JPH0141415B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention mainly relates to a molding method for bending a core portion of an air conditioning heat exchanger.

[Prior art and its problems]

As an example of an air conditioning heat exchanger consisting of a large number of plate fins and tubes, as shown in Figure 3, a compact heat exchanger can be obtained by stacking several layers of elements in the thickness direction and bending them at appropriate positions. was. Conventionally, heat exchanger element 1,
2 was bent and formed as shown in FIG. That is, only one end portions of the heat exchanger elements 1 and 2 are integrated with the common side plate 3 and laminated.
At the bending position, both heat exchanger elements 1 and 2 are held between the mandrel 4 and the holding member 13, and an external force F is applied to both elements 1 and 2 from the direction of the arrow. Then, both elements 1 and 2 are bent around the outer periphery of the mandrel 4 as shown in FIG. However, during this bending process,
Heat exchanger elements 1, 2 are bent at the same time at point B. Therefore, the resultant force required for plastic deformation of each element is concentrated at point B, causing fin collapse at point B. This fin collapse obstructs the flow of cooling air. According to experiments, especially in bends with a small radius of curvature,
The fins were noticeably collapsed, and as a result, the heat exchange performance was reduced.

[Summary of the invention]

Therefore, as a result of various experiments, the present invention aims to provide a forming method in which fin collapse does not occur even if the radius of curvature of bending is small, and the gist thereof is as follows.

That is, a plurality of heat exchanger elements 1 and 2 each having a flat plate shape, with a large number of fins fixed in contact with the outer periphery of each tube, are stacked in the thickness direction of the flat plate. At the same time, only one longitudinal end of the heat exchanger elements 1 and 2 is integrated by a common side plate 3. Furthermore, only the other end in the longitudinal direction of the heat exchanger element 1 located at the outermost one in the stacking direction is restrained so as not to move in that direction. Further, a mandrel 4 is positioned on the outer surface of the heat exchanger element 1 in the stacking direction, and the other end of the heat exchanger element 2 other than the heat exchanger element 1 is pushed continuously or intermittently toward the one end. While moving, each heat exchanger element 1, 2 is guided by the mandrel 4 and bent.

[Embodiments of the invention]

Next, one embodiment of the present invention will be described based on the drawings.

FIGS. 1 and 2 sequentially show the order of forming a heat exchanger core by this method.

First, as shown in Fig. 1, the shorter heat exchanger element 1 is replaced with the longer heat exchanger element 2.
The left ends of both elements 1 and 2 are integrated with a common side plate 3. Independent side plates 5 and 6 are provided at the right end of each side. and,
A bend arm 11 rotating around a pivot point 10 supports the lower surface of the heat exchanger element 2 via a pressing coupling 1. At the same time, the end of the pressing body 8 is brought into contact with the side plate 6 of the heat exchanger element 2. Then, the piston rod of the cylinder 9 is connected to the pressing body 8. Further, the side plate 5 of the heat exchanger element 1 is supported by a support member 7, and the heat exchanger element 1 is restrained from moving both left and right in the figure. Furthermore, the mandrel 4 is brought into contact with the upper surface of the heat exchanger element 1. This mandrel 4 is formed approximately equal to the innermost radius of curvature of the heat exchanger to be bent. Next, as shown in FIG. 2, the bend arm 11 is rotated about the pivot point 10 in the direction of the arrow. At the same time, cylinder 9
The side plate 6 is continuously pushed out to the left (in the direction of the arrow). Then, the heat exchanger element 2 and the heat exchanger element 1 are sequentially plastically deformed and bent around the mandrel 4, respectively. That is, first, only the heat exchanger element 2 is pushed out sequentially from the solid line in FIG. , even if the pressing body 8 is continuously pushed out, it will appear in a very fine range as shown in the figure). Since the heat exchanger element 2 is always sequentially extended to the left, it is plastically deformed at a fixed point A. During this plastic deformation, element 1 is at point A
Since the deformation has already been completed before then, only element B is plastically deformed. Therefore, point A
The reaction force received from the mandrel 4 is sufficient to plastically deform the element 2. Then, just before the element 2 completes its plastic deformation near the point A, the upper part of the element contacts the inner element 2. Then, the inner element 1 begins to plastically deform at point B. At this time, since the element 2 has already been formed to have the same curvature as the mandrel 4 at the point B, only the element 1 is plastically deformed at the point B. Therefore, at point B, only the reaction force due to the plastic deformation of the element 1 is received from the mandrel 4. This will be explained in more detail as follows. First, it is assumed that each element 1 and 2 in FIG. 5 is in a solid line state. Next, it is assumed that the side plate 6 is moved L from the position indicated by the solid line to the position indicated by the chain line by the pressing body 8. Then element 2
moves from the state shown by the solid line to the state shown by the dashed line. Accordingly, point A moves to A ₁ and point B moves to point B ₁ . Here, B and _B1 points are the final curved points of element 2. Next, when element 2 is bent around point A by external force F, _B1 moves to point _B2 . Then, the end of the curved portion of element 2 moves to point _B2 above point B. Therefore, after bending only element 2, the distance between point B and _point B of element 2 is as follows.
It has already been plastically deformed to be equal to the radius of curvature of the mandrel 4. On the other hand, element 1 is in a straight line state at point B. Therefore, only the element 1 is plastically deformed at point B by the external force F.

Therefore, according to the present forming method, the plastically deformed portion of the element 1 and the plastically deformed portion of the element 2 are always different, so that the reaction force positions of the mandrel 4 at each point are dispersed. Therefore, it is possible to prevent the fins from collapsing due to molding of the heat exchanger.

〔Effect of the invention〕

As is clear from the above description, the method for molding a heat exchanger of the present invention has the following configuration.

That is, a plurality of heat exchanger elements 1 and 2 each having a flat plate shape, with a large number of fins fixed in contact with the outer periphery of each tube, are stacked in the thickness direction of the flat plate. At the same time, only one longitudinal end of the heat exchanger elements 1 and 2 is integrated by a common side plate 3. Furthermore, only the other end in the longitudinal direction of the heat exchanger element 1 located at the outermost one in the stacking direction is restrained so as not to move in that direction. Further, a mandrel 4 is positioned on the outer surface of the heat exchanger element 1 in the stacking direction, and the other end of the heat exchanger element 2 other than the heat exchanger element 1 is pushed continuously or intermittently toward the one end. While moving, each heat exchanger element 1, 2 is guided by the mandrel 4 and bent.

The heat exchanger molding method of the present invention has the above configuration and has the following effects.

(1) This forming method is performed by sequentially moving the outer heat exchanger element 2 of the heat exchanger elements to be bent.
It is possible to prevent the fin from collapsing due to external force caused by bending. This is because, in FIG. 5, when the side plate 6 is moved by the pressing body 8 from the position shown by the solid line to the position shown by the chain line, the element 2 is moved leftward from the state shown by the solid line to the state shown by the chain line. When external force F is applied to element 2 in this state,
Only the element 2 deforms plastically around point A. Then, _B1 , which is the final end where plastic deformation has already been completed, moves to _B2 . Then, element 1 begins to plastically deform at point B, and element 2 further plastically deforms near point A. Therefore, based on the plastic deformation of the respective elements 1 and 2, the reaction force received from the mandrel 4 appears distributed at points A and B, and concentration of the reaction force due to the mandrel 4 can be prevented. Conversely, in the conventional molding method, the inner heat exchanger element 1 and the outer heat exchanger element 2 are both deformed at point B, so the resultant force for plastic deformation of both is concentrated at point B. At that point, the fin collapses. However, this method has the effect of preventing the fins from collapsing, improving ventilation, and improving heat exchange performance, as described above.

(2) In addition, this method involves plastically deforming the inner heat exchanger element 1 and the outer heat exchanger element 2 while pushing only the outer heat exchanger element 2 toward one end and moving it. The movement is extremely smooth, and fin collapse at the interface between the heat exchanger elements 1 and 2 can be prevented. That is, as shown in FIG. 5, when the outer heat exchanger element 2 is pushed from the solid line to the chain line, the two heat exchanger elements 1 and 2 become separated, so the pushing is easily performed. obtain. Therefore, fin collapse does not occur on the boundary surface due to pushing.

[Brief explanation of drawings]

Figures 1 and 2 show in order the method of molding a heat exchanger using this method, Figure 3 shows an example of a heat exchanger to which the method is applied, and Figure 4 shows the molding of a conventional heat exchanger. An example of the method is shown, with FIG. 5 being an explanatory diagram showing the molding state of the present invention, and FIG. 6 being an explanatory diagram showing the conventional molding method. 1... Heat exchanger element, 2... Heat exchanger element, 3... Side plate, 4... Mandrel,
5... Side plate, 6... Side plate, 7... Support member, 8... Pressing body, 9... Cylinder, 10... Pivoting point, 11... Bend arm, 12... Pressing coupling, 13 ...Pinching member, F...External force.

Claims (1)

[Claims] 1 A plurality of heat exchanger elements 1 and 2 each having a flat plate shape with a large number of fins fixed in contact with the outer periphery of each tube are stacked in the thickness direction of the flat plate, and the elements 1 and 2 are Only one end in the longitudinal direction is integrated by a common side plate 3, and only the other end in the longitudinal direction of the element 1 located at the outermost side in one of the stacking directions is restrained so as not to move in that direction, and the stacking of the element 1 is A mandrel 4 is positioned on the outer surface of the element 1, and the other end of the element 2 other than the element 1 is continuously or intermittently pushed into the one end side and moved, while each of the elements 1 and 2 is guided to the mandrel 4. A method for forming a heat exchanger, characterized in that the heat exchanger is formed by bending.