JP3410883B2 - Heat exchanger manufacturing method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat transfer tube having a plurality of heat dissipating fins and a heat transfer tube inserted into the heat dissipating fin, the heat dissipating fins being polymerized to form a heat exchanger used in an air conditioner, a cooler, or the like. TECHNICAL FIELD The present invention relates to a method for manufacturing a heat exchanger for integrally integrating by action.

[0002]

When a heat exchanger is conventionally manufactured, as shown in FIG. 5 (a), a primary pipe expanding mandrel 4 having a pipe expanding billet 4a attached to its tip is polymerized. The heat transfer tube 3 is inserted through the plurality of heat dissipation fins 2 and is press-fitted from the tube opening 3b of the protruding portion 3a of the heat transfer tube 3 which has a predetermined size and protrudes from the heat dissipation fins 2 and the end plate 8 on the one end side so that the heat transfer tube 3 By expanding the pipes, the heat transfer pipes 3 and the radiating fins 2 are integrally combined. However, before expanding the pipes, a predetermined number of heat transfer pipes 3 are preliminarily provided in a plurality of holes formed in the radiating fins 2 in a predetermined pattern. The heat exchanger 1 is inserted and formed to form the heat exchanger 1 before pipe expansion.

Therefore, the outer diameter of the heat transfer tube 3 inserted into the heat dissipation fin 2 is naturally smaller than the inner diameter of the hole formed in the heat dissipation fin, and therefore the heat transfer tube 3 and the heat dissipation are used. The fin 2 is usually not in a sufficiently close contact state. Therefore, as shown in FIG. 6B, the primary pipe expanding mandrel 4 is press-fitted (arrow E) from the pipe port 3b of the protruding portion 3a of the heat transfer pipe 3 to expand the heat transfer pipe 3, and the heat transfer pipe 3 is expanded. The heat radiating fins 2 are brought into close contact with the outer peripheral portion of the heat transfer tube 3. However, due to the material sink associated with the expansion of the heat transfer tube 3, the heat transfer tube 3 not only shrinks in the tube expanding direction of the primary tube expanding mandrel 4 (arrow D) but also , A strain is generated to slightly incline in the direction intersecting with the pipe expanding direction, and the axis of the heat transfer tube (arrow A) does not coincide with the axis of the primary expanding mandrel 4 (arrow B). ) May be included. It should be noted that the tube openings 3b of the heat transfer tubes 3 that have been subjected to the primary expansion as described above are generally U-shaped connecting tubes (not shown) for connecting the expanded heat transfer tubes 3 in a predetermined pattern. It is general to perform secondary flare or secondary and tertiary flare processing for inserting and brazing.

Therefore, as shown in FIG. 3C, in order to insert a substantially U-shaped connecting pipe (not shown) into the pipe opening 3b of the heat transfer pipe 3 which has completed the primary expansion, for example, It is slidably fitted on the primary pipe expanding mandrel 4 to perform secondary and tertiary flare processing, and has the same axial center as that of the primary pipe expanding mandrel 4 and the secondary flare punch portion 5a and tertiary. When the flare punch 5 having the flare punch portion 5b is press-fitted into the tube opening 3b of the heat transfer tube 3, not only is the overall length reduced in the tube expanding direction of the primary tube expanding mandrel 4 as described above,
Since the axial center of the tube opening 3b of the heat transfer tube 3 which is distorted so as to be slightly inclined in the direction intersecting the expansion direction does not coincide with the axial center of the flare punch 5, the flare punch 5 moving forward is In some cases, the galling deformed portion 9 may be formed in the pipe mouth 3b by chewing the peripheral portion of the pipe opening 3b of the heat transfer tube 3 that has undergone the primary expansion. Therefore, the galling deformed portion 9 has the substantially U-shape. There was a very serious problem that it would cause liquid leakage after brazing a connecting pipe (not shown) to the pipe opening 3b after flaring.

The present invention solves the above problems,
At the mouth of the heat transfer tube with the primary expansion, a predetermined flare punch is provided at the mouth of the heat transfer tube to perform secondary flare or second or third flare processing for inserting the approximately U-shaped connecting tube. In the case of press-fitting, even if the heat transfer tube shrinks in its entire length in the expansion direction of the primary expansion mandrel and is distorted to slightly incline in the direction intersecting the expansion direction, the tube of the heat transfer tube An object of the present invention is to provide an extremely excellent method for manufacturing a heat exchanger, which can surely perform a predetermined flare process on a tube opening of a heat transfer tube without biting the peripheral portion of the opening.

[0006]

The present invention invents a completely new method for manufacturing a heat exchanger in order to solve the above problems,
The following measures have been taken.

That is, according to the present invention, the heat transfer tube 3 is inserted through the plurality of heat radiation fins 2 which are overlapped with each other, and then the heat transfer tube 3 is projected from the heat radiation tube 3 having a predetermined size from the heat radiation tube 3 on one end side. The mandrel 4 for secondary pipe expansion was press-fitted, and then 1
When the pipe expanding action portion at the tip of the secondary pipe expanding mandrel is located in the vicinity of the heat radiating fins on the one end side, at least the flare punch 5 capable of secondary pipe expansion is press-fitted into the pipe opening 3b from the pipe opening 3b with a predetermined size. When the flare portion 6 of the primary pipe expanding mandrel 4 is stopped, the primary pipe expanding mandrel 4 is press-fitted into the heat transfer pipe 3, and the pipe expanding action portion of the primary pipe expanding mandrel 4 is expanded deepest in the heat transfer pipe 3. Until it reaches
Since the flare punch 5 is press-fitted into the heat transfer tube 3, it is possible to form a slight flare portion 6 at the opening 3b of the heat transfer tube 3 in the initial stage of the primary expansion.
The heat transfer tube 3 has a slight misalignment in the middle of the next tube expansion, and the tube mouth 3b
Even if the tip of the flare punch 5 is inclined to approach the peripheral surface of the primary expanding mandrel 4, the tip of the flare punch 5 can be slightly flared without biting the mouth 3b of the heat transfer tube 3 with the tip of the flare punch 5. The desired flare processing 7 can be applied to the heat transfer tube 3 at the time of primary expansion.

Further, according to the present invention, the heat transfer tube 3 is inserted through the plurality of heat radiation fins 2 which are overlapped with each other, and the heat transfer tube 3 is projected from the heat radiation tube 3 having a predetermined size from the heat radiation fin on the one end side. The mandrel 4 for secondary pipe expansion was press-fitted, and then 1
When the pipe expanding action portion at the tip of the secondary pipe expanding mandrel is located in the vicinity of the heat radiating fins on the one end side, at least the flare punch 5 capable of secondary pipe expansion is press-fitted into the pipe opening 3b from the pipe opening 3b with a predetermined size. When the flare portion 6 of the primary pipe expanding mandrel 4 is stopped, the primary pipe expanding mandrel 4 is press-fitted into the heat transfer pipe 3, and the pipe expanding action portion of the primary pipe expanding mandrel 4 is expanded deepest in the heat transfer pipe 3. Since the flare punch 5 is press-fitted into the heat transfer tube 3 after reaching the heat transfer tube 3, it becomes possible to form a slight flare portion 6 at the tube opening 3b of the heat transfer tube 3 in the initial stage of the primary expansion. Even when the heat transfer tube 3 has a large misalignment at the end of the tube expansion and the tube opening 3b is in contact with the peripheral surface of the primary tube expanding mandrel 4 and inclined, the tube opening 3b of the heat transfer tube 3 is The flare punch 5 does not bite at the tip of the flare punch. A desired flare processing 7 can be applied to the heat transfer tube 3 after the completion of the primary expansion by allowing the tip of the rare punch 5 to enter a slight flare portion 6.

Further, according to the present invention, the heat transfer tube 3 is inserted through the plurality of heat radiation fins 2 which are overlapped with each other, and then the heat transfer tube 3 protrudes from the heat radiation fin 2 on one end side with a predetermined size from the tube opening 3b. At the time of press-fitting the primary pipe expanding mandrel 4 and pressurizing at least the secondary pipe flaring punch 5 from the pipe port 3b to a predetermined size, and forming a slight flare portion 6 at the pipe port 3b.
The flare punch 5 to the heat transfer tube 3 until the tube expanding action part of the primary tube expanding mandrel 4 press-fitted into the heat transfer tube 3 reaches the deepest tube expansion part of the heat transfer tube 3. Since it is press-fitted, it becomes possible to form a slight flare portion 6 in the tube opening 3b of the heat transfer tube 3 during the primary expansion, and thus the heat transfer tube 3 has a slight misalignment during the primary expansion. Even when the pipe mouth 3b is inclined to approach the peripheral surface of the primary expansion mandrel 4, the tip of the flare punch 5 is slightly scratched without biting the pipe mouth 3b of the heat transfer tube 3 with the tip of the flare punch 5. The desired flare processing 7 can be applied to the flare portion 6 and applied to the heat transfer tube 3 during the primary expansion.

Further, according to the present invention, the heat transfer tube 3 is inserted into the plurality of heat radiation fins 2 which are overlapped with each other, and then the heat transfer tube 3 protrudes from the heat radiation fin 2 on one end side with a predetermined size from the tube opening 3b. At the time of press-fitting the primary pipe expanding mandrel 4 and pressurizing at least the secondary pipe flaring punch 5 from the pipe port 3b to a predetermined size, and forming a slight flare portion 6 at the pipe port 3b.
In stops, then after the tube expansion working portion of the primary tube expanding mandrel 4 to be pressed into the heat transfer tube 3 has reached the expanded pipe deepest portion of the heat transfer tubes 3, press-fitting the flare punch 5 to the heat transfer tubes 3 Since the heat transfer tube 3 is subjected to the primary tube expansion and flare processing, it becomes possible to form a slight flare portion 6 at the tube opening 3b of the heat transfer tube 3 during the primary tube expansion, and thus the heat transfer tube at the end of the primary tube expansion. Even when 3 has a large misalignment and the pipe mouth 3b is in contact with the peripheral surface of the primary expanding mandrel 4 and is inclined, the pipe mouth 3b of the heat transfer pipe 3 is formed at the tip of the flare punch 5. The desired flare processing 7 can be applied to the heat transfer tube 3 after the completion of the primary tube expansion by allowing the tip of the flare punch 5 to slightly enter the flare portion 6 without biting.

Further, according to the present invention, the heat transfer tube 3 is inserted through the plurality of heat radiating fins 2 which are overlapped with each other, and the heat transfer tube 3 is projected from the heat radiating fin 3 on one end side with a predetermined size from the tube opening 3b.
While press-fitting the secondary pipe expanding mandrel 4, at least a secondary pipe flaring punch 5 is inserted or pressed into the pipe port 3b to a predetermined size to form a slight flare portion 6 in the pipe port 3b.
After that, the flare punch 5 is transmitted while maintaining the state in which the flare punch 5 is brought into contact with the tube opening 3b of the heat transfer tube 3 whose overall length is reduced through expansion by the primary tube expanding mandrel 4 which is press-fitted into the heat transfer tube 3. The flare punch 5 is pressed into the heat transfer tube 3 until it moves in synchronization with the shrinkage of the heat tube 3 and then the tube expansion action part of the primary tube expansion mandrel 4 reaches the deepest tube expansion part of the heat transfer tube 3. Therefore, even during the primary expansion, the tip of the flare punch 5 is always inserted or pressed into the tube opening 3b of the heat transfer tube 3 and abutted without a gap, so that the heat transfer tube 3 is misaligned. The desired flare processing 7 can be applied to the heat transfer tube 3 during the primary expansion without performing the above.

Further, according to the present invention, the heat transfer tube 3 is inserted through the plurality of heat radiating fins 2 which are overlapped with each other, and then the heat transfer tube 3 is projected from the heat radiating fins at one end side with a predetermined size from the tube opening 3b. While press-fitting the secondary pipe expanding mandrel 4, at least a flare punch 5 capable of secondary pipe expansion is inserted or pressed into the pipe opening 3b to a predetermined size to form a slight flare portion 6 in the pipe opening 3b.
And, then the heat transfer tube ductal orifice of the heat transfer tubes 3 that the total length shrinks through the tube expansion by the primary tube expanding mandrel 4 to be pressed into the 3
While maintaining the flare punch 5 in contact with 3b, the flare punch 5 is moved in synchronism with the shrinkage of the heat transfer tube 3, and then the tube expanding action portion of the primary tube expanding mandrel 4 expands the tube of the heat transfer tube 3. Since the flare punch 5 is press-fitted into the heat transfer tube 3 after reaching the deepest portion, the tip of the flare punch 5 is always inserted or press-fitted into the tube opening 3b of the heat transfer tube 3 even during the primary expansion, to leave a gap. Since the heat transfer tubes 3 are in contact with each other without having the core transfer, the desired flare processing 7 can be applied to the heat transfer tubes 3 at the end of the primary expansion without causing a core shift in the heat transfer tubes 3.

Further, according to the present invention, the heat transfer tube 3 is inserted through the plurality of heat radiating fins 2 which are overlapped with each other, and then the heat transfer tube 3 is projected from the heat radiating fins at one end side with a predetermined dimension from the tube opening 3b. The secondary pipe expanding mandrel 4 and at least the secondary pipe flaring punch 5 are press-fitted at the same time with a predetermined size to form a pipe mouth (3b).
After forming a slight flare portion 6 on the flare punch 5, only the flare punch 5 is stopped, and thereafter the flare punch is reached until the pipe expanding action portion of the primary pipe expanding mandrel 4 reaches the deepest pipe expanding portion of the heat transfer pipe 3. Since 5 is press-fitted into the heat transfer tube 3, the opening 3b of the heat transfer tube 3 is formed in the initial stage of the primary expansion.
It is possible to form a slight flare portion 6 on the inner surface of the primary expansion tube, so that the heat transfer tube 3 has a slight misalignment in the middle of the primary expansion tube so that the tube opening 3b approaches the peripheral surface of the primary expansion mandrel 4. Even if it is tilted, the tip of the flare punch 5 does not bite the mouth 3b of the heat transfer tube 3 with the tip of the flare punch 5, and the tip of the flare punch 5 is slightly inserted into the flare portion 6 to expand the desired flare processing 7 at the time of primary expansion. Can be applied to the heat transfer tube 3.

Further, according to the present invention, the heat transfer tube 3 is inserted through the plurality of heat radiating fins 2 which are overlapped with each other, and then the heat transfer tube 3 is projected from the heat radiating fin 3 on one end side with a predetermined size from the opening 3b.
The secondary expansion mandrel 4 and at least the secondary expansion flare punch 5 are press-fitted at the same time with a predetermined size, and are slightly inserted into the pipe opening 3b.
After forming the flare portion 6 of the flare punch 5, only the flare punch 5 is stopped, and after that, the pipe expanding action portion of the primary pipe expanding mandrel 4 reaches the deepest pipe expanding portion of the heat transfer pipe 3, and then the flare punch 5 is connected to the heat transfer pipe. Heat-transfer tube 3 by pressing into 3
Since the primary expansion and flare processing are applied to the tube, a slight flare portion 6 is formed at the opening 3b of the heat transfer tube 3 in the initial stage of the primary expansion.
Therefore, even when the heat transfer tube 3 has a large misalignment at the end of the primary expansion and the tube opening 3b is in contact with the peripheral surface of the primary expansion mandrel 4 and inclined, The tip of the flare punch 5 is slightly flared without biting the mouth 3b of the heat transfer tube 3 with the tip of the flare punch 5.
The desired flare processing 7 can be applied to the heat transfer tube 3 after the completion of the primary expansion.

Further, according to the present invention, the heat transfer tube 3 is inserted through the plurality of heat radiation fins 2 which are overlapped with each other, and the heat transfer tube 3 having a predetermined size is projected from the heat radiation tube 3 at one end side thereof. The secondary expansion mandrel 4 and the flare punch 5 capable of at least secondary expansion are simultaneously press-fitted to a predetermined size by press fitting them into the pipe opening 3b.
A state in which the flare punch 5 is abutted against the tube opening 3b of the heat transfer tube 3 whose entire length is reduced through expansion by the primary tube expansion mandrel 4 which is press-fitted into the heat transfer tube 3 thereafter. The flare punch 5 is moved in synchronism with the contraction of the heat transfer tube 3 while maintaining the above, and then the tube expansion action part of the primary tube expansion mandrel 4 reaches the tube expansion deepest part of the heat transfer tube 3 while Since the flare punch 5 is press-fitted into the heat transfer tube 3, the tip of the flare punch 5 is always press-fitted into a slight flare portion 6 formed in advance in the mouth 3b of the heat transfer tube 3 even during the primary expansion, so that a gap is formed. Since the heat transfer tubes 3 are brought into contact with each other without having them, the desired flare processing 7 can be applied to the heat transfer tube 3 at the time of primary expansion without causing the core shift of the heat transfer tube 3.

Further, according to the present invention, the heat transfer tube 3 is inserted through the plurality of heat radiating fins 2 which are overlapped with each other, and the heat transfer tube 3 is projected from the heat radiating fins on one end side with a predetermined size to the opening 3b.
The secondary expansion mandrel 4 and at least the secondary expansion flare punch 5 are press-fitted at the same time with a predetermined size, and are slightly inserted into the pipe opening 3b.
The flare portion 6 is formed, and then the flare punch 5 is brought into contact with the tube opening 3b of the heat transfer tube 3 whose overall length is reduced through expansion by the primary expansion mandrel 4 which is press-fitted into the heat transfer tube 3. While maintaining the flare punch 5, the flare punch 5 is moved in synchronization with the contraction of the heat transfer tube 3, and then the flare punch 5 is moved to the deepest part of the heat transfer tube 3 after the tube expanding action portion of the primary tube expanding mandrel 4 reaches the deepest tube expansion part of the heat transfer tube 3. Since the heat transfer tube 3 is subjected to primary expansion and flare processing by being press-fitted into the heat transfer tube 3, the tip of the flare punch 5 is always press-fitted into the tube opening 3b of the heat transfer tube 3 even during the primary expansion, thus leaving a gap. Since the heat transfer tubes 3 are brought into contact with each other without having them, the desired flare processing 7 can be applied to the heat transfer tubes 3 after the completion of the primary expansion without causing a core shift in the heat transfer tubes 3.

Further, according to the present invention, the flare punch 5 is
Since the pipe expanding action portion of the primary pipe expanding mandrel 4 is press-fitted into the heat transfer pipe 3 until it reaches from the substantially central portion of the heat transfer pipe 3 to the deepest pipe expanding portion, the heat radiating fins forming the heat exchanger. Approximately half of the heat transfer tube expanded by passing through the primary expansion mandrel 4 is integrally and firmly integrated, so that even if the flare punch 5 is press-fitted, distortion of the entire heat exchanger and Deformation can be reliably prevented.

[0018]

DETAILED DESCRIPTION OF THE INVENTION

<First Embodiment> A first embodiment for carrying out the method for manufacturing a heat exchanger according to the present invention will be described below with reference to the drawings.

In FIG. 1 (a), first, a primary pipe expanding mandrel 4 having a pipe expanding billet 4a attached to its tip is inserted into a plurality of polymerized heat radiating fins 2 and the heat radiating fins 2 on one end side. And a pipe expanding portion of the primary pipe expanding mandrel that is press-fitted (arrow G) from the pipe opening 3b of the projecting portion 3a of the heat transfer pipe 3 protruding from the end plate 8 with a predetermined size (expanding pipe). When the billet 4a) is located in the vicinity of the radiation fin 2 on the one end side, as shown in FIG.
Secondary flare molding part for forming secondary flare from the tube mouth 3b side
5a and a third flare molding portion 5b for forming a third flare are integrally provided, and a flare punch 5 for secondary and tertiary pipe expansion is press-fitted with a predetermined size (arrow H), and a slight flare portion 6 is formed in the pipe mouth 3b. The press-fitting of the flare punch 5 is stopped when the flare punch 5 is formed.

Thereafter, the primary expanding mandrel 4 is
As shown in FIG. 2 (a), the heat transfer tube 3 is further press-fitted (arrow I) to the deepest part of the heat transfer tube 3 to expand the heat transfer tube 3 substantially entirely, and both the plurality of heat radiation fins 2 and the end plate 8 are The heat transfer tube 3 is permanently combined with the heat transfer tube 3, but at this time, the total length of the heat transfer tube 3 shrinks by a predetermined dimension in the tube expansion direction of the primary tube expansion mandrel 4 due to the material sink associated with the tube expansion (arrow J). Rather, the strain is generated so as to slightly incline in the direction intersecting with the tube expanding direction, and the axis of the heat transfer tube 3 (arrow A) does not coincide with the axis of the primary tube expanding mandrel 4 (arrow B). (Arrow K) may be provided, but the mouth of the heat transfer tube 3
Since a slight flare portion 6 is formed in 3b, as shown in (b) and (c) of the same figure, the heat transfer tube 3 has a large misalignment at the end of the primary expansion and the tube opening 3b is formed. Even if the peripheral surface of the primary expanding mandrel 4 is in contact with and inclined, the flare punch 5 is slightly flared at the tip of the flare punch 5 without biting the mouth 3b of the heat transfer tube 3 with the tip of the flare punch 5. 6
Has a great advantage that the desired flare processing 7 can be applied to the heat transfer tube 3 after the completion of the primary expansion by pressing the flare punch 5 (arrow M).

<Second Embodiment> In the first embodiment, the flare punch 5 is formed after the tube expanding action portion of the primary tube expanding mandrel 4 expands substantially the entire heat transfer tube 3, that is, the tube expansion of the heat transfer tube 3. After reaching the deepest part, it is press-fitted into the heat transfer tube 3. However, this is not necessarily the case until the tube expanding action part of the primary tube expanding mandrel 4 reaches from the substantially central part of the heat transfer tube 3 to the deepest part. In addition, the flare punch 5 is connected to the heat transfer tube 3
May be press-fitted (not shown) in this case, and even in this case, the tip of the flare punch 5 can be inserted into a slight flare portion 6 formed in the tube opening 3b of the heat transfer tube 3 in the initial stage of the primary expansion. Therefore, even if the heat transfer tube 3 has a slight misalignment during the primary expansion and the tube opening 3b is inclined to approach the peripheral surface of the primary expansion mandrel 4, the tube of the heat transfer tube 3 mouth
There is an advantage that the desired flare processing 7 can be applied to the heat transfer tube 3 at the time of primary expansion without biting 3b at the tip of the flare punch 5.

<Third Embodiment> Further, in each of the above-described embodiments, the flare punch 5 has the deepest pipe expansion depth after the pipe expanding action portion of the primary pipe expanding mandrel 4 reaches the deepest pipe expanding portion of the heat transfer pipe 3. Heat transfer tube 3 before reaching the section
As shown in FIG. 3 (a), the primary expansion mandrel 4 is press-fitted from the pipe opening 3b of the heat transfer pipe 3 which has a predetermined dimension and protrudes from the heat radiation fin on one end side, as shown in FIG. While pressing (arrow N), the flare punch 5 is press-fitted (arrow O) from the pipe port 3b to a predetermined size, and then press-fitted (arrow P) into the heat transfer tube 3 as shown in FIG. Contraction of the flare punch 5 while maintaining the state in which the tip of the flare punch 5 is in contact with the tube mouth 3b of the heat transfer tube 3 whose overall length is reduced (arrow Q) through expansion by the primary tube expanding mandrel 4 After moving (arrow R) in synchronism with (arrow Q), the flare punch 5 is press-fitted into the heat transfer tube 3 after the tube expanding action portion of the primary tube expanding mandrel 4 reaches the tube expansion deepest portion of the heat transfer tube 3. However, in this case, even if the primary expansion is being performed, the heat transfer tube 3 always has the opening 3b. Since the tip of the flare punch 5 is press-fitted and abutted without a gap, the desired flare processing can be applied to the heat transfer tube 3 at the end of the primary expansion without causing a core shift in the heat transfer tube 3. However, the flare punch 5 does not necessarily have to be press-fitted into the heat transfer tube 3 after the tube expansion operation portion of the primary tube expansion mandrel 4 reaches the tube expansion deepest portion of the heat transfer tube 3, and the tube expansion operation portion has the tube expansion operation portion. The flare punch 5 may be press-fitted (not shown) into the heat transfer tube 3 before reaching the deepest part from the substantially central portion of the heat transfer tube 3. Even in this case, the tube opening of the heat transfer tube 3
Since the tip of the flare punch 5 is always press-fitted into 3b and abutted without a gap, the desired flare processing 7 can be performed without causing the core shift in the heat transfer tube 3, as shown in FIG. There is an advantage that it can be applied to the heat transfer tube 3 at the time of subsequent tube expansion.

<Fourth Embodiment> Further, as shown in FIG. 4 (a), the primary pipe expanding mandrel 4 and the flare punch 5 are simultaneously press-fitted into the heat transfer pipe 3 from the mouth 3b thereof with predetermined dimensions (arrow S).
Then, as shown in FIG. 6B, the overall length of the heat transfer tube 3 is reduced (arrow U) through expansion by the primary expansion mandrel 4 that is press-fitted (arrow T) into the heat transfer tube 3 (arrow U). While maintaining the state in which the flare punch 5 is in contact with 3b, the flare punch 5 is moved (arrow V) in synchronism with the contraction (arrow U) of the heat transfer tube 3, and then the pipe expanding action of the primary pipe expanding mandrel 4 is performed. After the portion reaches the deepest portion of the heat transfer tube 3 to expand the pipe, the flare punch 5 may be press-fitted (not shown) into the heat transfer tube 3 to perform primary expansion and flare processing on the heat transfer tube 3. In this case, even when the primary pipe is expanded, the tip of the flare punch 5 is always press-fitted into the pipe opening 3b of the heat transfer pipe 3 and abuts with no gap, so that the heat transfer pipe 3 is misaligned. Without the desired flare processing 7, see Fig. 2 (C).
As described above, the heat transfer tube 3 can be applied to the heat transfer tube 3 after the completion of the primary tube expansion. However, the flare punch 5 does not always transfer heat after the tube expansion action portion of the primary tube expansion mandrel 4 reaches the tube expansion deepest portion of the heat transfer tube 3. The flare punch 5 does not have to be press-fitted into the heat transfer tube 3, and even if the flare punch 5 is press-fitted (not shown) into the heat transfer tube 3 until the tube expansion action portion reaches from the substantially central portion of the heat transfer tube 3 to the deepest part of the tube expansion. Well, even in this case, the heat transfer tube 3
Since the tip of the flare punch 5 is always press-fitted into a slight flare portion 6 formed in the tube opening 3b of the tube, and the flare punch 5 is in contact with the flare punch 5 without a gap, a desired flare processing can be performed without causing misalignment of the heat transfer tube 3. Although there is an advantage that it can be applied to the heat transfer tube 3 at the time of primary expansion, as described above, the flare punch 5 is transferred while maintaining the state where the tip of the flare punch 5 is in contact with the tube mouth 3b without a gap. If the flare punch 5 is moved in synchronization with the shrinkage of the heat tube 3, the flare punch 5 does not necessarily have to be press-fitted in advance to form a slight flare portion 6 in the tube opening 3b of the heat transfer tube 3, and the flare of the flare punch 5 may be flared. The same advantages as described above by moving the flare punch 5 in synchronization with the shrinkage of the heat transfer tube 3 while maintaining the state in which the molding portion is inserted into the tube opening 3b and is in contact with the tube opening 3b without a gap. Have.

<Fifth Embodiment> Furthermore, in the method of manufacturing the heat exchanger according to the present invention, the primary pipe expanding mandrel 4 is press-fitted (not shown) from the pipe port 3b of the heat transfer pipe 3 while the pipe is being pressed. At least the flare punch 5 capable of secondary pipe expansion is pressed into the heat transfer pipe 3 from the mouth 3b to a predetermined size and stopped, and then the pipe expanding action portion of the primary pipe expanding mandrel 4 which is press-fitted into the heat transfer pipe 3 has a substantially central portion of the heat transfer pipe 3. The flare punch 5 may be press-fitted into the heat transfer tube 3 before reaching the deepest part of the tube, and even in this case, the flare punch 5 may be slightly inserted into the tube opening 3b of the heat transfer tube 3 during the primary expansion. It becomes possible to form the flare portion 6, and thus 1
The heat transfer tube 3 has a slight misalignment in the middle of the next tube expansion, and the tube mouth 3b
Even if the tip of the flare punch 5 is inclined to approach the peripheral surface of the primary expanding mandrel 4, the tip of the flare punch 5 can be slightly flared without biting the mouth 3b of the heat transfer tube 3 with the tip of the flare punch 5. Has the advantage that the desired flare processing can be applied to the heat transfer tube 3 at the time of the primary tube expansion, but the flare punch 5 has the tube expansion action part of the primary tube expansion mandrel 4 and the deepest tube expansion part of the heat transfer tube 3. After reaching the heat transfer tube 3, the heat transfer tube 3 may be subjected to primary expansion and flare processing by press fitting into the heat transfer tube 3, and even in this case, a slight flare portion 6 may be formed in the tube opening 3b of the heat transfer tube 3. Therefore, when the heat transfer tube 3 has a large misalignment at the end of the primary expansion and the tube mouth 3b is in contact with the peripheral surface of the primary expansion mandrel 4 and is inclined. Also, the tube mouth 3b of the heat transfer tube 3
There is a great advantage that the desired flare processing can be performed on the heat transfer tube 3 after the completion of the primary tube expansion by allowing the distal end of the flare punch 5 to slightly enter the flare portion 6 without being bitten by the distal end of the flare punch 5.

<Sixth Embodiment> Furthermore, in the method for manufacturing a heat exchanger according to the present invention, the heat transfer tube 3 is inserted through the plurality of heat radiation fins 2 which are overlapped with each other, and then the heat radiation fin on one end side has a predetermined size. The mandrel 4 for primary expansion and the flare punch 5 capable of at least secondary expansion are simultaneously press-fitted into the projecting port 3b of the heat transfer tube 3 having a predetermined size with a predetermined dimension, and then only the flare punch 5 is stopped. Next pipe expanding mandrel 4
The flare punch 5 may be press-fitted into the heat transfer tube 3 before the tube expansion action portion of the heat transfer tube 3 reaches from the substantially central portion to the deepest tube expansion portion. Since it is possible to form a slight flare portion 6 in the tube opening 3b of the heat transfer tube 3 in the initial stage of 1, the heat transfer tube 3 has a slight misalignment during the primary expansion and Even if the flaring punch 5 is inclined so as to approach the peripheral surface of the next pipe expanding mandrel 4, the flare punch 5 is slightly flared at the tip of the flare punch 5 without biting the mouth 3b of the heat transfer tube 3 with the tip of the flare punch 5.
Heat transfer tube 3 for the primary expansion when the desired flare is processed
However, the flare punch 5 is press-fitted into the heat transfer tube 3 after the tube expansion action portion of the primary tube expansion mandrel 4 reaches the deepest tube expansion portion of the heat transfer tube 3, 3 may be subjected to primary expansion and flare processing, and even in this case, it is possible to form a slight flare portion 6 at the opening 3b of the heat transfer tube 3 in the initial stage of primary expansion. Even when the heat transfer tube 3 has a large misalignment at the end of the primary expansion and the pipe opening 3b is in contact with the peripheral surface of the primary expansion mandrel 4 and inclined, the heat transfer tube 3
It is possible to apply the desired flare processing to the heat transfer tube 3 after the completion of the primary expansion by advancing the tip of the flare punch 5 into a slight flare portion 6 without biting the tube mouth 3b of the flare punch 5 with the tip. Have.

In each of the above-mentioned embodiments, the flare punch 5 has the heat transfer tube 3 during the time when the tube expansion action portion of the primary tube expansion mandrel reaches from the substantially central portion of the heat transfer tube to the deepest tube expansion portion.
Even if it is press-fitted into the pipe to form a desired flare, approximately half of the heat radiating fins forming the heat exchanger are integrally and firmly formed with the heat transfer pipe expanded by the passage of the primary pipe expanding mandrel 4. Since the heat exchanger as a whole has a great advantage that distortion and deformation of the entire heat exchanger can be reliably prevented, it is not necessarily an essential requirement of the present invention, and the point is that the flare punch 5 expands the mandrel for expanding the primary tube. Any structure may be adopted as long as the action portion reaches the deepest tube expansion portion of the heat transfer tube or after the deepest tube expansion portion is reached, the heat transfer tube 3 is press-fitted for secondary or secondary and tertiary flare processing.

Further, in each of the above-mentioned embodiments, the heat exchanger is composed of a plurality of heat radiation fins and an end plate, but the end plate is not always an essential requirement.
What is essential is that the heat exchanger is formed into a desired shape by superimposing a plurality of radiating fins, and the external shape of the heat exchanger, the number of radiating fins to be superposed, and the heat transfer tube inserted into the radiating fins. Needless to say, the total number and the insertion pattern are not limited.

Further, in each of the above embodiments, the flare punch integrally includes a secondary flare molding portion for forming a secondary flare and a tertiary flare molding portion for forming a tertiary flare 2,
Although the flare punch for tertiary expansion is used, the flare punch for secondary expansion is not necessarily limited to the flare punch for secondary expansion.
It may be a flare punch that can perform only the next flare process or a multi-stage flare process. In this case, it is possible to have versatility that can be applied to a wide variety of heat exchangers that are characterized by the flare part. There is.

[0029]

As described above, according to the present invention, a secondary flare for inserting a substantially U-shaped connecting pipe into the pipe opening of the heat transfer pipe provided with the primary expansion pipe of the heat exchanger, or In the case of press-fitting a predetermined flare punch into the tube mouth of the heat transfer tube at the time of primary expansion or at the time of completion of primary expansion, the heat transfer tube passes through the primary expansion mandrel. Due to the material sink during pipe expansion, the overall length shrinks in the pipe expansion direction, and distortion is generated to incline in the direction intersecting the pipe expansion direction, and there is a slight misalignment, and the pipe mouth approaches the peripheral surface of the primary pipe expanding mandrel. Even if the heat transfer tube is inclined as much as possible, or if the heat transfer tube has a large misalignment and the tube opening is in contact with the peripheral surface of the primary expanding mandrel and is inclined, the tube of the heat transfer tube The tip of the flare punch is slightly preformed on the tube mouth without biting the mouth with the tip of the flare punch. Has an excellent effect that is advanced to the flare portion desired flaring reliably performed it is possible to tube inlet of the heat transfer tubes.

Further, at the time of primary expansion, a slight flare portion is previously formed at the mouth of the heat transfer tube via a flare punch.
Thereafter, the flare punch is moved in synchronism with the contraction of the heat transfer tube while maintaining the state in which the flare punch is in contact with the opening of the heat transfer tube whose overall length is reduced through expansion by the primary expansion mandrel, and then the primary expansion tube After completion of the above, or during the primary expansion, the heat transfer tube may be subjected to primary expansion and flare processing by press-fitting a flare punch into the tube opening. In this case, even during primary expansion Since the tip of the flare punch is always press-fitted into the mouth of the heat transfer tube and comes into contact with it with no gap, the desired flare processing can always be applied to the heat transfer tube without causing any misalignment in the heat transfer tube. That is, it has an extremely excellent effect.

Therefore, according to the method of manufacturing the heat exchanger of the present invention, it is possible not only to eliminate the galling and the deformation defect during the secondary or secondary flare processing at the time of manufacturing the heat exchanger. It is said that it is possible to manufacture a heat exchanger of uniform quality with maximum efficiency by making only a slight change in the operating sequence without making any complicated modifications to the expansion device itself that has been used conventionally. It also has a special effect.

[Brief description of drawings]

FIG. 1 shows a relationship between a primary pipe expanding mandrel and a flare punch at the time of primary pipe expansion in a method for manufacturing a heat exchanger of the present invention, and FIGS. .

FIG. 2 shows a flow from a primary pipe expanding process to a flare process in the method for manufacturing a heat exchanger according to the present invention.
(B) and (C) are enlarged partial cross-sectional views of the main part.

FIG. 3 shows a relationship between a primary pipe expanding mandrel and a flare punch at the time of primary pipe expansion according to another embodiment of the method for manufacturing a heat exchanger, and FIGS. .

FIG. 4 shows a relationship between a primary pipe expanding mandrel and a flare punch at the time of primary pipe expansion according to another embodiment of the method for manufacturing a heat exchanger, and FIGS. .

FIG. 5 shows the relationship between the flare punch and the primary pipe expanding mandrel during the primary pipe expansion in the conventional heat exchanger manufacturing method.
The figures (a), (b), and (c) are enlarged partial cross-sectional views of the main part.

[Explanation of symbols]

1 ... Heat exchanger 2 ... Radiating fin 3 ... Heat transfer tube 3a ... projection 3b ... tube mouth 4 ... Primary pipe expanding mandrel 4a ... Expansion billet 5 ... flare punch 6 ... Slight flare 7… 2, 3rd flare 8 ... End plate 9 ... biting A ... Virtual line of heat transfer tube axis B: Virtual line of the shaft center of the primary expansion mandrel

Continuation of front page (56) Reference JP-A-59-110438 (JP, A) JP-A-58-9732 (JP, A) JP-A-6-234031 (JP, A) JP-A-57-97831 (JP , A) Actually open 52-34839 (JP, U) Actually open 6-29736 (JP, U) Actually open 5-84441 (JP, U) Actually open 4-83428 (JP, U) (58) Fields surveyed (Int.Cl. ⁷ , DB name) B21D 53/08 B21D 19/08 B21D 39/20 B21D 41/02

Claims (11)

(57) [Claims] 1. A heat transfer tube (3) is inserted through a plurality of polymerized heat dissipation fins (2), and a pipe opening (3) of the heat transfer tube (3) projecting from the heat dissipation fin at one end side thereof has a predetermined dimension. When the primary pipe expanding mandrel (4) is press-fitted from 3b) and the pipe expanding action portion of the tip of the primary pipe expanding mandrel press-fitted thereafter is located in the vicinity of the radiation fin on the one end side, the pipe mouth (3b) At least a secondary flare punch (5) capable of secondary expansion is press-fitted with a predetermined size.
Then, when a slight flare portion (6) is formed in the tube mouth (3b), the tube is stopped and then the primary pipe expanding mandrel (4) is attached to the heat transfer tube.
(3) Press-fit into the mandrel for primary expansion (4)
The flare punch (5) is press-fitted into the heat transfer tube (3) until the tube expansion action part of the heat transfer tube (3) reaches the deepest part of the tube expansion of the heat transfer tube (3). A method of manufacturing a heat exchanger, characterized by performing flare processing. 2. The heat transfer tube (3) is inserted through the plurality of polymerized heat dissipation fins (2), and then the heat transfer tube (3) has a predetermined size and protrudes from the heat dissipation fin at one end side of the heat transfer tube (3). When the primary pipe expanding mandrel (4) is press-fitted from 3b) and the pipe expanding action portion of the tip of the primary pipe expanding mandrel press-fitted thereafter is located in the vicinity of the radiation fin on the one end side, the pipe mouth (3b) At least a secondary flare punch (5) capable of secondary expansion is press-fitted with a predetermined size.
Then, when a slight flare portion (6) is formed in the tube mouth (3b), the tube is stopped and then the primary pipe expanding mandrel (4) is attached to the heat transfer tube.
(3) Press-fit into the mandrel for primary expansion (4)
After the tube expansion action part of has reached the tube expansion deepest part of the heat transfer tube (3), the flare punch (5) is pressed into the heat transfer tube (3) to perform primary tube expansion and flare processing on the heat transfer tube (3). A method for manufacturing a heat exchanger, which comprises applying the heat exchanger. 3. A heat transfer tube (3) is inserted through a plurality of polymerized heat dissipation fins (2), and then the heat transfer tube (3) protruding from the heat dissipation fin (2) at one end side has a predetermined size. From the mouth (3b) 1
While press-fitting the secondary pipe expanding mandrel (4), press the flare punch (5) capable of at least secondary pipe expansion from the pipe port (3b) to a predetermined size , and slightly flare part (6) into the pipe port (3b). To form
At that point, the pipe expanding action part of the primary pipe expanding mandrel (4), which is then press-fitted into the heat transfer pipe (3), is the heat transfer pipe.
The heat transfer tube (3) is inserted by press-fitting the flare punch (5) into the heat transfer tube (3) before reaching the deepest part of the expansion of (3).
A method for manufacturing a heat exchanger, characterized in that the tube is subjected to primary expansion and flare processing. 4. The heat transfer tube (3) is inserted through the plurality of polymerized heat dissipation fins (2), and then the heat transfer tube (3) protruding from the heat dissipation fin (2) on one end side has a predetermined size. From the mouth (3b) 1
While press-fitting the secondary pipe expanding mandrel (4), press the flare punch (5) capable of at least secondary pipe expansion from the pipe port (3b) to a predetermined size , and slightly flare part (6) into the pipe port (3b). To form
At that point, the pipe expanding action part of the primary pipe expanding mandrel (4), which is then press-fitted into the heat transfer pipe (3), is the heat transfer pipe.
After reaching the deepest part of pipe expansion in (3), the flare punch
By pressing (5) into the heat transfer tube (3), 1 is inserted into the heat transfer tube (3).
A method of manufacturing a heat exchanger, characterized by subjecting to secondary expansion and flaring. 5. The heat transfer tube (3) is inserted through the plurality of polymerized heat dissipation fins (2), and then the heat transfer tube (3) is projected with a predetermined size from the heat dissipation fin at one end side. While press-fitting the primary pipe expanding mandrel (4) from 3b), at least the flare punch (5) capable of secondary pipe expansion is inserted or pressed into the pipe port (3b) from the pipe port (3b) to a predetermined size. Shape the flare part 6 of
Heat transfer tube that is formed and then shrinks in its overall length through expansion by the primary expansion mandrel (4) that is press-fitted into the heat transfer tube (3)
While maintaining the flare punch (5) in contact with the tube mouth (3b) of (3), the flare punch (5) is moved in synchronization with the contraction of the heat transfer tube (3), and then the primary expansion tube For mandrel
The flare punch (5) is moved to the heat transfer tube until the tube expansion action part (4) reaches the deepest tube expansion part of the heat transfer tube (3).
A heat exchanger manufacturing method characterized in that the heat transfer tube (3) is subjected to primary expansion and flare processing by being press-fitted into (3). 6. A heat transfer tube (3) is inserted through a plurality of polymerized heat dissipation fins (2), and then the heat transfer tube (3) has a predetermined opening and protrudes from the heat dissipation fin (3). While press-fitting the primary pipe expanding mandrel (4) from 3b), insert or press-fit the flare punch (5) capable of at least secondary pipe expanding to a predetermined size from the pipe port (3b) and slightly press it into the pipe port (3b). Shape the flare part (6) of
Heat transfer tube that is formed and then shrinks in its overall length through expansion by the primary expansion mandrel (4) that is press-fitted into the heat transfer tube (3)
While maintaining the flare punch (5) in contact with the tube mouth (3b) of (3), the flare punch (5) is moved in synchronization with the contraction of the heat transfer tube (3), and then the primary expansion tube For mandrel
After the tube expansion action part of (4) reaches the tube expansion deepest part of the heat transfer tube (3), the flare punch (5) is press-fitted into the heat transfer tube (3) to perform a primary tube expansion into the heat transfer tube (3). A method of manufacturing a heat exchanger, characterized by performing flare processing. 7. A heat transfer pipe (3) is inserted through a plurality of polymerized heat dissipation fins (2), and a pipe opening (3) of the heat transfer pipe (3) protruding with a predetermined dimension from the heat dissipation fin on one end side is then formed. From 3b), the mandrel for primary expansion (4) and at least the flare punch (5) capable of secondary expansion are simultaneously pressed into the pipe mouth (3b) with a predetermined size.
After forming the dried flare part (6), only the flare punch (5) is stopped, and then the pipe expanding action part of the primary pipe expanding mandrel (4) reaches the deepest pipe expanding part of the heat transfer pipe (3). In the meantime, the method for producing a heat exchanger, characterized in that the flare punch (5) is press-fitted into the heat transfer tube (3) to subject the heat transfer tube (3) to primary expansion and flare processing. 8. The heat transfer tube (3) is inserted through a plurality of polymerized heat dissipation fins (2), and then the heat transfer tube (3) has a predetermined opening and protrudes from the heat dissipation fin (3). From 3b), the mandrel for primary expansion (4) and at least the flare punch (5) capable of secondary expansion are simultaneously pressed into the pipe mouth (3b) with a predetermined size.
After forming the dried flare part (6), only the flare punch (5) was stopped, and then the pipe expanding action part of the primary pipe expanding mandrel (4) reached the deepest pipe expanding part of the heat transfer pipe (3). After that, the flare punch (5) is press-fitted into the heat transfer tube (3) to perform primary expansion and flare processing on the heat transfer tube (3). 9. The heat transfer tube (3) is inserted through a plurality of polymerized heat radiation fins (2), and then the heat transfer tube (3) is projected with a predetermined dimension from the heat radiation fin on one end side. The primary expansion mandrel (4) and at least the secondary expansion flare punch (5) from 3b) are pressed into the pipe opening (3b) at the same time by press-fitting with a predetermined size.
The tube mouth (3b) of the heat transfer tube (3), which forms a dried flare part (6) and then shrinks in its overall length through expansion by the primary tube expansion mandrel (4) that is press-fitted into the heat transfer tube (3). To the flare punch
The flare punch (5) while maintaining the state in which (5) is in contact.
Move in synchronization with the contraction of the heat transfer tube (3),
The tube expansion action part of the secondary tube expansion mandrel (4) is the heat transfer tube (3).
Before reaching the deepest part of the pipe expansion,
By pressing (5) into the heat transfer tube (3), 1 is inserted into the heat transfer tube (3).
A method of manufacturing a heat exchanger, characterized by subjecting to secondary expansion and flaring. 10. A heat transfer tube (3) is inserted through a plurality of polymerized heat dissipation fins (2), and then the heat transfer tube (3) has a predetermined opening and protrudes from the heat dissipation fin (3). From 3b), the primary expansion mandrel (4) and at least the secondary expansion flare punch (5) are pressed into the pipe mouth (3b) at the same time with a predetermined size.
The heat transfer tube (3b) has a slight flare part (6), and then the heat transfer tube (3) is expanded by a primary expansion mandrel (4) that is press-fitted into the heat transfer tube (3). While maintaining the state in which the flare punch (5) is in contact with the flare punch (5),
(5) is moved in synchronism with the contraction of the heat transfer tube (3), and then the tube expanding action part of the primary tube expanding mandrel (4) is moved to the heat transfer tube.
After reaching the deepest part of pipe expansion in (3), the flare punch
By pressing (5) into the heat transfer tube (3), 1 is inserted into the heat transfer tube (3).
A method of manufacturing a heat exchanger, characterized by subjecting to secondary expansion and flaring. 11. The heat transfer tube of the flare punch (5) until the tube expansion action portion of the primary tube expansion mandrel (4) reaches the deepest tube expansion area from the substantially central portion of the heat transfer tube (3).
It is press-fitted in (3).
7. A method for manufacturing a heat exchanger according to 7, 9.