JP4631345B2 - Tube expansion device - Google Patents

Description

  The present invention relates to a tube expansion device.

In manufacture of a heat exchanger, a heat exchanger tube is passed through the fins laminated with a predetermined fin pitch. Then, a mandrel is inserted into the heat transfer tube penetrating the fins, thereby expanding the diameter of the heat transfer tube and fixing the heat transfer tube and the fin (see Patent Document 1).
JP-A-6-65415

  When the tube expansion process is started, the heat transfer tube in which the mandrel is inserted is expanded in the outer shape. That is, when the mandrel is inserted from one end of the heat transfer tube, a difference occurs between the tube diameter of the portion where the mandrel has already passed and the tube diameter of the portion where the mandrel has not yet passed. And the fin located in the outer side of a heat exchanger tube is pressed to the direction in which the spreading deformation of the heat exchanger tube has not yet arisen, ie, the other end side of a heat exchanger tube. For this reason, the fin pitch of the fin located in the other end side of a heat exchanger tube is small, the fin density of the other end side becomes larger than the fin density of the one end side, and there exists a possibility that a deviation may arise in a fin pitch. As described above, in the conventional pipe expanding device, it is difficult to make the distribution of the fin pitch into a desired mode due to the influence of the deformation of the fin during the pipe expansion.

  The subject of this invention is providing the pipe expansion apparatus which can adjust a fin pitch to a desired state in a pipe expansion process.

A tube expansion device according to a first aspect of the present invention is a heat exchanger comprising a plurality of stacked fins provided with a plurality of holes and a plurality of heat transfer tubes inserted into the holes and penetrating the fins, and inserted into the fin holes. A tube expansion device that expands a heat transfer tube and fixes a fin and a heat transfer tube, the plurality of mandrels, a moving member , a mandrel driving unit that drives the mandrel, a moving member driving unit that drives the moving member, and a mandrel A control unit that controls the driving unit and the moving member driving unit ; The plurality of mandrels are inserted into the heat transfer tubes from one end side of the plurality of heat transfer tubes to expand the heat transfer tubes. The moving member is movable in a first direction from one end side to the other end side of the heat transfer tube and in a second direction from the other end side to the one end side of the heat transfer tube, and is provided so as to support the fins. The control unit moves the moving member in the second direction and pushes the fins in the second direction before the mandrel is inserted into the heat transfer tube. Further, the control unit moves the mandrel in the first direction and inserts the mandrel into the heat transfer tube, and then moves the moving member in the first direction.

  In this pipe expansion device, since the moving member can support the fins, the pressing force received by the fins by the pipe expansion can be supported by the moving members. Since the moving member is movable in the first direction and the second direction, the movement amount of the fin can be adjusted and the fin pitch can be adjusted by adjusting the position of the moving member. Thereby, in this pipe expansion apparatus, a fin pitch can be adjusted to a desired state in a pipe expansion process.

  Further, the position of the moving member can be automatically adjusted by controlling the moving member driving unit by the control unit. Thereby, in this pipe expansion apparatus, adjustment of the fin pitch by a moving member can be performed more appropriately.

  Further, since the moving member is pushed in the second direction before the mandrel is inserted, the fins are densely arranged in the second direction. For this reason, when the fin is pressed in the first direction by inserting the mandrel, the fins that are densely arranged on the second direction side expand in the first direction. Thereby, in this pipe expansion apparatus, a fin pitch can be closely approached.

  Furthermore, since the moving member is moved in the first direction after the mandrel is inserted into the heat transfer tube, the fins that are densely arranged in advance in the second direction may spread in the first direction due to the insertion of the mandrel. It is possible to make the fin pitch close to uniform.

  The tube expansion device according to the second invention is the tube expansion device of the first invention, and the moving member can support the fin located on the most other end side of the heat transfer tube among the plurality of fins.

  In this pipe expansion device, the moving member can support the fin located on the most other end side of the heat transfer tube. For this reason, the movement to the other end direction of the fin which arises for insertion of a mandrel can be controlled. Thereby, in this pipe expansion apparatus, a fin pitch can be adjusted to a desired state in a pipe expansion process.

The tube expansion device according to the third invention is the tube expansion device of the first invention, and the control unit moves the moving member in the first direction as the mandrel advances in the heat transfer tube in the first direction.

  In this pipe expansion device, the moving member is moved in the first direction as the mandrel advances in the first direction. For this reason, the moving member can move in the first direction while restricting the movement of the fin in the first direction, and can suppress the fin from moving excessively in the first direction. Thereby, in this pipe expansion apparatus, fin pitch can be adjusted more accurately.

A tube expansion device according to a fourth invention is the tube expansion device of the first invention, wherein the control unit moves the mandrel in the first direction and inserts the mandrel into the heat transfer tube, and then controls the moving member driving unit to move the moving member. Reduces the pressing force applied to the fin in the second direction.

  In this pipe expansion device, after the mandrel is inserted into the heat transfer tube, the pressing force in the second direction that the moving member applies to the fin is reduced. For this reason, a moving member naturally moves to a 1st direction by the pressing force to the 1st direction which a fin receives by a deformation | transformation of a heat exchanger tube. Thereby, the fins densely arranged in the second direction spread in the first direction, and the fin pitch can be made closer to uniform.

A tube expansion device according to a fifth invention is the tube expansion device according to the first invention, wherein the control unit moves the mandrel in the first direction and inserts the mandrel into the heat transfer tube, and then the mandrel advances the heat transfer tube in the first direction. Initially, the moving member is moved in the second direction to push the fins in the second direction.

  In this pipe expansion device, the fins are pushed toward the second direction at the initial stage when the mandrel advances in the first direction and are densely arranged on the second direction side. For this reason, when the mandrel further advances in the first direction, the fins that are densely arranged on the second direction side spread in the first direction. Thereby, in this pipe expansion apparatus, a fin pitch can be closely approached.

In the tube expansion device according to the first aspect of the invention, the pressing force received by the fins by the tube expansion can be supported by the moving member, and the fin pitch can be adjusted by adjusting the position of the moving member. Thereby, in this pipe expansion apparatus, a fin pitch can be adjusted to a desired state in a pipe expansion process. Further, by controlling the moving member driving unit by the control unit, the fin pitch can be adjusted more appropriately by the moving member. Further, the fin pitch can be made close to uniform. Furthermore, fins that are densely arranged in advance in the second direction can be expanded in the first direction by inserting a mandrel, and the fin pitch can be made uniform.

  In the tube expansion device according to the second aspect of the present invention, the movement of the fins for inserting the mandrel in the other end direction can be restricted by the moving member. Thereby, in this pipe expansion apparatus, a fin pitch can be adjusted to a desired state in a pipe expansion process.

In the pipe expansion device according to the third aspect of the invention, the moving member can suppress the fin from moving excessively in the first direction, and can adjust the fin pitch more accurately.

In the pipe expansion device according to the fourth aspect of the invention, the fins that are densely arranged in the second direction spread in the first direction, and the fin pitch can be made uniform.

In the pipe expansion device according to the fifth aspect of the invention, the fins are pushed toward the second direction at the initial stage when the mandrel advances in the first direction and are densely arranged on the second direction side, so that they are densely arranged on the second direction side. Fins spread in the first direction. Thereby, in this pipe expansion apparatus, a fin pitch can be closely approached.

<First Embodiment>
<Structure of tube expansion device>
A tube expansion device 1 according to a first embodiment of the present invention is shown in FIG. The tube expansion device 1 is a device that expands a heat transfer tube penetrating a fin and fixes the heat transfer tube and the fin in the manufacturing process of the heat exchanger, and the heat exchanger so that the heat transfer tube is parallel to the vertical direction. 2 is a so-called vertical tube expansion device. As shown in FIG. 2, the heat exchanger 2 expanded by the tube expansion device 1 includes two fixing plates 21 and 22, a plurality of fins 23, and a plurality of heat transfer tubes 24. The two fixed plates 21 and 22 are provided in parallel with each other in the vicinity of the end of the heat exchanger 2, and a hole through which the heat transfer tube 24 passes is provided. The plurality of fins 23 are stacked in parallel between the two fixing plates 21 and 22, and a plurality of holes through which the heat transfer tubes 24 pass are provided. The heat transfer tube 24 passes through the fixing plates 21 and 22 and the fins 23 perpendicular to the fixing plates 21 and 22 and the fins 23. The lower ends of the heat transfer tubes 24 are connected to each other by a U-shaped tube 25, and the upper ends are open ends. Moreover, the heat exchanger 2 which is the target of the pipe expansion process by the pipe expansion device 1 is a so-called two-row heat exchanger, and the heat transfer tubes 24 are arranged in two rows as shown in FIG. That is, the heat exchanger 2 is parallel to the first straight line L1 in the first row heat transfer tube group G1 having a plurality of heat transfer tubes 24 arranged so as to be arranged at equal intervals on the first straight line L1 in the axial cross section. A second row heat transfer tube group G2 having a plurality of heat transfer tubes 24 arranged at equal intervals on the second straight line L2 and a plurality of pipes connecting the lower ends of the plurality of heat transfer tubes 24 of the first row heat transfer tube group G1 to each other. The first U-shaped tube U1, the plurality of second U-tubes U2 connecting the lower ends of the plurality of heat transfer tubes 24 of the second row heat transfer tube group G2, the lower end of the heat transfer tubes 24 of the first row heat transfer tube group G1, and the second A plurality of third U-shaped tubes U3 are connected to the lower ends of the heat transfer tubes 24 of the row heat transfer tube group G2. In addition, the diameter of the heat transfer tube 24 before the pipe expansion process is slightly smaller than the holes provided in the fins 23 and the fixing plates 21 and 22, and the heat transfer pipe 24 and the fins 23 are fixed to each other when the heat transfer pipe 24 is subjected to the pipe expansion process. The

  Returning to FIG. 1, the tube expansion device 1 includes a frame 3, a plurality of mandrels 4, a mandrel driving unit 5, a first fixing unit 6, a second fixing unit 7, a moving member 8 (see FIG. 5), and a moving member driving unit 9 ( 6) and a control unit 10 (see FIG. 6).

[flame]
The frame 3 includes a base 31, a guide post 32, a mandrel guide body 33, an upper frame 34, intermediate plates 35 and 36, a rod 37, a side support plate 38, and the like. The base 31 constitutes the bottom of the frame 3, and four guide posts 32 are erected at four corners of the base 31. The guide post 32 is a columnar member extending in the vertical direction. The mandrel guide 33 is a member that guides the mandrel 4 described later, and is provided at an intermediate portion of the guide post 32. The intermediate plates 35 and 36 are members that guide the mandrel 4 in the same manner as the mandrel guide body 33, and have a first intermediate plate 35 and a second intermediate plate 36 that are arranged separately in the vertical direction. The intermediate plates 35 and 36 are provided between the mandrel guide body 33 and the upper frame 34 so as to be slidable with respect to the guide post 32, and are connected to each other by a rod 37. The mandrel guide body 33 and the intermediate plates 35 and 36 are provided with a hole through which the mandrel 4 passes at a position corresponding to the mandrel 4, and the mandrel 4 inserted into the hole is restricted from moving in the horizontal direction. 4 is supported. The upper frame 34 constitutes the top of the frame 3 and the upper end of the guide post 32 is connected and fixed. The side support plate 38 is a member that supports the heat exchanger 2 placed on a cradle 71 described later from the side, and is fixed to the guide post 32.

[Mandrel]
The mandrels 4 are members inserted into the heat transfer tubes 24, and a plurality of mandrels 4 are provided corresponding to the number of the plurality of heat transfer tubes 24. Each of the plurality of mandrels 4 has a bar shape parallel to the vertical direction, and is provided so as to be movable in the vertical direction. A head portion 41 to be inserted into the heat transfer tube 24 is provided at the lower end of the mandrel 4, and the head portion 41 has a spherical shape with a larger diameter than other portions.

[Mandrel drive]
The mandrel driving unit 5 is a mechanism that moves the mandrel 4 in the vertical direction, and includes a main cylinder 51, a pressure frame 52, a pressing member 53, and the like. The main cylinder 51 is fixed to the upper frame 34 and has a cylinder body 54 that can be driven in the vertical direction. The pressure frame 52 is fixed to the tip of the cylinder body 54, and is slidably supported on the guide post 32 between the upper frame 34 and the intermediate plates 35 and 36. The pressing member 53 is attached to the pressure frame 52, and the plurality of mandrels 4 are attached to the lower surface of the pressing member 53 downward at a predetermined interval. Accordingly, when the cylinder body 54 of the main cylinder 51 is driven up and down, the pressure frame 52 and the pressing member 53 move up and down, and the mandrel 4 moves up and down accordingly.

[First fixed part]
The first fixing portion 6 is a portion that holds and fixes the upper end of the heat transfer tube 24, below the mandrel guide body 33, and in the vicinity of the upper end of the heat transfer tube 24 of the heat exchanger 2 installed in the tube expansion device 1. Is provided. As shown in FIG. 2, the first fixing portion 6 is configured by a clamp body that is provided so that the upper end of the heat transfer tube 24 can be clamped from a direction perpendicular to the axis, that is, from the horizontal direction. The heat transfer tube 24 is held by sandwiching the upper end from the horizontal direction.

[Second fixing part]
Returning to FIG. 1, the second fixing portion 7 is a portion that is locked and held by the U-shaped tube 25 that connects the lower end of the heat transfer tube 24, and is installed in the tube expansion device 1 above the base 31. It is provided in the vicinity of the U-shaped tube 25 of the heat exchanger 2. The 2nd fixing | fixed part 7 has the base 71, the shrinkage | contraction prevention pin 72 (refer FIG. 3), and the shrinkage | contraction prevention pin receiving member 73 (refer FIG. 3).

  The cradle 71 is provided on the base 31, and the heat exchanger 2 installed in the pipe expansion device 1 is placed thereon. A plurality of recesses into which the U-shaped tube 25 is fitted are provided on the upper surface of the cradle 71.

  As shown in FIG. 3, the plurality of shrinkage prevention pins 72 are rod-like members arranged in parallel to each other, and have a semicircular cross section (see FIG. 2). The plurality of anti-shrink pins 72 are provided so as to be movable at least in the horizontal direction, are respectively inserted inside the plurality of U-shaped tubes 25, and are respectively engaged with the plurality of U-shaped tubes 25 to lock the U-shaped tube 25. Support each from the inside. The plurality of shrinkage prevention pins 72 are inserted into the U-shaped tube 25 from a direction inclined with respect to a direction perpendicular to the U-shaped tube 25. Hereinafter, some of the plurality of anti-shrink pins 72 will be described in detail with reference to FIG. 4 which is an enlarged view of a part of the anti-shrink pins 72 and the vicinity of the U-shaped tube 25 to which the anti-shrink pins 72 are locked.

  As described above, the plurality of heat transfer tubes 24 are arranged in two rows of the first row heat transfer tube group G1 and the second row heat transfer tube group G2, and the first row heat transfer tube group G1 is arranged in the axial cross-sectional view. It has the 1st heat exchanger tube P1, the 2nd heat exchanger tube P2, the 3rd heat exchanger tube P3, and the 4th heat exchanger tube P4 arranged in order on the 1 straight line L1 at predetermined intervals. The second row heat transfer tube group G2 includes a fifth heat transfer tube P5, a sixth heat transfer tube P6, a seventh heat transfer tube P7, and an eighth heat transfer tube P8 that are arranged in order on the second straight line L2 with a predetermined interval in the axial sectional view. And have. The fifth heat transfer tube P5 is disposed away from the first heat transfer tube P1 in a direction that forms an angle α with the first straight line L1. The angle α is an angle in a range of 0 <α <90, and is about 60 degrees in FIG. The sixth heat transfer tube P6 is disposed away from the second heat transfer tube P2 in a direction that forms an angle α with the first straight line L1. The seventh heat transfer tube P7 is arranged away from the third heat transfer tube P3 in a direction that forms an angle α with the first straight line L1. The eighth heat transfer tube P8 is arranged away from the fourth heat transfer tube P4 in a direction that forms an angle α with the first straight line L1. The first row heat transfer tube group G1 and the second row heat transfer tube group G2 are alternately arranged as viewed from the direction perpendicular to the first straight line L1 and the second straight line L2 (see the solid line arrow A1 in the figure). That is, when viewed from the direction perpendicular to the first straight line L1 and the second straight line L2, the sixth heat transfer pipe P6 is located between the first heat transfer pipe P1 and the second heat transfer pipe P2, and the seventh heat transfer pipe P7. Is located between the second heat transfer tube P2 and the third heat transfer tube P3, and the eighth heat transfer tube P8 is located between the third heat transfer tube P3 and the fourth heat transfer tube P4. In other words, the first heat transfer pipe P1 is located between the fifth heat transfer pipe P5 and the sixth heat transfer pipe P6 when viewed from the direction perpendicular to the first straight line L1 and the second straight line L2, The heat transfer tube P2 is located between the sixth heat transfer tube P6 and the seventh heat transfer tube P7, and the third heat transfer tube P3 is located between the seventh heat transfer tube P7 and the eighth heat transfer tube P8. Moreover, the 1st heat exchanger tube P1 and the 2nd heat exchanger tube P2 are connected by the 1st U-shaped tube U1. The sixth heat transfer tube P6 and the seventh heat transfer tube P7 are connected by a second U-shaped tube U2. The third heat transfer tube P3 and the eighth heat transfer tube P8 are connected by a third U-shaped tube U3. Accordingly, the first U-shaped tube U1 is disposed along the first straight line L1, the second U-shaped tube U2 is disposed along the second straight line L2, whereas the third U-shaped tube U3 is disposed along the first straight line L1. And they are arranged obliquely across the second straight line L2. The plurality of shrinkage prevention pins 72 pass between the fifth heat transfer pipe P5 and the sixth heat transfer pipe P6 and are inserted into the first U-shaped pipe U1 and the inner side of the second U-shaped pipe U2. Is inserted into the second heat transfer tube P2 and the third heat transfer tube P3, passes between the seventh heat transfer tube P7 and the eighth heat transfer tube P8, and the inside of the third U-shaped tube U3. And a third shrinkage prevention pin 83 that passes between the third heat transfer tube P3 and the fourth heat transfer tube P4. The plurality of anti-shrink pins 81-83 are arranged at an angle α with respect to the first straight line L1, respectively. The first anti-shrink pins 81, the second anti-shrink pins 82, and the third anti-shrink pins 83 are The first straight line L1 is inserted into the first U-shaped tube U1, the second U-shaped tube U2, and the third U-shaped tube U3 from the direction that forms an angle α. The anti-shrink pins 81-83 are inserted inside the U-tube U1-U3 until the tip protrudes on the opposite side of the U-tube U1-U3.

  Returning to FIG. 3, the shrinkage prevention pin receiving member 73 is a member that receives the tip of the shrinkage prevention pin 72 inserted inside the U-shaped tube 25. The anti-shrinkage pin receiving member 73 is provided with a plurality of holes into which the tips of the plurality of anti-shrink pins 72 inserted respectively inside the plurality of U-shaped tubes 25 are inserted. Supports the tip of the anti-shrink pin 72 inserted into the hole and restricts the movement of the anti-shrink pin 72.

[Moving member and moving member driving unit]
The moving member 8 shown in FIG. 5 is movable in the vertical direction and is driven by the moving member drive unit 9 (see FIG. 6). The moving member 8 is a plate-like member parallel to a horizontal plane provided below the fins 23 positioned at the lowermost end, and is provided so as to be able to support the fins 23 from below. The moving member 8 is divided into two in the horizontal direction, each having a shape that is long in the longitudinal direction of the fins 23, and is arranged in parallel with the first straight line L1. The moving member 8 is disposed so as to sandwich the heat transfer tube 24 therebetween, and close to the heat transfer tube 24 from both sides of the side where the first row heat transfer tube group G1 is arranged and the side where the second row heat transfer tube group G2 is arranged. Arranged.

  6 includes, for example, a servo motor and a transmission mechanism that converts the rotation of the servo motor into a vertical movement of the moving member 8, and moves the moving member 8 upward and downward. Move.

[Control unit]
The control unit 10 shown in FIG. 6 controls the mandrel driving unit 5 and the moving member driving unit 9 to move the mandrel 4 and the moving member 8. The contents of control of the mandrel 4 and the moving member 8 by the control unit 10 will be described in detail later.

<Operation in tube expansion processing>
Operation | movement when performing a pipe expansion process with the pipe expansion apparatus 1 concerning this embodiment is demonstrated.

  First, the pressure frame 52 rises to the upper limit position, and the first fixing portion 6 is opened. Next, the heat exchanger 2 that has not been subjected to the pipe expansion process is placed on the cradle 71 with the open end of the heat transfer tube 24 facing up. At this time, the heat transfer tube 24 is located on the axial extension of the mandrel 4. And while fixing the upper end of the heat exchanger tube 24 with the clamp body of the 1st fixing | fixed part 6, it is U until the front-end | tip is inserted in the hole of the anti-shrinkage pin base 71 of the anti-shrinkage pin 72 of the 2nd fixing | fixed part 7. Insert inside the tube 25. Thereby, the setting of the heat exchanger 2 is completed. Further, the moving member 8 is installed below the lowermost fin 23 of the heat exchanger 2.

  When the setting of the heat exchanger 2 is completed and the tube expansion process is started, the control unit 10 controls each component as follows.

  First, as shown in FIGS. 7A and 7B, the moving member 8 moves upward (second direction, see arrow A2 in the figure), and the fin 23 positioned at the lowermost end moves upward. The plurality of fins 23 are pushed up and pushed upward as a whole. At this time, the distance (D2) by which the lowermost fin 23 is pushed up is preferably about 3 to 5% of the total length of the stacked fins 23 in the vertical direction, that is, the distance D1 between the fixed plates 21 and 22. . For example, when the total length of the fin is 800 mm, it is desirable that the distance by which the fin 23 is pushed up by the moving member 8 is about 30 to 40 mm.

  Next, the mandrel 4 moves downward. At this time, the main cylinder 51 is driven and the pressure frame 52 is lowered. As a result, the mandrel 4 is lowered and the head portion 41 is inserted into the heat transfer tube 24. While the heat transfer tube 24 is expanded by the mandrel 4, a compressive force is applied to the heat transfer tube 24 to contract in the axial direction, that is, in the vertical direction, but the first fixing portion 6 and the second fixing portion 7 cause the heat transfer tube 24 to expand. Since both ends are fixed, contraction of the heat transfer tube 24 is prevented. Then, as shown in FIG. 7C, after the mandrel 4 is moved downward and inserted into the heat transfer tube 24, when the mandrel 4 is positioned in the middle of the heat transfer tube 24, the moving member 8 is The movement in the downward direction (first direction, see arrow A3 in the figure) is started. Then, as the mandrel 4 moves downward in the heat transfer tube 24, the moving member 8 moves downward according to the movement of the mandrel 4.

  Returning to FIG. 1, when the pressure frame 52 is lowered to the position of the upper intermediate plates 35 and 36, the upper first intermediate plate 35 is also lowered by being pressed by the pressure frame 52. The pressure frame 52 and the first intermediate plate 35 are both lowered to the position of the lower second intermediate plate 36. Finally, the pressure plate, the first intermediate plate 35, and the second intermediate plate 36 are moved to the mandrel guide frame 33. The moving member 8 is also lowered to the lower limit position, and the tube expansion process is completed. When the tube expansion process is completed, the pressure frame 52 is raised and the mandrel 4 is extracted from the heat transfer tube 24. And the 1st fixing | fixed part 6 and the 2nd fixing | fixed part 7 are open | released, and the heat exchanger 2 is removed from the pipe expansion apparatus 1. FIG.

  The tube expansion process is performed by the operation as described above, and the fins 23 and the heat transfer tubes 24 are fixed.

<Characteristic>
In this pipe expanding apparatus 1, the fins 23 are densely arranged in advance by the moving member 8, and the moving member 8 moves so that the fins 23 spread as the pipe expanding process proceeds. For this reason, the downward movement of the fins 23 due to the deformation of the heat transfer tubes 24 is restricted by the moving member 8, and the fins 23 are prevented from being densely arranged at the lower end portion of the heat exchanger 2. For this reason, fin pitch can be closely approached up and down. Thereby, the abnormal noise produced at the time of ventilation can be reduced. In addition, the appearance quality of the heat exchanger is improved.

<Second Embodiment>
The following control may be performed on the movement of the mandrel 4 and the moving member 8 during the pipe expansion process.

  First, similarly to the first embodiment, the moving member 8 is moved upward to push up the fins 23 upward. The moving member 8 is temporarily fixed at a position where the fin 23 is pushed up. Next, the mandrel 4 is moved downward and inserted into the heat transfer tube 24. After the mandrel 4 is inserted into the heat transfer tube 24, the support that restricts the downward movement of the moving member 8 is released, and the pressing force in the second direction that the moving member 8 applies to the fins 23 is reduced. . Thereby, the moving member 8 naturally descends downward by the downward pressing force received by the fins 23 due to the deformation of the heat transfer tube 24. Other controls are the same as in the first embodiment.

  It is possible to make the fin pitch close to uniform also by such control.

<Third Embodiment>
The following control may be performed on the movement of the mandrel 4 and the moving member 8 during the pipe expansion process.

First, before the moving member 8 is moved upward and pushes the fins 23 upward, the mandrel 4 is moved downward and inserted into the heat transfer tube. After the mandrel 4 is inserted into the heat transfer tube 24, in the initial mandrel 4 moves through the heat transfer tube 24 in a downward direction, the moving member 8 is moved upward push the upward fin 23. Thereafter, as the mandrel 4 moves downward, the moving member 8 also moves downward. Other controls are the same as in the first embodiment.

  By performing such control, the fin pitch can be made uniform.

<Other embodiments>
(1)
In the above embodiment, the control unit 10 performs control to make the fin pitch close to uniform, but the control is not limited to making the fin pitch uniform, and control for making the fin pitch different for each part is performed. It may be broken. The control unit 10 can adjust the fin pitch distribution by adjusting the timing and speed of moving the moving member 8 upward, or the timing and speed of moving the moving member 8 downward. For example, in the first embodiment, when the moving member 8 moves downward in accordance with the lowering of the mandrel 4, the fin pitch increases when the moving member 8 moves fast, and the fin pitch decreases when the moving member 8 moves slowly. Become. Further, when the moving member 8 moves upward while the mandrel 4 is descending, the fin pitch of the upper fins 23 is reduced, resulting in a dense distribution. In this way, by adjusting the movement of the mandrel 4 and the movement of the moving member 8, the fin pitch distribution can be adjusted to a desired mode.

(2)
In the above embodiment, the moving member 8 is driven by the moving member driving unit 9 and is controlled by the control unit 10, but from the viewpoint of making the fin pitch close to uniform, the moving member 8 is manually moved. May be. The fins 23 can be pushed upward by manually moving the moving member 8 upward before the mandrel 4 is inserted into the heat transfer tube 24. Then, the moving member 8 is supported by a stopper or the like so as not to move, and the support by the stopper is released in accordance with the insertion of the mandrel 4 into the heat transfer tube 24. Thereby, the moving member 8 naturally moves downward by the downward pressing force received by the fins 23 due to the deformation of the heat transfer tube 24. As a result, the fins 23 that have been moved upward in advance are expanded downward by the tube expansion process, and the fin pitch can be made to be uniform.

(3)
Although the vertical tube expansion device 1 is shown in the above embodiment, the present invention can also be applied to a horizontal tube expansion device in which the heat transfer tubes 24 are arranged in parallel in the horizontal direction. However, in the vertical type tube expansion device, the fins 23 are likely to move downward due to the influence of gravity, so adjustment by the moving member 8 is more effective.

  The present invention has an effect that the fin pitch can be adjusted to a desired state in the tube expansion process, and is useful as a tube expansion device.

The front view of a pipe expansion apparatus. The heat exchanger which receives a pipe expansion process, and its surrounding block diagram. The bottom view of a heat exchanger and a 2nd fixing | fixed part. The enlarged view near the 2nd fixed part. The figure which shows the structure of the heat exchanger vicinity in a pipe expansion apparatus. The control block diagram of a pipe expansion apparatus. The figure which shows operation | movement of the mandrel and the moving member 8 in a pipe expansion process.

DESCRIPTION OF SYMBOLS 1 Tube expansion apparatus 2 Heat exchanger 4 Mandrel 5 Mandrel drive part 8 Moving member 9 Moving member drive part 10 Control part 23 Fin 24 Heat exchanger tube A2 Down direction (2nd direction)
A3 upward (first direction)

Claims (5)

In the heat exchanger (2) including a plurality of fins (23) provided with a plurality of holes and stacked, and a plurality of heat transfer tubes (24) inserted into the holes and penetrating the fins (23), the fins ( 23) a tube expansion device for expanding the heat transfer tube (24) inserted in the hole of 23) and fixing the fin (23) and the heat transfer tube (24),
A plurality of mandrels (4) that are inserted into the heat transfer tube (24) from one end side of the plurality of heat transfer tubes (24) to expand the heat transfer tube (24);
It is movable in a first direction (A3) from one end side to the other end side of the heat transfer tube (24) and a second direction (A2) from the other end side to the one end side of the heat transfer tube (24). A moving member (8) provided to support the fin (23);
A mandrel drive unit (5) for driving the mandrel (4);
A moving member drive unit (9) for driving the moving member (8);
A control unit (10) for controlling the mandrel driving unit (5) and the moving member driving unit (9);
Equipped with a,
The controller (10) moves the moving member (8) in the second direction (A2) before the mandrel (4) is inserted into the heat transfer tube (24) to move the fin (23 ) In the second direction (A2), and the mandrel (4) is moved in the first direction (A3) and inserted into the heat transfer tube (24), and then the moving member (8) In the first direction (A3),
Tube expansion device (1). The moving member (8) can support the fin (23) located on the most other end side of the heat transfer tube (24) among the plurality of fins (23).
The tube expansion device (1) according to claim 1. The controller (10) moves the moving member (8) in the first direction (A3) as the mandrel (4) advances in the heat transfer tube (24) in the first direction (A3). ,
The tube expansion device (1) according to claim 1 . The controller (10) moves the mandrel (4) in the first direction (A3) and inserts it in the heat transfer tube (24), and then controls the moving member drive unit (9) to Reducing the pressing force in the second direction (A2) applied to the fin (23) by the moving member (8);
The tube expansion device (1) according to claim 1 . The controller (10) moves the mandrel (4) in the first direction (A3) and inserts the mandrel (4) into the heat transfer tube (24), and then the mandrel (4) moves the heat transfer tube (24). Moving the moving member (8) in the second direction (A2) in the initial stage of proceeding in the first direction (A3) and pushing the fin (23) in the second direction (A2);
The tube expansion device (1) according to claim 1 .

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