JPH10202334A - Bending method for heat exchanger core and temporary mounting plate therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method causing no crushing of a fin in the case of bending a flat plate like heat exchanger core composed of plate fins and a tube through a mandrel. SOLUTION: The thickness of a temporary mounting plate 5 is made thicker than a plate fin 1, made in the thickness less than a small interval between the plate fins 1, and the buckling strength of the temporary mounting plate 5 is formed larger than the buckling strength of the plate fin 1. Then, the temporary mounting plate 5 is inserted between the plate fins 1 from the width direction freely inserting and pulling away. Next, one side in the width direction of the temporary mounting plate 5 is supported by the outer circumference of plural numbers of tubes 2, another side edge is positioned almost matching to the edge of the plate fins 1. Then, the outside force is applied on the heat exchanger core 3, it is guided to a mandrel 4 and bent. Next, the temporary mounting plate 5 is removed from the plate fin 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for bending a heat exchanger core used as an outdoor unit of a heat exchanger for air conditioning and a temporary placing plate for bending the core.

[0002]

2. Description of the Related Art In an outdoor unit of an air conditioner heat exchanger, the entire heat exchanger core is often bent into an L-shape or the like in order to save space and improve a heat radiation area. This bent core is manufactured as follows. That is, first, a large number of plate fins aligned with each other are arranged in parallel with a small gap, and tubes are inserted and fixed in a plurality of through holes of the plate fins, respectively, to form a heat exchanger core having a flat plate shape as a whole. I do. Next, a mandrel was arranged at the bent portion of the heat exchanger core, an external force was applied to the heat exchanger core, and the core was bent by guiding the mandrel to the mandrel.

[0003]

However, in such a conventional heat exchanger core bending method, when an external force is applied to the heat exchanger core and strongly pressed against the mandrel, the plate fins move in the width direction. Buckling occurred, so-called fin collapse occurred, and air could not be circulated in that portion, and the heat exchange efficiency was sometimes reduced. Therefore, an object of the present invention is to provide a bending method in which fins do not collapse during core bending.

[0004]

SUMMARY OF THE INVENTION A method of bending a heat exchanger core according to the present invention comprises the steps of: forming a plurality of tubes 2 in through holes 1a of a number of mutually aligned plate fins 1 arranged in parallel with small gaps;
Is inserted and fixed to form a heat exchanger core 3 having a plate shape as a whole, and a mandrel 4 having an arc-shaped cross section is arranged at an edge of the heat exchanger core 3 in the width direction of the fin 1. An external force is applied to the heat exchanger core 3 to guide the heat exchanger core 3 to the mandrel 4, and the heat exchanger core 3 is bent. The thickness of the fin 1
An elongated temporary placing plate 5 having a larger buckling strength is inserted between the fins 1 so as to be freely detachable from the width direction thereof, and one side of the temporary placing plate 5 in the width direction is placed on the outer periphery of the plurality of tubes 2. The temporary placing plate 5 is supported at a position where the other edge is substantially aligned with the edge of the fin 1.
The mandrel 4 is arranged on the other side, the heat exchanger core 3 is bent, and then the temporary placing plate 5 is removed from between the fins 1. Further, the temporary placing plate for bending the heat exchanger core of the present invention,
A plurality of inverted U-shaped cutouts 5a are formed from one edge of the core 3 so as to be aligned with the plurality of tubes 2 of the core 3, respectively.

[0005]

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is an explanatory perspective view of a temporary placing plate 5 for bending a core according to the present invention and a method of bending the core by using the temporary placing plate. FIG. FIG. 3 is an overall explanatory view of the used state, and FIG. 4 is an explanatory view showing the folded state. This heat exchanger core is used as an outdoor unit of an air conditioner heat exchanger, and tubes 2 are respectively inserted into a plurality of through-holes 1a of a large number of plate fins 1 aligned in parallel with a small gap. The heat exchanger core 3 is inserted and fixed, and has a flat plate shape as a whole.

[0006] Next, the temporary bending plate 5 for core bending used in the core bending according to the present invention has a width of the plate fin 1.
And the height from the upper edge of the plate fin 1 to the tube is slightly shorter than the width of the tube 2 and the height of the tube from the upper edge of the plate fin 1 is equal to the top thereof. Is formed. This inverted U-shaped opening width is slightly larger than the outer diameter of the tube 2. The thickness of the temporary placing plate 5 is significantly larger than that of the plate fins 1 and slightly smaller than the small gap between the plate fins 1 as shown in FIG.
In this example, the plate fin 1 is made of a relatively soft material such as aluminum, and the temporary placing plate 5 is made of a relatively hard material such as a steel plate. The buckling strength of the temporary placing plate 5 is higher than that of the plate fin 1.

The plurality of temporary placing plates 5 thus formed are inserted between the plate fins 1 at appropriate intervals at the core bending position on the upper surface side of the flat heat exchanger core 3 as shown in FIGS. I do. Then, the inner surface top of the inverted U-shaped notch 5a of the temporary placing plate 5 is supported by the tube 2 via the burring portion of the plate fin 1. The burring portion of the plate fin 1 is formed at the edge of the tube through-hole 1 a to specify a gap between the plate fins 1 and to form the plate fin 1 and the tube 2.
And a sufficient contact area. In this example, as shown in FIG. 3, three heat exchanger cores 3, 3a, 3b
In this case, a plurality of temporary placing plates 5 are mounted on the uppermost heat exchanger core 3 having the smallest radius of curvature.
The three heat exchanger cores 3, 3a, 3b are
And the fixing plate 7. Next, a flexible floor plate 8 is placed on the upper surface of the uppermost heat exchanger core 3, and the mandrel 4 is placed via the floor plate 8. The mandrel 4 has an arcuate cross-sectional outer periphery, and an appropriate upper end thereof is attached to a support member (not shown).

Next, the movable plate 6 is rotated clockwise around the mandrel 4 while the mandrel 4 is supported at the position shown in FIG. Then, as shown in FIG.
a and 3b are bent in an L-shape. At this time, the reaction force applied from the mandrel 4 to the heat exchanger core is directly transmitted to the tube 2 via the temporary placing plate 5. Then, the tube 2 is bent to perform a core bending process. Therefore, when the core of the uppermost heat exchanger core 3 having the smallest radius of curvature is bent, the fins do not collapse. When the core bending step is completed in this way, each temporary placing plate 5 is pulled out. For this drawing, as an example, in FIG.
May be extruded from the lower surface side of the device with an appropriate jig.

[0009]

According to the method of bending a heat exchanger core of the present invention, a temporary placing plate 5 having a larger thickness and a larger buckling strength than a plate fin 1 is inserted between the fins 1 and one side thereof is connected to a tube. 2 and the other edge is arranged so as to be aligned with the edge of the plate fin 1, so that the temporary placing plate 5 supports the external force when the heat exchanger core is bent, and Since the transmission is directly to the tube, the plate fins 1 can be prevented from buckling or deforming. Thereby, a high-performance heat exchanger core without fin collapse can be provided. In addition, the temporary placing plate for bending the heat exchanger core of the present invention has a plurality of inverted U-shaped cutouts 5a that match the plurality of tubes 2 of the heat exchanger core 3, so that the temporary placing plate is formed. 5 is efficiently positioned and supported, and becomes a temporary placing plate for core bending with high mass productivity.

[Brief description of the drawings]

FIG. 1 is an explanatory perspective view of a temporary placing plate 5 for bending a core according to the present invention and a method of bending the core using the temporary placing plate 5;

FIG. 2 is a partially enlarged view of the same use state, and is II-
At the II position.

FIG. 3 is an overall explanatory diagram of the same use state.

FIG. 4 is an explanatory view showing the bent state.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Plate fin 1a Through hole 2 Tube 3, 3a, 3b Heat exchanger core 4 Mandrel 5 Temporary placing plate 5a Inverted U-shaped notch 6 Movable plate 7 Fixed plate 8 Base plate

Claims (2)

[Claims] A plurality of tubes (2) are inserted and fixed in through holes (1a) of a large number of plate fins (1) aligned in parallel with a small gap to form a heat exchanger core (3) having a flat plate shape as a whole. A mandrel 4 having an arc-shaped cross section is arranged on an edge of the heat exchanger core 3 in the width direction of the fin 1, and an external force is applied to the heat exchanger core 3 to guide the heat exchanger core 3 to the mandrel 4. In the bending method of the heat exchanger core, the heat exchanger core 3 is bent, the plate thickness is larger than the fins 1, the plate thickness is smaller than the small gap between the fins 1, and An elongated temporary placing plate 5 having a large bending strength is inserted between the fins 1 so as to be freely inserted and removed from the width direction, and one side in the width direction of the temporary placing plate 5 is supported on the outer periphery of the plurality of tubes 2. With the other edge And a position substantially aligned with the first edge, the mandrel 4 on the other side of the temporary placement plate 5
And bending the heat exchanger core 3, and then removing the temporary placing plate 5 from between the fins 1. 2. The temporary placing plate 5 used in the method for bending a heat exchanger core according to claim 1, wherein a plurality of inverted U-shapes are respectively aligned with the plurality of tubes 2 of the core 3 from one edge thereof. A temporary placing plate for bending a heat exchanger core having a notch 5a.