JP2000326032A - Method for producing heat exchanger fin and die for heat exchanger fin - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily produce a through-hole with a collar having a prescribed height, even if a metal sheet harder and thinner than a conventional metal sheet is used. SOLUTION: When a heat exchanger fin is produced so that a cylindrical part is formed by burring a pierced hole by piercing at a container-shaped projecting part 18 formed, by drawing of one state or plural stages to reduce a shallow container shaped projecting part formed to a metal sheet 10 while substantially maintaining a thickness of the metal sheet 10 and has a prescribed height. Next by subjecting the cylindrical part to ironing, a through-hole with a collar having a prescribed height to insert a heat exchanger tube is formed, a pair of dies 30, 50 arranged to open/close is used for the dies for producing the heat exchanger fin, while a pair of the dies 30, 50 change from a die open state to a die closed state, piercing, burring and ironing are successively applied to the container-shaped projecting part 18.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a fin for a heat exchanger and a mold for a fin for a heat exchanger, and more particularly, to a heat exchanger for forming a through hole with a collar through which a heat exchange tube is inserted through a thin metal plate. The present invention relates to a method for manufacturing a fin for a container, and a die for a heat exchanger fin in which a cylindrical portion formed on a thin metal plate is ironed to form a through hole with a collar through which a tube for heat exchange is inserted.

[0002]

2. Description of the Related Art A fin for a heat exchanger used in a heat radiating portion of a heat exchanger such as a temperature controller has a plurality of through holes with collars of a predetermined height provided on a thin metal plate such as a rectangular aluminum plate. Is what is being done. The heat radiating portion of the heat exchanger formed by such heat exchanger fins is formed by stacking a plurality of heat exchanger fins in such a manner that the respective colored through holes are vertically aligned with each other, and these collared through holes are formed. A heat exchange tube made of a metal having a high thermal conductivity such as copper is inserted and integrated therewith. As a method for manufacturing such heat exchanger fins, the manufacturing method shown in FIGS. 9A and 9B is employed. In the manufacturing method of FIG. 9A, first, a piercing process is performed on the metal thin plate 100 to perform a burring process to form a cylindrical portion 101 whose peripheral edge is surrounded by the protruding pieces 102 [( a)], the protruding piece 102 is extended while forming the protruding piece 102 of the tubular portion 101 to form a collar 104 having a predetermined height [step (b) and (c)]. Then, color 10
The flange 105 is formed by bending the front end portion of [4] (step (d)) to obtain a through hole with a collar. Hereinafter, FIG.
The manufacturing method of (A) may be referred to as an ironing method.

[0005] The manufacturing method shown in FIG. 9B includes the following steps. First, a truncated cone-shaped shallow container-like convex portion 106 whose bottom diameter is larger than the opening diameter of the through hole with a collar formed in the metal thin plate 100 is formed (step (i)). The drawing process is performed to gradually increase the height while reducing the diameter of 106 (steps (ii), (iii), and (iv)). Furthermore,
Container-shaped convex portion 109 formed at a predetermined height by drawing
After the piercing process is performed to form a perforated hole, the perforated hole is burred to form the collar 104 [(v).
Process). Next, the front end of the collar 104 is bent to form a flange 105 (step (vi)), whereby a through hole with a collar can be obtained. Hereinafter, the manufacturing method of FIG. 9B may be referred to as a drawing method.

[0004]

The fins for heat exchangers according to the method for manufacturing fins for heat exchangers shown in FIG. 9 can be manufactured by press working. Of the methods for manufacturing the heat exchanger fins shown in FIG. 9, the ironing method of FIG. 9A has a shorter manufacturing process than the drawing method of FIG. The size of the heat exchanger fin mold used can be reduced. FIG. 9
The heat exchanger fin mold shown in FIG. 10 can be used as the heat exchanger fin mold used in the ironing method (A). FIG. 10 is a partial sectional view of a heat exchanger fin mold. The heat exchanger fin mold includes an upper mold 300 and a lower mold 400, and a die 116 is fixed by plates 112 and 114 constituting the upper mold 300. The die 116 is provided so that the tip thereof protrudes slightly downward from the surface of the plate 114 that forms the lower surface of the upper die 300.
The knockout 118 urged in the direction of is inserted with its outer peripheral surface slidably in contact with the inner wall surface of the die 116. As will be described later, the knockout 118 moves along with the punch 128 into which the punch 128 enters the die 116, performs ironing on the cylindrical portion 101, and then moves along with the retreating punch 128.
6 is an extruded member that pushes out the remaining collar 104 adhered to the inner wall surface.

[0005] Further, a member 132 inserted into a cylindrical member 126 fixed by plates 122 and 124 constituting the base of the lower die 300 causes the distal end portion to be a cylindrical member 126.
An ironing punch 128 is fixed to the lower die 300 so as to protrude from the lower die 300. The tip portion 13 of the punch 128 formed to have a diameter smaller than the diameter of the main body of the punch 128.
8 is a cylindrical portion 101 surrounded by a protruding piece 102.
The ironing process is performed by a corner 136 of the punch 128. In this way, lower mold 3
In the vicinity of the tip of the punch 128 fixed to the base of the sheet No. 00, a stripper plate 130 is provided at a predetermined distance from the base by being urged in the direction of the upper die 300 by an urging member (not shown). Have been. The stripper plate 130 has a through hole 13 through which a punch 128 can pass.
4, when the load is not applied to the stripper plate 130, the position of the stripper plate 130 is adjusted so that the tip of the punch 128 is below the upper surface of the stripper plate 130.

[0006] On the upper surface of the stripper plate 130, the cylindrical portion 1 whose periphery is surrounded by the protruding pieces 102.
01 on which the metal plate 100 is formed, and the cylindrical portion 101
Apply ironing. At this time, the upper die 300 moves downward, and the lower die pressing member (not shown) provided on the upper die 300 comes into contact with the stripper plate 130 and presses the stripper plate 130 downward. The distance from the base is reduced so that the tip of the punch 128 passes through the through hole 134 and projects onto the upper surface of the stripper plate 130. Further, by moving the upper die 300 downward, the tip of the punch 128 protruding from the upper surface of the stripper plate 130 enters the die 116 while pushing the knockout 118 upward against the urging force of the spring 120. Then, the cylindrical portion 101 is ironed with the inner wall surface of the die 116. Thereafter, the upper die 300 moves upward, and the tip of the punch 128 retreats from inside the die 116. At this time, the knockout 118 is lowered by the urging force of the spring 120 toward the lower die 400 while abutting on the retreating punch 128, and pushes out the collar 104 remaining on the inner wall surface of the die 116.

According to the ironing method shown in FIG. 9A using the heat exchanger fin mold shown in FIG. 10, a collar 104 standing upright to the thin metal plate 100 can be formed. For this reason, the adhesiveness with the heat exchange tube inserted into the finally obtained through hole with a collar can be improved.
However, the height of the collar 104 obtained by the ironing method of FIG. 9A is easily affected by the thickness of the metal sheet 100. For this reason, in the case where the weight of the heat exchanger is required as in recent years, the weight of the heat exchanger fin is reduced, and the heat exchanger fin is harder and thinner than the conventional one in order to maintain the strength and the like of the heat exchanger fin. It is necessary to use a thin metal plate.
As described above, when a through hole with a collar is formed using a thin metal plate that is harder and thinner than the conventional one by the ironing method of FIG. 9A, a collar having a predetermined height may be difficult to obtain. Further, in the heat exchanger fin mold shown in FIG. 10, it is extremely difficult to incorporate each of the punches 128 and the die 116 corresponding to each of the punches 128 into the mold so that the center axes thereof completely coincide with each other. Therefore, a deviation occurs between both central axes within the range of the installation accuracy. When such a shift between the two central axes occurs, when the punch 128 is inserted into the die 116, the distance between the inner wall surface of the die 116 and the outer wall surface of the punch 128 becomes uneven, which affects the projecting piece 102 of the cylindrical portion 101. The degree of ironing is different. For this reason, if the deviation between the central axes of the punch 128 and the die 116 becomes large, the thickness of the peripheral wall of the collar 104 becomes nonuniform as shown in FIG. May form an unbalanced collar formed at the inclined end inclined in the direction of the thick peripheral wall.

On the other hand, according to the drawing method shown in FIG. 9B, it is possible to form the container-like convex portion 109 having a predetermined height while substantially maintaining the thickness of the thin metal plate 100. For this reason, the collar 104 having a predetermined height can be formed even when a thin metal plate that is harder and thinner than the conventional one is used. However, the container-like convex portion 109
Is formed by reducing the diameter of the truncated conical convex portion 106 formed in the thin metal plate 100 and gradually increasing the height. For this reason, the cylindrical portion 104 formed by piercing and burring the container-like convex portion 109 has a vertical cross-sectional shape of “C”, and the finally formed through hole with a collar also has As shown in FIG. 12, the vertical cross-sectional shape is a "C" shape. As described above, when the heat exchange tube 110 is inserted into the collar-shaped through-hole having a vertical cross-sectional shape of “C”, a gap is easily formed between the inner wall surface of the collar and the outer wall surface of the heat exchange tube 110. And the adhesion between the two is reduced. Therefore, an object of the present invention is to provide a method of manufacturing a heat exchanger fin that can easily form a through hole with a collar having a predetermined height even when a thin metal plate that is harder and thinner than in the past is used, and a cylinder having a uniform height at the end. An object of the present invention is to provide a fin mold for a heat exchanger having a simple shape and a simple structure.

[0009]

In order to solve the above-mentioned problems, the present inventor has proposed that, in the drawing method shown in FIG. 9B, piercing and burring are performed on the container-like convex portion 109 formed by drawing. After forming the cylindrical portion 104 by performing the ironing process, when the cylindrical portion 104 is subjected to the ironing process, the piercing process, the burring process, and the ironing process are performed while the pair of molds are moved from the mold open state to the mold closed state. The die is placed on one side of the die so that the center axis of the die can be automatically adjusted when the cylindrical portion is automatically processed by the die and the punch. The present inventors arrived at the present invention as a result of considering that it is effective to play loosely on the surface. That is, the present invention provides a single-stage or multiple-stage drawing process for reducing the diameter of a shallow container-shaped projection formed on a thin metal plate, thereby achieving a predetermined height formed while substantially maintaining the thickness of the thin metal plate. A piercing process is performed on the container-shaped convex portion to form a pierced hole in the cylindrical portion by burring, and then the cylindrical portion is ironed to insert a heat exchange tube at a predetermined height. When manufacturing a heat exchanger fin formed by forming a through hole with a collar, a pair of molds provided to be openable and closable is used as a mold for manufacturing the heat exchanger fin, and the pair of molds is used. A fin for a heat exchanger, in which piercing, burring, and ironing are sequentially performed on the container-shaped convex portion at the same position of the mold during a period from when the mold is opened to when the mold is closed. Manufacturing method.

Further, the present invention provides a method for forming a container-like convex portion having a predetermined height by one or more stages of drawing to reduce the diameter of the shallow container-like convex portion formed on a thin metal plate. A piercing process is performed on the pierced portion to form a cylindrical portion by burring, and then the cylindrical portion is subjected to ironing to insert a heat exchange tube with a collar having a predetermined height. When manufacturing a heat exchanger fin having a through hole, a pair of molds provided to be openable and closable as one of the molds for manufacturing the heat exchanger fin. When the punch fixed to the other mold is inserted into the cylindrical portion inserted into the set die and ironing is performed with the die, the die moves in the same plane with respect to the punch. The distance between the inner wall surface of the die and the outer wall surface of the punch is A method for manufacturing a heat exchanger fin, comprising using a heat exchanger fin mold in which the die is loosely fitted to one of the molds so as to be adjusted uniformly over the entire circumference. .

Further, the present invention comprises a pair of molds provided to be openable and closable, in which a cylindrical portion formed in a thin metal plate is ironed to form a through hole with a collar for inserting a heat exchange tube. In the heat exchanger fin mold, a die attached to one of the molds and a punch fixed to the other mold and inserted into the die to perform ironing on the cylindrical portion of the thin metal plate. When the die and the punch are used to perform ironing on the cylindrical portion, the die moves in the same plane with respect to the punch, and the distance between the inner wall surface of the die and the outer wall surface of the punch is reduced by the die. The die for a heat exchanger fin, wherein the die is loosely fitted to one of the dies so as to be adjusted at a uniform interval over the entire circumference of the inner wall surface of the fin.

Further, the present invention provides a heat exchanger for ironing a cylindrical portion formed by piercing a container-shaped convex portion formed on a thin metal plate and burring a perforated hole. A heat exchanger fin mold comprising a pair of molds provided to be openable and closable, forming a through hole with a collar for inserting a tube, wherein one of the molds has a die and the other end has a tip. A piercing punch for performing piercing on the container-shaped convex portion, which is inserted and attached to the die so as to protrude in the direction of the mold, and the other mold includes the pair of molds. At the time of closing the mold, a hollow hole is formed in which the tip of a piercing punch that is mounted on one of the molds and pierced in the container-like projection is inserted, and the container is formed by the piercing. A burring hole for forming a perforated hole formed in the cylindrical convex portion in the cylindrical portion And a cylindrical punch for performing ironing on the cylindrical portion is fixed between the die into which the cylindrical portion is inserted, and ironing is performed on the cylindrical portion of the thin metal sheet by the die and the cylindrical punch. When applying, the die moves in the same plane with respect to the cylindrical punch, and the distance between the inner wall surface of the die and the outer wall surface of the cylindrical punch is adjusted to be uniform over the entire circumference of the inner wall surface of the die. As described above, the die for a heat exchanger fin is characterized in that the die is loosely fitted to one of the dies.

According to the method of manufacturing a fin for a heat exchanger according to the present invention, a piercing process and a burring process are performed on a container-like convex portion formed by drawing to form a cylindrical portion, and then an ironing process is performed on the cylindrical portion. When piercing, burring, and ironing are sequentially performed on the same part of the dies during a period from when the pair of dies is opened to when the pair of dies is closed. For this reason, the height of the collar obtained can be improved, and a through hole with a collar having a predetermined height can be formed even if a thinner metal plate that is harder and thinner than before is used. Furthermore, since the cylindrical portion is subjected to ironing, even if the vertical cross-sectional shape of the cylindrical portion is "C" -shaped, it can be corrected by applying ironing to the cylindrical portion, and the color finally obtained is obtained. Can be erected at right angles on a thin metal plate. In addition, since the piercing, burring, and ironing are performed at the same location on the mold, the heat exchanger fin mold has substantially the same size as the heat exchanger fin mold used in the conventional drawing method. In addition, since it is not necessary to move the metal sheet to each processing step of the metal mold, it is possible to prevent the occurrence of misalignment of the cylindrical portion formed on the thin metal sheet as much as possible. This can prevent the occurrence of unbalanced color.

Further, in the heat exchanger fin mold according to the present invention, the fin is fixed to a cylindrical portion formed on a thin metal plate inserted into a die mounted on one of the dies and to the other mold. When the punch is inserted and ironing is performed, the die moves in the same plane with respect to the punch so that the distance between the inner wall surface of the die and the outer wall surface of the punch is uniform over the entire circumference of the inner wall surface of the die. The die is loosely fitted to one of the molds to be adjusted. For this reason, even if the center of the die and the punch mounted on the die are displaced from each other, the die moves in the same plane with respect to the punch during ironing, and The interval between the wall surface and the outer wall surface of the punch can be automatically adjusted to be as uniform as possible, and the degree of ironing on the cylindrical portion formed on the metal sheet can be made as uniform as possible. As a result, a collar having the same height at the tip can be obtained.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, as shown in FIG. 1, first, a shallow container-like convex portion 12 is formed on a thin metal plate 10 [step of FIG. 1 (a)]. The shallow container-like convex portion 12 is subjected to drawing at a plurality of stages (three stages in FIG. 1), so that the diameter of the shallow container-like convex portion 12 is gradually reduced, and the container-like convex portion 18 having a predetermined height is formed.
[FIGS. 1 (b), (c) and (d)]. Since the container-like protrusion 18 is formed by reducing the diameter of the shallow container-like protrusion 12, the thickness of the wall of the container-like protrusion 18 is substantially the same as that of the metal sheet 10. Is the thickness. Next, a perforation hole formed by piercing on the upper surface of the container-like convex portion 18 is formed in the cylindrical portion 20 by burring [FIG.
(E)]. The wall of the cylindrical portion 20 has substantially the same thickness as the thin metal plate 10. After that, the cylindrical portion 20 is ironed to form the collar 22, and then the distal end portion of the collar 22 is bent to form the collar 24, thereby forming the collared through-hole 26. A pair of dies that can be opened and closed and that form such a through hole 26 with a collar are provided with a die or a punch corresponding to each of the steps of FIGS. Etc. are sequentially mounted.

However, the number of steps in the step shown in FIG. 1 is larger than that in the drawing method shown in FIG. In this regard, in the present invention, the steps of piercing and burring [FIG.
(E)] and the step of ironing (FIG. 1 (f)) are performed at the same location of the mold, thereby preventing the mold for the heat exchanger fin from being enlarged as much as possible. FIG. 2 shows a heat exchanger fin mold in which piercing, burring, and ironing can be performed at the same location. FIG. 2 is a partial cross-sectional view of a heat exchanger fin mold for manufacturing a heat exchanger fin by the manufacturing process shown in FIG.
After forming a perforated hole formed by performing piercing on the container-shaped convex portion 18 having a predetermined height formed by drawing on the metal thin plate 10, the cylindrical portion 20 is formed by burring.
This is a portion where the collar 22 is formed by ironing the cylindrical portion 20.

This heat exchanger fin mold comprises an upper mold 30 and a lower mold 50 which are provided to be openable and closable.
The die 34 and the piercing punch 36 are mounted by the plates 31, 32, and 33 constituting the “0”. The piercing punch 36 is inserted into the die 34 so that its tip projects in the direction of the lower mold 50, and is fixed by the plates 31 and 32. The die 34 is mounted so that its tip protrudes slightly downward from the surface of the plate 33 forming the lower surface of the upper die 30, and as shown in FIG.
The gaps 38 and 39 are formed on the side and top sides of the die 34 and are loosely fitted in the storage chamber 35 formed between the dies 34. Therefore, the die 34 can move in the same plane. The moving width of the die 34 is the width of the gap 38 with respect to the piercing punch 36. Further, the cylindrical punch 5 is formed by plates 51, 52 and 53 constituting the base of the lower die 50.
4 is fixed. This cylindrical punch 54 has an upper die 3
When the mold 0 and the lower mold 50 are closed, the tip of the piercing punch 36 fixed to the upper mold 30 is inserted, and a hollow hole 55 is formed through which drilling dust generated during piercing passes. Have been. The distal end portion 56 of the cylindrical punch 54 is formed to have a smaller diameter than the outer diameter of the main body portion 57 of the cylindrical punch 54, and serves as a guide portion to a perforated hole formed by the piercing punch 34. The inclined portion 58 formed on the inclined surface between the distal end portion 56 and the main body portion 57 is a portion for performing burring processing on a drilled hole formed by piercing.
The portion where the cylindrical portion 20 formed by the burring process is subjected to the ironing process is a corner portion 59 between the inclined portion 57 and the main body 56.
It is.

A spring 60 as an urging member is urged in the direction of the upper mold 30 in the vicinity of the distal end portion 56 of the cylindrical punch 54 fixed to the base of the lower mold 50, and a predetermined distance is formed between the lower die 50 and the base. A stripper plate 62 is provided at a distance. The stripper plate 62 is provided with a through hole 64 through which the main body 57 of the cylindrical punch 54 can pass. When no load is applied to the stripper plate 64, the tip of the cylindrical punch 54 is attached to the stripper plate 64. The position of the stripper plate 64 is adjusted so as to be lower than the upper surface of the stripper plate. In the mold shown in FIG.
1A to 1D have the same structure as the mold used in the conventional drawing method.

The upper mold 3 for the heat exchanger fin mold shown in FIG.
The metal sheet 10 on which the container-shaped convex portion 18 is formed is fed between 0 and the lower mold 50, and the closing of the upper mold 30 and the lower mold 50 is started. At this time, when the upper mold 30 starts to descend, the lower mold pressing member (not shown) provided on the upper mold 30 comes into contact with the stripper plate 62 and resists the urging force of the spring 60. Is pressed downward, and as shown in FIG. 4, the cylindrical punch 5 passing through the through hole 64 of the lower mold 50 is pressed.
A zero-end portion 56 projects from the upper surface of the stripper plate 62. The distal end portion 56 of the cylindrical punch 50 projecting from the upper surface of the stripper plate 62 is inserted into the container-like projection 18 formed on the thin metal plate 10 as shown in FIG. I do. Furthermore, the hollow hole 55 of the distal end portion 56 of the cylindrical punch 54 protruding from the upper surface of the stripper plate 64 pushed down by descending the upper die 30 and inserted into the container-like convex portion 18 of the thin metal plate 10, The tip of a piercing punch 36 fixed to the upper die 30 is inserted, and piercing is performed on the upper surface of the container-like projection 18 to form a piercing hole. The opening area of the perforation hole is smaller than the area of the upper surface of the container-like projection 18. The drilling waste generated by the piercing is discharged out of the mold through the hollow hole 55 of the cylindrical punch 54.

The lowering of the upper mold 30 is continued, and the cylindrical punch 54
The tip portion 56 of the cylindrical portion 54 further projects from the upper surface of the stripper plate 64, so that the piercing hole formed in the upper surface of the container-like convex portion 18 is subjected to burring by the inclined portion 59 of the cylindrical punch 54 so as to form the cylindrical portion. 20 is formed. By continuing the lowering of the upper die 30, the cylindrical portion 2 inserted into the die 34 mounted on the upper die 30 as shown in FIG.
0 is ironed with the die 34 and the corners 59 of the cylindrical punch 54. During such ironing, the die 34
It is important that the center axes of the and the cylindrical punch 54 completely coincide with each other in order to obtain the collar 22 having the tip formed at the same height. However, it is very difficult to incorporate the die 34 and the cylindrical punch 54 into the mold so that the central axes of the two coincide completely.

In this regard, as shown in FIG. 3, the die 34 is loosely fitted in the storage chamber 35 formed in the upper die 30 with gaps 38 and 39 formed. For this reason, at the time of ironing, the tie 34 is attached to the cylindrical punch 54 fixed to the lower die 50.
Can move in the same plane, and the distance between the inner wall surface of the die 34 and the outer wall surface of the cylindrical punch 54 can be adjusted to be uniform over the entire circumference of the inner wall surface of the die 34. That is, when the center axes of the die 34 and the cylindrical punch 54 mounted on the mold are shifted, the distance between the inner wall surface of the die 34 and the outer wall surface of the cylindrical punch 54 becomes uneven. Therefore, when the cylindrical portion 20 is ironed by the die 34 and the cylindrical punch 54, the force applied to the die 34, particularly, the force applied in the direction perpendicular to the center axis of the die 34 is The distance between the inner wall surface of the die 34 and the outer wall surface of the cylindrical punch 54 is deflected from the narrow gap to the wide gap. The die 34 to which the deflected force is applied is loosely fitted in the storage chamber 35 of the upper die 30 with gaps 38 and 39 formed therein, and therefore moves in the direction in which the force is applied. When this movement is completed, as shown in FIG. 6, the center axes of the die 34 and the cylindrical punch 54 coincide with each other, and the distance between the inner wall surface of the die 34 and the outer wall surface of the cylindrical punch 54 is It is adjusted at uniform intervals over the entire circumference of the inner wall surface. As a result, the cylindrical portion 20
, A uniform ironing process is applied over the entire circumference, and a collar 22 having the same height at the tip can be obtained.

The ironing is performed by the upper die 30 and the lower die 50.
When the mold closing is completed, the mold opening of the upper mold 30 and the lower mold 50 is started. When the upper die 30 moves upward and the tip of the cylindrical punch 54 retreats from the die 34, the formed collar 22 is extracted from the die 34. In the method for manufacturing the heat exchanger fins illustrated in FIG. 1, the ironing rate in the ironing performed on the cylindrical portion 20 is lower than that in the case where the heat exchanger fins are manufactured by the ironing method illustrated in FIG. 9A. Therefore, the collar 22 can be easily pulled out of the die 34 by a pressing force on the thin metal plate 10 by an ejector pin (not shown) normally provided near the die 34 and the cylindrical punch 54 shown in FIG. ,
It is not necessary to particularly provide knockout 118 shown in FIG. When the mold opening of the upper mold 30 and the lower mold 50 is completed, the metal sheet 10 on the stripper plate 62 is sent to the next step.

The heat exchanger fin molds shown in FIGS. 2 to 6 are processed by piercing and burring processes (FIG. 1).
(E)] and the ironing process (FIG. 1 (f)) are performed at the same location of the die, but the piercing, burring, and ironing processes are performed at different locations on the die. May be applied. Also in this case, in order to prevent the cylindrical portion 20 from being ironed in a state where the center axes of the die and the punch are displaced, and to perform the uniform and uniform ironing on the cylindrical portion 20 as shown in FIG. A heat exchanger fin mold is used. FIG.
FIG. 7 is a partial cross-sectional view of a portion where the cylindrical portion 20 formed on the thin metal plate 20 is subjected to ironing. The same members as those of the heat exchanger fin mold shown in FIGS. Detailed description is omitted. In the heat exchanger fin mold shown in FIG.
Only the die 34 is loosely fitted in the storage chamber 35 provided in the upper die 30 with gaps 38 and 39 (FIG. 3) formed on the side and top sides of the die 34. Further, a solid punch 66 for ironing the cylindrical portion 20 inserted into the die 34 mounted on the upper die 30 is fixed to the lower die 50 when the die is closed.

According to the heat exchanger fin mold shown in FIG. 7, when the upper mold 30 and the lower mold 50 are closed, the upper mold 30 is closed.
Is started, the lower die pressing member (not shown) provided on the upper die 30 contacts the stripper plate 62 and resists the urging force of the spring 60.
2 is pressed downward, and the tip end portion 56 of the punch 66 that has passed through the through hole 64 of the lower die 50 projects onto the upper surface of the stripper plate 62. The tip of the punch 66 protruding from the upper surface of the stripper plate 62 is inserted into the cylindrical portion 20 of the thin metal plate 10. Further, by lowering the upper mold 30, the tip of the punch 66 further protrudes from the upper surface of the stripper plate 64, so that the cylindrical part 20 inserted into the die 34 mounted on the upper mold 30 Ironing is performed with the punch 66. In the heat exchanger fin mold of FIG. 7, the die 34 is loosely fitted in the storage chamber 35 formed in the upper mold 30 with gaps 38 and 39 formed. For this reason, even when the two central axes of the die 34 and the punch 66 are shifted from each other, the die 34 is fixed to the lower die 50 when the ironing process is performed.
, The distance between the inner wall surface of the die 34 and the outer wall surface of the punch 66 can be automatically adjusted to a uniform distance over the entire circumference of the inner wall surface of the die 34. As a result, the cylindrical portion 20
Can be applied uniformly over the entire circumference, and it is possible to obtain the collar 22 having the same height at the tip.

The heat exchanger fin mold described above is a mold used in the method for manufacturing the heat exchanger fin shown in FIG. 1, but the heat exchanger fin mold according to the present invention is not shown in FIG. It can be applied to the ironing method shown in FIG. FIG. 8 shows a heat exchanger fin mold applicable to this ironing method.
Shown in FIG. 8 is a partial cross-sectional view of a portion where the protruding piece 72 of the cylindrical portion 70 formed by performing piercing and burring on the metal thin plate 20 is subjected to ironing, and the heat exchanger fins illustrated in FIGS. The same members as those of the metal mold are given the same numbers, and the detailed description is omitted. In the heat exchanger fin mold shown in FIG. 8, the die 34 is provided in the storage chamber 35 provided in the upper die 30 with gaps 38, 3 on the side and top sides of the die 34.
9 (FIG. 3) are loosely fitted. Further, a knockout 68 is provided in the die 34 so as to be able to move up and down in sliding contact with the inner wall surface of the die 34, and the knockout 68 serves as an urging member provided on the plate 32 of the upper die 30. The spring 74 is urged in the direction of the lower mold 50 so that the tip protrudes from the tip surface of the die 34. A gap is formed between the inner wall surface of the passage 76 of the plate 32 into which the knockout 68 is inserted and the outer peripheral surface of the knockout 68 so that the knockout 68 can move together with the die 34. A solid punch 66 for ironing the projecting piece 72 of the cylindrical portion 70 inserted into the die 34 mounted on the upper mold 30 when the mold is closed is fixed to the lower mold 50. I have.

According to the heat exchanger fin mold shown in FIG. 8, when the upper mold 30 and the lower mold 50 are closed, the upper mold 30 is closed.
Is started, the lower die pressing member (not shown) provided on the upper die 30 contacts the stripper plate 62 and resists the urging force of the spring 60.
2 is pressed downward, and the tip end portion 56 of the punch 66 that has passed through the through hole 64 of the lower die 50 projects onto the upper surface of the stripper plate 62. The tip of the punch 66 projecting from the upper surface of the stripper plate 62 is inserted into the cylindrical portion 70 of the thin metal plate 10. Further, by lowering the upper mold 30 to further project the tip of the punch 66 from the upper surface of the stripper plate 64, the knockout 68 is pushed up against the urging force of the spring 74 toward the lower mold 50, The projecting piece 72 of the cylindrical portion 70 inserted into the die 34 mounted on the upper die 30 is subjected to ironing by the die 34 and the punch 66. In the heat exchanger fin mold of FIG.
The die 34 has a gap 3 in a storage chamber 35 formed in the upper die 30.
8 and 39, the outer peripheral surface of the knockout 68 which moves up and down by slidingly contacting the inner wall surface of the die 34 and the passage 7
A gap is also formed between the inner wall surface and the inner wall surface. For this reason, even when the center axes of the die 34 and the punch 66 are shifted from each other and are mounted on the mold, the projecting piece 7
The die 34 is knocked out 6
8 and the punch 66 fixed to the lower die 50 in the same plane.
Can be automatically adjusted to a uniform interval over the entire circumference of the inner wall surface of the die 34. As a result, uniform ironing can be performed over the entire circumference of the cylindrical portion 20, and a color with the same height at the tip can be obtained.

[0027]

According to the present invention, even if a harder and thinner metal sheet is used than before, a uniform colored through hole with a predetermined height can be formed perpendicularly to the metal sheet, and it can be inserted through the collar with a through hole. As a result, the heat conductivity with the heat exchange tube can be improved, so that the weight of the heat exchanger can be reduced and the thermal efficiency can be improved.

[Brief description of the drawings]

FIG. 1 is a process diagram illustrating an example of a method for manufacturing a heat exchanger fin according to the present invention.

FIG. 2 is a partial cross section illustrating an example of a heat exchanger fin mold according to the present invention.

3 is an enlarged partial sectional view of the heat exchanger fin mold shown in FIG. 2;

FIG. 4 is a partial cross-sectional view illustrating a state immediately after the mold for a heat exchanger fin shown in FIG. 2 starts to close the mold.

FIG. 5 is a partial cross-sectional view illustrating a closed state of the heat exchanger fin mold shown in FIG. 2;

FIG. 6 is an enlarged partial cross-sectional view of the heat exchanger fin mold shown in FIG. 2 in a mold closed state.

FIG. 7 is a partial cross-sectional view illustrating another example of the heat exchanger fin mold according to the present invention.

FIG. 8 is a partial cross-sectional view illustrating another example of the heat exchanger fin mold according to the present invention.

FIG. 9 is a process diagram illustrating a conventional method for manufacturing a heat exchanger fin.

FIG. 10 is a partial sectional view illustrating a conventional heat exchanger fin mold.

FIG. 11 is a longitudinal sectional view of a collar that may be formed by a conventional heat exchanger fin mold.

FIG. 12 is a longitudinal sectional view of a through hole with a collar which may be formed by a conventional method for manufacturing a heat exchanger fin.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Metal thin plate 12 Shallow container-shaped convex part 18 Container-shaped convex part 20, 70 Cylindrical part 22 Collar 24 Flange 26 Colored through-hole 30 Upper die 31, 32, 33, 51, 52, 53 Plate 34 Die 35 Storage chamber 36 Pierce punches 38, 39 Gap 50 Lower die 54 Cylindrical punch 55 Hollow hole 60, 74 Spring as biasing member 62 Stripper plate 66 Punch 68 Knockout 72 Projection piece of cylindrical portion 70 Passage through which knockout 68 is inserted

Claims (5)

[Claims] 1. A container having a predetermined height formed by substantially reducing the diameter of a shallow container-like projection formed on a thin metal plate by one or more stages of drawing to substantially maintain the thickness of the thin metal plate. A pierced hole is formed in the cylindrical convex portion by piercing to form a cylindrical hole in the cylindrical portion, and then the cylindrical portion is ironed to a predetermined height through which a heat exchange tube is inserted. When manufacturing a heat exchanger fin formed with a through hole with a collar, a pair of molds provided to be openable and closable, as a mold for manufacturing the heat exchanger fins, the pair of molds Between the mold open state and the mold closed state, at the same place of the mold, piercing processing, burring processing, and ironing processing are sequentially performed on the container-shaped convex portion. Production method. 2. A piercing process for forming a perforated hole in a container-shaped convex portion formed in a thin metal plate, a burring process for forming the perforated hole in a cylindrical portion, and an ironing process for the cylindrical portion are performed. As a pair of molds provided to be openable and closable, one of the molds was mounted by being inserted into the die such that a tip thereof protrudes in the direction of the other mold,
A piercing punch for piercing the container-shaped protrusion, wherein the other mold is mounted on one of the dies when the pair of dies is closed, and the container-shaped protrusion is provided. A burring process in which a hollow hole into which the tip of a piercing punch subjected to piercing is inserted is formed, and a piercing hole formed in the container-like projection by the piercing is formed in a cylindrical portion, A die to which a cylindrical punch for performing ironing on the cylindrical portion is fixed between a die in which the cylindrical portion is inserted, and a die formed by thinning a metal plate with the die and the cylindrical punch. When ironing is performed, the die moves in the same plane with respect to the cylindrical punch, and the distance between the inner wall surface of the die and the outer wall surface of the cylindrical punch is uniform over the entire circumference of the inner wall surface of the die. Heat exchange where the die is loosely fitted to one of the molds so as to adjust the spacing The method for producing a fin for a heat exchanger according to claim 1, wherein a mold for an exchanger fin is used. 3. A container-like projection having a predetermined height is formed by one or more stages of drawing to reduce the diameter of the shallow container-like projection formed on the thin metal plate, and then the container-like projection is pierced. The pierced hole formed by burring is formed to form a cylindrical portion, and then the cylindrical portion is ironed to form a through hole with a collar having a predetermined height through which a heat exchange tube is inserted. When manufacturing the heat exchanger fins, a pair of molds provided to be openable and closable as dies for manufacturing the heat exchanger fins, and a die mounted on one of the dies. When inserting a punch fixed to the other mold into the inserted cylindrical portion and performing ironing with the die, the die moves in the same plane with respect to the cylindrical punch. The distance between the inner wall surface of the die and the outer wall surface of the punch extends around the entire inner wall surface of the die. A method for manufacturing a fin for a heat exchanger, wherein the die is loosely fitted to one of the dies so as to be adjusted at a uniform interval. 4. A heat exchanger fin comprising a pair of molds openably and closably formed by ironing a cylindrical portion formed on a thin metal plate to form a through hole with a collar for inserting a heat exchange tube. A metal mold, comprising: a die mounted on one of the metal molds; and a punch fixed to the other metal mold and inserted into the die to perform ironing on the cylindrical portion of the thin metal plate; and When ironing is performed on the cylindrical portion by the die and the punch, the die moves in the same plane with respect to the punch, and the distance between the inner wall surface of the die and the outer wall surface of the punch is smaller than the inner wall surface of the die. The die for a heat exchanger fin, wherein the die is loosely fitted to one of the dies so as to be adjusted at a uniform interval over the entire circumference. 5. A cylindrical portion formed by piercing a container-shaped convex portion formed in a thin metal plate and piercing a pierced hole, and ironing the cylindrical portion formed by burring to insert a heat exchange tube. A heat exchanger fin mold comprising a pair of molds provided to be openable and closable, forming a through hole with a collar, wherein one of the molds has a die and a tip part of the other mold. A piercing punch for piercing the container-shaped convex portion, which is inserted and attached to the die so as to protrude in the direction, and the other mold has a closed mold of the pair of molds. At this time, a hollow hole is formed in which the tip of a piercing punch that is attached to one of the molds and is pierced in the container-shaped protrusion is inserted, and the container-shaped protrusion is formed by the piercing. A burring process for forming a drilled hole in a cylindrical portion; A cylindrical punch for performing ironing on the cylindrical portion is fixed between the die and the inserted die, and when the cylindrical portion of the metal sheet is ironed by the die and the cylindrical punch, the die is used. Is moved in the same plane with respect to the cylindrical punch, so that the interval between the inner wall surface of the die and the outer wall surface of the cylindrical punch is adjusted at a uniform interval over the entire circumference of the inner wall surface of the die. A die for a heat exchanger fin, wherein the die is loosely fitted to one of the dies.