JPS6341662B2 - - Google Patents

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a device for expanding the inner diameter of a pipe, and a pipe expanding machine ( pipe expander).

[Conventional technology]

Heat dissipation elements such as condensers and evaporators are made by inserting a large number of aluminum fins into the straight part of a U-bent metal pipe, expanding the pipe, and fixing each fin tightly. For such an element, holes are drilled in multiple rows in multiple stages for each fin, and U-bent metal pipes are inserted into these holes, and elbows are inserted into the pipe openings, except for the pipes that serve as the inlet and outlet at both ends. A series of cooling medium passages are formed by The capacity required of the heat dissipation element changes depending on the performance of the cooling device itself, so the size of the fins, the diameter of the pipes, and the number of pipes inserted are different for each model.

Conventional pipe expanding machines set a workpiece, which is a metal pipe with fins inserted into it, in a workpiece setting device, press-fit a large number of mandrels attached to a ram into the pipe at once to expand the pipe, and then, if necessary, set the ram on the ram. Near the end of the downward stroke, flaring was performed for secondary and tertiary tube expansion, and the fins were stacked and stuck together.

[Problem that the invention seeks to solve]

Since the required capacity of the heat dissipation element changes depending on the performance of the cooling device main body, the size of the fins, the diameter of the pipes, the number of pipes inserted, etc. are different depending on the model. In such cases, conventionally, the mandrels were pulled out from both sides each time the multi-stage, multi-row pipes were changed. Because this mandrel is long, a pit was installed just before the tube expander, and the mandrel was placed in the pit and then taken out in front, which was inconvenient and required a long time to remove and replace the mandrel. Ta.

[Means for solving problems]

The present invention involves inserting and stacking a large number of aluminum fins into the straight parts of a large number of U-bent pipes, and setting the stack in a work setting device.
By forcibly inserting a mandrel with a spherical tip (bullet) larger than the hole diameter into the hole of each pipe to expand the pipe diameter, the outer diameter of the pipe and the fin hole are made to fit better, allowing heat to be dissipated from devices such as condensers and evaporators. Element productivity can be increased. Furthermore, when the fin size changes, the operation of unused mandrels on both ends is suppressed, completely eliminating the conventional work of pulling out unused mandrels. Furthermore, near the end of mandrel processing, the upper end of the pipe is expanded two or three times to enable flare processing.

The stroke of the mandrel is usually 100 to 1000 mm, and the number of mandrels is, for example, 2 rows, 14 stages, 6 rows.
There are various types, such as 14 tiers or 50 tiers in 6 rows. The above-mentioned mandrel is changed by pulling out the required number of mandrels from both sides, and this pulling out can be automatically operated by a selection pawl mechanism. Work stroke changes can also be automated, and all can be controlled by NC. In addition, the number of mandrels was increased from 100 to 80, and
When reducing the number of mandrels to 50, it is only necessary to operate the selection claw mechanism, but when reducing the number of mandrels used from 100 to 50 and then returning to 100, the knockout beam is used to temporarily remove all secondary and tertiary tube expansion mandrels. After the jig is pushed down, the selection claw mechanism is activated again to pull up the required number of mandrels.

The present invention will be specifically described below based on the drawings.

〔Example〕

The pipe expander is a U-bent metal pipe 1
A workpiece 100 in which a large number of fins 104 are stacked on a straight portion 102 of a metal pipe is supported on a setting device 3, and mandrels 10 in multiple stages and in multiple rows suspended from a ram 6 are press-fitted into each metal pipe at the same time to expand the pipe. By doing so, each fin is brought into close contact with each other in a laminated state.

However, in the present invention, in the above-mentioned apparatus, a lifting beam 7 is provided on the upper part of the ram 6 so as to be able to approach and separate it,
Hanging rods 12, 12 at both ends of the lifting beam 7
A stripper beam 13 is provided to hang a stripper beam 13 that prevents the workpiece from floating when the mandrel is pulled up after the pipe expansion is completed, and a mandrel selected from both ends of a large number of mandrels 10 is suspended from the lifting beam 7 when the ram is lowered. The drive screw 1 is equipped with a mandrel lifting selection claw mechanism 70 for maintaining the ram drive cylinder.
5 is provided with a mandrel stroke adjusting means 80. As will be described later, the second invention is characterized in that a pusher beam 11 and a jig 30 for secondary and tertiary pipe expansion are attached for flaring the opening of the metal pipe.

The overall configuration and each part will be explained in detail below.

Overall configuration Figures 1 and 2 are front and side views of this device, in which a frame 2 is erected on the top of a bed 1, and a work setting device 3 that can be raised and lowered is attached to the front of the base 1. . A pair of left and right hydraulic cylinders 4, 4 are provided at the front part of the frame 2, and a ram 6 is horizontally mounted on the upper ends of piston rods 5, 5. As shown in FIG. 3A, a lifting beam 7 is provided on the upper surface of the ram 6.
The mandrels 10 are placed on the mandrels so as to be able to move toward and away from the mandrels, and an expanded beam 8 is fixed to the lower surface to support a large number of mandrels 10 having chips or beads at the tips. The pusher beam 11 is suspended from the lower part of the ram 6 using a hanger member 9 such as a link or several hanging bolts. In addition, lifting rods 12 are vertically installed through the ram 6 from both ends of the lifting beam 7, and near the lower end thereof, both ends of the pusher beam 11 are penetrated.
Fix 3. Screw rods 14 are screwed into both ends of the pusher beam 11, and a driving screw 15 is also installed via a rack pinion.
On the other hand, several spacers 16 are inserted into each of the left and right lifting rods 12, and a guide plate 17 for maintaining the distance between adjacent mandrels and preventing buckling of each mandrel is attached to each spacer.

A mandrel stroke adjustment means 80 is incorporated between the screw rod 14 and the drive screw 15, as will be described in detail later, and a mandrel stroke adjustment means 80 is installed on the upper surface of the lifting beam 7, moving from both sides toward the center. A selection pawl mechanism 70 is mounted for retaining the mandrel 10 in the raised position.

Prior to the configuration of each part, a workpiece to be processed in the present invention (hereinafter simply referred to as a workpiece) will be explained.

As shown in FIGS. 3A and 24, the workpiece 100 consists of a number of fins 104 made of light metal thin plates (for example, aluminum thin plates) and a plurality of U-bent metal pipes (for example, copper pipes) 101. , Loosely insert the opposing straight parts 102, 102 of the metal pipe into the hole 105 drilled in the fin,
It is in a stacked state. End plates 106 and 107 are inserted above and below the fin stack, and the U-shaped bent portion 103 of the metal pipe is placed on the pedestal 63 of the work setting device 3. As shown in FIG. 2, this device 3 is supported by a rotation fulcrum 62 and can be raised and lowered by a cylinder 60 and an arm 61.
When setting, the workpiece 100 is held upright, and the mandrels 10 are press-fitted into the openings 108 of each pipe all at once to expand the pipe diameter by, for example, about 5%, and at the same time, the pipe length is reduced and the fins 104 are tightly fixed. It is something. In addition, the opening 108 of each pipe is 2 as described in FIG.
Next, flaring for joining the elbow 109 is performed by tertiary pipe expansion.

Mandrel The required number of mandrels 10 is prepared depending on the shape and size of the workpiece. If we refer to the entire device as 1st row, 2nd row, etc. from the front to the rear, and 1st row, 2nd row, etc. from the left to the right, for example, 4 rows and 50 rows have 200 wires, and 5 rows has 60 wires. There are 300 pieces in stages. The illustrated example shows a case where 180 mandrels are used in 3 rows and 60 stages. In addition, the mandrel thickness is
If the inner diameter of the pipe is slightly smaller than the workpiece, for example, 3/8 copper pipe (outer diameter 9.525 mm), an 8φ steel rod will be used. Its length is 50~75 than the maximum stroke
Leave it about mm long.

As shown in FIGS. 9 and 10, an engaging cylinder 20 is attached to the upper end of the mandrel using a pin 21. On the other hand, the mandrel tip has a pipe inner diameter of 5%.
A primary tube expansion tip or bullet 18 for expanding the tube to a certain degree is fixed using bolts 19. Further, a jig 30 for secondary and tertiary pipe expansion is loosely inserted into the pipe opening for flaring the open ends of adjacent pipes for elbow connection (FIG. 28).

Next, the engaging cylinder 20 and the second and third pipe expansion jigs 30 will be explained.

The engagement tube 20 at the upper end of the mandrel has an equal diameter portion 22
and a chamfered recess 23 provided in the middle of the equal diameter portion,
It consists of a neck portion 24 having a rectangular cross section extending above the equal diameter portion 22, and a chamfered head 25 formed at the upper end of the neck portion 24. The chamfered head 25 is chamfered at right angles to the advancing direction of a pulling claw member 76 (FIG. 18) of a selection claw mechanism 70 (described later), so that the claw member 76 engages with the jaw portion of the chamfered head 25. It's summery. This equal diameter portion 22 is connected to the lifting beam 7, as shown in FIG.
It is inserted through a through hole 27 common to the ram 6 and the expanded beam 8, and a stopper 29 is attached to the lower surface of the expanded beam 8 in the through hole to prevent it from coming off. Therefore, when the mandrel or tip needs to be replaced due to damage or wear, the stopper 29 can be released or removed to perform the replacement work.

The second and third tube expansion jigs 30 are different from the above-mentioned engaging tube 20 and are slidable in the axial direction on the outer periphery of the mandrel. This jig 30 forms upper and lower equal diameter parts 31 and 32 with a narrow diameter part 33 in the center as a border, and a key groove 3 in the generatrix direction of the upper equal diameter part 31.
4 is provided and is engaged with a key 35 on the upper surface of the pusher beam 11 to prevent rotation and to be guided so as to be slidable up and down. As shown in FIGS. 10 and 14, a notch 36 having a U-shaped cross section is formed in the upper equal diameter portion 31, leaving a keyway 34. As shown in FIGS. Also, the lower equal diameter portion 3
The lower part of the pipe opening 108 is used as a processing section 37 for performing secondary and tertiary expansion and flaring of the pipe opening 108.

In the mandrel 10, the engagement cylinder 20 at the upper end is engaged with and held by the expanding beam 8 by the first locking plate 41 as shown in FIGS. 3 and 9 on the ram upper surface 6a, and as the ram 6 descends, the pipe 10
1, the mandrel 10 is pulled up by the pulling claw member 76 due to a change in the workpiece, and the mandrel 10 is moved to the second locking plate 42.
It is engaged and held by the lifting beam 7 and excluded from the press-fitting process. In other words, the state is the same as when the required number of mandrels 10 are pulled out by changing the workpiece. These locking plates 41, 42
As shown in FIGS. 7-8 and 15-16, the cylinders 51 and 52 are movable forward and backward by piston rods 54 and 55 of cylinders 51 and 52 provided at the front and rear sides, respectively. Furthermore, the mandrel 10 is inserted into the hole 44 and 45 at the insertion position, and the large diameter portion 44 of the hole is provided.
Engagement cylinder 2 fixed to the upper part of the mandrel with a, 45a
The diameter portions 44b and 45b of the daruma holes are large enough to fit the equal diameter portion 22 of 0.
They are designed to engage with each other. As the locking plate 41 or 42 moves forward, either the small diameter portion 44b or 45b of each daruma hole engages with the chamfered recess 23 of the engagement tube, and as it retreats, the large diameter portion 44a or 45a of the daruma hole engages with the chamfered recess 23 of the engagement tube. aligns with the through hole 47 to allow vertical movement of the engagement tube 20.

Stripper beam 1 at the lower end of the lifting rod 12
3, the second and third tube expansion jig 30 supported by the pusher beam 11 as described above is inserted, and the mandrel 10 is inserted into this jig so that it can move freely in the vertical direction. There is. On the other hand, the lower part of the pusher beam 11 has a third locking plate 43 as shown in FIG. This locking plate 43 also has cylinders 53 (seventh to
8 and 17), it can be moved back and forth, and has a daruma hole 46 at the mandrel insertion point.

The jig 30 is inserted into an insertion hole 38 drilled in the pusher beam 11, and normally the upper notch 36 is inserted into the third locking plate 43 as shown in FIG.
(the 14th
(Figure) It is held by the push beam 11. However, for the mandrel 10 to be excluded from the press-fitting work, the cylinder 53 is actuated to lock the locking plate 4.
3 is pushed out to the 1 o'clock unlocked state, and after being pulled up to a predetermined height by the pulling claw member 76, the cylinder 53 is operated again to pull the locking plate 43, and the narrow diameter of the lower part is removed as shown in Fig. 8. The small diameter portion 46b of the daruma hole is engaged with the portion 33 and locked in an upwardly shifted state.

Pusher beam Pusher beam 11 is the jig 3 for secondary and tertiary pipe expansion.
This is for flaring the pipe opening by reducing the pressure.

As shown in FIGS. 7 and 8, the ram 6 is supported by a hanger member 9 hanging from the lower surface thereof.
As mentioned above, the central part of this beam 11 is
A large number of insertion holes 38 are formed into which the next tube expansion jig 30 is inserted. A locking plate 43 as described above is attached to the lower surface of the beam 11. In addition, as shown in FIG. 3A, the pusher beam 1
A small cylinder 50 is buried near both ends of the cylinder 1, its piston rod 49 is made to protrude upward, and a knockout beam 47 is attached to the end of the piston rod.
The knockout beam 47 has a pulling claw member 76
The mandrel 10 placed in the raised position is pushed down and returned to its original position. Figure 3A,
In the state shown in FIG. 4, the knockout beam 47 is in the raised position, but in the state shown in FIG. A state in which the next tube expansion jig 30 has been returned to its original position is shown.

The end of the pusher beam 11 is provided with a screw hole 91 into which a screw rod 14 constituting a mandrel stroke adjustment mechanism 80, which will be described later, is screwed.
An insertion hole 92 for the drive screw 15 is formed. As shown in FIG. 3B, the boss portion of the screw hole 91 is thicker than the pusher beam, and a projection 93 for releasing a stripper beam holding means 95, which will be described later, is formed at the lower outer end of the boss portion.

Stripper beam The stripper beam 13 is shown in FIGS. 3A and 3B.
As shown in FIGS. 20 and 20, it is fixed to the lower end of the hanging rod 12. On the surface of this beam 13, the same number of insertion holes 57 as the mandrels, that is, the same number as the second and third tube expansion jigs are bored. Further, a stripper mounting plate 58 is integrally fixed to the lower part of the beam. When pulling out the mandrel 10 after completing the primary expansion, secondary expansion, and tertiary expansion, a cylindrical stripper 59 is fitted into the hole 58a of the mounting plate 58, which is formed concentrically with the insertion hole 57, and the ram 6 is removed. The mandrel 10 is pulled up by driving. At this time, the stripper 59 presses the upper surface of the workpiece, prevents the workpiece from rising, supports the pulling reaction force of the mandrel, and facilitates the pulling operation.

At both ends of the stripper beam 13, as shown in FIG. 3B and FIGS. 20-21, end portions 65 are formed which are thicker than the beam, and the above-mentioned screw rod 14 and drive screw 15 are attached to these end portions 65 in the vertical direction. It has insertion holes 66 and 67 that can be inserted loosely, and the outer end has a slope 68 and a receiving claw 6 that come into contact with a stripper beam holding lever 96, which will be described later.
9 is formed.

Spacer and Guide Plate A plurality of spacers 16 are inserted into the lifting rod 12 so as to be vertically movable. However, in FIG. 2, eight spacers 16 are used, spaced apart vertically, but only two are shown in the enlarged view of FIG. 3A for ease of understanding. The spacers 16 are sequentially suspended from the lower part of the ram 6 via hanging members 9, and the lowest hanging member 9 is hung on the pusher beam 11. Further, a guide plate 17 having mandrel insertion holes 17a formed in a constant vertical and horizontal arrangement is removably attached to the spacer 16.
This maintains the distance between the mandrels and prevents buckling when the mandrels are press-fitted.

As the ram 6 descends, the distance between the ram and the pusher beam decreases, and accordingly, the lifting rod 12
The distance between the spacers 16 guided by the spacers 16 is reduced. Also, as the ram rises, the spacing is restored.

Selection claw mechanism This mechanism 70 selects one of the many mandrels.
Depending on the size of the workpiece, the mandrels of the rows selected from both ends are held in a suspended state and excluded from the press-fitting process,
It is installed on the lifting beam 7 as shown in FIG. 3A. The details are shown in FIGS. 7, 8, 18, and 19. A pair of front and rear frames 71 fixed along the longitudinal direction of the lifting beam 7
It is guided by a motor 72 attached to one end of the frame 71, a screw 73 directly connected to the motor 72, and a guide rail 74 formed inside the frame 71, and moves left and right by the rotation of the screw 73. It consists of a moving body 75 and a mandrel pulling claw member 76 provided on the moving body 75.

The screw 73 has left and right reverse threads with the center as a boundary, and one movable body 75 is screwed into each screw portion. However, in FIGS. 3A to 6, etc., only the right end is shown, and the screw extending to the left and the other moving body are not shown. Therefore,
Moving bodies 75, 75 at the left and right ends as shown in Figure 3A
are moved to the center at the same speed by the rotation of the screw 73, and when the screw 73 is rotated in the opposite direction, they are separated into left and right sides again and return to their original positions. The lifting claw member 76 has a yoke shape with a hook-shaped gap at the bottom so that the chamfered head 25 at the upper end of the engagement cylinder can engage with it, and a piston 78 of a cylinder 77 is fixed to the upper part of the yoke to raise and lower it. It is installed so that it can be used. The illustrated example is
Since the case where a workpiece inserted through three rows and multiple stages of pipes 101 is handled is shown, three sets of lifting claw members 76 are provided in the movable body 75 as shown in FIG. It is possible to pull up a total of six mandrels, three each.

Mandrel Stroke Adjustment Means The straight pipe length, that is, the workpiece height K, of the workpiece 100 is not uniform depending on the model, so it is necessary to adjust the mandrel stroke. For this purpose, as shown in Fig. 1 and Fig. 3B, drive screws 15 are erected on the left and right sides of the base 1, and the screw rods 14 parallel to these are attached so as to be movable up and down. The stroke is adjusted by the distance until it contacts the contact portion 81.

To explain in more detail, there is a drive shaft 82 in the base 1.
is suspended horizontally, and the rotation of the motor 83 is controlled by the worm mechanism 8.
Rotation is transmitted to the drive screw 15 via the drive screw 15 via the pinion 85 and the gear 86, and the screw rod 14 is raised and lowered via the pinion 85 and the gear 86. The drive screw 15 and the rod 14 are threaded with the same pitch, but when the drive screw 15 is rotated, the direction of elevation of the collar 90 below the stripper beam and the screw rod 14 is reversed. When the screw 15 is left-handed, the screw rod 14 is right-handed. Both members also have a keyway 88 or 89.

The drive screw 15 is screwed into a female threaded hole 95 of the collar 90, and its upper part is passed through the holes 66, 92 at each end of the stripper beam 13 and pusher beam 11, and the pinion 85 is attached by a sliding key. On the other hand, the screw rod 14 is connected to the collar 90 and the hole 9 of the stripper beam 13.
6 and 67, and is screwed into the female screw hole 91 of the pusher beam 11, and a gear 86 that meshes with the pinion 85 is attached with a sliding key. pinion 8
5 and the gear 86 are held down by a gear presser 87 extending from the pusher beam 11 side, and support the reaction force when converting the rotation of the pinion gear into the vertical movement of the screw rod 14.

In FIGS. 1 and 3A, the screw rod 14
Although the drawing shows one lifting rod 12 on each side, two lifting rods 12 and two screw rods 14 are used for each driving screw 15 on the left and right sides in the actual device, as shown in FIG. ing. Note that the upper surface of the collar 90 serves as a reference surface for stroke adjustment.

Stripper beam holding means Stripper beam holding means for temporarily locking the collar 90 and the stripper beam 13 when pulling up the mandrel 10 after the second and third expansion, and pressing the stripper 59 against the upper surface of the workpiece to prevent the workpiece from floating. 96 are provided.

As shown in FIG. 3B and FIG. and a release protrusion 93 formed at the end of the holder.

The holding lever 97 is rotatably supported on the outside of the collar 90 using a horizontal pin 98, and has a hooking pawl 99 that engages with the receiving pawl 69 on the active side, and a releasing protrusion 93 that abuts on the working side. It has a contacting tip 97a,
Further, on the short side, there is a coil spring 97b that tends to rotate the working side of the holding lever 97 toward the receiving claw 69 side.
has been reduced.

Before the mandrel is press-fitted, this holding lever 97 has its tip 97a in contact with a position past the slope 68 at the outer end of the stripper beam 13, as shown in FIGS. 3A and 3B. , receiving claw 6
9 and the hook 99 are separated by a large distance. As shown in FIGS. 4 and 5, as the ram 6 descends, the mandrel 10 enters the press-fitting process, but during this time, the slope 6
8 and the slope of the hooking pawl 99, or the releasing protrusion 93 and the lever tip 97a come into contact with each other, so that the receiving pawl 69 and the hooking pawl 99 do not engage with each other. When the press-fitting end is reached as shown in FIG. 6, the screw rod 14 is pushed down by a distance H by the abutting portion 81 on the lower surface of the ram, bringing the lower surface of the female screw hole 91 of the pusher beam 11 into close contact with the upper surface of the stripper beam 11. The locking claw 99 of the holding lever is engaged with the receiving claw 69 of the stripper beam to temporarily integrate the two.

After doing this, when ram 6 is raised,
With the stripper 59 pressed against the upper surface of the workpiece, only the mandrel 10 is raised all at once. When the pusher beam 11 is pulled up from the state shown in FIG. 6 to the state shown in FIG. 6
Disengage from 9. Further raise the ram 6 and
When the figure is reached, the stripper beam 13 and the upper surface of the collar 90 are separated, and the expanded pipe 101 can be pulled out from the mandrel 10. During this time, the stripper 59 presses the upper surface of the workpiece as described above, thereby preventing the workpiece from floating up. The ram is further raised to separate the stripper 59 from the upper surface of the workpiece as shown in FIG. 3, thereby completing the drawing process and preparing for press-fitting into the next workpiece.

〔motion〕

Next, the operation of the present invention will be explained.

First, a case will be described in which a workpiece is processed using all mandrels (for example, 3 rows and 60 stages).

As described with reference to FIG.
Attach it to the pipe and leave it still with the pipe opening facing upward as shown in Figure 1. In this case, as shown in FIGS. 3A and 3B, each dimension is determined as follows.

K...Work height L...Work final height (=K-S) M...Mandrel stroke N...Distance between the stripper and the top of the workpiece S...Work shrinkage G...Stripper height F...Movement amount of the stripper beam 13 (=N+
S) H...2. Set the tertiary tube expansion (flaring) stroke to, for example, 35 mm J...Distance between the bottom end of the stripper and the center of the mandrel tip E...The top of the screw rod 14 and the contact part 81
distance (=K-H) After setting as above, operate the main cylinder 4 to move the mandrel 10 to the metal pipe 101.
Press them all at once. In this case, each part is placed in the following state.

(a) The selection claw mechanism is OFF, and the movable body 75 is waiting at a position away from the mandrel center at both ends as shown in FIG. 3A.

(b) The first locking plate 41 is OFF (the eighth
Figure), (c) The second and third locking plates 42 and 43 are
When ON, the engaging tube 20 is integrated with the ram 6, and the second and third tube expansion jigs 30 are integrated with the pusher beam 13.

Under these conditions, the following steps are performed one after another.

Approach process (Fig. 3→Fig. 4) The mandrel tip 18 descends a distance N from the upper limit of the ram and touches the opening end of the pipe.
At the same time, the lower end of the stripper 59 comes into contact with the end plate 106 of the workpiece. During this time, the vehicle will be driven at high speed. Since the stripper beam 13 and the pusher beam 11 are separated by a distance H, the fourth
As shown in the figure, the lever tip 97a abuts against the protrusion 93, preventing rotation of the holding lever 97.

Primary pipe expansion step (Fig. 4→Fig. 5) As the ram 6 descends, the mandrels 10 that were in contact with the pipe opening are press-fitted into the pipe 101 all at once. When the mandrel tip 18 reaches a position within the pipe leaving a distance H (35 mm) from the stroke end, the workpiece 100 shrinks by 5% in the length direction, and S=O. During this time, if a pressure of 50 kg/cm ² is applied to each mandrel, and there are 3×60=180 mandrels, a pressure of 9 tons is required. Since the lower surface of the end portion 65 of the stripper beam 13 contacts the upper surface of the collar, which serves as a reference surface for the height of the workpiece, the stripper beam 13 does not descend any further. On the other hand, the top surface of the screw rod 14 touches the contact portion 81 on the lower surface of the ram (FIG. 5). Note that the second and third pipe expansion jigs 30 are locked to the third locking plate 43, and therefore serve to guide the mandrel during press-fitting.

2nd and 3rd pipe expansion process (Fig. 5 → Fig. 6) When the ram is further lowered from the state shown in Fig. 5,
The pusher beam 11 is pushed down until the abutment part 81 abuts the screw rod 14 and the stripper beam 13 via the female thread part 91 so that H=O, and the pipe opening is flared by the jig 30. (See Figure 27). Due to the final processing of the pusher beam 11, the holding lever tip 97 comes off the release protrusion 93 and rotates counterclockwise, so that the hanging claw 99 is engaged with the receiving claw 69 as shown in FIG. and the stripper beam 13 are temporarily integrated. These secondary and tertiary pipe expansion processes have a higher expansion rate than the primary pipe expansion, so for example, 200 kg/mandrel per mandrel.
cm ² , and a total of 180 mandrels requires a pressure of 36 tons. During this tube expansion process, the tip 1
8, the primary tube expansion continues, so
The total output requires a force of 45 tons, which is the 9 tons for the primary pipe expansion and the 36 tons mentioned above.

Return process After reaching the end of pipe expansion, main cylinder 4
By switching the oil passages from Fig. 6 to Fig. 5, Fig. 4,
Move to the state shown in Figure 3A and return to the original state.

As shown in FIG. 6, the stripper beam 13 is held in a fixed state by the operation of the holding lever 97, so that each stripper 59 continues to hold down the workpiece 100 at the periphery of the flared portion after pipe expansion, as described above. While holding the workpiece in this way, only the pusher beam 11 is raised by a distance H as shown in FIG. Rotate to disengage the holding lever 97. Next, when the ram 6 is raised to move from Fig. 5 to Fig. 4, the mandrel is pulled up from the expanded pipe, and the tip 1 is removed.
The shoulder of 8 contacts the lower end of the jig 30, and at the same time, the upper surface 6a of the ram is brought into close contact with the lower surface of the lifting beam 7.
By continuing to raise the ram, the state shown in FIG. 3A is returned.

In this way, each fin 10 is
4 is fixed to the straight portion 102 of the pipe, and the opening 108 is flared. After taking this out from the work setting device 3,
The pipes are then sent to another process where elbows 109 are joined between adjacent pipes as shown in FIG. 28 to form a final product.

Stroke adjustment effect If the height of the workpiece is changed, adjust the mandrel stroke as follows.

In FIGS. 3A and 3B, since the stripper height G and the second and third pipe expansion strokes H are constant, when the final workpiece height L changes, the drive motor 82 is driven and the shaft 83 worm mechanism 94
The drive screw 15 is rotated through the. By transmitting the rotation of the screw 15 to pinion gears 85, 86 and reversing the screw rod 14, the distance F between the lower surface of the stripper beam and the upper surface of the collar is changed to adjust the mandrel stroke.

When processing small workpiece heights,
For example, by rotating the drive screw 15 to the left, the third A
The collar 90 is moved downward as shown by the arrow in the figure, and the screw rod rod 14 is rotated clockwise to shorten the distance E between the top surface of the rod and the contact portion 81 by the same amount as the amount of movement of the collar. On the other hand, if the height of the workpiece is large, rotate the collar 9 in the opposite direction to the front.
0 and lowers the rod 14 to increase the distance E.

Pulling out unused mandrels When processing a condenser, evaporator, etc. without using the entire number of mandrels, pull out the required number of mandrels from both ends from inside the machine. To this end, the invention operates a selection pawl mechanism 70 mounted on the lifting beam 7.

FIG. 7 shows the mandrel 10 during the tube expansion process. For such a mandrel, as mentioned above, the first locking plate 41 is OFF,
When the second locking plate 42 is OFF, the chamfered recess 23 of the engagement tube 20 is integrated with the expanded beam 8, and is in a suspended state. In addition, the jig 30 has a cutout portion 36 that engages with the third locking plate 43 to lock the pusher beam 11.
is supported by

Now, when pulling out a predetermined mandrel, as shown in FIG. 18 and FIG. pull up. For the mandrel in this raised position,
As shown in FIG. 8, a yoke-shaped pulling claw member 7
6 into the head 25 of the engagement tube 20 in the mandrel, the cylinder 52 is operated, the second locking plate 42 is turned OFF, the chamfered recess 23 of the engagement tube is disengaged, and at the same time the cylinder 53 to lock the third locking plate 43.
Turn it off. In addition to doing this, the moving body 75
The cylinder 77 is operated to pull it up as shown in FIGS. 8 and 10.

At this time, since the lower end of the jig 30 is in contact with the shoulder of the tip 18, the jig 30 is pulled up by the same amount as the mandrel 10 is pulled up, so the engaging cylinder 20 is supported by turning on the first locking plate 41. In this case, the third locking plate 43
By turning ON, the narrow diameter part 3 of the jig 30
Fit the small diameter portion 46b of the Daruma hole into the jig 3.
0 in the raised position.

After finishing the first row in this way,
The pulling claw member 76 is lowered, the screw 73 is rotated, the moving body 75 is advanced one pitch, and the next row of mandrels is pulled up. This is repeated to pull up the unnecessary mandrels from both ends of each row, and keep them stationary at the pulled-up position.The remaining necessary mandrels are used to perform the primary tube expansion, secondary tube expansion, and tertiary tube expansion as before.

After pulling up the required number of mandrels, when increasing the number of mandrels again, turn off all locking plates 41, 42, and 43.
Next, the knockout cylinder 50 is operated to lower the knockout beam 47 toward the pusher beam 11. The mandrel jig 30, which had been pulled up, is floating as shown in FIG. 8, but is pushed down by the lowering of the knockout beam 47. Chip 1 is in contact with the jig tip due to this pressing down.
8, each mandrel is once returned to its normal position as shown in FIG. 3A, so that the selection claw mechanism 70
By operating the machine again, processing can be performed using the required number of mandrels.

〔Effect of the invention〕

As mentioned above, the present invention involves inserting and stacking a large number of aluminum fins into the straight parts of a large number of U-bent pipes, and setting each pipe hole with a spherical tip (billet) larger than the hole diameter. By forcibly press-fitting the mandrel to enlarge the pipe diameter, it is possible to improve the close contact between the pipe outer diameter and the fin holes, and increase the productivity of the heat dissipation element. Further, when the fin size of the workpiece changes, the unused mandrels on both sides can be easily pulled out.

[Brief explanation of the drawing]

Fig. 1 is a front view of the pipe expanding machine of the present invention, Fig. 2 is a side view, Fig. 3A is a sectional view of the main part, and Fig. 3B is a sectional view of the main part.
The figure is a partially enlarged view of FIG. 3A, FIGS. 4 to 6 are cross-sectional views during the same operation, FIG. 7 is an enlarged cross-sectional view of the mandrel in the locked state, and FIG. 8 is an enlarged cross-sectional view of the mandrel in the unlocked state. Fig. 9 is a cross-sectional view showing the state in Fig. 7 in a further enlarged manner, Fig. 10 is a cross-sectional view showing the state in Fig. 8 in a further enlarged scale, and Fig. 11 is a cross-sectional view taken along the - line in Fig. 10. Figure 12 is a cross-sectional view taken along line - in Figure 9, Figure 13 is a cross-sectional view taken along line - in Figure 10, and Figure 14 is a cross-sectional view taken along line - in Figure 9.
15 and 16 are plan views of the first and second locking plates, and FIG.
The figure is an enlarged side view near the third locking plate.
18 and 19 are an enlarged sectional view and a plan view of the selection claw mechanism, FIG. 20 is an enlarged side view of the holding lever attachment part, FIG. 21 is a plan view, and FIG.
The figure is an enlarged sectional view of the mandrel tip, Fig. 23 is an enlarged plan view of the workpiece, Fig. 24 is also an enlarged side view, Figs. 25 to 27 are sectional views showing the pipe expansion process, and Fig. 28 is an adjacent pipe. It is a sectional view of a state in which a U-shaped elbow is brazed to the upper end. 1... Bed, 2... Frame, 3... Work setting device, 4... Hydraulic cylinder, 5... Piston rod, 6... Ram, 7... Lifting beam, 8... Expanding beam, 9... Hanger member, 10... Mandrel, 11... Pusher beam , 12... Lifting rod, 13... Stripper beam, 14... Screw rod, 15... Drive screw, 16... Spacer, 18... Chip, 20... Engagement tube, 23... Chamfered recess, 24... Neck portion, 25... Chamfered head ,
30...2, tertiary tube expansion jig, 41, 42, 43...
Locking plate, 44, 45, 46... Daruma hole, 47... Knockout beam, 51, 52, 5
3... Cylinder, 59... Stripper, 70... Selection claw mechanism, 75... Moving body, 76... Pulling claw member, 8
0... Mandrel stroke adjustment means, 81... Hitting portion, 84... Worm mechanism, 85... Pinion, 86
...gear, 90...collar, 91,94...female screw hole,
93... Release protrusion, 96... Stripper beam holding means, 97... Holding lever, 99... Hook claw.

Claims (1)

[Claims] 1. A workpiece in which a large number of fins are stacked on a straight portion of a U-bent metal pipe is supported on a setting device 3, and a multi-stage, multi-row mandrel 10 suspended from a ram 6 is attached to each metal pipe. This is a pipe expanding machine that press-fits the fins all at once to expand their diameter so that each fin is brought into close contact with the fins in a stacked state. A stripper beam 1 is suspended via a hanging rod 12 and prevents the workpiece from floating when the mandrel is pulled up after pipe expansion.
3; A mandrel lifting selection claw mechanism provided on the lifting beam 7 in order to keep the mandrel selected from both ends of the large number of mandrels 10 in a lifted state when the ram is lowered; and; A mandrel lifting selection claw mechanism provided on the lifting beam 7; A pipe expanding machine comprising: a screw rod 14 that can be raised and lowered; and a mandrel stroke adjusting means 80 using a contact part 81 provided on the lower surface of the ram 6. 2 A workpiece in which a large number of fins are stacked on the straight part of a U-bent metal pipe is supported on the setting device 3, and a multi-stage, multi-row mandrel 10 suspended from a ram 6 is press-fitted into each metal pipe at the same time. This is a pipe expanding machine that brings each fin into close contact in a laminated state by expanding the diameter of the fin; a lifting beam 7 placed on the upper part of a ram 6 so as to be able to move toward and away; and the top end of the hanging rods 12 on both sides of the lifted beam 7. A stripper beam 13 is suspended from the lower end and prevents the workpiece from floating when the mandrel is pulled up after pipe expansion; A lifting beam 7 is used to keep a mandrel selected from both ends of the mandrels 10 in a lifted state when the ram descends. a mandrel lifting selection claw mechanism 70 provided in; an expanded beam 8 fixed to the lower part of the ram 6;
and; a lifting beam 7 and an expanding beam 8 for detachably holding the upper part of each mandrel 10;
The first and second locking plates 4 attached to
1, 42; and a pusher beam 11 mounted on the stripper beam 13 so as to be able to approach and separate; and the pusher beam 1 for flaring the opening of the pipe near the end of the downward stroke of the ram 6.
2. A third locking plate 43 attached to the lower part of the pusher beam 11 in order to attach the 2nd and tertiary pipe expansion jig to the pusher beam 11 so that it can be detached from the pusher beam 11.
several spacers 16 supported by a hanger member 9 such as a link or several hanging bolts between the ram 6 and the pusher beam 11 and guided by left and right hanging rods 12; a ram driving cylinder; Pipe expansion consisting of a screw rod 14 that stands in parallel and can be raised and lowered, a mandrel stroke adjustment means 80 using a contact part 81 provided on the lower surface of the ram 6; and a knockout beam 47 arranged on the upper surface of the pusher beam 11. Machine. 3. The pipe according to claim 1 or 2, wherein the hanging rod 12 has a length that passes through the ram 6 and the pusher beam 11 from both left and right ends of the lifting beam 7 and reaches the stripper beam 13 at the lowest end. Tube expander. 4 The selection claw mechanism 70 includes a pair of front and rear frames 71 fixed along the longitudinal direction of the lifting beam 7;
A movable body 75 that is guided by a motor 72 attached to one end of the frame, a screw 73 directly connected to the motor 72, and a guide rail 74 formed inside the frame 71, and moves left and right by the rotation of the screw 73.
and a mandrel pulling claw member 76 provided on the movable body 75. 5 The locking plates 41, 42, 43 engage and lock the large number of corrugated holes and the narrow diameter portions of the corrugated holes by engaging with the upper part of the mandrel or the narrow diameter portion or notch portion of the jig for secondary and tertiary pipe expansion. cylinder 5 for
1, 52, and 53. The pipe expander according to claim 2, comprising: