JP2824308B2 - Method for manufacturing header pipe, method for connecting header pipe and tube, and connection structure for header pipe and tube - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for manufacturing a header pipe useful for a heat exchanger used as a condenser for various cooling systems, a radiator for a vehicle, and the like, and a connection between the header pipe and a tube. The present invention relates to a method and a connection structure between a header pipe and a tube.

(Prior Art) Conventionally, a heat exchanger of this type shown in FIG. 4 is known. The heat exchanger includes a pair of header pipes 21 arranged in parallel, a plurality of tubes 22 for flowing a heat exchange medium, which are erected at predetermined intervals in the vertical direction between the header pipes 21, and Each of the tubes 22 and the heat radiation fins 23 is provided with a reinforcing member 24 at the lowermost position thereof.

The header pipe 21 is made of an aluminum welding pipe as shown in FIG. 5 and has a plurality of connection holes 21a to which the tubes 22 are connected in a communicating state on its outer peripheral surface, and has upper and lower openings. Sealed by lid 21b. Although not shown, one of the two header pipes is provided with an inlet through which a heat exchange medium such as a refrigerant or brine flows in, and the other is provided with an outlet through which the heat exchange medium flows out.

The tube 22 is formed of a straight pipe having a flat shape, and both ends thereof are inserted into the connection holes 21a of the header pipes 21, and the members are joined by brazing or the like.

The heat absorbing and dissipating fins 23 are formed of corrugated fins that are curved in a waveform, and upper and lower ends thereof are joined to the tube 22 by brazing or the like.

The manufacture of the above-mentioned heat exchanger is performed as follows.

First, a welding pipe having a predetermined length to be the header pipe 21 is prepared, and a plurality of connection holes 21a having a shape substantially matching the outer shape of the tube 22 are formed at predetermined intervals in the axial direction on the outer peripheral surface of the welding pipe. Separately, the tube 22 and the heat absorbing and dissipating fins 23 are sequentially stacked, and both ends of the tube 22 are inserted into the connection holes 21a of the header pipes 21. They are joined by contact.

(Problems to be solved by the invention) However, in the conventional heat exchanger, the header pipe
Since the connecting hole 21a for the tube is formed by post-processing on the outer peripheral surface of the welded pipe that becomes 21, the manufacturing cost of the header pipe itself is reduced due to the necessity of special jigs and tools for processing. In addition to being expensive, it is difficult to form the connection hole 21a at a predetermined position on the outer peripheral surface of the circular tube.
However, there is a problem that the insertion and connection of the cable are easily hindered.

The present invention has been made in view of the above problems, and a first object is to provide a method for manufacturing a header pipe having a connection hole advantageous for insertion and connection of a tube, and a second object is to provide a method for manufacturing the same. An object of the present invention is to provide a connection method between a header pipe and a tube, which can accurately connect the tube to the header pipe, and a connection structure thereof.

(Means for Solving the Problems) In order to achieve the first object, in claim (1), in a method for manufacturing a header pipe in which tubes for flowing a heat exchange medium are connected in a communicating state, the header pipe is used. A connecting hole is formed in a flat plate, and each edge in the width direction is bent to form a joint piece having a predetermined width. Then, the flat plate is bent into a tubular shape to join the joint pieces to each other.

In order to achieve the second object, in claim (2), a header pipe having a plurality of connection holes on an outer peripheral surface, and a heat exchange medium for flowing a heat exchange medium connected by inserting an end into the connection hole of the header pipe. In the connection method with the tube, after drilling a connection hole substantially matching the cross-sectional shape of the tube in the flat plate serving as the header pipe, inserting the end of the tube into the connection hole, and then bending the vertically long flat plate into a tube. I have.

In order to achieve the second object, in claim (3), a header pipe having a plurality of connection holes on an outer peripheral surface;
In a connection structure with a tube for flowing a heat exchange medium connected by inserting an end into a connection hole of the header pipe, a flat plate having a connection hole substantially matching the cross-sectional shape of the tube is bent into a tubular shape. And the inner peripheral edge of the connection hole is pressed against the outer peripheral surface of the tube by deformation of the connection hole when the flat plate is bent.

(Operation) According to the manufacturing method described in claim (1), the connection hole for the tube is formed in the flat plate before the flat plate is bent into a tubular shape, so that the connection hole can be easily processed. Can be performed with high accuracy. In addition, since the joining pieces formed on the edges in the width direction of the flat plate are joined to each other, the joining can be performed with a wide contact area.

According to the connection method described in claim (2), when the flat plate is bent into a tubular shape after the end of the tube is inserted into the connection hole, the inner peripheral edge of the connection hole curved at the time of bending is pressed against the outer peripheral surface of the tube. Thus, the tube is fixed (temporarily fixed) to the header pipe side.

Furthermore, according to the connection structure of the third aspect, the tube is fixed (temporarily fixed) by the inner peripheral edge of the connection hole that is deformed when the flat plate is bent into a tubular shape.

(Example) FIG. 1 is a perspective view of a heat exchanger to which the present invention is applied.

The heat exchanger includes a pair of header pipes 1 arranged in parallel, a plurality of tubes 2 for flowing a heat exchange medium, which are erected at predetermined intervals in the vertical direction between the header pipes 1, Each of the tubes 2 and the heat absorbing and dissipating fins 3 is provided with a reinforcing member 4 at the lowermost position thereof.

The header pipe 1 is formed by bending a vertically long aluminum flat plate having a brazing material clad on both surfaces or one surface thereof into a tubular shape. As shown in FIG. 2, each of the header pipes 1 has joining pieces 1a and 1b each having a predetermined width at each edge in the width direction, and the joining pieces 1a and 1b come into surface contact with their inner surfaces. Brazed. A holding portion 1c having an L-shaped cross section is formed along an edge of one of the joining pieces 1a, and the other joining piece 1b is held by the holding portion 1c. Further, on the outer peripheral surface of each header pipe 1, a plurality of connection holes 1d to which the tubes 2 for flowing the heat exchange medium are connected in a communicating state are formed at predetermined intervals in the axial direction.
Furthermore, each header pipe 1 has upper and lower openings with lids 1e.
Is sealed by. Although not shown, one of the two header pipes 1 is provided with an inlet through which a heat exchange medium such as a refrigerant or brine flows in, and the other is provided with an outlet through which a heat exchange medium flows out. I have.

The tube 2 is a straight pipe having a flat shape. Both ends of the tube 2 are inserted into connection holes 1d of the header pipes 1 and the portions are brazed.

The heat absorbing and dissipating fins 3 are corrugated fins curved in a wave shape, and upper and lower ends thereof are brazed to the tube 2.

Here, a method of manufacturing the header pipe 1 will be described with reference to FIG.

First, as shown in FIG. 3 (a), a vertically long flat plate K having a predetermined width and a brazing material clad on both surfaces or one surface is prepared.

Next, as shown in FIG. 3 (b), a plurality of connection holes 1d slightly larger than the cross-sectional shape of the tube 2 are formed at predetermined intervals in the longitudinal direction of the elongated plate K by punching or the like. Form. At the same time, each of the edges in the width direction is bent at a right angle to form bonding pieces 1a and 1b having a predetermined width. Further, one joining piece 1a is formed to protrude longer than the other joining piece 1b, and the projecting portion is bent in two steps to form an L-shaped holding portion 1c.

Next, as shown in FIG. 3 (c), the vertically long flat plate K is bent into a tubular shape using a core rod or the like, and the other joining piece 1b is slightly folded inward with respect to one joining piece 1a. The joint piece
1b is pushed between the joining piece 1a and the holding portion 1c. Thereafter, the inner surfaces of the joining pieces 1a and 1b are brought into surface contact and brazed.

Thus, the header pipe 1 shown in FIG. 3D is manufactured. Of course, the joining pieces 1a and 1b may be soldered together with other parts at the time of manufacturing a heat exchanger to be described later, and the projecting portion of the joining piece 1a serving as the holding portion 1c abuts the joining pieces 1a and 1b. After that, it may be bent.

When the heat exchanger shown in FIG. 1 is manufactured using this header pipe 1, a lid 1e, a tube 2, a heat absorbing / radiating fin 3 and a reinforcing member 4 are added to the header pipe 1 shown in FIG. And then throw them into a furnace and braze them all together.

According to the above-described method for manufacturing a header pipe, the connection hole 1d for connecting a tube is formed in the vertical plate K before the vertical plate K serving as the header pipe 1 is bent into a tubular shape. Can be extremely easily and accurately performed. Therefore, there is no need for special jigs and tools unlike the related art for processing the connection hole 1d, so that the manufacturing cost of the header pipe itself can be reduced. Also,
Since the tube 2 can be properly inserted and connected using the connection hole 1d formed with high precision, it is possible to improve the workability of the heat exchanger and to obtain a high-quality heat exchanger. Become.

In addition, since the joining pieces 1a and 1b formed on the respective edges in the width direction of the vertically long flat plate K are brought into face contact with each other and joined, the joining can be performed with a wide contact area, and the joining strength can be improved. Therefore, even when used for a long period of time, cracks and the like do not occur in the joint portion, and the durability of the header pipe 1 can be significantly improved. Also, one joining piece 1a
Since the other joint piece 1b is held by the holding portion 1c formed in the above, the joint between the two joint pieces 1a and 1b can be reinforced to further improve the joint strength.

By the way, the insertion of the tube 2 into the connection hole 1d in the above-described embodiment may be performed at a stage before the vertical flat plate K serving as the header pipe is bent into a circular tube.

That is, first, as shown in FIG. 6 (a), a plurality of connection holes 1d having a shape corresponding to the cross-sectional shape of the tube 2 are formed in the longitudinal direction of the same longitudinal plate K as described above, The joining pieces 1a and 1b are formed at the respective edges, and one joining piece 1a
Is bent in two steps to form the holding portion 1c.

Next, as shown in FIG. 6B, the end of the tube 2 is inserted into the connection hole 1d formed in the vertically long flat plate K.

Next, as shown in FIG. 6 (c), the vertically long flat plate K is bent into a tubular shape. At the time of this bending, the inner peripheral edge of the curved connection hole 1d presses against the outer peripheral surface of the tube 2, and the tube 2 is fixed to the header pipe 1 in a crimped state. The bent joint piece 1b is pushed between the joint piece 1a and the holding portion 1c, and the header pipe 1 is manufactured by brazing the two joint pieces 1a and 1b. Of course, the joining pieces 1a and 1b may be soldered together with other parts at the time of manufacturing a heat exchanger to be described later, and the projecting portion of the joining piece 1a serving as the holding portion 1c abuts the joining pieces 1a and 1b. After that, it may be bent.

According to the connection method described above, the end of the tube 2 is connected to the connection hole.
After being inserted into 1d, the vertically long flat plate K is bent into a circular tube, so that the inner peripheral edge of the connection hole 1d, which curves at the time of bending, is pressed against the outer peripheral surface of the tube 2 to fix the tube 2 to the header pipe 1 side (temporary fixing). When the header pipe 1 is formed, the tube 2 can be reliably positioned with respect to the header pipe 1 at the same time. Thereby, the displacement of the tube 2 can be prevented,
The joining process of the two by brazing can be appropriately performed without any defect.

The sectional shape of the header pipe formed by the vertically long flat plate K is not limited to a circle, but may be a square as shown in FIG. 7, a polygon other than a square, or an ellipse.

In addition, the holding portion formed on one of the joining pieces of the header pipe may not be provided when a sufficient joining area can be obtained for the joining pieces, and as shown in FIG. The character-shaped holder 5 may be fitted to the outside of both joint pieces 1a and 1b to reinforce the joint.

Further, if the connection hole formed in the vertically long flat plate functions as a hole when the vertically long flat plate is bent and joined into a tube, for example, a U-shaped notch is formed at each edge as shown in FIG. The notch may be formed, and the connection hole 1d may be constituted by these notches by bending and joining the elongated plate into a tubular shape. Further, as shown in FIG. 10, a collar portion 1g for inserting and guiding the tube 2 may be formed on the periphery of the connection hole 1d at the same time as the connection hole is processed.

(Effects of the Invention) As described in detail above, according to the manufacturing method of the first aspect, before the flat plate serving as the header pipe is bent into a tube, a connection hole for a tube is formed in the flat plate. Therefore, machining of the connection hole can be performed very easily and with high accuracy. Therefore, there is no need for special jigs and tools for machining the connection holes as in the prior art, so that the manufacturing cost of the header pipe itself can be reduced. In addition, since the insertion and connection of the tube can be appropriately performed using the connection hole formed with high precision, it is possible to improve the manufacturing workability of the heat exchanger and obtain a high-quality heat exchanger. Become.
Furthermore, by joining the joining pieces formed at the edges in the width direction of the flat plate to each other, the joining can be performed with a large contact area and the joining strength can be improved. And the durability of the header pipe can be significantly improved.

Further, according to the connection method described in claim (2), by inserting the end of the tube into the connection hole and then bending the flat plate into a tube, the inner peripheral edge of the connection hole that bends at the time of bending is pressed against the outer peripheral surface of the tube. In this way, the tube can be fixed (temporarily fixed) to the header pipe side, so that when the header pipe is formed, the tube can be reliably positioned with respect to the header pipe at the same time.

Furthermore, according to the connection structure of the third aspect, since the tube is fixed (temporarily fixed) by the inner peripheral edge of the connection hole that is deformed when the flat plate is bent into a tubular shape, displacement of the tube is prevented. It is possible to appropriately perform the joining process of the two by soldering or the like without any defect.

[Brief description of the drawings]

FIG. 1 is a perspective view of a heat exchanger to which the present invention is applied, FIG. 2 is a partially enlarged view of FIG. 1, FIG. 3 is a process diagram showing a method of manufacturing a header pipe, and FIG. FIG. 5 is a partially enlarged view of a conventional header pipe, FIG. 6 is a process diagram showing a method of connecting a header pipe to a tube, and FIG.
8 and FIG. 8 are cross-sectional views of a header pipe showing another embodiment, FIG. 9 is a partial perspective view of the header pipe showing another embodiment, and FIG. 10 is a vertically long view showing another embodiment of the present invention. It is a partial perspective view of a flat plate. In the figure, K: Vertical substrate, 1 ... Header pipe, 1d ...
Connection hole, 2 ... tube.

Claims (3)

(57) [Claims] 1. A method of manufacturing a header pipe in which tubes for flowing a heat exchange medium are connected in a communicating state, wherein a connection hole is formed in a flat plate serving as the header pipe, and each width direction edge is bent. A method for manufacturing a header pipe, comprising: forming a joint piece having a predetermined width; and bending the flat plate into a tube to join the joint pieces to each other. 2. A method for connecting a header pipe having a plurality of connection holes on an outer peripheral surface thereof and a tube for flowing a heat exchange medium connected by inserting an end into the connection hole of the header pipe. A connection between a header pipe and a tube, wherein a connection hole substantially matching the cross-sectional shape of the tube is formed in the flat plate, the end of the tube is inserted into the connection hole, and the flat plate is then bent into a tube. Method. 3. A connection structure of a header pipe having a plurality of connection holes on an outer peripheral surface thereof and a tube for flowing a heat exchange medium connected by inserting an end into the connection hole of the header pipe. The header pipe is formed by bending a flat plate having a connection hole substantially matching with the above into a tubular shape, and the inner peripheral edge of the connection hole is pressed against the outer peripheral surface of the tube by deformation of the connection hole when the flat plate is bent. Characteristic connection structure between header pipe and tube.