JPS6352974B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a mechanical tube expansion device that can perform tube expansion according to various arrangement patterns with the mandrel still attached by simply replacing the pattern surface pressure plate.

A tube expansion device that mechanically expands the tube end opening of a heat exchanger tube in a cross-fin type heat exchanger by moving multiple mandrels with tube expansion jigs at the tips forward and backward at the same time is particularly useful. 1978-
It is known from Japanese Patent Application No. 9732, etc., and there are two types, vertical type and horizontal type, but the basic structure common to conventional devices of this type is a mandrel 6', as shown in Fig. 6.
6' are loosely inserted into the mandrel guide holes of the front plate 2 in which mandrel guide holes are provided in multiple rows and multiple columns, and the rear ends of the mandrels 6' and 6' are inserted into the front plate 2.
By engaging the surface pressure plates 4' arranged parallel to each other at the rear of the front plate 2, and moving the surface pressure plates 4' toward and away from the front plate 2 by the fluid pressure cylinder 10, the surface pressure plates 4' are arranged parallel to each other in multiple rows and multiple columns. held mandrel 6′,
6' can be moved forward and backward.

This tube expansion device is equipped with a number of mandrels corresponding to the maximum capacity of the largest number of rows and columns of the cross-fin type heat exchanger. If the two mandrels are moved forward and backward at the same time, there is a problem that they may come into contact with the heat exchanger to be processed and cause damage, so it is common practice to remove all mandrels other than those required from the surface pressure plate 4'.

In this case, the mandrel attachment means is a screw-in method (see Fig. 7), a hit pin method (see Fig. 8),
There are O-ring methods (see Figure 9).
Although the screw-in method is reliable in fixation, it is inconvenient that it takes time and effort to remove it.On the other hand, the hit-pin method uses spring pressure to engage the pin engagement hole and the hit-pin 21 by turning the mandrel 6'. This prevents the mandrel 6' from coming off, and it is relatively easy to remove and install, but since the mandrel 6' can be rotated by external force, accidents such as accidental removal often occur. This is not desirable.

In addition, in the O-ring method, the O-ring 22 is prevented from coming off by engaging with a ring groove provided around the mandrel 6, but like the hit pin method, it is easy to replace, but on the other hand, it is easy to come off naturally. There were flaws.

In this way, conventional tube expansion devices that attach and detach the mandrel all have their advantages and disadvantages, and they all have in common the loss of time due to the attachment and detachment of the mandrel.
Since there is a problem that leads to a decrease in processing efficiency, and it also poses an obstacle to promoting automation, there is a strong desire for improvement in this industry.

The present invention has been made to address these problems, and has a structure that eliminates the need to remove the mandrel even if the processing part arrangement pattern for pipe expansion is changed, and the pattern as an attachment with a simple structure. The purpose is to contribute to the rationalization and automation of pipe expansion processing by making it possible to increase or decrease the number of operating mandrels by simply replacing the surface pressure plate.

To this end, the present invention provides a mechanical tube expansion device of this type, in which a surface pressure plate 4 is attached to a pressure frame 11 which is held parallel to the rear of the front plate 2 and is removable.
At the same time, each rear end portion is engaged with the front plate 2.
On the other hand, for each mandrel 6, 6, which is formed by loosely inserting a mandrel into the mandrel guide hole and holding it in parallel in multiple rows and multiple columns, a large-diameter head _6A is attached to the rear end of each mandrel. On the other hand, the surface pressure plate 4 has two or more plates having the same overall external shape as the rear plate 12 attached to the front side of the pressure frame 11, and each plate has a rear plate 12 attached to the front side of the pressure frame 11. 12 and a pattern surface pressure plate 13 which is interposed between the pressure frame 11 and can be replaced and integrally joined to the rear plate 12.
Stepped holes 16, 16 for engaging with the stepped portion at the rear end to prevent each mandrel 6, 6 from slipping out on the forward side.
are provided in a multi-row, multi-column arrangement corresponding to each mandrel guide hole of the front plate 2, and the pattern surface pressure plate 13 is provided with mandrels 6, 6 that engage with all or a part of the mandrels 6, 6 corresponding to the arrangement pattern of the tube expansion part. Said stepped hole 1
The mandrel 6,
6, a patterned surface S serving as a contact surface for preventing the mandrel 6 from slipping out on the retreating side, and the part of the mandrel 6,
A window portion corresponding to a large diameter hole portion of the stepped holes 16, 16 that engages with other mandrels 6, 6 other than 6, and serving as an opening for allowing the mandrels 6, 6 to escape from the mandrels 6, 6 on the retreating side. 13 _A , and further,
Mandrels 6, 6 which receive the pressing force of the pressure actuator 10 through the pattern surface pressure plate 13.
A braking member 17 is attached to the front plate 2, which applies a braking force to overcome the own weight of the other mandrels 6, 6 by applying a braking force to the other mandrels 6, 6 other than the mandrels 6, 6, and restricts their movement in the forward direction. The mandrel does not need to be attached or detached each time, and the mandrel does not have to be attached or detached each time. This allows the intended purpose to be fully achieved.

Hereinafter, one embodiment of the present invention will be described in detail with reference to the accompanying drawings.

The tube expansion device shown in FIG. 1 is a vertical mechanical tube expansion device that processes a cross-fin type heat exchanger W, and is the installation base of the entire device, and supports the heat exchanger W vertically. A base 1 that also serves as a support part, a front plate 2, a plurality of connecting plates 3, 3, and a surface pressure plate 4.
are arranged horizontally in sequence from below, and are slidably fitted into guide shafts 5 vertically erected from the base 1.

The front plate 2 has mandrel guide holes drilled in multiple rows and multiple columns (for example, 3 rows x 20 columns), and as shown in a partially enlarged view in FIG. A cylindrical stripper 9 is vertically disposed coaxially with the guide hole.

Reference numeral 6 denotes a plurality of mandrels which are loosely inserted into the respective mandrel guide holes, and have a pipe expansion jig 7 firmly fixed to their tips, and whose rear ends are engaged with the surface pressure plate 4, so that the mandrels are vertically inserted. The mandrels 6, 6 are suspended in a multi-row, multi-column arrangement, and by bringing the surface pressure plate 4 into contact with and away from the front plate 2, the mandrels 6, 6 move forward (downward) and backward (upward) at the same time.

The shape of the intersection between the mandrels 6, 6 and the front plate 2 is shown in cross section in FIG.
A stripper 9 as described above is fitted and hung vertically in the mandrel guide hole through which the tube expansion jig 7 is loosely inserted at the tip of the tube. It is arranged so as to be in contact with the plate P and to be concentric with and surround the heat exchanger tube.

Reference numeral 8 denotes a flare jig which is loosely inserted into the shaft portion of the mandrel 6 and is slidably interposed in the stripper 9 in the axial direction of the cylinder, and connects the right cylindrical portion and the tapered cylindrical portion at the rear. The two cylindrical parts are equally divided into a plurality of parts, for example, four parts, along a cut plane in the direction of the cylinder axis, and are engaged with each other by means of a spring or the like so that the cylindrical shape is maintained.

The flare jig 8 is designed to move forward and backward in a short stroke within the stripper 9, and is located at a large diameter point (not shown) on the mandrel 6's mandrel.
When the flare jig 8 enters the right cylindrical portion due to the forward motion, it is pushed by this and the flare jig 8 moves forward, and the tapered cylindrical portion comes into contact with the end of the heat exchanger tube.

Further, when the mandrel 6 moves forward, the flare jig 8 is expanded against the spring pressure, and as a result, the end of the heat exchanger tube is expanded into a tupular shape suitable for flare connection. Expanding the tube and flaring the tube end can now be done simultaneously.

In FIG. 3, reference numeral 17 is a braking member for restricting the forward movement of the mandrel to prevent pipe expansion, and the details will be described later.

The surface pressure plate 4 is fixed to the center of a pressure frame 11 which is a rectangular frame with an elongated rectangular shape.
The surface pressure plate 4 is brought into contact with and separated from the front plate 2 integrally with the pressure frame 11 by the rod movement of a pressurizing actuator 10 mounted parallel to the guide shaft 5 .

At that time, although the detailed structure is omitted, the surface pressure plate 4
When the is lowered, the front plate 2 and the connecting plates 3, 3 are lowered all at once, the front plate 2 stops descending first, and then the lowermost connecting plate 3 comes into contact with the front plate 2 and stops descending, The connecting plates 3 stop descending sequentially from the bottom, and finally the front plate 2 and the surface pressure plate 4, which press down the upper tube plate P of the heat exchanger W at the lower end of the stripper 9, remove all the connecting plates 3. , 3, the descent will stop when it reaches the state where it is clamped.

Conversely, when the front plate 4 rises, it moves up a predetermined stroke from the lowest stop position to pull up the uppermost connecting plate 3, continues in the same state one after another, and finally pulls the front plate 2 up to the old position to return to the initial state. I'm starting to go back.

As shown in the figure, the mandrels 6, 6 have a stepped structure in which a large-diameter head 6A exists at the rear end of each rear end, and are shaped to prevent them from coming off downward relative to the surface pressure plate 4. is doing.

On the other hand, the surface pressure plate 4 is formed of two back plates 12 and a patterned surface pressure plate 13 that can be integrally joined together, and the rear plate 12 is mechanically connected to the pressure frame 11 by a support frame 14 at the bottom. The pattern surface pressure plate 13 is fixedly supported as a solid integral part, while the pattern surface pressure plate 13 is inserted into a support groove 15 (see FIG. 2) cut into the lower surface of the pressure frame 11 and opened on one side of the pressure frame 11. By inserting it from the side, it is firmly held between the rear plate 2 and the pressurizing frame 11 while attached to the upper surface of the rear plate 2.

The rear plate 12 has a stepped hole 16 that can engage with a stepped portion having a large diameter head 6A at the rear end of the mandrel 6.
are vertically penetrated in a multi-row, multi-column arrangement corresponding to each of the mandrel guide holes of the front plate 4, with the large diameter side holes being continuous on the top and the small diameter side holes being continuous on the bottom,
By inserting the mandrel 6 before the tube expansion jig 7 is attached into the stepped hole 16 from above, the hanging mandrel 6 will have its rear end stuck in the stepped hole 16 and will never fall out.

Next, the pattern surface pressure plate 13 has stepped holes 1 that engage with mandrels 6, 6 corresponding to the arrangement pattern of the tube expansion portion of the cross-fin heat exchanger W, that is, the mandrels to be operated for tube expansion, as shown in FIG.
A contact surface that traverses the openings of the large-diameter holes 6 and 16, that is, the openings on the rear surface (upper surface) of the rear plate 12, and prevents the mandrel 6 from slipping out in the backward direction. It has a pattern surface S, and this pattern surface S is as follows.
The large diameter head 6 of the mandrel 6 on the right side in Fig. 2
This corresponds to the lower surface of the surface pressure plate 13 that comes into contact with _A from above, and also the upper and lower 2 in Fig. 4 A and B.
Or, the surfaces marked with small black dots arranged in 3 rows and 5 or 6 columns on the left and right are applicable,
On the other hand, the large-diameter hole portions of the stepped holes 16, 16 that engage with the mandrels 6, 6 that are not expanded are formed parallel to each other and have a window portion 13A having a space A communicating therewith. For example, if the tube is to be expanded in an arrangement pattern of 2 rows by 5 columns, use the pattern surface pressure plate 13 shown in FIG. In this case, the pattern surface pressure plate 13 shown in FIG. By selecting a desired one of these and inserting it into the support groove 15 from the side, it is possible to prepare for tube expansion in various arrangement patterns.

This will be made clear in the explanation of the operation described below, but when preparing for tube expansion with a maximum arrangement pattern of 3 rows x 20 rows, it is necessary to prepare a parallel parallel shape with an equal external shape in which the entire surface is a solid surface without the window portion 13A. Needless to say, it can be inserted into the support groove 15.

The tube expansion device having the above-described structure further includes a braking member 17 attached to the front plate 2.

This braking member 17 applies a brake to the forward movement of the inactive mandrels 6, 6 other than the mandrels 6, 6 which are lowered by the pressing force of the pressurizing actuator 10 via the pattern surface pressure plate 13. In the illustrated example, a pair of groove rails 18, 18 are provided vertically from the lower surface of the front plate 2.
A stopper pattern face plate is inserted into the brake member 1 from the same side as the pattern face pressure plate 13.
I am using it as 7.

This stopper pattern face plate 17 has a pattern surface that is antisymmetrical to the pattern surface pressure plate 13.
S', which is paired with the corresponding pattern surface pressure plate 13, and which corresponds to the pattern surface pressure plate 13 in FIG. , the window portion 13A
This is a plate body in which a portion corresponding to the pattern is formed into a solid surface portion S' (see Fig. 5A), and a plate body corresponding to the pattern surface pressure plate 13 shown in Fig. 4B is shown in Fig. 5B. A plate with a

The braking member 17 is not limited to such a stopper pattern face plate; for example, an elastic collar C made of rubber may be fitted to each mandrel 6 as shown by the broken line in FIG. The elastic collar is fixed to the top plate of the front plate 2 and tightens around the mandrel 6 with appropriate elasticity, thereby overcoming the weight of the mandrel and holding the mandrel 6 from falling. In other words, other modifications are of course conceivable as long as they have a structure that brakes the downward (advance) movement of the mandrels 6, 6 that do not perform tube expansion, and can be attached to the front plate 2. .

Next, a series of operations for performing tube expansion processing using this device will be briefly explained.

A heat exchanger for a processed object in which a large number of fins and heat transfer tubes arranged in several rows and columns are temporarily fixed in a perpendicular manner, and tube plates P, P are fitted to both ends of each heat transfer tube and temporarily fixed. A front plate is provided in which a stopper pattern face plate 17 having a predetermined pattern surface S' is inserted into a pair of groove rails 18, 18, and a container W is placed vertically at a predetermined location on a base 1. 2 is lowered slightly to bring the strippers 9, 9 into contact with the upper tube sheet P at the periphery of the heat exchanger tube, aligning the pitches of the fins of the heat exchanger and determining the dimensions over the entire length. Then, a patterned surface pressure plate 13 that matches the arrangement pattern of the expanded tube portion of this heat exchanger is inserted into a predetermined position from the side.

Note that the means for inserting the double-sided plates 13 and 17 is such that the required plurality of plates 13 and 17 are stored in a rack, etc., and the necessary face plates 13 and 17 are pressurized by a pusher device or the like. A pair of groove rails 1 are provided in the support groove 15 of the frame 11 and below the front plate 2.
This can be easily done using an automatic attachment/detachment device that allows the attachment/detachment to be performed in the 8 or 18.

When the double-sided plates 13 and 17 have been inserted, the pressurizing actuator 10 is activated.

In this way, the pressure frame 11, the rear plate 12, and the pattern surface pressure plate 13 descend as one, and the mandrels 6, whose rear ends are engaged with the rear plate 12 also descend (advance). , only the mandrels 6, 6, which are prevented from coming off the large-diameter head 16A by the pattern surface S of the pattern surface pressure plate 13, are lowered together, and the large-diameter head 16A comes into contact with the pattern surface S. The mandrels 6, 6 that do not move tend to descend due to their own weight.

On the other hand, the stopper pattern face plate 17 horizontally installed below the front plate 2 has a space that allows passage of the mandrels 6, 6, which descend under the pressure of the fluid pressure cylinder 10. Since the pattern surface S' exists in the position corresponding to the mandrels 6, 6 that are about to descend by the spool, the mandrels 6, 6 necessary for tube expansion are allowed to freely descend, while the mandrels 6, 6 used for tube expansion are No mandrel 6,
6 is blocked from descending by the stopper pattern face plate 17, so only the necessary mandrels 6, 6 are lowered, and the tube expansion jig 7 at the tip is press-inserted into the corresponding heat exchanger tube to form a predetermined length. It is possible to perform pipe expansion treatment over a period of time.

Incidentally, when the mandrels 6, 6 move forward the most, the force of the fluid pressure cylinder 10 is applied to the flaring jig 8 as well, so that the flaring process of the ends of the heat exchanger tubes can be performed in conjunction.

When the pipe expansion is completed in this way, the fluid pressure cylinder 10
Although the tube expansion jig 7 and the flare jig 8 are moved back by retracting the stripper 9, the stripper 9 remains in contact with the upper tube plate P.
The heat exchanger W is securely fixed, and the tube expansion jig 7 at the tip of the mandrels 6, 6 can be smoothly removed from the inside of the heat exchanger tube.

The present invention has the above-described structure and function, and includes a rear plate 12 having a retaining function to prevent the mandrel 6 from slipping out on the forward side of the surface pressure plate 4 to which the rear end of the mandrel 6 is attached. The two mandrels 6 have the same overall external shape, with a patterned surface S and a window 13A that are in contact with the rear end of the mandrel 6 that operates to expand the tube and allow free movement toward the retreat side with respect to other mandrels 6. Two or more pattern surface pressure plates 1
Since the front plate 2 is provided with a braking member 17 that brakes the forward movement of the mandrels 6 other than the mandrel 6 for tube expansion, at least the pattern surface pressure plate 1
3, there is no need to attach or detach the mandrel 6 at all, and the expansion of various types of tubes with different numbers of rows and columns can be completed by simply replacing the pattern surface pressure plate 13. This reduces loss time when changing the pattern. , ease of handling and improvement of processing rate can be achieved.

In addition, since the mandrel 6, which is not allowed to expand, is automatically kept in a retracted position from the processing position, the mandrel 6 and the object to be processed are
There is no need for any damage to the equipment, and there is the advantage of improved reliability.

[Brief explanation of the drawing]

FIG. 1 is a front view showing a schematic structure of an embodiment of the device of the present invention, FIG. 2 is an enlarged view of section A in FIG. 1,
Figure 3 is an enlarged partial view of the front plate part in Figure 1;
4A and 4B are plan views of each example of a patterned surface pressure plate according to an example of the device of the present invention, FIGS. 5A and 5B are plan views of each example of a braking member, and FIG. The schematic structural front view and FIGS. 7 to 9 are explanatory cross-sectional views of various examples of mandrel attachment means in a conventional tube expansion device. 1... Base, 2... Front plate, 4... Surface pressure plate, 6
...Mandrel, 6A...Large diameter head, 7...Pipe expansion jig, 10...Fluid pressure cylinder for pressurization, 11...
Pressure frame, 12... Rear plate, 13... Pattern surface pressure plate, 13 _A ... Window section, 16... Stepped hole, 17...
Braking member, S... pattern surface.

Claims (1)

[Claims] 1 Pipe expansion jig 7 to be press-inserted into the pipe expansion part to be processed
A plurality of mandrels 6, 6 with
The mandrel guide holes are provided in multiple rows and columns perpendicular to the plate surface, and the front plate 2 is movable in parallel in a direction perpendicular to the plate surface. Each mandrel 6,
The mandrels 6,
A pressurizing actuator 10 that performs reciprocating motion in a direction parallel to the mandrels 6,
In the mechanical pipe expansion device, the mandrels 6, ₆ are movable forward and backward relative to the pipe expansion section supported and fixed on the base 1. On the other hand, the surface pressure plate 4
, the rear plate 12 attached to the front side of the pressurizing frame 11
and two or more sheets having the same overall external shape, each of which is interposed between the rear plate 12 and the pressure frame 11 so that it can be replaced and can be integrally joined with the rear plate 12. The rear plate 12 has stepped holes 16 for engaging with stepped portions at the rear ends of the mandrels 6, 6 to prevent each mandrel 6, 6 from slipping out on the forward side. , 16 are provided in a multi-row, multi-column arrangement corresponding to each mandrel guide hole of the front plate 2, and the pattern surface pressure plate 13 has a pattern corresponding to all or a part of the mandrels 6, 6 corresponding to the arrangement pattern of the tube expansion part. The matching stepped holes 16, 16
A patterned surface S serving as an abutting surface for blocking the large diameter hole portion of the mandrels 6, 6 to prevent them from coming out on the retreating side, and engaging with other mandrels 6, 6 other than the above-mentioned part of the mandrels 6, 6. The stepped hole 1
The mandrels 6, 6 are provided with window portions _13A corresponding to the large diameter holes 6, 16, which serve as openings for allowing the mandrels 6, 6 to come out on the retreating side, and The mandrels 6, 6 other than the mandrels 6, 6 that receive the pressing force of the pressurizing actuator 10 are brought into contact with the front end or circumferential surface of the mandrels 6, 6 to apply a braking force to overcome their own weight and move in the forward direction. A mechanical pipe expansion device characterized in that a braking member 17 is attached to the front plate 2 to limit the amount of water.