B of the refrigerant pipe P may be provided at a plurality of locations, and the angle may be other than 90 degrees. As described above, there is flexibility in that the heat exchanger H of the present invention can be formed into a shape that fits the mounting space of the product.

FIG. 6 is a perspective view showing another embodiment in which the present invention is three-dimensionally constructed. The refrigerant pipe P is composed of 16 straight portions Ps, 7 bent portions Pc1 to Pc7, and 8 bent portions B at L time. 16 straight parts P
A predetermined number of fins F are joined to s at predetermined pitch intervals. Here, each linear portion of the refrigerant pipe P is provided with an arbitrary length, and as shown in FIG. 6, the length of the linear portion Ps on the left side of the heat exchanger H is La, and the length of the linear portion Ps on the right side is La. The length is arbitrarily set as Lb. Thereby, for example, when another component is to be mounted on the straight portion Ps side of the length La, it is possible to form the heat exchanger H in a shape avoiding it. In particular, when the structure of the refrigerant pipe P is a seamless shape, by freely setting the positions of the bent portion Pc and the L-shaped bent portion B, the heat exchanger H having a free shape can be obtained.
Can be provided.

FIG. 7 is an explanatory view showing the structure of the heat exchanger of the present invention in which the bent portion Pc of the refrigerant pipe P can be flexibly set. FIG. 7A shows that the pitch interval Pa between the straight line portions Ps of the refrigerant pipe to which the fins F are joined is
An example is shown in which the bending radius Ra of the bent portion Pc of the refrigerant pipe is equal to twice the bending radius Ra. Further, in FIG. 7 (b), the pitch interval Pb between the straight portions Ps of the refrigerant pipe to which the fins F are joined is smaller than twice the bending radius Rb of the bent portion Pc of the refrigerant pipe.
An example in the case of only large is shown. As shown in the embodiment of FIG. 7A, when the bending radius Ra and the pitch interval Pa between the linear portions Ps of the refrigerant pipe are set, each time the pitch interval Pa between the linear portions Ps of the refrigerant tube changes, The bending radius Ra also changes, and the bending die forming the bending radius Ra must be replaced every time there is a design change, resulting in a large burden of equipment costs. On the other hand, as shown in the embodiment of FIG. 7B, when the bending radius Rb is fixed and the pitch interval Pb between the linear portions Ps of the refrigerant pipe changes, the minute linear portion S
By adopting a structure in which only the distance b is controlled, it is sufficient to prepare a bending die having a minimum bending radius Rb that can be considered in the design stage, which is effective in reducing the equipment cost. In addition,
The minute straight line portion Sb does not necessarily have to be a straight line, and the same effect can be obtained with a bent structure. Further, this structure of the present invention is applicable not only to the bent portion Pc of the refrigerant pipe but also to the L-shaped bent portion B of the refrigerant pipe.

FIG. 8 is a perspective view showing a third embodiment when the present invention is three-dimensionally constructed. The embodiment of the present invention shown in FIG. 1 is a heat exchanger H having a structure in which a refrigerant pipe P is formed in the same plane and fins F are arranged two-dimensionally (two-dimensionally). A heat exchanger H according to another embodiment of the present invention shown in FIG. 8 includes a straight portion Ps of the refrigerant pipe, bent portions Pc1 to Pc4 bent in the same plane, and a bent portion Pc ′ (others) bent in the depth direction. The bent portion bent in the depth direction is formed by a not-shown), and has a three-dimensional (three-dimensional) shape heat exchanger structure. Also in this embodiment, the refrigerant pipe P can be manufactured with a seamless structure, the length of the straight portion Ps of the refrigerant pipe, the pitch interval between the bent portions Pc and Pc ′,
Also, the pitch interval of the fins F can be arbitrarily designed and manufactured in the same manner as in the above-described embodiments.

FIG. 9 is a partial perspective view of a refrigerator equipped with the heat exchanger H of the present invention. This figure shows the lower part of the refrigerator when viewed from the back side, and shows a structure in which a refrigerant condensing cycle system is mounted in a space surrounded by side plates M1, M2, a bottom plate M3, and an evaporating dish E. The refrigerant pipe P according to the present invention
The heat exchanger H constituted by the fins F is configured to pass the refrigerant compressed by the compressor C through the refrigerant pipe P and radiate the heat in the heat exchanger H. The amount of heat radiated in the heat exchanger H is flown to the outside by forced convection of air caused by the fan V.

The heat exchanger of the present invention can be applied not only to the condensation cycle on the back of the refrigerator shown in FIG. 9 but also to the evaporation cycle inside the refrigerator, the heat exchanger for air conditioners, the heat exchanger for refrigerators and dehumidifiers. Is.

According to the above-described embodiment, it is possible to provide a heat exchanger which maintains the heat exchange performance and the heat transfer performance as compared with the conventional type heat exchanger while minimizing the joints and improving the reliability against refrigerant leakage. Is. In addition, by setting the minimum required fin structure as one unit, the degree of freedom in designing and manufacturing the heat exchanger can be increased.

[0029]

EFFECTS OF THE INVENTION The present invention has the effect of providing a heat exchanger having a heat-sealing performance higher than that of a conventional heat exchanger, the number of joints being minimized, and the hermetic reliability being improved. As a result, the product reliability can be improved even when a hydrocarbon-based flammable refrigerant is used. In addition, the minimum required fin structure is set as one unit, and the minimum bending radius and an arbitrary straight line portion are combined and three-dimensionally bent, so that a heat exchanger of any shape can be manufactured, and the degree of freedom in design is high. There is an effect that a heat exchanger can be provided.

[Brief description of drawings]

FIG. 1 is a perspective view showing a cross fin type heat exchanger according to an embodiment of the present invention.

FIG. 2 is a perspective view showing another embodiment in one example of the present invention.

FIG. 3 is a partial perspective view showing a variation of the embodiment of the present invention.

FIG. 4 is a partial perspective view showing a variation of the embodiment of the present invention.

FIG. 5 is a perspective view of an embodiment when the present invention is three-dimensionally configured.

FIG. 6 is a perspective view showing another embodiment when the present invention is three-dimensionally configured.

FIG. 7 is an explanatory view showing the structure of the heat exchanger of the present invention when the bent portion of the refrigerant pipe can be flexibly set.

FIG. 8 is a perspective view showing a third embodiment when the present invention is three-dimensionally configured.

FIG. 9 is a partial perspective view of a refrigerator equipped with the heat exchanger of the present invention.

FIG. 10 is a view showing a refrigerant pipe in which band-shaped fins are spirally wound, which is a conventional technique.

[Explanation of symbols]

F ... Fin, P ... Refrigerant tube, H ... Heat exchanger, Pc ... Bent portion of refrigerant tube, Ps ... Straight portion of refrigerant tube, B ... L-shaped bent portion of heat exchanger.

Continued front page    (72) Inventor Tsuyoshi Kubota             800 Tomita, Ohira-cho, Shimotsuga-gun, Tochigi             Hitachi Co., Ltd., Cooling & Heat Division (72) Inventor Toshiyuki Amimoto             4-6 Kanda Surugadai, Chiyoda-ku, Tokyo             Within Hitachi, Ltd.

Claims (11)

[Claims] 1. A cross fin type heat exchanger comprising a long refrigerant pipe in which one or a plurality of pipes are arranged in parallel, and a plurality of fins arranged in parallel with the refrigerant pipe in parallel at a predetermined interval, A heat exchanger characterized in that only one refrigerant pipe is in contact with one independent fin. 2. A cross fin type heat exchanger comprising a long refrigerant pipe in which one or a plurality of pipes are arranged in parallel and a plurality of fins arranged in parallel at a predetermined interval in the vertical direction of the refrigerant pipe. The heat exchanger according to claim 1, wherein the single independent fin has a rectangular shape or a circular shape. 3. A cross fin heat exchanger comprising one or more long refrigerant pipes arranged in parallel and a plurality of fins arranged in parallel at a predetermined interval in the vertical direction of the refrigerant pipes. The heat exchanger according to claim 1, wherein one or more independent fins are folded back at one or more locations. 4. A long refrigerant pipe in which a plurality of pipes are arranged in parallel,
In a cross fin type heat exchanger consisting of a plurality of fins arranged in parallel at a predetermined interval in the vertical direction of the refrigerant pipe,
A heat exchanger characterized by a fin structure in the width direction wider than the interval between long refrigerant tubes arranged in parallel, so that fins joined to adjacent refrigerant tubes overlap each other for a predetermined length. . 5. A long refrigerant pipe in which a plurality of pipes are arranged in parallel,
In a cross fin type heat exchanger consisting of a plurality of fins arranged in parallel at a predetermined interval in the vertical direction of the refrigerant pipe,
Originally one linear refrigerant pipe at a predetermined location 1 times
The heat exchanger according to claim 1, wherein the heat exchanger has a structure in which a heat exchange region of a predetermined plane is secured by bending in a plane. 6. A long refrigerant pipe in which a plurality of pipes are arranged in parallel,
In a cross fin type heat exchanger consisting of a plurality of fins arranged in parallel at a predetermined interval in the vertical direction of the refrigerant pipe,
The heat exchanger according to claim 1, wherein the heat exchanger has a structure in which a predetermined gap is provided between fins joined to adjacent refrigerant pipes in a predetermined heat exchange region. 7. A long refrigerant pipe in which a plurality of pipes are arranged in parallel,
In a cross fin type heat exchanger consisting of a plurality of fins arranged in parallel at a predetermined interval in the vertical direction of the refrigerant pipe,
The heat exchange according to claim 1, characterized in that the lengths of the long refrigerant tubes arranged in parallel are arbitrary, and the fins are joined in an amount corresponding to the length of each refrigerant tube. vessel. 8. A long refrigerant pipe in which a plurality of pipes are arranged in parallel,
In a cross fin type heat exchanger consisting of a plurality of fins arranged in parallel at a predetermined interval in the vertical direction of the refrigerant pipe,
Originally one linear refrigerant pipe at a predetermined location 1 times
When bending in a plane to secure a heat exchange area of a predetermined plane, the interval between the refrigerant pipes is set to an arbitrary structure by a combination of the same minimum bending radius and an arbitrary straight line portion. Item 5. The heat exchanger according to item 5. 9. A long refrigerant pipe in which a plurality of pipes are arranged in parallel,
In a cross fin type heat exchanger consisting of a plurality of fins arranged in parallel at a predetermined interval in the vertical direction of the refrigerant pipe,
The structure is characterized in that a single originally linear refrigerant pipe is bent at an arbitrary number of times in an arbitrary direction at a predetermined location to secure a heat exchange region of a predetermined space having a predetermined plane and a predetermined depth direction. The heat exchanger according to claim 1. 10. A cross fin type heat exchanger comprising one or a plurality of long refrigerant pipes arranged in parallel and a plurality of fins arranged in parallel at a predetermined interval in the vertical direction of the refrigerant pipes. The heat exchanger according to any one of claims 1 to 9, wherein the fins have an arbitrary interval. 11. A refrigerator, an air conditioner, and other refrigeration application products, which are equipped with the heat exchanger according to any one of claims 1 to 10 as a condenser and an evaporator.