JP2672463B2 - Method for producing flat tube for heat exchanger - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plurality of fixed length flat tubes which are laminated in the thickness direction with fins interposed therebetween, and a pair of flat tubes which are connected at both ends thereof. And a hollow header, and a method for producing a flat tube for use in a multi-flow or parallel flow type heat exchanger in which a heat exchange medium simultaneously flows through a plurality of flat tubes.

[0002]

BACKGROUND OF THE INVENTION Serpentine type heat exchangers are widely used as condensers in car cooling systems. In this condenser, one tube material is bent in a meandering shape to form a core portion.

On the other hand, in a multi-flow or parallel-flow type heat exchanger, a plurality of tubes are arranged between a pair of hollow headers, and both ends of the tubes are fluidly connected to the headers. is there. This multi-flow type heat exchanger is compact, has good heat exchange performance, and has little heat exchange medium side pressure loss. Therefore, its use is increasing.

For example, the tube in this multi-flow type heat exchanger is formed by extruding a long flat tube material by using an extrusion equipment, and stretching and predetermined treatment by a device cooperating with the extruder. After that, the long tube material is manufactured by cutting the long tube material in a predetermined length unit.

[0005]

This process is disadvantageous in that each extruded strip must be of a predetermined length no longer than allowed in the limited floor space around the extrusion equipment. Is. When this long flat tubing is cut into predetermined length tubing, the ends that are shorter than the predetermined length must be discarded. Therefore, it has been impossible to efficiently manufacture a tube from a long tube material.

An object of the present invention is to provide a method for producing a flat tube for a heat exchanger capable of producing a flat tube for a heat exchanger with high efficiency, high accuracy and low production cost.

[0007]

SUMMARY OF THE INVENTION According to the present invention, a plurality of fixed length flat tubes are laminated and arranged in the thickness direction with fins interposed therebetween, and both ends of these flat tubes are connected to each other. A method for producing a flat tube having a pair of hollow headers, wherein the heat exchange medium is made to flow through a plurality of flat tubes at the same time, and is used for a heat exchanger, which is wound around an uncoiler. A movable clamp attached to a movable stand, which is arranged in front of the uncoiler and is reciprocally moved with a predetermined stroke, clamps the long flat tube material in the forward movement process of the stand, while in the backward movement process of the stand. Is unclamped so that a fixed length drawing step for drawing a predetermined length corresponding to the stroke and the front of the stand are performed. During dynamic process, characterized in that it comprises a cutting step of cutting the elongated flat tube material by cutting blades provided in the stand located in front than the clamp.

In the above manufacturing method, a stretcher disposed between the uncoiler and the fixed clamp further applies tension to the long flat tube material unwound from the uncoiler to perform work hardening. It is desirable to add a bending step and a straightening step of straightening the bending of the stretched long flat tube material by a straightening device arranged between the stretcher and the fixed clamp.

Further, in the above-mentioned manufacturing method, the cut tube material is further fed into a press machine for finish processing, and the steps (a) to (d) are sequentially carried out to finally obtain a predetermined product. It is preferable to finish the flat tube in size and shape.

(A) A flattening step of repeatedly bending the tube material in a wavy shape and then straightening it into a straight state; (b) A finishing cutting step of cutting off both ends of the tube material to properly finish the dimension; (c) Tube A sizing step in which both ends of the material are swaged to form insertion ends having a reduced cross-sectional area at the ends; (d) Again, a flattening step similar to the step (a) is performed. Flattening process.

[0011]

Embodiments of the present invention will be described below with reference to the drawings.

1 to 4 show a heat exchanger used as a condenser for a car air conditioner, wherein (1) is a plurality of tubes arranged in a vertical state in a horizontal state, and (2) is a tube adjacent to the heat exchanger ( 1) Corrugated fins interposed between (1).

The tube (1) is made of a flat extruded material made of aluminum and is so-called a harmonica tube whose interior is divided into a plurality of chambers by a partition wall to enhance heat transfer and pressure resistance. The porous type is used. An electric resistance welded tube may be used instead of the extruded mold material.

The corrugated fin (2) is a tube (1)
It has approximately the same width as and is joined to the tube (1) by brazing. The corrugated fin (2) is also made of aluminum, and it is desirable to use a corrugated fin (2) with a louver cut and raised.

(3) and (4) are left and right headers. Each of these headers (3) and (4) is formed by one aluminum tube having a circular cross section. Tube insertion holes (5) are formed in each of the headers (3) and (4) at intervals along the length direction, and both ends of each tube (1) are inserted into the holes (5); It is firmly connected by brazing. Further, a heat exchange medium inlet pipe (9) is connected to the outer side of the upper end of the left header (3), and a heat exchange medium outlet pipe (10) is connected to the outer side of the lower end thereof.
Lid pieces (8) are attached to the upper and lower ends of the headers (3) and (4), respectively. Further, the left header (3) is provided with partition members (6) at positions above and below the central portion, respectively, and the inside of the header (3) is partitioned into three chambers, while the right header (4) is also substantially divided. A partition member (6) is provided in the central portion, and the inside of the header (4) is partitioned into two chambers.

By the installation of the partition member (6), the circulation circuit of the coolant is formed as shown in FIG. 4; that is, the heat exchange medium passages are the inlet side section (A), the intermediate section (B) (C). ), And also the exit side section (D)
It is divided into four sections. As shown in Figure 4, the coolant flows in four different directions. Furthermore, group (B) has more tubes than groups (C) (D) and group (A) (inlet side section) has more tubes than group (B). That is, the group (A) has a larger heat exchange medium passage sectional area than the group (B) and further has a larger heat exchange medium passage sectional area than the groups (C) and (D).

However, the number of tubes may be gradually reduced from the section (A) to the section (D). Furthermore, assuming that the number of tubes in each section (A) to (D) is the same, the cross-sectional areas of the tubes are from sections (A) to (B), (B) to (C), and (C) to (D). It may be gradually reduced. As a further modification, the intermediate sections (B) and (C) may be omitted; the distribution pattern in that case is called the two-pass method. On the other hand, the above embodiment is called a 4-pass method.
As a further modification, one or more intermediate sections may be added.

The coolant flowing from the inlet pipe (9) into the core flows to the right header (4) of the inlet side section (A) and then reverses to the first intermediate section (B) as shown in FIG. Flows to. The coolant flowing into the left header (3) reverses and flows to the second middle section (C). And the coolant that flowed into the right header (4)
It reverses again and flows to the outlet side section (D), flows into the left header (3), and is discharged from the outlet pipe (10). The coolant is in each section (A), (B), (C),
While circulating (D), heat is exchanged between the coolant and the air flowing through the fins (2). The coolant is gaseous in the inlet section (A), but due to the large passage cross-sectional area of the section (A), efficient heat exchange is performed between the coolant and air. In the section (D), the coolant is in a liquid state and has a small volume, and the section (D) may have a relatively small heat exchange medium passage sectional area as compared with the inlet side section (A). Thus, the coolant flows from the first condensing section (A) to the second section (B), the third section (C), and the fourth subcooling section (D),
During that time, heat can be exchanged smoothly and efficiently.

The partition member (6) is formed by stacking a pair of symmetrical partition plates (122) (113) made of aluminum, and these are connected to each other at their tip portions so that the free end side is moved from the tip side. It has a substantially V-shape in a side view, which is slightly open toward the side.

The partition plates (122) (113) are respectively shown in FIG.
As shown in Fig. 2, the disk-shaped partition parts (122a) (113a) conforming to the inner peripheral shape of the header (3) and the free end side half circumference part of the partition parts (122a) (113a) Formed to have projecting edge portions (122b) (113b) integrally projected outward in the direction and ribs (122c) (113c) connected in a rising manner in a direction opposite to the peripheral edge portion of the edge portion Has been done. Further, one partition plate (122) is tapered from the position inside the partition (122a) to the boundary position with the projecting edge (122b) toward the projecting edge (122b) side. A pair of raised retaining ridges (114) (114) are provided.

An aluminum brazing sheet is used as a raw material sheet used for producing the partition member (6), and a brazing material layer is provided on each opposing surface of the partition plates (122) (113). ing.

As shown in FIG. 2 (a), each of the heat exchanger constituent members has a plurality of tubes (1) arranged in parallel at predetermined intervals, and the ends of the tubes (1) are attached to both ends of the tubes. The headers (3) and (4) are assembled by being inserted into the tube insertion hole (5), and the corrugated fins (2) are inserted and arranged between the tubes (1), and the side plate (12) and the inlet pipe (9) ), The outlet pipe (10) and the like are assembled, and at the same time, the partition member (6) is inserted into the headers (3) and (4) through the slit-shaped openings (11), and the partition parts (122a) (113a). Is arranged in the internal space of the header (3), the protruding edges (122b) (113b) are arranged in the slit-shaped opening (11), and the rib (122c) is arranged.
The heat exchanger assembly is assembled by arranging the (113c) in a state of abutting against the inlet peripheral portion of the opening (11).

When inserting the partition member (6),
As shown in FIG. 1, this is inserted into the header (3) in a state where the free end side is held open with the tip joint part (115) as an axis. As a result, both partition plates (122
) (113), the protruding edge portions (122b) (113b) are elastically brought into contact with the peripheral edge of the slit-shaped opening portion (11), and the partition member (6) with respect to the header (3). The positioning is maintained in the proper arrangement. If both of the protruding edges (122b) (113b) are held in contact with the peripheral edge of the opening (11), the partition member (6) is held in an appropriate arrangement by the frictional action. Therefore, the contact does not necessarily have to be elastic.

Further, the retaining protrusions (114) (114)
Engages with the inner edge of the slit-shaped opening (11), so that the displacement of the partition member (6) in the extraction direction is more reliably prevented. Since the raised portions (114) (114) are formed so as to be inclined toward the free end direction of the partition member (6), they can be smoothly inserted into the header (3).

The heat exchanger assembly, including the side edge butting portions of the header pipes, is joined and integrated with each other by collective brazing in the brazing furnace.
Manufactured into a heat exchanger. Until this brazing implementation,
The partition member (6) is maintained in the proper arrangement state with respect to the header (3), and as a result, the partition member (6) is brazed to the header (3) in the proper arrangement state, so that the partition structure is reliable. Manufactured into a high heat exchanger.

Further, the partition member (6) is made of an aluminum brazing sheet, and both partition plates (122).
Since the brazing filler metal layer is present on the opposing surface of (113), the gap is closed by the brazing filler metal by collective brazing, and the sealing property in the header (3) is kept good. Needless to say, as a method for closing this gap, various methods such as brazing can be used in addition to using the brazing sheet as described above.

Further, as the partition member (6), a pair of partition plates (122) (113) formed in a superposed configuration is adopted, so that compared to the case where ribs are formed on one partition member. As a result, the ribs (122c) (113c) can be made thinner, and therefore the ribs (122c) on the outer peripheral surface of the header (3)
By reducing the protrusion due to (113c), it is possible to manufacture a heat exchanger with high commercial value.

On the other hand, the flat tube (1) is manufactured as follows.

This flat tube (1) is a standard-sized material having a flat cross section made of an aluminum extrusion mold material. As shown in FIG. 1, the upper wall (uw) is connected to the lower wall (dw) by a plurality of reinforcing partitions or walls (rw) to form a so-called "harmonic tube". For example, its width B is 16 mm or 20 mm, and its height H is 2 mm or 3 mm.
It is. In the present invention, equal lengths (eg 2
85-750 mm) short tube is manufactured.

The outline of the method for manufacturing the flat tube according to the present invention is as follows.

The long flat tube material (T) made of extruded aluminum is carried into the processing line shown in FIG. 5 in the state of the coil wound around the uncoiler (401).

In this processing line, the long tube material (T) is pulled out from the uncoiler (401) and introduced into the work hardening station (407). Here, the tube material (T) is made up of multiple bending rolls (429).
It is repeatedly bent in a meandering shape via (430) and is work-hardened.

After that, in a bending correction step, it is corrected to a substantially straight state.

Then, it is sent to the rough cutting step. By this rough cutting, a predetermined length is cut. The roughly cut tube material (T) is sent to a press machine (C) for finishing, and as shown in FIG. 12, the following (a) and (b)
The processing operations of (c) and (d) are performed, and the final flat tube (1) having a predetermined size is finished.

(A) Flattening After the tube material (T) is repeatedly bent in a wavy shape,
It is straightened.

(B) Finish cutting The both ends of the tube material (T) are cut off so that the tube material (T) is properly finished to a specified size. Details of this finish cutting step will be described later with reference to FIG.

(C) Sizing Both ends of the tube material (T) are swaged to form insertion ends having a reduced cross-sectional area.

(D) Flattening The flattening process similar to the above step is performed again,
The flat tube (1) as a final product is finished.

The method of manufacturing the above tube will be described based on an apparatus preferably used for carrying out the method.

In FIGS. 5A and 5B, reference numeral "A" indicates a standard length tube cutting device, reference numeral "B" indicates a conveyer conveyor, and reference numeral "C" indicates a finishing press working device.

This continuous constant length cutting device is generally composed of an uncoiler (401), a movable stand (402) and a drive device (403).
Movable clamp (404); cutting device (405); fixed clamp (406); cutting end holding device (411); stretcher (4)
07); and a straightening device (408).

Most of the tube material (T) is coiled around the uncoiler device (401). The motor provided in the uncoiler assists in unwinding the tube material.

The movable stand (402) arranged at a front position slightly away from the uncoiler (401) moves back and forth along the guide means (413) as shown in FIG.

The drive unit (403) includes a motor (414) and a crank (415). The crank (415) converts the output of the motor transmitted to the movable stand (402) into a linear motion that reciprocates the movable stand back and forth by a predetermined distance.

The movable clamp (404) is attached to the movable stand (40
It is installed in 2) and reciprocates back and forth according to its movement. It includes an upper clamper (417) and a lower clamp base (418), as shown in FIGS. 8 (a) and 9 (b). The clamp base (418) is attached to the movable stand (402). Above that,
It has a guide groove (418a). The air cylinder (419) is
Raise and lower upper clamper (417). The tube material (T) is disposed in the guide groove (418), and the lowered upper clamp (417) and the clamp base (418) sandwich the tube material between them.

Upper clamper (417) and air cylinder
It is preferable to interpose a coil spring (not shown) between (419). The cylinder does not press the tubing (T) directly, but the coil spring does so reasonably and reliably.

The cylinder (419) is a clamper (417)
During the forward movement of the movable stand (402), and keep the original position during the backward movement of the movable stand. Due to the cooperation of these members, the tube material (T) is intermittently unwound from the uncoiler in equal lengths corresponding to the stroke of the movable stand.

A mechanical valve such as a rotary air valve controls the air cylinder (419). This valve causes the cylinder to respond sensitively to the movement of the crank mechanism (415).

As shown in FIGS. 8 (a) and 8 (b), the upper clamper (417) has a projection (421) for preventing the unwound tube material (T) from slipping from the clamper. It has a formed lower surface. This protrusion
(421) extends in the direction crossing the tube material (T),
Most preferably, it is an oblique cross that makes an angle of 45 ° with the tube material (T), which shape prevents the tube material from slipping.

The cutting device (405) for cutting the long tube material (T) is located in front of the movable clamp (404) as shown in FIGS. 5 (a) and 5 (b). , Provided integrally with the movable stand (402). FIG.
(A), (b) and (c) show a cutting device (405) provided with a cutting blade (423) and a cutting block (424).

The cutting blade (423) is of a "cut-off" type and is arranged on the side of the passage path of the tube material (T).

The cylinder 425 operates this cutting blade from the side of the tube material (T) until it "cuts" the tube material. Cutting the flat harmonica tube material (T) in this manner effectively prevents deformation of the cut portion.

The edge of the blade (423) is specially designed,
It has upper and lower concave arc portions and an outwardly projecting central sharp portion (423a) located between them.

The cutting blade (423) is advanced to the projecting position after the forward movement of the movable stand (402) is started. Subsequently, the blade is returned to the retracted position at the end of the forward movement. It is held in the backward return position during the rearward movement of the movable stand (402). In this way, the moving body (4
The tube is cut during the forward movement of 02). Cutting blade (42
The movement of the working cylinder (425) of 3) must be sensitively responded to the reciprocating movement of the movable stand. A mechanical valve may be employed to control the cylinder (425) in conjunction with the operation of the crank mechanism (415) and thus the reciprocating movement of the movable stand.

The cutting block (424) clamps and holds the tube material adjacent to the cutting blade (423) for cutting the tube material (T). The outer peripheral surface of the tube material (T) is firmly covered by the inner surface of the cutting block (424), so that the cutting blade does not deform the tube material near the cutting position. The cutting block (423) clamps the tubing preferably at two points in front of and behind the blade (423).
The clamping of the tube material on the rear side of the blade is precisely positioned by the block. In the tube material behind the blade (423), the cutting block (424) also functions as a fixed blade in pair with the cutting blade.

The clamping of the tube material in front of the blade effectively grips the rear end of the piece cut from the tube material (T). Alternatively, the cutting block (424) is
It may be designed to grip only one of the front and back of the blade. Reference numeral (422) designates a drive cylinder for actuating the cutting block. Mechanical valves may be employed to control the cylinder (422) in conjunction with the operation of the crank mechanism (415).

The fixed clamp (406) is shown in FIG.
As shown in (b) and FIG. 6, the movable stand (402)
And the uncoiler (401) are fixedly installed. Like the movable clamp (404), this fixed clamp also includes an upper clamper driven by a cylinder (427) and a lower base.

Drive Cylinder for Upper Clamper (427)
Is held in the retracted state while the movable stand (402) is moving forward, but is in the advanced state while the movable stand (402) is moving backward. As a result, the fixed clamp (406) does not interfere with the forward movement of the movable stand (402) when pulling the tube material (T) forward, and the rear of the movable clamp (404) mounted on the movable stand. The motion does not push the tubing back backwards. The mechanical valve is
Also here, the cylinder (427) may be employed to control the operation of the crank mechanism (415), and thus the reciprocating movement of the movable stand.

The holding device (411) holds the movable stand (402) so that the tip cut portion of the tube material (T) does not shake while the movable stand (402) moves rearward. This holding device (4
As shown in FIG. 5, 11) is arranged at a predetermined position in front of the movable stand (402).

As shown in detail in FIG. 9, the holding device (411) includes a pair of front and rear thrust bearings (442), (4).
It is equipped with a sliding rod (441) supported by 43). The sliding rod (441) has an axially extending hole (440),
Driven back and forth. A cutting end receiver (444) is attached to the rear end of the sliding rod. The coil spring (445) is attached to the rear bearing (442) and the receiver (4).
44) between the bearings (4)
42) It is designed to be held at a predetermined distance from. A stopper (446) is attached to the tip of the rod (441).

Cutting device (405) on the movable stand (402)
Contacts the receiver (444) during the forward movement process. Then, the cutting device (405) connects the rod (441) to the spring (4
45) Move it forward against the urging force of 45), and move the rod to the forward position as shown in phantom in FIG. When the foremost position is reached, the movable stand (402) moves backward and the spring (445) pushes the rod (441) back. As a result, the tube material (T) is
4) is introduced into the shaft hole (440) of the rod.

The guide (448) is installed in front of the rod (441) coaxially therewith. The fixed length pieces cut from the tube material (T) are successively introduced into the inside thereof. The stretcher (407) that gives tension to the tube material (T) and causes it to undergo work hardening is shown in FIG.
As shown in (a) and (b), the uncoiler (4
It is located in the position between 01) and the fixed clamp (406).

This tensioning stretcher (407)
10 comprises an upper row "UR" consisting of three rollers (429) and a lower row "DR" consisting of two rollers (430), as shown in FIG. The upper roller (429) is arranged in a fixed position at predetermined intervals. Each lower roller (4
30) is placed between adjacent upper rollers (429),
The upper and lower rollers have a zigzag shape. Articulating frame (4) connected to the shaft of the lower roller (430)
32) slides along the guide rods (433), (433). Therefore, the two lower rollers move up and down in synchronization with each other. They usually wait in the lowest position by weight. They move upward when the upward force exceeds a critical force greater than weight.

The tube material (T) is adjusted by adjusting its critical force.
A balancer is preferably equipped to control the tension acting on.

As shown in FIGS. 5 (a) and 5 (b), a straightening device (408) for straightening the bending of the tube material (T).
Is located between the stretcher (407) and the fixed clamp (406).

As shown in FIG. 11, this straightening device is provided with a plurality of pairs of upper rolls (435) and lower rolls 436. Each pair of rolls (435) is spaced from the roll (436) at a distance substantially equal to the thickness of the tubing (T). Each pair is arranged at substantially equal predetermined intervals. Each pair of rolls (435) and (436) is placed slightly higher or lower than the two adjacent pairs, and the tube material (T) passes through each pair with a slight meandering.

In FIG. 5 (a) and (b), reference numeral (437)
Shows a guide roller for feeding the tube material (T) from the uncoiler (401) to a predetermined rear position of the stretcher (407).

Before the cutting device (A) is activated, the tube material (T) is unwound from the uncoiler (401) and passed through the guide roller assembly (437).
7).

Then, the tube material (T) is continuously applied to one roller (429) or (430) in a manner that the lower peripheral surface of each lower roller (430) contacts the meandering tube material.
From the other roller (430) or (429).

This tube material (T) is further provided with a straightening device (4
08) and is guided to the movable clamp (404) via the fixed clamp (406). Following these preparatory steps,
The drive (403) provides a "scale" transfer of tubing (T) that is precisely cut into equal length pieces as previously described.

Specifically, the movable clamp (404) grips the tube material (T) by converting the rearward movement of the movable stand (402) to the forward movement, and at the same time, until the tube material moves forward by a predetermined distance. Causes the fixed clamp (406) to unclamp the tubing.

By the reverse conversion of the movable stand (402) from the forward movement to the backward movement, the movable clamp (404) unclamps the tube material (T) and, at the same time, the fixed clamp.
(406) grips the tube material. Therefore, in the movable stand (402), the tube material (T) is fixed to the clamp (406).
It is smoothly moved backward while it is held in place by. This cycle is repeated intermittently, and the tube material (T) is pulled out by a certain length from the uncoiler. This length corresponds to the stroke on the movable stand.

The cutting blade (423) moves forward during the forward movement of the movable stand (402), whereby the tube material (T) is moved.
Is cut into standard length pieces.

The cut end of the tube material (T) thus provided is introduced into the shaft hole (440) of the rod (441) of the holder (411). As already mentioned, this action is performed by the force of the cutting device (405) against the cutting end receiver (444) of the rod (441). This force is a spring
Move the receiver forward against (445), then
The receiver on the rear side in synchronization with the movable stand (402) on the rear side
Move (444). In this way, the cut end of the tube material (T) is prevented from swinging and deforming.

The supplied piece is pushed forward by the cut end of the tube material, penetrates the rod (441) of the holder (411), and enters the tube guide (448).

As is apparent, pulling out the tube material (T) forward by a predetermined length is not limited to the switching operation of the clamp state between the movable clamp (404) and the fixed clamp (406), but also the movable stand (T). 402)
Exactly repeated. Cutting blades on movable stand (402) (4
23) is a movable clamp that repeats the grip of the tube material (T) to intermittently feed the tube material forward by a predetermined length.
Moves back and forth together with (404). According to the configuration of the present invention, even if the cutting blade (423) is cut at any time during the forward movement of the movable stand (402), it is possible to supply a fixed-size piece from the tube material (T).

This is because the cutting of the tube material (T) is completed before the movable stand (402) reaches the foremost position, so that the movable stand can immediately return to the original position. This feature makes it possible to increase the number of round trips of the movable stand (402) per unit time and further improve the efficiency. In addition, all drive cylinders have crank (4
Since it is controlled by a mechanical valve that responds quickly to (15), more efficient and accurate cutting can be performed. For example, in the apparatus of the embodiment, one piece is cut from the tube material at a rate of 0.84 seconds.

Since the movable stand (402) does not require a temporary stop at the time of turning, it does not adversely affect the accuracy,
It is possible to use the crank mechanism (415) to simplify the entire drive system and reduce the total cost of this device.

The cutting block (424) grips the rear end of the piece cut in front of the cutting blade (423) until the movable stand 2 reaches the front position where the block is free. This provides a smooth transition to the next cycle.

As described above, the tube material (T) pulled out forward by the movable stand (402) exerts inertia in the stretcher (407) to lift the lower roller 30 against their own weight. , The tube material is processed and hardened.

In this way, the strecher (4
By adopting 07), uncoiler (40
Tension treatment can be efficiently applied to the tube material (T) that is intermittently pulled out from 1).

Preferably, a suitable braking force is applied to the anchor (4) which is rotated by the movable stand (402) which moves forward.
It is desirable that the tension of the tube material (T) is kept constant and optimal by applying it to 01).

In addition, the tube material (T) meanders sharply and rapidly around the upper and lower rollers (429) and (430) to perform "work hardening" while the tube is processed. The bend remaining in the material (T) is also corrected.

Passing through the straightening device (408) straightens the tube material (T), and the straightening device (40)
The gentle meandering passage through 8) is not only beneficial for efficient work hardening, but also the tube material (T).
More efficiently straight and its height, ie thickness "
Control H ".

The tube (T) thus supplied to the cutting device (A) is placed on the conveyor (B) through the guide (448). On the way of this conveyor, the tube is centered by the centering device (450) so that the edges thereof are aligned, and the tube is intermittently conveyed to the finishing press (C).

FIG. 13 shows the finishing press "C". First
Section (453) connects each tube (T) to (a) of FIG.
It is made to meander in a shape as shown in 1). Second section (4
54) further meanders them so that their phases are different as shown in (a2). The third section (455) finally presses them straight as shown in (a3). This process is an additional "work hardening" of the tube.
And make them more straightforward.

Another purpose of the finishing press process is to straighten the width and height of each tube. FIG. 13 shows two press die assemblies used in the first and second sections (453) (454). Each assembly is equipped with a lower die (456) and an upper die (457) that cooperate with each other to cause the tube to meander. The assembly also includes a right die (458) and a left die (458) that cooperate with each other to correct the tube width. When the upper die (457) moves downward, the left and right recesses (457a) are respectively moved to the left and right die (458).
Fit the tops of the and press them against each other. Both sides of the tube (T) are thus pressed inward to straighten its width. Regarding the height, the second
Other upper and lower dies in section (457)
(456) also serves this purpose to some extent, but the upper and lower dies in the third section (459) and (4)
60) is mainly corrected.

After the finishing press, the rough cutting ends of each piece from the tube material (T) are trimmed by the "cutting-off" method in the finishing cutting step as shown in FIG. 12 (b).

After that, in the sizing step shown in FIG. 9C, sizing processing or swaging processing is applied to both ends of each piece, and then corrugation is performed in the final flattening step as shown in FIG. Strengthening by processing, and / or final flattening of each tube is performed following the trimming step before the final tube (T) leaves the production line.

In the finish cutting step performed by the press machine (C), both ends of the above-mentioned roughly cut tube material (T) are cut off to finish the tube to a correct specified dimension.

FIG. 14 (a) shows the state before cutting. The pair of upper and lower clampers (470) (471) are at the open position, and the two cutting blades (472) are at both ends of the tube material (T). Standing by at the side of the department.

At the time of cutting, after the tube material (T) is fixed by both clampers (470) (471) as shown in FIG. 8B, the cutting blade (472) is advanced to move both end portions of the tube material. Disconnect at the same time.

Then, as shown in FIG. 13C, the cutting blade (472) advances so as to completely traverse the tube material (T), and separates the scrap (S) from both ends of the tube material (T). . On the other hand, in the sizing process, both ends of the tube material (T) cut to the specified dimension in the above-mentioned finish cutting process are subjected to drawing processing (swaging processing), and the cross-sectional area is reduced toward the tip for insertion. Form the edges.

The steps are shown in order in (a), (b) and (c) of FIG. As shown in these figures,
After the tube material (T) is clamped and fixed by a pair of clampers (490) (491), the sizing die (482) is advanced, and the end of the tube is forcibly pushed into the sizing hole (482a). This forms the insertion end.

In accordance with the above, in the tube manufacturing method of the present invention, the movable clamp is repeatedly moved in the clamped state for each stroke of the movable stand, so that the tube material is intermittently rewound from the uncoiler for a predetermined length. Since the cutting blade cuts the tube material during the forward movement of the movable stand, the movable stand does not need to be stopped at the most advanced position, which increases the number of repeated strokes per unit time and improves the manufacturing efficiency.

In addition, the clamp accurately draws the tubing material a predetermined length during each stroke of the movable stand. The fixed distance provided between the cutting blade and the movable clamp mounted on the movable stand is due to the cutting blade that moves according to the tube material held in place by the clamp.
It has a beneficial effect on very precise cutting of standard length pieces. Therefore, the cutting operation can be performed accurately and at a low running cost.

The heat exchanger is manufactured as follows. That is, both ends of the tube (1) are inserted into the tube insertion holes (5) of the header pipes (3) and (4). When inserting the tube (1), both ends in the width direction of the tube are guided by the guide surfaces (34) at both ends of the tube insertion hole (5) and smoothly inserted, and after insertion, the guide piece (7) of the insertion hole. Guided by the tube (1)
Is plugged straight in. Moreover, the tube (1) is firmly guided by the guide piece (7) even after it is inserted, and there is almost no wobbling in the height direction of the tube (1), and the header pipes (3) (4) and the tube (1) form a right-angled shape. Connected.

After the tubes are inserted, the corrugated fins (2) also made of a brazing sheet are arranged between the adjacent tubes (1) and (1) and outside the outermost tube in an interposing state, and the pipe partition plate insertion hole is provided. After inserting the partition plate (6) into (11) and arranging the upper and lower side plates (12) and (12) outside the outermost corrugated fins and temporarily assembling, these components are brazed in the furnace. Brazing all at once.

After brazing, as shown in FIG.
A sufficient fillet is formed at the connecting portion between the header pipes (3) and (4) and the tube (1), and the header pipe and the tube are firmly joined and integrated without a gap. Further, the outwardly open guide surfaces (34) at both ends of the insertion hole serve as a wax reservoir, and the braze flows in, and the abutting portions of the guide piece (7) and the tube (1) are widely joined to each other for a stronger joint. Guarantee. In addition, fillets are also formed at the abutting portions (36) of the header pipes (3) and (4), and the abutting portions (36) are hermetically joined.
Moreover, since the header pipes (3) and (4) are deformed under pressure at both side edges of the forming plate (30) at the manufacturing stage to be crushed into a continuous thin state, the abutting portion ( Since 36) matches the overlapping state and the brazing material layer (30b) exists between the contact surfaces, the joining of the abutting portions (36) can be more reliably and sufficiently ensured.

Note that (8) and (8) shown in FIG. 2 are upper and lower lid pieces of the header pipes (3) and (4), respectively, and these lid pieces are molded into a cap shape to form the header pipe (3). ) After the molding of (4) and before brazing, it is externally fitted to the end portion of the header pipe, so that the pipe is closed and
It also serves to prevent the opening of the abutting portion of the header pipe due to thermal deformation when the brazing heat is applied. Further, (9) shown in FIG. 2 is a heat exchange medium inlet pipe, and (10) is the same outlet pipe, and these inlet and outlet pipes are brazed together like other parts.

In the embodiments described in detail above, the method for producing a standard tube from the porous flat extruded tube material has been described, but the present invention is not necessarily limited to this. Instead of manufacturing from this type of extruded tube material, it may be manufactured from a long electric resistance welded tube.

[0102]

As described above, according to the tube manufacturing method of the present invention, each stroke of the movable stand causes the movable clamp to repeatedly perform the clamped state, and therefore the tube material is intermittently wound from the uncoiler for a predetermined length. Since the cutting blade cuts the tube material while the movable stand is moving forward, the movable stand does not need to be stopped at the most advanced position, increasing the number of repetitive strokes per unit time and improving manufacturing efficiency. Excuse me.

In addition, the clamp accurately draws the tube material a predetermined length during each stroke of the movable stand. The fixed distance provided between the cutting blade and the movable clamp mounted on the movable stand is due to the cutting blade that moves according to the tube material held in place by the clamp.
It has a beneficial effect on very precise cutting of standard length pieces. Therefore, the manufacturing work of the flat length flat tube can be performed accurately and at a low running cost.

According to a second aspect of the present invention, in the constant length drawing step, a movable clamp attached to a movable stand disposed in front of the uncoiler and reciprocally moved with a predetermined stroke, the uncoiler and the uncoiler. While the movable clamp holds the long flat tube material in the clamped state and the fixed clamp holds the unclamped state in the forward movement process of the stand by the fixed clamp arranged between the stand and the stand, By performing the process by holding the fixed clamp in the clamped state and the movable clamp in the unclamped state in the backward movement process of the movable stand, it is possible to manufacture a more accurately cut flat tube. .

Further, as described in claim 3, a stretcher arranged between the uncoiler and the fixed clamp applies tension to the long flat tube material unwound from the uncoiler to work-harden it. By performing a stretching step, and a straightening device arranged between the stretcher and the fixed clamp, by having a straightening step for straightening the bending of the stretched long flat tube material, The tube material that is intermittently pulled out from the uncoiler for constant length cutting can be continuously and efficiently subjected to work hardening by tension treatment and straightening of the bend remaining in the tube material.

According to a fourth aspect of the present invention, in the stretching step, a plurality of upper rollers arranged at predetermined positions at predetermined intervals and a plurality of vertically supported lower positions between the upper rollers are supported. A lower roller, and the long flat tube material from the uncoiler passes through each roller continuously in a meandering manner in a manner of going around the lower roller. By performing the vertical movement of the side roller against its own weight, it is possible to continuously and efficiently perform the tension treatment on the long tube material that is intermittently pulled out in a limited space.

As described in claim 5, further, the cut tube material is sent to a press for finishing, and (a) flattening for straightening the tube material after repeatedly bending it into a wavy shape. Step; (b) Finish cutting step of cutting off both ends of the tube material to finish correctly to a specified dimension; (c) Inserting the tube material at both ends by swaging to reduce the cross-sectional area. A sizing step for forming an end portion; (d) A flat tube having a final predetermined size and shape is obtained by sequentially performing each step of the final flattening step in which the same flattening step as the step (a) is performed again. If it is finished, it is possible to preferably manufacture a standard length flat tube for a heat exchanger having a more accurate size and shape.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a heat exchanger using a tube manufactured by the method of the present invention in which a header pipe and a tube are separated from each other.

2 (a) is a front view of the heat exchanger shown in FIG. 1,
Similarly, FIG. 2B is a plan view.

FIG. 3 is a sectional view taken along line 3-3 of FIG.

FIG. 4 is an explanatory diagram showing a coolant circuit.

5 (a) is a plan view showing an embodiment of an apparatus preferably used for carrying out the present invention, and FIG. 5 (b) is a side view of the apparatus.

FIG. 6 is a side view showing the movable stand, the driving device, the fixed and movable clamps, the cutting device, and other members in FIGS.

7 (a) is an overall perspective view of the cutting device, FIG. 7 (b) is a sectional view taken along line 7-7 of FIG. 6, and FIG. 7 (c) is a plan view showing a part of the cutting device in section. It is a figure.

8A is a front view of the movable clamp, and FIG. 8B is a plan view of an upper clamper of the movable clamp.

FIG. 9 is a side view showing a cutting tip holding device for a tube material.

FIG. 10 is a side view showing a stretcher.

FIG. 11 is a side view showing a straightening roll device.

FIG. 12 is a plan view showing a layout of a tube transport device and a finishing press device.

FIG. 13 is a partial cross-sectional side view showing a finishing press device.

14A to 14C are explanatory views showing the outline of the finish cutting step.

15A to 15C are explanatory views showing the outline of the sizing step.

[Explanation of symbols]

 1 Flat tube 2 Fin 3 Header 4 Header 401 Uncoiler 402 Movable stand 404 Movable clamp 423 Cutting blade 406 Fixed clamp 407 Stretcher 408 Straightening device 429 Upper roller 430 Lower roller T Long flat tube C Press for finishing Machine

Claims (5)

(57) [Claims] 1. A plurality of fixed-length flat tubes stacked in the thickness direction with fins interposed therebetween, and a pair of hollow headers in which both ends of these flat tubes are connected for communication. Then, the heat exchange medium is a manufacturing method of a fixed-length flat tube used in a heat exchanger that is made to flow through a plurality of flat tubes at the same time, and a long flat tube material wound around an uncoiler, The movable clamp attached to the movable stand, which is placed in front of the uncoiler and reciprocates with a predetermined stroke,
A fixed-length drawing step of pulling out by a predetermined length corresponding to the stroke by being clamped in the forward movement process of the stand while being unclamped in the backward movement process of the stand, and a forward movement process of the stand And a cutting step of cutting a long flat tube material with a cutting blade provided on the stand and located in front of the clamp. 2. The fixed-length drawing step is arranged between the uncoiler and the stand, and a movable clamp attached to a movable stand that is arranged in front of the uncoiler and reciprocates with a predetermined stroke. By the fixed clamp, while the movable flat clamp holds the long flat tube material in the clamped state and the fixed clamp holds the unclamped state in the forward movement process of the stand, the fixed flat clamp holds the long flat tube material in the backward movement process of the movable stand. The method for producing a flat tube according to claim 1, wherein the fixed clamp is held in a clamped state and the movable clamp is held in an unclamped state. 3. A stretching step of applying a tension to a long flat tube material unwound from the uncoiler to perform work hardening by a stretcher arranged between the uncoiler and the fixed clamp, And a straightening step for straightening the bending of the stretched long flat tube material by a straightening device arranged between the stretcher and the fixed clamp. Method for manufacturing a flat tube of standard length. 4. The stretching step comprises: a plurality of upper rollers arranged at predetermined positions with a predetermined space between them; and a plurality of lower rollers vertically movably supported at a lower position between the upper rollers. Including the long flat tube material from the uncoiler is continuously passed in a meandering manner in each roller in a mode of circulating the lower roller, and the lower roller has its own weight during the intermittent drawing operation of the tube material. The method for producing a flat tube having a fixed length according to claim 3, wherein the flat tube is moved up and down. 5. A flattening step in which the cut tube material is further fed into a press for finishing, (a) the tube material is repeatedly bent into a wavy shape, and then straightened; (b) a tube. Finishing cutting step of cutting off both ends of the material to properly finish the dimension; (c) Sizing for performing swaging on both ends of the tube material to form an insertion end with a reduced cross-sectional area at the end. Step; (d) again, the same flattening step as the step (a) is performed, and each step of the final flattening step is sequentially performed to finish into a flat tube having a final predetermined size and shape. The method for manufacturing the flat-shaped flat tube according to claim 1 or 3.