JPH0890123A - Device for expanding pipe - Google Patents

Abstract

PURPOSE: To make a pipe expanding device compact and to execute a smooth working by fitting a reciprocating means on the surface part of a press-in disk fitting a mandrel for expanding a pipe and arranging a twisting prevention means between the press-in disk and a column. CONSTITUTION: Plural pipe expanding mandrels 7 having dispersion billets 7b at one end side are fitted to the press-in disk 6 with a restraining part 7a. This press-in disk 6 is reciprocated along a guide post 4 through a hydraulic cylinder 5. In this pipe expanding device 1, rotary rollers 6f are fitted to both ends of the press-in disk 6 and can be rollable along a guide rail 1b provided in the column 2 of the device body 1a. By this constitution, the development of twist of the press-in disk 6 is perfectly prevented and the smooth reciprocation of the press-in disk 6 can be obtd. Further, at the time of fixing the one end side of expanding/shrinking rod 5a of the hydraulic cylinder 5 to the press-in disk 6, this fitting position is made on the column 2 side out of the guide post and made on a surface part 6e other than a peripheral part 6d and a penetration restraining hole 6b.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tube expanding device, and more specifically, to integrally fix a large number of heat radiation fins forming a heat exchanger and a hairpin tube inserted into each of the heat radiation fins. The present invention relates to a tube expanding device for press-fitting a tube expanding mandrel having a tube expanding billet into the hairpin tube to expand the tube.

[0002]

2. Description of the Related Art Conventionally, as a tube expanding device used for the tube expanding operation of the heat exchanger, as shown in FIG. 3 (a), a pair of columns 2 having a predetermined interval and each of the columns 2 are provided. A beam body 3 spanned for connection, a pair of guide posts 4 attached to both ends of the beam body 3 so as to be arranged in parallel with each of the columns 2, and a slidable outer member for the guide post 4. The pair of hydraulic cylinders 5 are fitted to each other, and are reciprocally movable through the expansion and contraction movements of the expansion and contraction rods 5a of the hydraulic cylinders 5 installed on the beam body 3. The expansion billet 7b is provided on one end side, and A plurality of through locking holes 6b are formed so that each of the plurality of pipe expanding mandrels 7 having the locking portion 7a on the other end side can be inserted and locked through the locking portion 7a so that the mandrel 7 can be pulled out in one direction. There is a pipe expanding device 1 equipped with the press-fitting board 6 that has been inserted, and is still the mainstream of the pipe expanding device. Be used well.

Further, in the tube expanding device 1 having the above-mentioned structure, as shown in FIG. 3B, the hairpin tube 11 inserted into a large number of heat radiating fins 12 superposed to complete the heat exchanger 10 is expanded. At this time, by inserting the pressure attachment 8 into the gap 6c provided in the press-fitting board 6, the extension of the telescopic rod 5a of the hydraulic cylinder 5 (arrow C) is performed to the hairpin tube 11 side. Press-in board 6 that moves in the direction (arrow D)
In addition to being able to perform a predetermined pipe expanding operation by the pipe expanding mandrel 7 provided in the
Is escaped by projecting to the other direction side (arrow E) through the mandrel escape hole 8a previously formed in the pressure attachment 8 and the escape hole 6a previously formed in the center of the press-fitting plate 6 respectively. It can be done.

[0004]

However, the tube expanding device having the above-mentioned conventional structure has the following problems.

That is, in the tube expanding device having the above-mentioned structure, each of the plurality of tube expanding mandrels 7 having the locking portion 7a at the other end side is inserted and locked through the locking portion 7a so that the mandrel 7 can be pulled out in one direction. In order to do so, the press-fitting board 6 in which a plurality of through locking holes 6b are drilled is installed in the pair of guide posts 4 and the pair of hydraulic cylinders 5.
It is possible to perform a predetermined pipe expanding operation by reciprocating the pipe 11 to be expanded, which is positioned in one direction of the press-fitting plate 3 via each of the above, and can perform a predetermined pipe expanding operation. , A mandrel relief hole 8a bored in a pressure attachment 8 inserted into a gap 6c provided in the press-fitting board 6 in advance, and an escape hole 6a bored in the center of the press-fitting board 6 in advance.
It is possible to escape by ejecting (arrow E) to the other direction side through each of the above.

Therefore, each of the pair of guide posts 4 and the pair of hydraulic cylinders 5 inevitably has both ends of the press-fitting plate 6 except for the central portion of the press-fitting plate 6 to which the plurality of pipe expanding mandrels are locked. Will be located on the side.

Accordingly, since the pair of guide posts 4 are located at both ends of the press-fitting plate 6, the reciprocating motion of the press-fitting plate 6 is smoothly performed. Since the hydraulic cylinder 5 and the telescopic rods 5a of the hydraulic cylinder 5 are also attached to both ends of the press-fitting board 6 and to the surface portion of the press-fitting board 6 excluding the central portion of the press-fitting board 6, the width of the press-fitting board 6, that is, the pipe expanding device. The width of 1 becomes very large, and not only putting in and out of a factory or the like in which the tube expanding device 1 is installed, but also the installation space is limited. In any case, the unused mandrel 7 at the time of expanding the tube,
In the tube expanding device configured to project to the other direction side of the press-fitting board 6 to escape, the telescopic rod 5a of the hydraulic cylinder 5 is attached to the surface portion of the press-fitting board 6 having the through locking hole 6b. Inevitably, the width of the pipe expanding device 1 must be increased, so that, for example, the press-fitting board 6 excluding the surface portion of the press-fitting board 6 in which the distal end of the telescopic rod 5a of the hydraulic cylinder 5 is provided with the through locking hole 6b. It is possible to make the width of the tube expanding device 1 extremely narrow by mounting it on the peripheral portion (not shown) and positioning the hydraulic cylinder 5 itself between the columns 2. However, the tip of the telescopic rod 5a is ,
Since the guide post 2 inserted into the press-fitting plate 6 is mounted on the peripheral portion of the press-fitting plate 6 while being displaced from the shaft center of the guide post 2, the press-fitting plate 6 is heavy depending on the type of the heat exchanger 10 for expanding the pipe. However, when the telescopic rod 5a expands and contracts, the press-fitting board 6 is twisted, which eventually damages the bearing (not shown) of the press-fitting board 6 and damages the guide posts. In some cases, a fatal problem may occur in which the accuracy such as the reciprocal dimension of the press-fitting board 6 is reduced by inducing abnormal wear or the like, and in any case, the limit depending on the type of heat exchanger for expanding the pipe is improved. I had to.

However, the present invention solves the above-mentioned problem, and in the pipe expanding device having a structure in which an unused mandrel is projected to the other direction side of the press-fitting plate to escape when the pipe is expanded, By providing the reciprocating means on the surface portion of the press-fitting board excluding the through locking hole of the mandrel of the press-fitting board or the peripheral portion of the press-fitting board, it is possible to cut down the entire width of the press-fitting board itself to the limit. Not only can the installation space be minimized as much as possible, but also during expansion work of any type of heat exchanger, the press-fitting board can be installed very smoothly without causing any twisting. It is an object of the present invention to provide an extremely excellent tube expanding device that can reciprocate.

[0009]

The present invention takes the following technical means in order to solve the above problems.

That is, according to the present invention, the expansion billet 7b is provided on one end side.
And a plurality of pipe expanding mandrels 7 each having a locking portion 7a on the other end side, and each of the pipe expanding mandrels 7 is inserted and locked through the locking portion 7a so as to be able to be pulled out in one direction. And a press-fitting board 6 in which a plurality of through locking holes 6b are formed.
A pair of guide posts 4 inserted through both ends of the press-fitting board 6
In a tube expanding device provided with a reciprocating means for reciprocating along a column and a column 2 for holding the guide post 4, an operating portion of the reciprocating means has a pair of opposing guide posts 4. It is located on the column 2 side with respect to each axial center position, and between the columns 2 and the press-fitting board 6, a twist preventing means for preventing twisting of the press-fitting board 6 during reciprocating motion is provided. is there.

Further, the reciprocating means is a hydraulic cylinder 5.
In addition, one end side of the telescopic rod 5a of the hydraulic cylinder 5 is attached to the peripheral portion 6d of the press-fitting plate 6 or the surface portion 6e of the press-fitting plate 6 excluding the through locking hole 6b to form an operating portion.

Further, the reciprocating means is composed of a ball screw which can be rotated normally and reversely, and a female screw body or a gear body which is screwed to the ball screw, and the female screw body or the gear body is provided around the press-fitting plate 6. Surface of the press-fitting board 6 excluding the portion 6d or the through locking hole 6b
It is attached to 6e and constitutes an operating part.

Further, the twist preventing means includes a rail body 1b provided along the longitudinal direction of the column 2, and a rotating body 6f provided on the press-fitting plate 6 and rolling along the rail body 1b. It is composed of

Further, the twist preventing means is composed of a rail body 1b provided along the longitudinal direction of the column 2 and a guide body provided on the press-fitting board 6 and sliding along the rail body 1b. It is in the configured point.

[0015]

In the tube expanding device having the above structure, the present invention is directed to a plurality of tube expanding mandrels 7 having tube expanding billets 7b at one end and locking portions 7a at the other end, and the tube expanding mandrels 7. A press-fitting plate 6 having a plurality of through-locking holes 6b for locking each mandrel 7 through the locking portion 7a so that the mandrel 7 can be pulled out in one direction, and the press-fitting plate 6 is inserted. Of a reciprocating means for reciprocating along a pair of guide posts 4 inserted at both ends of the column, and a column 2 for holding the guide posts 4, the operation of the reciprocating means. The parts are located on the column 2 side from the respective axial center positions of the pair of opposed guide posts 4, and between the column 2 and the press-fitting plate 6, the press-fitting plate 6 is prevented from being twisted when reciprocating. Since there is provided a twist prevention means for Not only can the overall width of the pipe expanding device be minimized by cutting with, but the depth (thickness in the front-rear direction) of the pipe expanding device with the minimum overall width can also be minimized, and the press-fitting board at the time of pipe expansion can also be minimized. It is possible to make the reciprocating motion of 6 smoother and prevent the press-fitting plate 6 from twisting.

Further, the reciprocating means is the hydraulic cylinder 5.
Further, since one end side of the telescopic rod 5a of the hydraulic cylinder 5 is attached to the peripheral portion 6d of the press-fitting plate 6 or the surface portion 6e of the press-fitting plate 6 excluding the through locking hole 6b to form an operating portion, It is possible to attach one end side of the telescopic rod 5a to the center of the board 6, and it is possible to reciprocate the press-fitting board 6 in a well-balanced manner even when the number of hydraulic cylinders 5 is reduced from two to one. In addition to the above, by reliably housing the hydraulic cylinders 5 between the columns 2 in the tube expanding apparatus 1, the overall height of the tube expanding apparatus 1 can be suppressed within the height of the column to make the apparatus compact.

Further, the reciprocating means is composed of a ball screw which can be rotated normally and reversely and a female screw body or a gear body which is screwed to the ball screw, and the female screw body or the gear body is arranged around the press-fitting plate 6. Surface of the press-fitting board 6 excluding the portion 6d or the through locking hole 6b
Since it is attached to 6e to form the operating part, not only can the overall height of the tube expanding device 1 be reliably suppressed within the height of the column, but also by rotating the ball screw via an electric motor (not shown). Since the press-fitting board 6 can be reciprocated without generating any noise or the like, not only is an oil temperature control device (not shown) for smoothly operating the hydraulic cylinder unnecessary, but also environmental It is possible to provide a tube expanding device suitable for the above.

Further, the twist preventing means includes a rail body 1b provided along the longitudinal direction of the column 2, and a rotating body 6f provided on the press-fitting plate 6 and rolling along the rail body 1b. Therefore, even when the operating portion of the reciprocating means is located closer to the column 2 than the axial center position of each of the pair of opposed guide posts 4, the reciprocating means reciprocates during pipe expansion. The press-fitting plate 6 can be received by both the guide post 4 and the rotating body 6f provided so as to face each other, and can be reciprocated without twisting.

Further, the twist preventing means is composed of a rail body 1b provided along the longitudinal direction of the column 2 and a guide body provided on the press-fitting plate 6 and sliding along the rail body 1b. Since it is configured, even if the operating portion of the reciprocating means is located on the column 2 side from the axial center position of each of the pair of facing guide posts 4, the press-fitting operation is performed to reciprocate during pipe expansion. The disc 6 can be received by both the guide post 4 and the guide body provided so as to face the guide post 4, and a more accurate and smooth reciprocating motion without twisting can be achieved.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. In the structure of the tube expanding device, description of the same parts as in the conventional example will be omitted below.

In FIG. 1, reference numeral 1 is a press-fitting that moves up and down via a pair of guide posts 4 mounted on a beam 3 provided between a pair of columns 2 standing upright with a predetermined interval. 1 shows a tube expanding device equipped with a board 6, and 1a shows a tube expanding device main body.

Reference numeral 1b denotes a pair of guide rails (rail bodies) which are positioned so as to oppose each of the columns 2 and are provided along the longitudinal direction of the column 2, and each of the guide rails 1b has a guide rail. A rotary roller (rotating body) 6f attached to the press-fitting plate 6 is rotatably locked to form a cam floor.

Reference numeral 9 denotes a press-fitting plate 6 positioned between the columns 2 and excluding a surface portion 6e of the press-fitting plate 6 in which a through locking hole 6b for locking the expanding mandrel 7 of the press-fitting plate 6 is formed. Showing a press-fitting board connecting body attached to a peripheral portion 6d of the hydraulic cylinder, and the press-fitting board connecting body 9 is provided with one hydraulic cylinder that is erected between the columns 2 and located at the center of the press-fitting board 6. 5
The distal end of the telescopic rod 5a is attached to form an operating portion, and the press-fitting board connector 9 raises the press-fitting board 6 when the telescopic rod 5a is extended (in the other direction), and further expands and contracts. Since the press-fitting plate 6 is lowered (one direction) when the rod 5a is contracted, not only the total width of the press-fitting plate 6 can be cut to the limit to minimize the total width of the pipe expanding device, but also the total width becomes the minimum. Also, the depth (thickness in the front-rear direction) of the pipe expanding device can be minimized, and the reciprocating motion of the press-fitting board 6 during pipe expanding can be controlled by the pair of guide posts 4 and the pair of guide rails 1b and the guide rails 1b. It is possible to surely prevent the twisting of the press-fitting board 6 by making it smooth by the twisting prevention means composed of the respective rotating rollers 6f locked and rolling.

Further, a telescopic rod of the hydraulic cylinder 5
Since the operating portion on one end side of 5a is attached to the press-fitting board connecting body 9 of the peripheral portion 6d of the press-fitting board 6 to form the operating portion, the center of the peripheral portion 6d of the press-fitting board 6 excluding the through locking hole 6b. Telescopic rod on the part
It becomes possible to attach one end side of 5a, and even if there is only one hydraulic cylinder 5, a well-balanced press-fitting board 6
Not only is it possible to perform the reciprocating motion of the pipe, but also by securely housing the hydraulic cylinder 5 between the columns 2 in the pipe expanding device 1, the total height of the pipe expanding device 1 is suppressed within the height of the column. It can be made compact.

In the above embodiment, the reciprocating means is
It is composed of a hydraulic cylinder, for example, a ball screw (not shown) which can be rotated forward and backward by an electric motor is used instead of the hydraulic cylinder, and a female screw body or a gear body (not shown) screwed to the ball screw. May be attached to the surface portion of the press-fitting board other than the press-fitting board connection body or the through locking hole. In this case, the total height of the tube expanding device can be surely suppressed within the height of the column. Not only that, but there is an advantage in that it is possible to provide an oil temperature control device and a pipe expanding device suitable for an environment free of noise and the like.

Further, in the above embodiment, the hydraulic cylinder is erected between the pair of columns so as to raise the press-fitting board when the telescopic rod is extended and lower the press-fitting board when the telescopic rod is contracted. However, for example, they may be provided in an inverted state between the columns, and in this case, only the entire width of the tube expanding device can be minimized.

Further, in the above-mentioned embodiment, the twist preventing means is a guide rail provided along the longitudinal direction of the column and a rotating roller provided on the press-fitting board and rolling along the rail body. Although the cam floor is formed from the above, the present invention is not limited to this, and, for example, the twist preventing means is provided along the longitudinal direction of the column and the track body provided on the press-fitting board. It may be a so-called LM guide configured by a guide body that slides along the guide body. In this case, the reciprocating press-fitting board is received by both the guide post and the guide body provided opposite to the guide post. There is an advantage that a smooth reciprocating motion with high accuracy and no twist can be achieved.

Further, in the above-mentioned embodiment, the press-fitting board is provided with the pipe expanding billet at one end side and the plurality of pipe expanding mandrels each having the locking portion at the other end side in one direction via the locking portion. A plurality of through locking holes are drilled so that it can be inserted and locked so that it can be pulled out, and when the pipe is expanded, the unused mandrel is drilled in the pressure attachment that is inserted into the gap provided in the press-fitting board in advance. The mandrel escape hole provided and the escape hole pre-drilled in the center of the press-fitting board can be projected to the other direction to escape, but it is not always necessary to expand the pipe through the pressure attachment. It is not necessary to select a mandrel for use in the press-fitting board, and for example, a shield (not shown) which can be reciprocally moved through a cylinder on the press-fitting board is provided above the locking portion of the pipe expanding mandrel, that is, a gap between the press-fitting board It may be provided in the department However, there is an advantage that each of the tube expanding mandrels can be instantly changed in correspondence with various tube expanding patterns of the heat exchanger, but the specific means for selecting the tube expanding mandrel is not limited. Needless to say.

Further, in the above-mentioned embodiment, the press-fitting board connecting body is provided on the peripheral portion of the press-fitting board, and the operating portion of the reciprocating means is attached to the press-fitting board connecting body. The reciprocating means does not necessarily have to be attached to the press-fitting board connecting body, and the operating part of the reciprocating means is directly attached to the peripheral part of the press-fitting board or to the surface part of the press-fitting board excluding the through locking hole. May be configured, in short, the reciprocating means is located on the column side from the axial center position of each of the pair of opposing guide posts,
Moreover, it may be provided between the column and the press-fitting board.

Further, in the above embodiment, the tube expanding device is
It consists of a so-called vertical expansion device with a column erected,
It is not necessarily limited to the vertical pipe expanding device, and may be a horizontal pipe expanding device in which the press-fitting board reciprocates in the horizontal direction, and other specific positions of the gap part for insertion and mounting of the pressure attachment and the press-fitting board. The shape, and the number of the pair of guide posts inserted into both ends of the press-fitting board may be two pairs of the guide posts inserted into both ends of the press-fitting board, and other specific types of the tube expanding device. Also, the design of each of the various components can be arbitrarily changed within the scope intended by the present invention.

[0031]

As described above, according to the present invention, the operating portion of the reciprocating means is located on the column side from the axial center position of each of the opposing pair of guide posts, and the column and the press-fitting board are provided. Since a twisting prevention means for preventing twisting of the press-fitting board during reciprocating motion is provided between the spaces, it is only possible to cut the full width of the press-fitting board to the limit to minimize the total width of the tube expanding device. Not only that, the depth of the pipe expanding device having the smallest overall width can be minimized, and the reciprocating motion of the press fitting plate during pipe expanding can be made smoother to prevent the press fitting plate from twisting.

Further, the reciprocating means comprises a hydraulic cylinder, and one end side of the telescopic rod of the hydraulic cylinder is attached to the peripheral portion of the press-fitting plate or the surface part of the press-fitting plate excluding the through locking hole to form an operating part. Therefore, it becomes possible to attach one end side of the telescopic rod to the central part of the press-fitting board, and to perform well-balanced reciprocating motion of the press-fitting board even when the number of hydraulic cylinders is reduced from two to one. Not only is it possible, but the hydraulic cylinder is surely housed between the columns in the pipe expanding device, so that the overall height of the pipe expanding device can be suppressed within the height of the column to make the device compact.

Further, the reciprocating means is composed of a ball screw which can be rotated normally and reversely, and a female screw body or a gear body which is screwed to the ball screw, and the female screw body or the gear body is a peripheral portion of the press-fitting plate. Alternatively, since it is attached to the surface part of the press-fitting board excluding the through locking hole to form the operating part, not only can the overall height of the tube expanding device be suppressed within the height of the column, but also the ball screw can be installed via the electric motor. By rotating it, the press-fitting board can reciprocate without generating any noise, so not only does the oil temperature control device for smooth operation of the hydraulic cylinder become unnecessary, but it is also suitable for the environment. It is possible to provide a tube expanding device.

Further, the twist preventing means is composed of a rail body provided along the longitudinal direction of the column and a rotating body provided on the press-fitting board and rolling along the rail body. Therefore, even when the operating portion of the reciprocating means is located on the column side from the axial center position of each of the facing pair of guide posts, the press-fitting board that reciprocates during pipe expansion faces the guide post. It can be reciprocated without being twisted by being received by both the rotating body provided.

Further, the twist prevention means is composed of a rail body provided along the longitudinal direction of the column and a guide body provided on the press-fitting board and sliding along the rail body. Therefore, even when the operating portion of the reciprocating means is located on the column side from the axial center position of each of the facing pair of guide posts, the press-fitting board that reciprocates during pipe expansion faces the guide post. It is possible to perform smooth reciprocating motion with high accuracy without being twisted by being received by both the guide body provided.

Therefore, when the pipe is expanded, an unused mandrel is
In a tube expanding device configured to project to the other direction side of the press-fitting board to escape, the reciprocating means of the press-fitting board is a surface part of the press-fitting board excluding the through locking hole of the mandrel of the press-fitting board or the press-fitting board. By installing it on the peripheral part of the press fitting board, it is possible to cut down the entire width of the press-fitting board itself to the limit, which means that the installation space can be minimized and the whole can be made compact. Even in the pipe expanding operation, it has a special effect that it is possible to provide an extremely excellent pipe expanding device that can reciprocate the press fitting plate extremely smoothly without causing any twist in the press fitting plate. It was

[Brief description of drawings]

FIG. 1 shows a tube expanding device according to the present invention, in which FIG. 1A is an enlarged side view of an essential part, and FIG. 1B is an enlarged front view of an essential part.

FIG. 2 is a sectional view taken along line AA of FIG. 1;

FIG. 3 shows a conventional tube expanding device, FIG. 3 (a) is an enlarged front view of an essential part showing a state before expanding the tube, and FIG. 3 (b) is an enlarged front view of an essential part showing a state at the time of tube expansion.

[Explanation of symbols]

 1 ... Pipe expanding device 1a ... Pipe expanding device main body 1b ... Rail body (guide rail) 4 ... Guide post 5 ... Hydraulic cylinder (reciprocating means) 6 ... Press-fitting board 6f ... Rotating body (rotating roller) 7 ... Pipe expanding mandrel 8 ... Pressing Attachment 10 ... Heat exchanger

Claims (5)

[Claims] 1. A plurality of tube expanding mandrels having a tube expanding billet (7b) at one end and a locking portion (7a) at the other end.
(7) and the pipe expanding mandrel (7), respectively.
A press-fitting board (6) having a plurality of through locking holes (6b) formed therein so as to be inserted and locked so that it can be pulled out in one direction via a), and the press-fitting board.
Reciprocating means for reciprocating (6) along a pair of guide posts (4) inserted at both ends of the press-fitting board (6), and a column (2) for holding the guide posts (4). In the tube expanding device provided with, the operating portion of the reciprocating means is located on the column (2) side with respect to the axial center position of each of the pair of opposing guide posts (4), and the column (2) A pipe expanding device, characterized in that a twisting prevention means is provided between the press-fitting plate (6) and the press-fitting plate (6) to prevent the press-fitting plate (6) from twisting during reciprocation. 2. The reciprocating means comprises a hydraulic cylinder (5), and the telescopic rod (5a) of the hydraulic cylinder (5).
One end side of the press-fitting plate (6) has a peripheral portion (6d) or a through locking hole (6d).
The pipe expanding device according to claim 1, wherein the pipe expanding device (6) excluding b) is attached to a surface portion (6e) of the press-fitting plate (6) to form an operating portion. 3. The reciprocating means comprises a ball screw rotatable forward and backward and a female screw body or a gear body screwed to the ball screw, and the female screw body or the gear body is the press-fitting board.
The tube expanding device according to claim 1, wherein the expanding portion is attached to the surface portion (6e) of the press-fitting board (6) excluding the peripheral portion (6d) of (6) or the through locking hole (6b). 4. The rail body (1b) provided with the twist prevention means along the longitudinal direction of the column (2), and the press-fitting board (6).
And a rotating body that is provided on the rail and rolls along the rail body (1b)
The tube expanding device according to any one of claims 1 to 3, comprising (6f). 5. The rail body (1b) provided with the twist preventing means along the longitudinal direction of the column (2), and the press-fitting board (6).
The tube expanding device according to any one of claims 1 to 3, further comprising a guide body which is provided on the rail and slides along the rail body (1b).