JP3799583B2 - Bolt fastening mechanism - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a bolt fastening mechanism used when fastening between segments in a shield method.
[0002]
[Prior art]
The shield construction method is a construction method in which a shield excavator having a face on the front is propelled into the ground, and a tunnel is constructed while excavating and lining work safely inside the ground while preventing the surrounding ground from collapsing. The tunnel portion is divided into a plurality of pieces called segments in the circumferential direction, and is assembled by a segment automatic assembly robot. In addition, the segments are fastened with bolts by a bolt fastening machine mounted on the segment automatic assembly robot so that the assembled segments do not fall or slip.
[0003]
Here, FIG. 3 is a cross-sectional view when the segment is cut along a plane perpendicular to the bolt fastening surface of the segment. As shown in this figure, the segments are fastened by a nut runner that is a tip of a bolt fastening machine and screwes a nut onto a bolt. A box hole for inserting a nut runner is formed in the segment, and a bolt hole is drilled in a bolt fastening surface of the box hole so that the bolt can penetrate when the segment is assembled. Moreover, the bolt is set in the box hole of one segment as shown by the broken line before fastening, and penetrates the bolt hole by compressed air sent to the box hole at the time of fastening. Although not shown, instead of sending compressed air to the box hole facing the box hole into which the nut runner is inserted (the box hole to which compressed air is sent in the figure), it is attached to the tip of the bolt fastening machine. In some cases, the bolt holder provided is inserted, and the bolt and nut are clamped between the bolt holder and the nut runner.
[0004]
[Problems to be solved by the invention]
As described above, since the bolt fastening machine is mounted on the segment automatic assembly robot, weight reduction and space saving are desired. There is also a desire to make the box holes of the segments as small as possible. This is required because of the fact that post-processing such as embedding the box hole with concrete after bolt fastening, and that reinforcing bars are arranged in the segments. Therefore, the nut runner must be downsized and simplified.
[0005]
On the other hand, the bolts used for fastening the segments are of the same size as much as possible, but the earth pressure applied to the tunnel due to the sedimentary layer and the ground structure where the tunnel is built is limited. In some cases, it is unavoidable to use parts that are partly different in size. In such a case, the nut runner socket may be replaced according to the size of the bolt. However, as described above, the bolt fastening machine has been considerably downsized and simplified, and the socket cannot be replaced. is there. Therefore, when the bolt sizes are different, one of (1) manually fastening the bolt and (2) replacing the bolt fastening machine itself has to be adopted.
[0006]
However, in the method (1), a scaffold must be installed in a narrow place, which is a dangerous work. There are also cases where a large tunnel is out of reach. In the method (2), it is necessary to secure a place to store the unused bolt fastening machine, which is expensive. When using multiple bolt sizes, prepare the bolt fastening machine accordingly. There was a problem such as having to.
[0007]
The present invention has been developed to solve such problems. That is, an object of the present invention is to provide a bolt fastening mechanism that can fasten between segments with one bolt fastening machine even if the bolt sizes are different.
[0008]
[Means for Solving the Problems]
According to the present invention, in order to fasten the boundary surfaces of a plurality of segments forming a tunnel with a bolt, a nut runner for holding and rotating the nut is inserted into a box hole provided in the segment, and the nut is screwed into the bolt. A bolt fastening mechanism for joining, a socket that is provided in the nut runner and that can hold a nut that fits the largest bolt used in the construction of the tunnel, and is attached to the socket, There is provided a bolt fastening mechanism comprising a variable size metal fitting having a rectangular hole capable of holding a nut adapted to a small bolt. Further, a magnet for attracting the nut may be provided at the back of the socket, and the position of the nut held by the socket may be adjusted according to the length of the magnet in the bolt axial direction. The socket and the size-variable metal fitting may also be used when a bolt holder is inserted into a box hole facing the hole.
[0009]
According to the configuration of the present invention described above, even if the bolt size for fastening the segments changes, it can be dealt with only by attaching a size-variable metal fitting, and all the segments can be fastened with one bolt fastening machine. And there is no need to install a scaffold. Moreover, a nut can be reliably hold | maintained and rotated with the said magnet, and a nut can be firmly screwed to a volt | bolt. Furthermore, the socket and the size-variable metal fitting can be applied to a bolt holder.
[0010]
Further, according to the present invention, in order to fasten the boundary surfaces of a plurality of segments forming a tunnel with a bolt, a nut runner that holds and rotates the nut is inserted into a box hole provided in the segment, and the nut is inserted into the bolt. A bolt fastening mechanism for screwing a socket, which is provided in the nut runner and can hold a nut that fits the largest bolt to be used for construction of a tunnel, and has the same outer shape as the nut Thus, there is provided a bolt fastening mechanism comprising a variable size nut having a tap hole that can be screwed into a bolt smaller than the bolt.
[0011]
According to the configuration of the present invention described above, even if the bolt size for fastening between the segments changes, it can be dealt with by simply changing the nut to a variable size nut, and all the segments can be fastened with one bolt fastening machine. There is no need to install a scaffold.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a preferred embodiment of the present invention will be described with reference to FIG. 1 and FIG.
FIG. 1 is an embodiment showing a bolt fastening mechanism of the present invention, which uses a size-variable metal fitting. 1, (A) shows a case where a nut that fits the largest bolt is screwed, (B) is a cross-sectional view taken along the line BB in FIG. 1 (A), and (C) is the largest bolt. The case where the nut which fits a smaller bolt is screwed is shown, (D) is a DD arrow sectional view in Drawing 1 (C). In addition, the figure of the volt | bolt is abbreviate | omitted in FIG. 1 (B), (D).
[0013]
As shown in this figure, the bolt fastening mechanism of the present invention is provided in a nut runner of a bolt fastening machine (see FIG. 3), and can hold a nut 2a that fits the largest bolt 1a used for construction of a tunnel. A socket 3 that can be mounted on the socket 3 and a variable-size metal fitting 4 having a rectangular hole that can hold a nut 2b that fits a bolt 1b smaller than the largest bolt 1a.
[0014]
For example, a case will be described in which the M42 bolt is used in the JIS standard display for most of the tunnel, and the M36 bolt is used in the JIS standard display only in a part thereof. In this case, it is considered that FIGS. 1A and 1B are diagrams in the case of using the M42 bolt 1a, and FIGS. 1C and 1D are diagrams in the case of using the M36 bolt 1b. be able to. As shown in FIGS. 1A to 1D, an M42 nut 2a is used for the M42 bolt 1a, and an M36 nut 2b is used for the M36 bolt 1b. At this time, since the maximum bolt size used for construction of the tunnel is M42, as shown in FIGS. 1A and 1B, the nut runner socket 3 is fitted in close contact with the nut 2a of M42. Use the best match. Further, a ring-shaped magnet 5 is provided at the back of the socket 3 to attract the nut 2a. Even if the socket 2 is used to hold and rotate the nut 36b of M36 as it is, the nut 2b cannot be held and rotated because the difference in diameter is 6 mm. Therefore, the size variable metal fitting 4 is used to fill this gap (diameter difference). The size-variable metal fitting 4 is a member having a strength capable of withstanding the torque when the nut 2b is rotated, and is surface hardened by, for example, quenching. The size-variable metal fitting 4 has a hollow prismatic shape (usually a hexagonal prism) having a flange portion 4f at one end. The outer peripheral surface thereof is in close contact with the inner peripheral surface of the socket 3, and the inner peripheral surface is M36. The shape is optimal for holding the nut 2b. Further, one or a plurality of bolt holes for mounting the size-variable metal fitting 4 to the socket 3 are perforated in the flange portion 4f, and are fixed by a set bolt 6. Therefore, even if the bolt size for fastening between the segments changes, it can be dealt with by simply attaching the size-variable metal fitting 4, and all the segments can be fastened with one bolt fastening machine, and a scaffold is installed. There is no need. When the M2 nut 2b is screwed, the height is lower than that of the M42 nut 2a, so there is a possibility that the M36 nut 2b cannot be firmly screwed to the bolt 1b as it is. In such a case, the position of the nut 2b held by the socket 3 may be adjusted by the length of the magnet 5 in the bolt axis direction. Of course, a spacer (not shown) may be inserted further into the magnet 5 to adjust the position of the nut 2b.
[0015]
In the above description of the embodiment of the present invention, the case of a nut runner has been described. However, when a bolt holder is used at the time of bolt fastening, the socket 3 and the size-variable metal fitting 4 described above are used for the bolt holder. It may be. This is because the nut runner and the bolt holder are the same with respect to holding the bolt or nut.
[0016]
FIG. 2 shows another embodiment of the bolt fastening mechanism of the present invention, which uses a variable size nut. 2, (A) shows a case where a nut that fits the largest bolt is screwed, (B) is a cross-sectional view taken along line BB in FIG. 2 (A), and (C) is the largest bolt. The case where the nut which fits a smaller bolt is screwed is shown, (D) is a DD arrow sectional view in Drawing 2 (C). In addition, the figure of the volt | bolt is abbreviate | omitted in FIG. 2 (B), (D).
[0017]
As shown in this figure, the bolt fastening mechanism of the present invention is provided in a nut runner of a bolt fastening machine (see FIG. 3), and a socket 9 that can hold a nut 8a that fits the largest bolt 7a to be used. The nut 8a has a variable size nut 8b having a tap hole 8t that has the same outer shape as the nut 8a and can be screwed into a bolt 7b smaller than the largest bolt 7a.
[0018]
For example, a case will be described in which the M42 bolt is used in the JIS standard display for most of the tunnel, and the M36 bolt is used in the JIS standard display only in a part thereof. In this case, it is assumed that FIGS. 2A and 2B are diagrams when the M42 bolt 7a is used, and FIGS. 2C and 2D are diagrams when the M36 bolt 7b is used. be able to. As shown in FIGS. 2A and 2C, the nut runner socket 3 is an optimum one that fits closely to the nut 42a of the M42. However, if the M42 nut 7a is used for the M42 bolt 7a and the M36 nut is used for the M36 bolt 7b, the difference in diameter between the M36 nut and the socket 3 is 6 mm. It cannot be rotated. Therefore, a variable size nut 8b is used instead of the M36 nut. As shown in FIG. 2 (D), the variable size nut 8b has the same outer shape (hexagonal shape) as the nut 8a of M42 shown in FIG. 2 (A), and can be screwed onto the bolt 36b of M36. Thus, it has the same tap hole 8t as the nut of M36. Therefore, even if the bolt size for fastening the segments changes, it can be dealt with by simply changing the nut to the variable size nut 8b, and all the segments can be fastened with one bolt fastening machine. There is no need to install it.
[0019]
In the description of the other embodiments of the present invention described above, the case of a nut runner has been described. However, when a bolt holder is used at the time of bolt fastening, a bolt having a head similar to the above-described variable size nut 4 is used. Alternatively, the size-variable metal fitting 4 may be used as in the embodiment shown in FIG.
[0020]
In addition, this invention is not limited to embodiment mentioned above, You may make it use the some size variable metal fitting 4 and the size variable nut 8b according to the kind of bolt size, and does not use the magnet 5. FIG. Of course, various modifications can be made without departing from the scope of the present invention.
[0021]
【The invention's effect】
As described above, according to the bolt fastening mechanism of the present invention, the socket of the nut runner (or bolt holder) of the bolt fastening machine is formed in accordance with the largest bolt used for the construction of the tunnel, and the bolt smaller than that is formed. In addition, if variable size metal fittings and variable size nuts are prepared, even if the bolt size between the segments changes, the segments can be fastened with a single bolt fastening machine, making it easy, quick, safe and inexpensive. It has an excellent effect such as being able to cope with.
[Brief description of the drawings]
FIG. 1 is an embodiment showing a bolt fastening mechanism according to the present invention, which uses a size-variable metal fitting. In addition, (A) shows the case where the nut which fits the largest volt | bolt is screwed together, (B) is BB arrow sectional drawing in FIG. 1 (A), (C) is larger than the largest volt | bolt. The case where the nut which fits a small volt | bolt is screwed together is shown, (D) is DD sectional view taken on the line in FIG.1 (C).
FIG. 2 is another embodiment showing the bolt fastening mechanism of the present invention, and uses a variable size nut. In addition, (A) shows the case where the nut which fits the largest volt | bolt is screwed together, (B) is BB arrow sectional drawing in FIG. 2 (A), (C) is larger than the largest volt | bolt. The case where the nut suitable for a small volt | bolt is screwed together is shown, (D) is DD sectional view taken on the line in FIG.2 (C).
FIG. 3 is a cross-sectional view of a segment cut along a plane perpendicular to the bolt fastening surface of the segment.
[Explanation of symbols]
1a, 7a M42 bolt (maximum bolt)
1b, 7b M36 bolt (small bolt)
2a, 8a M42 nut 2b M36 nut 3 Socket 4 Size variable bracket 4f Flange 5 Magnet 6 Set bolt 8b Size variable nut 8t Tap hole

Claims (4)

Bolt fastening when inserting a nut runner that holds and rotates a nut into a box hole provided in the segment and screwing the nut into the bolt in order to fasten the boundary surface of multiple segments forming the tunnel with a bolt Mechanism,
A socket that is provided in the nut runner and can hold a nut that fits the largest bolt used to build the tunnel;
A size-variable metal fitting having a rectangular hole that is attached to the socket and can hold a nut that fits a bolt smaller than the bolt,
A bolt fastening mechanism comprising: 2. The bolt fastening mechanism according to claim 1, wherein a magnet for pulling the nut is provided in a deep part of the socket, and a position of the nut held in the socket is adjusted by a length of the magnet in a bolt axial direction. The bolt fastening mechanism according to claim 1 or 2, wherein the socket and the size-variable metal fitting are used even when a bolt holder for holding a bolt is inserted into the box hole facing the box hole. Bolt fastening when inserting a nut runner that holds and rotates a nut into a box hole provided in the segment and screwing the nut into the bolt in order to fasten the boundary surface of multiple segments forming the tunnel with a bolt Mechanism,
A socket that is provided in the nut runner and can hold a nut that fits the largest bolt used to build the tunnel;
A variable size nut having a tap hole that has the same outer shape as the nut and can be screwed into a bolt smaller than the bolt,
A bolt fastening mechanism comprising:

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