JP5237918B2 - Pull-in device - Google Patents

Description

  In the present invention, when replacing a new pipe while cutting an existing pipe through an existing pipe by non-excavation and tearing the existing pipe, the end of the existing pipe is pressed to easily recover the cut diameter expander after completion of construction. Relates to the improvement of the pull-in device.

The pipe splitter method is a method of tearing an existing pipe with a cutting and expanding tool such as Japanese Patent No. 3217403 and Japanese Patent No. 4081506, and pulling in a new polyethylene pipe while expanding the diameter. Therefore, it has been actively introduced from the viewpoint of reducing the environmental burden by reducing the excavation area and the construction cost.
The retracting machine of the above construction method is constructed by pressing the tip of an existing pipe and drawing the cutting diameter expanding tool through the existing pipe using the force as a reaction force.
Therefore, the end part of the existing pipe on the retracting machine side will bite into the existing pipe end part without allowing the cutting diameter expansion tool to pass through, so the end part of the existing pipe is cut off and removed using a large hammer or heavy equipment. The work which removes an existing pipe and a cutting diameter expansion tool has generate | occur | produced, and the improvement of workability | operativity and safety was calculated | required.
Thus, for example, in the traction device disclosed in Japanese Patent Application Laid-Open No. 2002-227589, a first transmission tool (a pair of left and right arms) capable of transmitting the traction reaction force of the retracting machine to the tip 41 side of the existing pipe 40 exposed inside the pit. 5 'and a hooking portion 6' at the tip thereof, and a second transmission tool (such as a frame 3 ') capable of transmitting the traction reaction force to the inner surface side of the pit, the second transmission tool, The first transmission is provided inside the pit and on the upper side in the pulling direction of the retracting machine so as to be able to secure a space in which a tube breaking tool (cutting diameter expanding tool) can be pulled out over substantially the entire length. A receiving position shown by a solid line capable of receiving the other end of the existing pipe from the longitudinal direction of the pipe, and a retreat position where the receiving is released and does not interfere with the pipe breaking tool drawn out inside the pit. It is configured to be freely movable ( Reference 19).
However, in the above configuration, when the tube breaker is pulled to the vicinity of the existing pipe, the first transmission tool that has collided with the tip of the existing pipe is a retreated position in which the arm is separated to pull out the tube breaker. Therefore, after that, the tip of the existing pipe is in a free state, and the pipe breaker is pulled only by the second transmission member such as the frame such as a rod.
Therefore, even if a slightly biased force is applied during traction, the traction reaction force is not transmitted evenly to the existing pipe, and the existing pipe is tilted and the tube breaker is clogged, or the tube breaker is tilted and the pipe breaker is placed in the existing pipe. There is a problem that the conventional defect cannot be solved.
Therefore, Japanese Patent No. 4107615 has been proposed as a traction device composed of a non-cutting pipe support member, an expanded diameter pipe support member, a frame body, and a retracting machine, and has a corresponding effect. It came to be completed.

Japanese Patent Laid-Open No. 2002-227589 See FIG. Japanese Patent No. 4107615

  The present invention has been made in view of the above circumstances, and the main problem is that a member that uses the traction reaction force to the existing pipe until the cutting diameter increasing tool that becomes the head comes near the tip of the existing pipe, and thereafter It is another object of the present invention to provide a retractor that can be transmitted to an existing pipe in two stages by cutting the tip of the existing pipe and removing it from the member.

In order to solve the above problem, the invention of claim 1
It has a traction device that pulls the cutting diameter expansion tool inserted from one end side of the existing existing pipe toward the other end side, and connects to the cutting diameter expansion tool while cutting and expanding the existing pipe wall along the pulling direction. In the pull-in device that pulls in and replaces the newly installed pipe,
A storage space that is fixed in the pit on the towing side and can store the retracted cutting diameter expanding tool, a support base having an opening from which the cutting diameter expanding tool can be taken out, and pivotally attached to the left and right sides of the support base. A pair of left and right support arms that open and close the storage space,
A receiving surface main body provided with an insertion hole through which a pulling member such as a wire or a rod for pulling the cutting diameter expanding tool is brought into contact with the distal end surface of the existing pipe, and the receiving surface connected to the upper portion of the receiving surface main body It consists of a fixed piece that fixes a pair of support arms that support the main body in a position to close the storage space, and transmits the traction reaction force to the existing pipe until it is pulled near the tip of the existing pipe. A first transmission member;
A main body plate supported by the support arm or supported by a support base via a fixing member; an arc-shaped support surface portion that abuts with an upper portion of the tip end surface of the existing pipe at the lower portion of the main body plate; and the support surface portion And a supporting protrusion and a hooking protrusion formed in a substantially concentric large-diameter arc shape. A cutting and expanding tool is pulled out from the vicinity of the tip of the existing pipe instead of the base 1 transmission member. And a second transmission member that transmits the traction reaction force to the existing pipe.
In the invention of claim 2,
The second transmission member is formed at the center of the lower end of the main body plate, and has a bearing surface portion that is set to be substantially the same or slightly wider corresponding to the thickness of the upper end of the existing pipe, and extends along the outside of the bearing surface portion. The projecting part protrudes forward and is set to a substantially concentric large-diameter arc-shaped projecting step, and engages with the bearing surface part. It is characterized by comprising a fixing member that is fixed to the frame body in a state of being rotated at an arbitrary angle parallel to the distal end surface.
In the invention of claim 3,
The second transmission member has a wide body plate that can be supported with the support arm pivoted outwardly to open the center space of the support base, and the upper end of the existing pipe formed at the center of the lower end of the body plate Corresponding to the thickness of the bearing surface, set to a substantially equal width or a slightly wider width, and a projecting step having a substantially concentric large-diameter arc shape projecting forward along the outside of the bearing surface portion. It has a latching protrusion piece part which latches the outer peripheral wall of the tip upper part of the existing pipe which abuts on a bearing surface part.
In the invention of claim 4,
The plate body includes a plate body set to have a width equal to or greater than the width of the support base, and an inverted U-shaped hole that extends downward from a midway position at the center of the plate body and opens at the lower end. The width of the tube is set to be approximately the same as or slightly larger than the diameter of the existing pipe, and is arranged along the inner wall surface of the reaching pit and pressed by the front end surface of the support base to protrude the front end of the existing pipe from the hole. A positioning member fixed in a state is provided.

In the present invention, when the cutting diameter expanding tool is pulled from the existing pipe, in order to transmit the traction reaction force to the existing pipe, the cutting diameter expanding tool is in the existing pipe and is moved until it moves to the tip of the existing pipe. The first transmission member is used in order to increase the area and bring the left and right support arms closer to hold down the existing pipe.
When the cutting diameter expander comes to the tip, the support arm is separated to open a space, and the cutting pipe is pulled out of the existing pipe by pressing the existing pipe securely with the undeformed portion of the tip of the existing pipe. Therefore, the second transmission member is used.
Thereby, it can cut with a cutting diameter expanding tool to the front-end | tip of an existing pipe, and a cutting diameter expanding tool can be drawn in in an arrival pit.

It is a disassembled perspective view which shows the unit of a support base. It is a disassembled perspective view which shows the connection of a support base. It is a top view in the state where the 1st transmission member was equipped in the support base. It is a front view of a positioning member. It is a rear view of a 1st transmission member. (A) is a top view of a 1st transmission member, (b) is a bb sectional view taken on the line. It is a rear view which shows arrangement | positioning of the positioning member and the 1st transmission member which showed the support base and the existing pipe with the dotted line. It is a top view which shows the use condition of a 1st transmission member. It is a top view which shows the mounting state of a 2nd transmission member. (A) is a front view of a 2nd transmission member, (b) is the center longitudinal cross-sectional view of a 2nd transmission member. (A) is a rear view which shows the state which supports the 2nd transmission member with the latching | locking part of the support arm shown with a dotted line, (b) is a side view of the 2nd transmission member. It is a top view which shows the use condition of a 2nd transmission member. It is a top view which shows the state which used the 2nd transmission member, and made the cutting diameter expansion tool pulled out from the existing pipe. It is a top view which shows the mounting state of the 2nd transmission member of 2nd Example. It is a front view of the 2nd transmission member. It is the exploded view seen from the side which shows the attachment state of the 2nd transmission member. It is a top view which shows the mounting state which changed direction of the 2nd transmission member. It is a different Example which reversed the direction of the support arm back and forth, (a) is a top view of the state which mounted | wore the 1st transmission member, (b) is a top view of the state which mounted | wore the 2nd transmission member. It is a top view which shows an example of the conventional traction apparatus.

  Hereinafter, an embodiment in which the drawing device of the present invention is applied to a pipe splitter method for a buried pipe for gas supply will be described with reference to the drawings.

[Pipe splitter method]
The pipe splitter construction method (non-open cutting replacement construction method) of the existing pipes buried is the same as the conventional one (see, for example, FIG. 1 of JP-A-2002-227589).
That is, although not shown, the starting pit and the reaching pit are excavated on both ends of the existing pipe buried in the replacement range, and the end of the existing pipe is projected into each pit.
A retracting device is arranged in the arrival pit.

In this embodiment, a wire (may be a rod that can be added and separated) is passed through the existing pipe as a pulling member, and the new pipe is connected to the tip of the wire on the arrival pit side via a cutting diameter increasing tool. To do.
Next, the wire is pulled to the arrival pit side by the pulling device connected to the pulling device, the existing pipe is cut in the longitudinal direction by the cutting diameter increasing tool, and the new pipe is drawn while expanding the hollow of the existing pipe.
Then, the cutting tool is pulled out from the existing pipe into the arrival pit, and the replacement is completed through the new pipe over the entire length of the existing pipe in the replacement range.

[Retraction device]
As shown in FIGS. 8 and 13, the retracting device 1 is connected to a tractive device (not shown) that pulls the wire 51 (or a pulling device that pushes and pulls the rod) and extends in the pulling direction to form a head. The inner wall surface 61 of the pit 60 has a space S1 in which the entire diameter expanding tool 50 can be accommodated, and an opening S2 in which the cutting diameter expanding tool 50 can be taken out on the upper surface and / or the side surface. Of the support base 2 in which the distal end 41 of the existing pipe 40 is disposed on the left and right side surfaces of the support base 2 and is exposed to the inside of the pit. It has a pair of support arms 5 that can pivot toward substantially the center.

  Further, a first transmission member 10 (see FIG. 8) that is detachably supported by the support arm 5 and transmits the traction reaction force of the traction device to the tip 41 of the existing pipe 40 that protrudes to the arrival pit 60, and the support A second transmission member 20 (see FIGS. 12 and 13) that is detachably supported by the arm 5 or the support base 2 and transmits the traction reaction force of the traction device to the tip 41 of the existing pipe 40 that protrudes to the arrival pit 60. It has.

[Support base]
The support base 2 transmits a reaction force pulling the cutting diameter expanding tool 50 to the inner wall surface 61 in the reaching pit 60 and transmits a pulling reaction force to the end surface of the tip of the existing pipe 40, which will be described later. The second transmission member 20 is supported.
In the case of the present embodiment, as shown in FIG. 1 to FIG. 2, an appropriate number (in the arrival pit 60), with the frame body 3 in which a steel square pipe is framed along a ridge line of a rectangular parallelepiped (may be a cube) In FIG. 13, three are used) connected in series.

In the present embodiment, the traction device is connected to the rearmost frame (denoted as 3C for explanation), and the leading frame (denoted as 3A for descriptiveness) is provided with a positioning member 30 that also serves as a retaining material, which will be described later. Via the inner wall surface 61 with no gap.
Here, “front and back” is described with the upstream side in the pulling direction in the reaching pit 60 as the front and the downstream side as the rear.
Further, the hollow portion of the frame body 3 penetrates in the pulling direction to form a space S1 in which the entire length of the cutting diameter expanding tool 50 can be accommodated, and each frame body 3 has an opening S2 on the upper side and the side. Therefore, the cutting diameter expanding tool 50 can be taken out of the frame.

  In the illustrated example, the frame 3 includes a rectangular lower frame portion 3a, four corner column portions 3b erected from four corners of the lower frame portion 3a, and a rectangular shape fixed on each column portion 3b. The upper frame portion 3c is composed of the frame material, but for the connection, the front and / or rear frame material of the upper frame portion 3c is omitted, and the shape composed of the left and right frame materials is used as the basic shape, and the frame body 3 is moved forward and backward When connecting, it connects with the connection frame material 4. FIG.

[Connection frame material]
The connecting frame material 4 includes a main body portion 4a formed integrally with a rear frame material and a front frame material constituting the upper frame portion of the adjacent front and rear frame bodies 3, and a connecting bracket 4b extending in the front and rear sides at the upper portion thereof. The main body portion 4a is fitted on the left and right corner column portions 3b, and the connecting bracket 4b is fixed to the left and right frame members to be the upper frame portions 3c of the front and rear frame bodies 3 with bolts and nuts.
Further, only the same connecting bracket 4b is applied from below to the left and right frame members which are the lower frame portions 3a of the front and rear frames, and fixed with bolts (see FIG. 2).

Further, the frame disposed at the foremost and rearmost ends protrudes only rearward or frontward into the main body 4a ′ made of the front or rear frame material of the upper frame portion on the front or rear frame material of the upper frame portion 3c. The frame 3 is completed by fitting the end connecting frame member 4 ′ to which the connecting bracket 4b ′ to be fixed is fitted.
In this case, if the U-shaped frame part is formed integrally without the frame material on either the front or rear side of the upper frame part, it is used as the upper frame part of the frame used at the forefront or rearmost. be able to.
In the present invention, the frame structure and the frame connection structure are not limited to the above-described embodiments, and a known frame structure can be used as appropriate.

[Support arm]
As shown in FIG. 3, the support arm 5 is composed of a pair of arms that are pivotally attached to the left and right sides at the rear in the frame 3 and extend to the front side of the frame. It has the latching | locking part 6 for hold | maintaining the 1st transmission member 10 and the 2nd transmission member 20 so that attachment or detachment is possible.
In the illustrated example, the latching portion 6 is formed of a columnar member having a latching step portion 6a on the front surface and extending vertically in the shape of a cross section L, and is pivotally attached to the tip of the support arm 5. Further, the latching portion 6 may be fixed integrally, or the latching portion 6 may be fixed in a state where the angle of the latching portion 6 with respect to the support arm 5 is adjusted to an arbitrary angle.

  The support arm 5 can pivot the tip side (the latching portion 6 side) toward the center of the front side of the support base 2 to firmly support the first transmission member 10, and to the left and right outer sides. By opening, the central space S <b> 1 of the support base 2 can be opened and the cutting diameter expanding tool 50 can be drawn into the support base 2.

[Towing device]
In the case of this embodiment, the traction device is a known winding device that pulls the wire 51 connected to the cutting diameter increasing tool 50, and a motor-driven winding drum (not shown) is provided outside the reaching pit 60. ) And a relay roller 8 that pivots the horizontally pulled wire 51 upward is pivotally supported at the rear of the last frame 3C of the support base 2, and the wire 51 is connected to the winding drum. It can be extended or rolled up (see FIG. 13).
As a member for pulling the cutting diameter expanding tool 50, a rod that can be extended and disassembled instead of a wire may be used, and in that case, a known push-pull machine may be used as the pulling device.
In addition, the structure of the traction device is not particularly limited in the present invention.

[Positioning member]
As shown in FIG. 4, the positioning member 30 has a pair of grips 32 on the upper part of a plate body 31 made of a steel plate set to a width equal to or greater than the width of the frame 3 of the support base 2. In the center of the main body 31, there is an inverted U-shaped elongated hole 33 that extends downward from the midway position and opens at the lower end, and the distal end 41 of the existing pipe 40 is inserted into the elongated hole 33.
The lateral width of the long hole portion 33 is set to be approximately the same as or slightly larger than the diameter of the existing pipe 40.

The positioning member 30 is in contact with the inner wall surface 61 of the reaching pit 60, the tip 41 of the existing pipe 40 is protruded from the elongated hole portion 33, and the reaching pit 60 is projected by the front surface of the frame body 3 </ b> A of the support base 2. Since it is pressed and fixed to the inner wall surface 61, the tip 41 of the existing pipe 40 can be restrained from moving in the left-right direction and the upward direction by pulling reaction force when the wire is pulled (see FIG. 3).
The positioning member 30 can be easily removed after use by pulling upward with the handle 32.
Since the positioning member 30 is a flat plate, it also functions as a retaining material (sheet pile).

[First transmission member]
The first transmission member 10 is supported by the support arm 5 and abuts with the tip 41 of the existing pipe 40 to transmit the traction reaction force due to the wire traction of the traction device to the existing pipe 40. As shown in FIG. 6, a plate-shaped receiving surface body 11 having an abutting surface 12 that abuts the tip 41 of the existing pipe 40 and an insertion hole 13 for inserting the wire 51, Arm fixing means provided on the upper portion for fixing the latching portion 6 of the support arm 5.

  In the first transmission member 10 of the present embodiment, as the arm fixing means, the fixing piece 15 having an angled cross section and the laterally extending piece 16 extending horizontally of the fixing piece 15 are provided spaced apart from each other at a predetermined interval. A pair of U-shaped constraining holes 17 that are open at the ends, a plate-shaped receiving surface body 11 that hangs between the pair of constraining holes 17, and a downward position from the middle position of the receiving surface body 11 It has an inverted U-shaped wire insertion hole 13 that extends and opens at the lower end.

  The lateral width of the fixed piece 15 is set to be the same as or slightly shorter than the lateral width of the frame body 3 of the support base 2 and is fitted to the inner front side of the front frame body 3A. Both sides are latched by the latching step part 6a of the latching part 6, and at the same time, the boss part 7 on the upper part of the latching part 6 is fitted in the restraining hole 17 of the laterally facing piece 16, and the first transmission with the support arm 5 The members 10 can be fixed to each other and simultaneously.

  Further, the abutting surface 12 is preferably formed with a U-shaped recess having a central portion that is recessed to substantially the same width as the diameter of the existing tube 40, and the end of the existing tube is abutted against the recessed surface 12a. Since the outer peripheral wall of the tip 41 of the existing pipe 40 is restricted by the left and right step portions 12b, the tip can be restrained in the left-right direction.

The pair of restraining holes 17 are externally fitted to the bosses 7 projecting vertically from the upper surfaces of the pair of latching portions 6, and the interval between the pair of latching portions 6 is fixed. It is restrained not to move.
At this time, the end surface of the tip 41 of the existing pipe 40 can abut the receiving surface main body in the entire area excluding the insertion hole 13 of the wire 51, so that the abutting area is widened.
Further, in order to exert a strong traction force, the support arm 5 supports the first transmission member 10 in a state where the end of the latching portion 6 is approached, that is, the storage space S1 is closed. Therefore, a strong traction reaction force can be transmitted to the existing pipe 40.

Therefore, the tip 41 of the existing pipe 40 is brought into contact with the first transmission member 10 until the cutting diameter increasing tool 50 is pulled out to the vicinity of the tip 41 of the existing pipe 40.
When the cutting diameter increasing tool 50 reaches a position near the tip 41, the first transmission member 10 is pulled upward, and the support arm 5 is pivoted both left and right to open the storage space S1, and the upper frame. Move to the left and right frame material side of the body 3a.
The second transmission member 20 is attached to the latching portion 6 of the support arm 5.

[Second transmission member]
The second transmission member 20 is wide enough to be hooked on the latching step portion 6a of the latching portion 6 in a state where the support arm 5 is abutted against the left and right frame members of the upper frame portion 3c of the frame 3A. The main body plate 21 has a length corresponding to the upper end of the existing pipe 40 when it is hooked on the support arm 5, and the diameter of the existing pipe 40 formed at the center of the lower end of the main body plate 21. The bearing surface 22 having a circular arc shape corresponding to the thickness of the existing pipe 40 and having a width substantially the same as or slightly wider than the existing tube 40, and projecting forward along the outer side of the bearing surface portion 22. A hooking protrusion 23 for hooking the outer peripheral wall of the tip 41 of the existing pipe 40 which is set to the projecting step of the arc shape and abuts the support surface 22, and a handle 24 provided on the upper part of the main body plate 21. (See FIGS. 9 and 10).

The second transmission member 20 is used to transmit a traction reaction force to the existing pipe 40 when the cutting diameter increasing tool 50 in the vicinity of the tip of the existing pipe 40 is pulled out from the existing pipe 40. It is inserted in the front in 3A, is latched by the latching step part 6a of the latching part 6 of the said support arm 5, and is hold | maintained in parallel with the end surface of the front-end | tip 41 of the existing pipe 40.
Then, the end surface of the tip 41 of the existing pipe 40 is brought into contact with the support surface 22, and the outer peripheral wall of the contacted tip 41 is restrained by the latching protrusion piece 23.

Since the existing pipe 40 is normally cut off in the longitudinal direction by the cutting diameter increasing tool 50 and expanded outward, the shape of the upper part of the existing pipe 40 is not deformed.
Therefore, no matter how the lower part of the existing pipe 40 is deformed, the upper part of the existing pipe 40 that is not deformed can be reliably abutted and restrained by the second transmission member, so that the traction reaction force is transmitted to the end of the existing pipe 40. can do.
Thereby, the cutting diameter expanding tool 50 can be pulled out into the storage space S <b> 1 of the support base 2 through the second transmission member 20 while cutting the lower end portion of the existing pipe 40.

As shown in FIG. 11, the second transmission member 20 has a back surface of the main body plate 21 corresponding to the upper portion of the main locking projection piece 23 so as to hold the space between the support arms 5 and hold the locking portion of the support arm 5. A restriction piece 21a for fixing 6 with the left and right frame members of the upper frame portion 3c may be provided.
Thereby, the tip 41 of the existing pipe 40 is cut by the cutting diameter increasing tool 50 through the wire 51 by the traction device, and is supported by the second transmission member 20 until the cutting diameter expanding tool 50 is completely pulled out from the existing pipe 40. The

When the position where the existing pipe 40 is torn by the cutting diameter expanding tool 50 is the side or upper position of the existing pipe 40, the deformed portion of the existing pipe 40 is the side or upper position. Therefore, the end face of the tip 41 of the existing pipe 40 cannot be brought into contact with the entire support surface portion 22.
Therefore, the second transmission member 20 ′ shown in FIGS. 14 to 17 shows a different embodiment that can collide with and hold an arbitrary position at the tip of the existing pipe 40.

When the second transmission member 20 ′ is attached to the support base, the second transmission member 20 ′ has a small and narrow main body plate 21 ′ with a height corresponding to the upper part of the existing pipe 40 as a lower end, and a lower center of the main body plate 21. The support surface 22 ′ and the latching protrusion 23 ′ having the same configuration as in the above embodiment and the main body plate 21 ′ are rotated in parallel with the end face of the tip 41 of the existing pipe 40 at an arbitrary angle. And a fixing member 25 fixed to the frame body.
Here, the fixing member 25 is fixed to the back surface of the main body plate 21 ′ and has a cylindrical portion 26 that extends rearward, a screw rod 27 that can be fitted into the cylindrical portion 26, and a screw rod 27 that can be screwed back and forth. A stopper member 28 having a nut structure that is screwed onto the screw rod 27, and a frame latching portion 29 fixed to the end of the screw rod 27.

Therefore, the main body plate 21 ′ is rotated around the axis of the cylindrical portion 26 so that the bearing surface portion 22 ′ corresponds to the portion corresponding to the tearing portion of the end face 41 of the tip 41 of the existing pipe 40, and the cylindrical portion 26 The screw rod 27 is inserted into the frame body and the frame body latching portion 29 is latched to the frame body 3. In this state, the stopper member 28 is screwed to extend the entire length, and the body plate 21 ′ is fastened to the tip of the existing pipe 40. To do.
As a result, regardless of the position of the existing pipe 40 where the tearing portion by the cutting diameter expanding tool 50 is located, the non-deformed portion of the tip 41 of the existing pipe 40 is firmly secured by the second transmission member 20 ′ at the opposite position avoiding this. Can be supported.
Since the tip 41 of the existing pipe 40 is reliably supported by the second transmission member 20 ′, the tip 41 is cut by the cutting diameter increasing tool 50 through the wire 51 by the traction device, and the cutting diameter expanding tool 50 is completely removed from the tip 41. The pulling reaction force can be transmitted to the existing pipe 40 until it is pulled out.

  Since the present invention has the above-described configuration, the first transmission is performed by bringing the ends of the pair of support arms 5 closer to the center of the support base 2 while the cutting diameter increasing tool 50 is being pulled in the existing pipe 40. Since the member 10 is strongly supported and the traction reaction force can be transmitted to almost the entire region except for the lower portion of the tip 41 of the existing pipe 40, the wire 51 can be pulled along substantially the axis of the existing pipe 40.

  Then, when the cutting diameter increasing tool 50 comes to the vicinity of the tip 41 of the existing pipe 40, the tip of the support arm 5 is separated from the left and right outwards to open the storage space S1, and the second transmission instead of the first transmission member 10 is opened. Since the member 20 ′ is mounted in the support base 2 and the portion where the existing pipe 40 is not deformed can be reliably supported, and the wire 51 can be pulled along substantially the axis of the existing pipe 40, the cutting diameter increasing tool 50, the existing pipe 40 can be continuously cut to the tip 41, and the cutting diameter expanding tool 50 can be pulled out from the tip of the existing pipe 40 and drawn into the storage space S1 in the support base 2.

In the above-described embodiment, the structure in which the frame body is connected is illustrated as the support base. However, as long as the support base has a support arm and has a storage space for a cutting diameter expanding tool and an opening for taking out, any configuration is possible. It may be.
The support arm may be pivotally attached to the front of the support base (see FIG. 18).
In addition, the present invention is not limited to the above-described embodiments, and it goes without saying that various design changes can be made without changing the gist of the present invention.

DESCRIPTION OF SYMBOLS 1 Pulling-in apparatus 2 Support base 3 Frame body 3a Lower step frame part 3b Corner column part 3c Upper step frame part 4 Connection frame material 4a Main body part 4b Connection bracket 5 Support arm 6 Latch part 6a Latch step part 7 Boss part 8 Relay roller DESCRIPTION OF SYMBOLS 10 1st transmission member 11 Reception surface main body 12 Contact surface 13 Insertion hole 15 Fixing piece 16 Lateral piece 17 Restraining hole 20 2nd transmission member 21 Main body plate 22 Supporting surface part 23 Latching protrusion piece part 24 Handle 25 Fixing member 26 Cylindrical part 27 Screw rod 28 Stopper member 29 Frame latching portion 30 Positioning member 31 Plate body 32 Handle 33 Long hole portion 40 Existing tube 41 Existing tube tip 42 New tube 50 Cutting diameter expanding tool 51 Wire 60 Reaching pit 61 Existing tube protrudes Inner wall

Claims (4)

It has a traction device that pulls the cutting diameter expansion tool inserted from one end side of the existing existing pipe toward the other end side, and connects to the cutting diameter expansion tool while cutting and expanding the existing pipe wall along the pulling direction. In the pull-in device that pulls in and replaces the newly installed pipe,
A storage space that is fixed in the pit on the towing side and can store the retracted cutting diameter expanding tool, a support base having an opening from which the cutting diameter expanding tool can be taken out, and pivotally attached to the left and right sides of the support base. A pair of left and right support arms that open and close the storage space,
A receiving surface main body provided with an insertion hole through which a pulling member such as a wire or a rod for pulling the cutting diameter expanding tool is brought into contact with the distal end surface of the existing pipe, and the receiving surface connected to the upper portion of the receiving surface main body It consists of a fixed piece that fixes a pair of support arms that support the main body in a position to close the storage space, and transmits the traction reaction force to the existing pipe until it is pulled near the tip of the existing pipe. A first transmission member;
A main body plate supported by the support arm or supported by a support base via a fixing member; an arc-shaped support surface portion that abuts with an upper portion of the tip end surface of the existing pipe at the lower portion of the main body plate; and the support surface portion And a hooking projection piece formed in a substantially concentric large-diameter arc shape that protrudes along the outside of the tube, and a cutting diameter expanding tool is drawn out from the vicinity of the tip of the existing pipe instead of the first transmission member. And a second transmission member that transmits the traction reaction force to the existing pipe.   A second transmission member is formed at the center of the lower end of the main body plate, and has a bearing surface portion set to be substantially the same or slightly wider corresponding to the thickness of the upper end of the existing pipe, and along the outside of the bearing surface portion. A projecting protrusion that protrudes forward and is set to a substantially concentric large-diameter arc-shaped projecting step and abuts against the bearing surface. The retraction device according to claim 1, comprising a fixing member that is fixed to the frame body in a state of being rotated at an arbitrary angle in parallel with the surface.   The second transmission member pivots the support arm outward to open the central space of the support base, and a wide body plate that is supported at the center of the lower end of the main body plate. The bearing surface is set to have the same or slightly wider width corresponding to the wall thickness, and the projection is set to a substantially concentric large-diameter arc-shaped projecting step along the outside of the bearing surface. The retracting device according to claim 1, further comprising a latching protrusion piece that latches an outer peripheral wall of an upper end of an existing pipe that abuts the surface portion.   The plate body is set to have a width equal to or greater than the width of the support base, and an inverted U-shaped hole that extends downward from an intermediate position in the center of the plate body and opens at the lower end. The width is set to be almost the same as or slightly larger than the diameter of the existing pipe, and is arranged along the inner wall surface of the reaching pit and pressed by the tip surface of the support base so that the tip of the existing pipe protrudes from the hole. The retracting device according to claim 1, further comprising a positioning member that is fixed in place.

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