JPH06218468A - Tube expanding device - Google Patents

Abstract

PURPOSE:To provide a tube expanding device by which troublesome attaching and detaching operation for an expanding mandrel is eliminated and only a necessary mandrel along an expanding pattern is used and which is excellent in workability and having extremely high production efficiency. CONSTITUTION:A mandrel releasing means and a mandrel restraining means are provided on a back and forth working body 9, a heat exchanger mounting device 3 on which plural heat exchangers 17 are mounted, at least in one line, and a heat exchanger transferring device 4 by which the heat exchangers 17 mounted on the mounting device 3 are simultaneously held and simultaneously released after transferred by a specific distance and which is reversely moved to the initial position after the heat exchangers 17 are released are successively provided in the tip end direction of the mandrel 6 restrained on the back and forth working body 9.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe expanding device, and more specifically, to a continuous supply of the heat exchanger to be expanded by allowing the heat exchanger to pass through the pipe expanding device from one direction to the other direction. The present invention relates to a pipe expanding device capable of not only discharging and discharging but also shortening the set time and the take-out time of the heat exchanger, and also capable of instantaneously changing the pipe expanding pattern of the heat exchanger to be set. .

[0002]

2. Description of the Related Art Conventionally, as a pipe expanding device used for expanding a heat exchanger, for example, as shown in FIGS.
A plurality of pipe expanding mandrels (14) are suspended from a reciprocating body (13) vertically movable via a cylinder (12), and a predetermined number of heat radiating fins (16) and heat radiating fins are provided below the reciprocating body (13). A heat exchanger mounting table 19 for setting the heat exchanger 17 formed by a plurality of pipes 15 to be expanded inserted in 16 to the reciprocating motion body 13 and a hydraulic cylinder on the base 20a. There is a tube expanding device 20 rotatably provided by 18 and a predetermined rotating mechanism, and is appropriately used for the tube expanding operation of the heat exchanger.

When the heat exchanger 17 for expanding the pipe is supplied to the pipe expanding device 20 having the above-mentioned structure, the worker himself / herself has transferred the heat exchange through a carriage (not shown) or the like. The heat exchangers 17 for pipe expansion were sequentially supplied by transferring the heat exchangers 17 to the heat exchanger mounting table 19 and sequentially setting them.

[0004]

However, as in the prior art, the heat exchanger transferred by the operator himself via a carriage (not shown) or the like is sequentially transferred to the heat exchanger mounting table. In the case where the heat exchangers for expanding the pipes by setting them are sequentially supplied to the pipe expanding device, there are the following problems.

That is, in the tube expanding device using the conventional heat exchanger mounting table, after taking out the heat exchanger after tube expansion from the heat exchanger mounting table, the heat exchanger for performing the next tube expansion is reheated. It must be set on the exchanger mounting table, and the expanded heat exchanger must also be transferred to some transfer means and transferred to the next step.

Therefore, if a conveyer or the like for supplying the heat exchanger is installed up to the heat exchanger mounting table of the tube expanding device, complicated work etc. relating to the setting of the heat exchanger can be eliminated, but, Since the heat exchanger has a very unstable structure in which a pipe for expanding the pipe is inserted through a plurality of radiating fins, the pipe is removed from the radiating fin when it is placed on a conveyor or transferred. The heat exchanger before pipe expansion cannot be simply placed on a conveyor or the like and transferred, because the heat exchanger will be disassembled or the overall shape of the heat exchanger will be distorted.

Further, the tube expansion pattern of the heat exchanger mounted on the heat exchanger mounting table as described above is not only different depending on the type of the heat exchanger, but also depending on the type of the heat exchanger, at the time of tube expansion. , A pipe expanding mandrel suspended at a position facing a pipe other than the pipe expanding object inserted into the heat exchanger and a pipe expanding mandrel that may come into contact with the heat radiation fins must be removed from the reciprocating body in advance. As a result, there has been a very serious problem that the removal work is very complicated and takes time.

Therefore, there is a time loss such as the take-out time of the heat exchanger after the tube expansion, the setting time of the next tube expansion heat exchanger, and the transfer time of the heat exchanger for the transfer to the next process. Not only that, the work such as removing and installing the pipe expanding mandrel is extremely complicated and takes a lot of time, which significantly impedes the operating time of the pipe expanding device, resulting in a serious decrease in productivity and work efficiency. Was there.

However, the present invention solves all of the above problems, and always holds firmly a heat exchanger having an extremely unstable structure before and after pipe expansion, and at the same time, the heat exchanger. Since it can be continuously transferred to a predetermined location on a straight line, it takes time to take out the heat exchanger after pipe expansion, set time for the next heat exchanger for pipe expansion, and further transfer the heat exchanger to the next process. It is possible not only to eliminate the time loss such as the transfer time to the trolley for carrying out the expansion, but also to perform the expansion pipe mandrel required according to the expansion pattern of the heat exchanger without any troublesome attachment and detachment work of the expansion pipe mandrel. It is an object of the present invention to provide a tube expanding device which can be used only with excellent workability and has extremely high production efficiency.

[0010]

That is, according to the present invention, only the mandrel 6 facing the reciprocating body 9 from the reciprocating body 9 that advances toward the heat exchanger 17 and faces the pipe 15 that is not the expansion target. Is provided with a mandrel escape means for projecting the reciprocating body 9 in a direction opposite to the moving direction of the reciprocating body 9 to escape, and all the mandrels 6 are always prevented from being inserted into or removed from the reciprocating body 9. A heat exchanger that is locked to the reciprocating body 9 via locking means, and is expanded in the distal direction of the mandrel 6 via the mandrel 6.
Each of the seventeen is provided with a heat exchanger mounting base 3 capable of mounting at least one row in a direction intersecting the reciprocating direction of the reciprocating body 9, and along the longitudinal direction of the heat exchanger mounting base 3. In the vicinity of the heat exchanger mounting table 3, each of the heat exchangers 17 mounted on the heat exchanger mounting table 3 in at least one row is held at the same time, and the heat exchangers 17 are moved in one direction by a predetermined distance and are fixed. After moving the distance, the held heat exchangers 17 are simultaneously opened, and the heat exchangers 17 placed on the heat exchanger mounting table 3 are moved in the opposite direction to hold the heat exchangers 17 at the same time. The heat exchanger transfer device 4 is connected in a reciprocating manner.

[0011]

In the tube expanding device having the above-mentioned structure, the reciprocating body 9 is provided with the mandrel releasing means and the mandrel locking means, and the heat expanding the mandrel 6 through the mandrel 6 in the tip direction of the mandrel 6. Each of the exchangers 17 is provided with a heat exchanger mounting table 3 that can be mounted in at least one row in a direction intersecting the reciprocating direction of the reciprocating body 9, and in the longitudinal direction of the heat exchanger mounting table 3. In the vicinity of the heat exchanger mounting table 3 along the same side, while simultaneously holding each of the heat exchangers 17 mounted on the heat exchanger mounting table 3 in at least one row, and moving in a direction by a certain distance, Further, after moving a certain distance, each of the held heat exchangers 17 is opened at the same time, and again in the other direction to hold each of the heat exchangers 17 placed on the heat exchanger mounting table 3 at the same time. The moving heat exchanger transfer device 4 can reciprocate freely Since it is provided, the heat exchanger 17 having an unstable structure is always firmly held without causing distortion in the overall shape of the heat exchanger 17 regardless of before and after pipe expansion. The heat exchanger 17 can be automatically transferred continuously to a predetermined position on a straight line, and unnecessary pipe expansion is performed along the pipe expansion pattern of the heat exchanger without any troublesome attachment and detachment work of the pipe expansion mandrel 6. The mandrel can be escaped from the reciprocating body 9.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, reference numeral 1 denotes a stand 2 which is erected on a base 1a.
1 shows a tube expanding device composed of a book column 1b.

Reference numeral 2 is a cylinder provided for vertically moving a reciprocating body 9 on which a pipe expanding mandrel 6a is vertically installed, and two cylinders are provided above the pipe expanding device 1 so as to be vertically movable through two guide posts 7. It becomes.

Below the reciprocating body 9, a flare punch plate 5 provided with a flare punch 5a for subjecting a pipe of the heat exchanger after expansion to a predetermined flare process is provided with a predetermined suspension rod body (not shown). (3) is suspended from the reciprocating body 9.

As shown in FIG. 2, 8a is provided in each of a predetermined number of through holes 9a arranged along the reciprocating direction of the reciprocating body 9, and in each of the through holes 9a. The axial length of the mandrel 6 is located above the head 6a of the mandrel 6 in the recess 9b into which the head 6a (mandrel supporting means) having a diameter larger than that of the shaft 6b of the mandrel 6 to be inserted can be fitted. 2 shows a reciprocating body (mandrel escape means) provided so as to be able to move back and forth in a direction intersecting the direction, and a plurality of cylinders 8 arranged corresponding to each of the mandrels 6 locked by the reciprocating body 9. Mounted on the telescopic rod 8b of the
It is configured to be reciprocally movable along a guide hole 9c bored in the inside.

Reference numeral 3 denotes a heat exchanger 17 expanded by a pipe expanding mandrel 6 which is locked to the reciprocating body 9 and can be placed in a line in a direction intersecting with the reciprocating direction of the reciprocating body 9. 7 shows a heat exchanger mounting table having a different heat exchanger mounting portion 3a.

The heat exchanger mounting portion 3a intersects the longitudinal direction of the heat exchanger mounting base 3 having the heat exchanger mounting portion 3a, that is, the reciprocating direction of the reciprocating body 9. A predetermined number of rotating rollers 3b are arranged side by side so as to be able to reciprocate in a free state each of the heat exchangers 17 placed in the direction.

Numeral 4 designates an interval substantially the same as that of the heat exchangers 17 so as to simultaneously hold the heat exchangers 17 which are sequentially mounted in a row on the heat exchanger mounting table 3 and at the same time. The heat exchanger transfer device continuously provided along the longitudinal direction of the stand 3 is shown.

Each of the heat exchanger transfer devices 4 has a
A pair of rotatable heat exchanger holders 4b for holding each of the heat exchangers 17 mounted on the heat exchanger mounting portion 3a so as to face each other from both sides of the heat exchanger 17. A heat exchanger holding device 4a is provided, and the pair of heat exchanger holding devices 4a provided in the heat exchanger transfer device 4 are connected to a rotating device 10 that can rotate in forward and backward directions and have a predetermined pitch. A rod rod 10a having a male screw portion (not shown) formed therein is inserted, and the heat exchanger holding body 4b causes the heat exchanger 17 to move in both directions through forward and reverse rotations of the rod rod 10a. It is configured to be held or opened to face each other.

Reference numeral 11 denotes a large rod provided with a horizontal reciprocating movable body 11a for reciprocating the heat exchanger transfer devices 4 arranged in a row at a constant distance in the longitudinal direction of the heat exchanger mounting table 3. Indicates a cylinder.

The tube expanding device according to this embodiment has the above-mentioned structure. Next, the case of using the tube expanding device will be described.

First, as shown in FIG. 1 and FIG. 3A, the heat exchanger 17 expanded by the pipe expanding mandrel 6 locked to the reciprocating body 9 of the pipe expanding device 1 Rotating rollers arranged in parallel on the heat exchanger mounting portion 3a of the exchanger mounting base 3.
When placed on the 3b at a predetermined interval, the heat exchanger
Each of 17 is provided with a heat exchanger holder 4b provided in each heat exchanger holding device 4a of the heat exchanger transfer device 4 that is continuously provided along the longitudinal direction of the heat exchanger mounting table 3. It is pinched from both sides (arrow A) and firmly held as shown in FIG.

Next, as shown in FIG. 5C, each of the heat exchangers 17 has a heat exchanger holding device 4a of the heat exchanger transfer device 4.
The heat exchanger transfer device 4 holding the heat exchanger 17 after being firmly held via the heat exchanger holding body 4b provided in
Each of the heat exchangers 8 moves by moving with a horizontal reciprocating body 11a that moves in one longitudinal direction of the heat exchanger mounting table 3 along a predetermined guide rail 11b by a certain distance (arrow B). Is also transferred by a certain distance on the rotating roller 3b arranged in parallel on the heat exchanger mounting portion 3a.

It should be noted that each of the heat exchangers 17 transferred by the above-mentioned fixed distance is, as shown in FIG.
Through the release (arrow C) of the heat exchanger holding body 4b of the heat exchanger transfer device 4 that holds the temperature, the device is temporarily opened as shown in FIG.

Next, as shown in FIG. 4C, with the heat exchanger 17 temporarily opened, both the horizontal reciprocating body 11a and the heat exchanger transfer device 4 are connected to the guide rail 11b. Move back to the initial position again (arrow D)
By doing so, the heat exchangers 17 mounted in a row on the rotating rollers 3b arranged in parallel on the heat exchanger mounting portion 3a of the heat exchanger mounting base 3 can be simultaneously held again.

Therefore, since the heat exchangers mounted on the heat exchanger mounting table can be successively transferred while being firmly held at all times, the entire heat exchanger can be transferred before and after pipe expansion. Without distorting the shape etc., further taking out time of the heat exchanger after tube expansion, setting time of the next tube expansion heat exchanger, and further transfer time to a dolly etc. for transportation to the next process It is possible to eliminate various time losses such as, and to have highly efficient productivity and workability.

Further, the reciprocating body 9 faces the heat exchanger 17 when expanding the heat exchanger 17 sandwiched by the heat exchanger holding device 4a provided in the heat exchanger transfer device 4. Mandrel escape means is provided for causing only the mandrel 6 facing the pipe 15 not to be expanded from the reciprocating actuating body 9 that is moving forward to project and escape in the direction opposite to the moving direction of the reciprocating actuating body 9, and the mandrel is also provided. A mandrel 6 protruding in a direction opposite to the moving direction of the reciprocating body 9 via the escape means.
In addition, all of the mandrels 6 that move forward together with the reciprocating body 9 are locked to the reciprocating body 9 via mandrel locking means so that the mandrel 6 is always prevented from being inserted into and removed from the reciprocating body 9.

Therefore, even when the overall width of the heat exchanger 17 and the pipe expansion pattern are different depending on the type of the heat exchanger 17, the pipes 15 which are not expanded are inserted into the heat exchanger 17 and face each other. The mandrel 6 for expanding the pipe and the mandrel 6 for expanding the pipe that may come into contact with the radiation fins 16 of the heat exchanger 17 are not removed from the reciprocating body 9 instantaneously and simply only the predetermined mandrel for expanding the pipe. The heat exchanger can be protected by escaping from the pipes 15 and the radiation fins 16 that are not subject to expansion.

In the above-described embodiment, the tube expanding device is provided with a reciprocating body having two mandrel for pipe expanding vertically via two cylinders provided above the tube expanding device. Although it is configured to be able to move up and down, it may be a single cylinder, or four guide posts may be provided at four corners of the reciprocating body, and the reciprocating body is a pipe expanding device. It may be configured to reciprocate via an LM guide provided along a column vertically installed on the base.

Further, in the embodiment, the pipe expanding device is a so-called vertical pipe expanding device which is erected through the columns which are erected on the base. The point is that a plurality of pipe expanding mandrels are A reciprocating body provided in the exchanger, which is locked so as to be press fit into a plurality of tubes to be expanded, and a reciprocating mechanism for reciprocating the reciprocating body to expand the plurality of tubes. A horizontal tube expanding device may be used as long as it is provided, and the specific shape, mechanism, configuration, etc. of the tube expanding device are not limited at all.

Further, in the above-mentioned embodiment, the mandrel releasing means is provided in the concave portion formed in the through hole of the reciprocating body for locking the mandrel in a direction intersecting with the axial direction of the mandrel. It is composed of a reciprocating movable body that is provided so as to be able to move forward and backward at a position above the head, but it may be a reciprocating movable body that can be inserted into and removed from the mandrel in a direction intersecting the axial direction of the mandrel, Further, it is not always necessary to provide mandrel escape means corresponding to each of all the mandrels supported in the through holes of the reciprocating body,
For example, the mandrel may be limitedly provided in some through-holes in which predetermined mandrels are locked, and the mandrel escape means may be provided with a plurality of through-holes through various expansion patterns. The mandrel relief may be formed by a plate-shaped body (not shown), and the plate-shaped body (not shown) may be inserted and attached at a position above the reciprocating body so as to correspond to the pipe expanding pattern. It goes without saying that the specific mechanism, shape, mounting location, etc. of the means are by no means limited.

Further, in the above embodiment, the mandrel locking means is composed of a head portion having a diameter larger than that of the shaft portion of the mandrel inserted into the through hole of the reciprocating body. A protrusion (not shown) on the shaft of the mandrel
May be provided, and the projection (not shown) abuts on an opening peripheral portion (not shown) of the through hole of the reciprocating body, and further, the mandrel may be attached to the shaft portion of the mandrel. A groove (not shown) is formed along the axial direction of the mandrel, and a protrusion (not shown) that can be fitted into the groove formed along the axial direction of the mandrel in the through hole of the reciprocating body. No)
May be provided so that the mandrel is slidably locked, and the specific mechanism, shape, etc. of the mandrel locking means are by no means limited.

Further, in the above-mentioned embodiment, the pipe expanding device is provided with the heat exchanger mounting table having the heat exchanger mounting portion having the rotating rollers arranged side by side, in the reciprocating direction of the reciprocating body. It is possible to continuously supply a heat exchanger expanded from one side intersecting with, and is provided to sequentially discharge the heat exchanger after tube expansion to the other side, but is not necessarily limited to a rotating roller, for example, An annular belt body (not shown) may be spanned between the rotating bodies such as the rotating rollers to form a heat exchanger mounting portion, and the balls may be embedded at predetermined intervals and roll. The heat exchanger mounting portion may be formed by a body (not shown).

Further, a rail body (not shown) in which the heat exchanger mounting portion is provided along the longitudinal direction of the heat exchanger mounting base.
And a plurality of heat exchanger mounting plates (not shown) equipped with a rotating tool (not shown) that rolls along the rail body (not shown).

Further, in the above embodiment, in the vicinity of the heat exchanger mounting table along the longitudinal direction of the heat exchanger mounting table, a plurality of heats sequentially mounted on the heat exchanger mounting table are provided. A heat exchanger transfer device continuously provided at substantially the same intervals as the heat exchangers is provided to simultaneously hold each of the heat exchangers, and each heat exchanger transfer device has the heat exchanger mounting table. And a pair of heat exchanger holding devices provided with rotatable heat exchanger holding bodies for holding the heat exchanger placed on the both sides of the heat exchanger so as to face each other from both sides thereof. Each of the pair of heat exchanger holding devices is connected to a rotating device that can rotate in the normal and reverse directions, and the heat exchanger is held by the forward and reverse rotation of a rod rod having a male screw portion (not shown) of a predetermined pitch. It consists of a structure that allows the body to rotate freely, but it is not always It does not have to be a configuration for operating the exchanger holding body, and may be power of a cylinder, an electric motor, or the like. As long as it can hold each of the heat exchangers placed on the table at the same time, it may be held from the front and rear direction of the heat exchanger, and the specific shape, quantity, installation location, etc. of the heat exchanger holding body. Is by no means limited.

Further, each of the heat exchanger transfer devices is fixed in the longitudinal direction of the heat exchanger mounting table by a horizontal moving body moving via a large rodless cylinder and a predetermined interlocking mechanism (not shown). While moving by the distance of
After moving a certain distance, it is configured to move back to the initial position again. For example, each heat exchanger transfer device has a plurality of independent independent members without a horizontal moving body and a predetermined interlocking mechanism (not shown). It may be configured to be operated by a power source such as a cylinder or an electric motor, and the point is that each of the heat exchanger transfer devices simultaneously moves in one direction by a fixed distance, and again after moving by the fixed distance. The specific reciprocating mechanism of each heat exchanger transfer device is not limited as long as it is configured to move backward to the initial position in the other direction.

Further, in the above embodiment, a plurality of heat exchangers are mounted in a line on the heat exchanger mounting table, but the number of heat exchangers is not necessarily limited to one line, and there are two lines and three lines. Well,
The point is that if a plurality of heat exchangers can be mounted in at least one row at a predetermined interval, and each of the mounted heat exchangers can be simultaneously held and transported by a certain distance, the heat exchange is performed. The specific mechanism, shape, installation location, installation quantity, etc. of the equipment mounting table and the heat exchanger transfer device are by no means limited,
The design, etc. of the mechanism, shape, etc. of the members constituting the other parts can be arbitrarily changed within the scope intended by the present invention.

[0039]

As described above, according to the present invention, the reciprocating body is provided with the mandrel releasing means and the mandrel locking means.
In addition, a heat exchanger mounting table is provided in the tip direction of the mandrel so that each of the heat exchangers expanded through the mandrel can be mounted in at least one row in a direction intersecting the reciprocating direction of the reciprocating body. And in the vicinity of the heat exchanger mounting table along the longitudinal direction of the heat exchanger mounting table, simultaneously hold each of the heat exchangers mounted on the heat exchanger mounting table in at least one row. Move a certain distance in one direction,
And, after moving for a certain distance, each of the held heat exchangers is opened at the same time, and heat is moved in the other direction in the opposite direction so as to simultaneously hold each of the heat exchangers mounted on the heat exchanger mounting table. Since the exchanger transfer devices are reciprocally connected in series, a heat exchanger having an unstable structure can be used without causing distortion in the overall shape of the heat exchanger before and after pipe expansion. The heat exchanger can be always held firmly, and the heat exchanger can be automatically transferred continuously to a predetermined position on a straight line, and along with the pipe expansion pattern of the heat exchanger without any troublesome attachment / detachment work of the pipe expansion mandrel. The unnecessary pipe expanding mandrel can be escaped from the reciprocating body.

Therefore, the heat exchanger having a very unstable structure is always firmly held before and after the pipe expansion, and the heat exchanger is continuously transferred linearly to a predetermined position. Therefore, it is possible to remove the heat exchanger after pipe expansion, set time for the next heat exchanger for pipe expansion, and transfer time to a truck to transfer the heat exchanger to the next process. Not only is it possible to eliminate the problem, but it is also possible to use only the necessary pipe expanding mandrels along the pipe expanding pattern of the heat exchanger without any troublesome attachment and detachment work of the pipe expanding mandrel. The special effect of being able to provide a highly efficient tube expanding device has been achieved.

[Brief description of drawings]

FIG. 1 is a front view of a tube expanding device according to the present invention.

FIG. 2 is a sectional view of an essential part of a reciprocating body provided with mandrel releasing means and mandrel locking means in the tube expanding device of the present invention.

FIG. 3 shows a transfer state of a heat exchanger in the tube expanding device of the present invention, and (A), (B) and (C) of FIG.

FIG. 4 shows a transfer state of the heat exchanger in the tube expanding device of the present invention, and FIGS.

FIG. 5 is a perspective view of a conventional tube expanding device.

FIG. 6 is a side view showing a supply state of a heat exchanger in a conventional tube expanding device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Tube expansion device 3 ... Heat exchanger mounting base 4 ... Heat exchanger transfer device 4a ... Heat exchanger holding device 6 ... Tube expansion mandrel 9 ... Reciprocating body

Claims (3)

[Claims] 1. A pipe to be expanded, which is inserted into a heat exchanger (17).
A reciprocating body (9) having a pipe expanding mandrel (6) which can be press-fitted into the pipe (15) and reciprocating in opposition to the pipe (15).
In the pipe expanding device (1) having a reciprocating body (9), the reciprocating body (9) moves forward facing the heat exchanger (17).
Mandrel (6) facing the pipe (15) not expanded from (9)
Only mandrel escape means is provided for projecting only one of the mandrels (6) in a direction opposite to the moving direction of the reciprocating body (9) to escape, and all the mandrel (6) is always inserted from the reciprocating body (9). It is locked to the reciprocating body (9) through a mandrel locking means so as to prevent it from coming off, and is expanded in the distal direction of the mandrel (6) through the mandrel (6). Each heat exchanger (17) is provided with a heat exchanger mounting table (3) capable of mounting the heat exchangers (17) in at least one row in a direction intersecting the reciprocating direction of the reciprocating body (9), and the heat exchangers Table
In the vicinity of the heat exchanger mounting table (3) along the longitudinal direction of (3), at the same time, the heat exchangers (17) mounted in at least one row on the heat exchanger mounting table (3) are simultaneously installed. After holding and moving in one direction for a certain distance, and after moving for a certain distance, each of the held heat exchangers (17) is simultaneously opened and placed on the heat exchanger mounting table (3) again. A pipe expanding device, characterized in that a heat exchanger transfer device (4), which moves backward in the other direction so as to simultaneously hold each of the heat exchangers (17) that have been selected, is reciprocally connected. 2. The mandrel escaping means, in the through hole (9a) of the reciprocating body (9) supporting the mandrel (6), in the direction intersecting the axial direction of the mandrel (6). 2. The tube expanding device according to claim 1, which is a reciprocating body (8a) which is provided so as to be inserted into and removed from the (6) or to be able to move back and forth above the mandrel (6). 3. The mandrel locking means is a mandrel.
The tube expanding device according to claim 1 or 2, which is a projection formed on the shaft portion (6b) of (6) or a head portion (6a) having a diameter larger than that of the shaft portion (6b).