JPH08155850A - Pipe jointing tool - Google Patents

Abstract

PURPOSE: To develop a tool usable for both jointing and separating pipes and in particular heighten pipe jointing force (enlarge packing compressing quantity). CONSTITUTION: Two pipe holding bodies 4 that can be clingingly held to a pipe by chains 15 are provided in the mutually approaching/separating state by two feed mechanism parts 5 provided in correspondence with two bar frames 3. Each pipe holding body 4 is provided with a radial pressing means 6 for bringing a pipe contact body 40 into contact with the pipe by screw feeding structure in order to further heighten holding force to the pipe.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tool used for joining pipes to each other.

[0002]

2. Description of the Related Art In a pipe adapted to be joined by a male / female fitting relationship, either the inner peripheral surface of the female pipe end or the outer peripheral surface of the male pipe end is used. On the other hand, a ring-shaped packing for preventing water leakage is fitted, and the pipes are joined to each other while the packing is compressed and deformed between the inner and outer peripheral surfaces of both male and female pipe ends. .

Therefore, since a considerably strong force is required for the joining work, a tool for facilitating this has been conventionally developed (see Japanese Utility Model Laid-Open No. 4-130174, etc.). This type of tool has a structure in which one pipe is held stationary while the other pipe is drawn toward the holding pipe by using a lever.

[0004]

In the conventional tools, when a large pipe (cast iron pipe or the like) or a pipe having a hard packing is joined in terms of size or weight, or the compression deformation amount of the packing is increased. In the case of performing the above joining, there is a case where the holding force for the pipe is insufficient (that is, slipping), and it is difficult to obtain a predetermined joining state.

The present invention has been made in view of the above circumstances, and provides a pipe joining tool capable of exhibiting a proper holding state by strongly exerting a holding force for a pipe even under various conditions. The purpose is to provide.

[0006]

In order to achieve the above object, the present invention takes the following technical means. That is, in the present invention according to claim 1, the rod frame, the first and second pipe holding bodies provided along the rod frame, and the first and second pipe holding bodies provided on one of the pipe holding bodies. And a pipe mechanism capable of abutting the held pipe on the first and / or second pipe holding bodies. It is characterized in that a radial direction pressing means having a contact body and an advancing and retracting mechanism for advancing and retracting the pipe contact body in the radial direction of the pipe is provided.

Therefore, if the pipes are to be joined to each other, the first and second pipe holding bodies are preliminarily separated from each other along the rod frame to hold the respective pipes by hugging them, and then the feed mechanism. By manipulating the parts, the two pipe holders are brought close to each other, which enables pipe joining. Further, it is also possible to separate the pipes that are already in the joined state by performing an operation reverse to the above (the feed mechanism portion is also fed in the reverse direction).

In these cases, since the first and / or second pipe holders are provided with the radial pressing means, the pipe holding force is strong and reliable, and the pipe size and weight are large. Even when joining a large-sized pipe or a pipe having a hard packing, or when joining with a large amount of compressive deformation of the packing, desired pipe joining is possible.

In the radial pressing means, a screw feeding structure can be used for the advancing / retreating mechanism (claim 2). With such a structure, there is an advantage that the pipe pressing by the radial pressing means can be reliably performed and the desired pressure can be set. This is excellent in that the pipe can be pressed under the same conditions even when the pipe diameters are different. In addition, since the structure can be simple and small, there is an advantage that an increase in manufacturing cost can be suppressed.

The first and / or second pipe holding body is a main body which can come into contact with the outer peripheral surface of the pipe at at least two points, and a main body from one end of the main body through the outer peripheral surface of the pipe. It is possible to have a configuration including a flexible diaphragm body that is stretched over the other end of the portion, and diaphragm means that can adjust the effective span of the flexible diaphragm body with respect to the main body portion. ). In this case, it is preferable to use a chain for the flexible diaphragm (claim 4).

With such a structure, the flexible throttle body (chain) has a high flexibility, and there is an advantage that the winding state around the pipe can be ensured even when the pipe diameters are various, and at the same time, There are various advantages that the structure can be made light and strong, and that it is possible to prevent an increase in size and an increase in manufacturing cost. Further, even if the pipe is clamped considerably strongly by the radial direction pressing means, it is effectively prevented that the pipe holding body is deformed by the tension of the flexible throttle body, and the pipe holding body is deformed. The decrease in the clamping force is prevented, and even if the rigidity of the pipe holding body is designed to be comparatively small, a sufficient clamping force for practical use can be obtained and the pipe holding body is prevented from being damaged.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. 1 to 8 show a first embodiment of a welding tool 1 according to the present invention, which is capable of joining pipes to each other and separating already joined pipes from each other. Is also possible.

As shown in FIG. 2, the tool 1 includes a first pipe holding body 2, two rod frames 3 fixed to the first pipe holding body 2 which are parallel to each other, and these rod frames 3. A second pipe holding body 4 slidably held on the second pipe holding body, two feed mechanism portions 5 provided for the rod frames 3 corresponding to the second pipe holding body 4, respectively. Two radial pressing means 6 provided on the second pipe holder 4
And have.

Reference numeral 8 is a guide bar, which is a double bar frame 3.
Are installed in parallel at their evenly spaced positions,
One end thereof is fixed to the first pipe holding body 2. Further, it penetrates the second pipe holding body 4 without hindering its sliding, and guides the second pipe holding body 4 to slide along the rod frame 3. The first pipe holding body 2 and the second pipe holding body 4 are substantially the same except for the presence / absence of fixing to the bar frame 3 and the guide bar 8, the presence / absence of the feed mechanism section 5, and the presence / absence of the radial direction pressing means 6. Since it is structured, the second pipe holding body 4 will be mainly described below.

The second pipe holder 4 is a rod frame 3
Leg part 1 which is bifurcated on a plane orthogonal to the longitudinal direction of
A main body 12 having 0 and 11 and a flexible throttle body 15 made of a chain or the like connected to one leg 10 of the main body 12 via a throttle means 14 (FIG. 1).
reference). That is, the first and second pipe holding bodies 2 and 4 are
Mainly composed of left and right leg portions 10 and 11 integrally formed in a substantially V-shape, the tops of the holding bodies 2 and 4 (the left and right leg portions 10,
A guide bar 8 is erected on the connection portion 11) and the pipes are configured to be held in contact with the middle portions of the left and right leg portions 10 and 11. Then, the flexible throttle body 1 which holds the pipe and clamps the pipe to the left and right leg portions 10 and 11.
5 (chain) is provided with adjustable length.

As shown in FIG. 3, the throttle means 14 includes a handle 16, a nut member 17 that holds the handle 16 so that the handle 16 can swing, and a flexible throttle body 15 that is screwed into the nut member 17 and has one end. And a connecting cylinder 19 that connects the nut member 17 to the leg portion 10 of the main body portion 12 so as to be rotatable and non-separable. A bearing 20 such as a bare link is inserted in the connecting portion of the connecting cylinder 19 with the nut member 17 so that relative rotation with the nut member 17 can be performed easily. Reference numeral 21 denotes a retaining member for the nut member 17 having a ring shape. Also,
The bulging end portion 19a of the connecting cylinder 19 is forcibly fitted into the bored ball seat portion 10a formed in the main body portion 12 (leg portion 10).

As a result, the handle 16 (nut member 17) can be easily rotated, and the hanging bolt 18 can be tilted to some extent by operating the handle to allow the hanging bolt 18 and the nut member 17 to be rotated. Is the main body 1
2 (leg part 10) is not supposed to cause abnormal wear. Therefore, by rotating the nut member 17 with the handle 16, the effective length of the flexible throttle body 15 can be changed via the suspension bolt 18.

In addition, at the projecting end of the other leg 11, as shown in FIG.
As shown in FIG. 5, a hook portion 22 is provided which can be engaged with and disengaged from a proper position on the free end side of the flexible throttle body 15. That is, near the free end of the flexible throttle body 15, connecting pins 15b for connecting the links 15a to each other project toward both sides of the link 15a.
It has a split groove 22a into which 5a is inserted, and a receiving groove 22b which is provided so as to intersect with the split groove 22a and which can be engaged with the protruding portion of the connecting pin 15b.

Therefore, the receiving groove 22b of the connecting pin 15b is formed.
It is possible to hold pipes of different sizes by changing what is engaged (see FIG. 1). In some cases, it is also possible to hold a portion of the pipe having a different diameter (a portion of which the diameter is increased, such as the female side pipe end portion of the pipe P1 as shown in FIG. 8). As shown in FIGS. 1 and 2, a pressing pad 23 made of an elastic material such as rubber or a soft material such as brass or resin is provided on the inner surface of each leg portion 10 and 11, and the pressing pad 23 is provided to the outer peripheral surface of the pipe. It is possible to make contact at points. Therefore, the surface of the pipe is prevented from being scratched while preventing slippage (slip or axial movement) with respect to the pipe.

The pressing pad 23 is held in a variable angle state through a bracket 24 having a U-shape as shown in FIG. Therefore, even when holding pipes of different sizes, the abutting state is ensured. The rod frame 3 includes the first pipe holder 2 and the second pipe holder 2.
It is arranged near the projecting ends of the leg portions 10 and 11 of the pipe holding body 4, and it is possible to reach the diameter corresponding portion of the portion holding the pipe (the inside of the ring formed by the main body portion 12 and the flexible throttle body 15). Are close to each other. That is, the rod frames 3 are positioned as far apart as possible from each other in the main body 12 whose shape is invariable. Therefore, the movement of the second pipe holding body 4 can be performed smoothly and stably.

As shown in FIG. 2, the feed mechanism 5 has rack teeth 25 provided on the upper surface of the rod frame 3 along the longitudinal direction thereof, a ratchet wheel 26 meshing with the rack teeth 25, and the ratchet wheel. Operation lever 27 for transmitting rotational drive to 26 and ratchet wheel 26
And reverse rotation preventing claws 28 and 29 provided on both front and rear sides thereof. These reverse rotation preventing pawls 28 and 29 are provided on the switching lever 3
Either one is selected by the switching operation of 2, and the ratchet wheel 26 has a structure that allows only one rotation.

Operation lever 27 and ratchet wheel 26
Are connected via a torque limiter (not shown), and idling occurs when a torque exceeding a set value is generated between them. Therefore, the operating lever 2
When the rocking operation of 7 is performed, the ratchet wheel 26 engages with the reverse rotation preventing pawl 28 or 29 to rotate in one direction, and
The pipe holder 4 moves along the rod frame 3 to move closer to or away from the first pipe holder 2.

The operating levers 27 of the respective feeding mechanism portions 5 are connected to each other and are constructed as an operating handle 35 having a generally U-shape. Therefore, both feed mechanism parts 5 can operate in synchronization with each other. This operation handle 3
No. 5 has a width dimension that can be grasped and operated by both hands, has good operability, and is easy to apply force. In addition, in the first embodiment, the first
A spring 36 capable of urging the pipe holding body 2 and the second pipe holding body 4 in mutually separate directions is fitted. Therefore, the closer the two pipe-holding bodies 2 and 4 are to each other, the stronger the urging force of the two pipe-holding bodies 2 and 4 is. However, the spring 36 is not essential, and may be fitted to the guide bar 8. Further, it is possible to cover the spring 36 with a bellows cover or the like.

The above two radial pressing means 6 are shown in FIG.
As shown in FIG. 2, the legs 10 and 11 of the main body 12 of the second pipe holding body 4 are provided so as to face each other at their projecting ends. This radial pressing means 6
As shown in FIGS. 5 and 6, has a pipe contact body 40 and an advancing / retreating mechanism 41 for advancing / retreating the pipe contact body 40 in the radial direction of the pipe.

The pipe abutting body 40 has a U-shaped metal substrate portion 43 and a cushioning material 44 such as rubber attached to the substrate portion 43. The base plate portion 43 has a mountain-folded shape in the center of the plate surface in order to increase its rigidity, and the cushioning member 44 is formed with an arcuate recess for stable contact with the pipe. The cushioning material 44 can be formed of a soft metal material such as brass or a resin material. It is also possible to integrally form the substrate portion 43 and the cushioning material 44 with a soft metal material or a resin material. Further, in the case where the pipe is a cast iron pipe or the like, it is possible to omit the cushioning material 44 by directly forming a notch on the substrate portion 43 or the like.

The advancing / retreating mechanism 41 includes a slide block 46 that holds the pipe abutting body 40 so that it can swing around a pivot axis Y parallel to the axial direction of the pipe, and the slide block 46 in the pipe radial direction (FIG. 5). It has a bracket 47 that is movably held along the left and right directions, and a propulsion shaft 48 and a support shaft 49 that are used for assembling the brackets 47 and that are used to drive and move the slide block 46.

The slide block 46 is in the shape of a square rod, and has a notch 52 formed so as to open the end portion and both side surfaces on the side opposite to the pipe contacting body 40 side. Further, an insertion hole 53 for the propulsion shaft 48 is formed from the inner side of the notch 52 toward the pipe contact body 40 side, and a screw which communicates with the insertion hole 53 and penetrates to both side surfaces. Hole 5
4 are formed.

The bracket 47 is a slide block 46.
A pair of support pieces 55 protruding in a U-shape so as to sandwich the two, and both leg portions 10 and 1 of the second pipe holding body 4 protruding upward.
1 and a mounting piece 56 that is screwed. A shaft insertion hole 57 for the support shaft 49 is formed in each of the support pieces 55. In addition, the attachment piece 56 is formed with a notch 56a that is open upward to allow the rod frame 3 to escape (see FIG. 1).

The support shaft 49 is formed to have a diameter that fits within the notch 52 of the slide block 46.
It is freely movable in the longitudinal direction. Further, with respect to the bracket 47, the flange end portion 49a and the shaft retaining ring 58 engage with the support piece 55 (opening edge portion of the shaft insertion hole 57) so as not to be detachable and rotatably held. A screw hole 59 is formed in the support shaft 49 at a position where the support shaft 49 crosses the cutout 52.

The propulsion shaft 48 has a constricted portion 62 formed at the tip of a bolt material and a hexagonal head 63 formed at the other end, and is screwed through a screw hole 59 of a support shaft 49. In this state, the constricted portion 62 at the tip end portion is inserted into the insertion hole 53 of the slide block 46. In this propulsion shaft 48, the retaining bolt 65 having the engaging tip pin 64 has the screw hole 5 of the slide block 46.
By being screwed into the slide block 46, the slide block 46 is held in a rotatable state and a retaining state.

Therefore, in this advancing / retreating mechanism 41, the propulsion shaft 48
Rotation of the propeller shaft 48 relative to the bracket 47.
At the same time, the slide block 46 itself is moved back and forth, whereby the pipe contact body 40 can be brought into contact with the pipe or separated from it. The pipe abutting body 40 is swingable with respect to the slide block 46, and the slide block 46 is rotatable with respect to the bracket 47 around the support shaft 49. The contact with the pipe by 44 is ensured (it becomes easier to follow the pipe radial direction).

With the tool 1 having such a configuration, as shown in FIG.
As shown in (a), in order to join the pipe P1 (the female side pipe end is the side facing) and P2 (the male side pipe end is the side facing), first, the rod frame 3 is attached. On the other hand, the second pipe holding body 4 is moved to a position separated from the first pipe holding body 2. The tip of the pipe P2 is the pipe P1.
Insert it so that it abuts the inner ring-shaped packing D.

Next, for both pipes P1 and P2,
While the second pipe holding bodies 2 and 4 are made to correspond to appropriate positions (for the pipe P2, it is necessary to consider a predetermined joining margin from the pipe end), and each flexible throttle body 1
5 is wound around each of the pipes P1 and P2, and their free end positions are engaged with the hook portions 22 (see FIG. 4).
Then, the squeezing means 14 is operated to apply tension to the flexible squeeze member 15 to firmly tighten it around the pipe.

Next, the propelling shaft 48 is rotated in the radial direction pressing means 6 on both sides of the second pipe holding body 4 to move the pipe P2.
The pipe contacting body 40 is brought into contact with. As the degree of contact of the pipe abutting body 40 with the pipe P2 is increased, both legs 10 and 11 of the body portion 12 of the second pipe holding body 4 are to be deformed in the leg opening direction. Although a reaction force will be generated, the two leg portions 10 and 11 are connected to the pipe P.
Since the flexible diaphragm body 15 is connected to the leg portions 10 and 11 by the reaction force,
It does not actually happen that the legs are deformed. That is, the holding force of the second pipe holding body 4 with respect to the pipe P2 is generated to be that strong and reliable.

After these preparations are completed, the feeding mechanism 5
The second pipe holding body 4 is moved to the first position by operating the switching lever 32 of
Set so that it faces the pipe holder 3, and operate the handle 3
Swing 5 Thereby, the pipes P1 and P2 can be reliably joined. In this case, the second pipe holding body 4 is held by the two rod frames 3 and the propulsive force is synchronously obtained from the two feeding mechanism portions 5 provided corresponding to the rod frames 3. Therefore, the second pipe holding body 4 is prevented from being twisted with respect to the rod frame 3 in advance, and the movement thereof can be performed smoothly and reliably.

Of course, since the operation levers 27 of the respective feed mechanism parts 5 are connected by the common operation handle 35, the synchronization is not lost, and the pipes P1 and P2 themselves are twisted. In addition, the operating force of the operating handle 35 does not become extremely heavy. Further, since the operation handle 35 can be operated with both hands, there is an advantage that operability is good and force is easily applied.

On the other hand, as shown in FIG. 8 (b), in order to separate the pipes P1 and P2 which are already joined to each other, first, the second pipe holder 4 is held on the rod frame 3 by the first pipe holder. It is moved to a position close to the body 2. Then, the holding bodies 2 and 4 are set at appropriate positions of the pipes P1 and P2 in the same manner as described above, and the switching lever 32 of the feed mechanism unit 5 is set.
To the side opposite to the above. When the operation handle 35 is rocked in this state, the second pipe holding body 4 is separated from the first pipe holding body 2 and the pipes P1, P
The two can be separated. Even during this separating operation, the second pipe holding body 4 is smoothly and reliably moved, so that local stress can be prevented from being generated in the pipe and the separated pipe is not damaged.

The present invention is not limited to the above embodiments. For example, as the flexible throttle body 15, a wire rope or the like can be used instead of the chain. In this case, the diaphragm means 14 may be replaced with an appropriate mechanism such as a winch. When a chain is used as the flexible throttle body 15, in order to further enhance the action of blocking the reaction force against the contact of the radial direction pressing means 6, the link 15a is made thicker and the link assembly width is increased, and the material of the link is hard. It suffices to take measures such as increasing the number of links 15a in the width direction (having three or more rows), and increasing the number of flexible diaphragm bodies 15 themselves (having two or more).

Although not shown, the flexible diaphragm body 15
An elastic coating material such as rubber or soft resin may be provided at a portion of the pipe that comes into contact with the pipe so that the pipe can be brought into contact with the pipe stably (closely) without slipping. Furthermore,
Flexible diaphragm body 15 as the first and second pipe holders 2 and 4.
It is also possible to adopt a configuration that does not use. For example, although not shown, as a structure (for example, a handcuff-like structure) in which an arcuate link is swingably connected to one leg 10 or 11 and can be connected to and separated from the other leg It is possible to set. In this case, a pressing claw for pressing the outer peripheral surface of the pipe may be provided on the inner surfaces of the leg portions 10 and 11, the inner surface of the arcuate link, and the like so as to be movable in and out by a bolt.

The number of rod frames 3 and guide bars 8 used is not limited. For example, as shown in FIG. 9 as a second embodiment of the pipe joining tool 1, a first pipe holder 2
One bar frame 3 and two guide bars 8 on both sides
And the second pipe holding body 4 is provided with one feeding mechanism portion 5 corresponding to one rod frame 3.

Besides, it is possible to use three or more rod frames 3 and to eliminate the guide bar 8.
With respect to the feed mechanism unit 5, when there are two or more rod frames 3, it is possible to provide them on all the rod frames 3 or to limit the number to one or more specific ones. Further, the feed mechanism section 5 can be replaced with a fluid pressure cylinder or a lever structure.

The radial pressing means 6 is the second pipe holder 4
Not only the first pipe holding body 2 but also the first pipe holding body 2 can be provided.
In addition, in each of the pipe holding bodies 2 and 4, the radial direction pressing means 6 is provided.
There can be only one or three or more. Also,
The advancing / retreating mechanism 41 included in the radial pressing means 6 is not limited to the screw feeding structure described above.

For example, although not shown in the drawings, the movement of bringing the pipe abutment body 40 into contact with or away from the pipe is performed by combining a link mechanism, a cam mechanism, a gear mechanism, or the like individually or in combination. It can be configured to be performed. Of course, it is also possible to press the pipe contact body 40 to the pipe in a pressure contact state as an extension of the contact operation with the pipe. Further, for this pressure contact, a screw feed structure as described in the first embodiment may be used.

By adopting such a configuration, it is possible to perform a predetermined movement of the pipe contact member 40 with a few operations (preferably one action), which is advantageous in improving work efficiency.

[0045]

As is apparent from the above description, claim 1
In the present invention described, the rod frame, the first and second pipe holding bodies provided along the rod frame, and one pipe holding body are provided so that both pipe holding bodies are close to each other. Since the first and / or second pipe holding bodies are provided with the radial direction pressing means, the first and second pipe holding bodies are provided on the pipe. The pipes can be joined or separated from each other by holding and holding them and operating the feed mechanism.

Further, in these cases, since the first and / or second pipe holding bodies are provided with the radial pressing means, the pipe holding force is tough and reliable, and the size or weight is large. Even when joining a large-sized pipe or a pipe having a hard packing, or when joining with a large amount of compressive deformation of the packing, desired pipe joining is possible.

If a screw feed structure is adopted for the advancing / retreating mechanism as the radial pressing means (claim 2), there is an advantage that the pipe pressing by the radial pressing means can be reliably set to a desired pressure. This is excellent in that the pipes can be joined under the same conditions even when the pipe diameters are different. In addition, since the structure can be simple and small, there is an advantage that an increase in manufacturing cost can be suppressed.

The first and / or second pipe holding body is a main body which can come into contact with the outer peripheral surface of the pipe at at least two points, and a main body from one end of the main body through the outer peripheral surface of the pipe. It is possible to have a configuration including a flexible diaphragm body that is stretched over the other end of the portion, and diaphragm means that can adjust the effective span of the flexible diaphragm body with respect to the main body portion. ). Further, it is preferable to use a chain as the flexible diaphragm (claim 4). With this structure, the flexible throttle body (chain) has high flexibility, and there is an advantage that the winding state around the pipe can be ensured even when the pipe diameters are various, and the overall structure is lightweight and sturdy. In addition, there are various advantages that it is possible to prevent an increase in size and a rise in manufacturing cost.

[Brief description of drawings]

FIG. 1 is a front view showing a first embodiment of the present invention.

FIG. 2 is a perspective view showing the first embodiment by partially crushing it.

FIG. 3 is an enlarged cross-sectional view showing a throttle means provided on the first and second pipe holding bodies.

FIG. 4 is a perspective view showing a hook portion of a flexible diaphragm provided on the first and second pipe holding bodies.

FIG. 5 is a front view showing radial pressing means provided on a second pipe holder.

FIG. 6 is an exploded perspective view showing a radial pressing means.

FIG. 7 is a plan sectional view showing a pressing pad provided on the first and second pipe holding bodies.

FIG. 8A is a side view for explaining a joining state of pipes, and FIG. 8B is a side view for explaining a separating state of the pipes.

FIG. 9 is a perspective view showing a second embodiment of the present invention by partially crushing it.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Tool 2 1st pipe holding body 3 Bar frame 4 2nd pipe holding body 5 Feed mechanism part 6 Radial direction pressing means 14 Throttling means 40 Pipe contact body 41 Advancement / retraction mechanism

Claims (4)

[Claims] 1. A rod frame (3), first and second pipe holders (2, 4) provided along the rod frame (3), and one pipe holder (4). A first and / or second pipe holding body (2, 4) which is provided in the first pipe and the second pipe holding body (2, 4) to relatively approach or separate from each other. The holding bodies (2) and (4) include a pipe contacting body (40) capable of contacting the held pipe, and an advancing / retreating mechanism (41) for moving the pipe contacting body (40) in the radial direction of the pipe. A pipe joining tool, characterized in that it is provided with a radial pressing means (6) having 2. The pipe joining tool according to claim 1, wherein a screw feed structure is used for the advancing / retreating mechanism (41) in the radial pressing means (6). 3. The first and / or second pipe holders (2) (4), and a main body portion (12) which can come into contact with the outer peripheral surface of the pipe at at least two positions, and the main body. Department (1
2) A flexible diaphragm body (15) which is bridged from one end portion to the other end portion of the main body portion (12) via the outer peripheral surface of the pipe, and a flexible diaphragm body (15) which is hung on the main body portion (12). The pipe joining tool according to claim 1 or 2, further comprising a squeezing means (14) capable of adjusting an effective transfer length. 4. The pipe joining tool according to claim 3, wherein a chain is used as the flexible throttle body (15).