JPH0364258B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a nut rotation system used in an automatic bolt fastening machine for automatically screwing together bolts and nuts that are previously provided facing each other on flanges to be connected. It is related to the device.

[Conventional technology]

For example, when a shield tunneling machine is propelled to assemble segments into a tunnel to complete the lining, the flanges on the end faces of the segments to be assembled are fastened together with bolts and nuts. There was no device that could automatically tighten bolts, and bolt tightening work was done exclusively by hand.

Therefore, recently, a bolt and a nut that were previously provided facing each other on the flange portion to be connected are engaged with each other.
An automatic bolt fastening machine has been proposed that automatically threads and fastens the bolt and nut by horizontally feeding the bolt in the direction of the nut while rotating the nut.
That is, the above-mentioned automatic bolt fastening machine has a structure as shown in FIGS. 3 to 5. In the diagram,
The case where it is applied to joining segments is shown. Flange hole 3 on the periphery of segment 1
A bolt hole 4 is formed in the flange 2 formed by providing a bolt hole 4, and a nut 5 with a grip part 5a rotatably attached to one flange 2a of the flange 2 via a pedestal 7, and a plate to the other flange 2b. A bolt 6, which is attached in advance so as to be movable in the axial direction thereof, is opposed to the bolt 6 via a holder 8 made of a spring. The bolt fastening machine connects the bolt 6 and nut 5 mentioned above.
In order to fasten the flanges 2a and 2b by engaging with the flanges 2a and 2b by axially feeding the bolt 6 while rotating the nut, a guide frame 9 is provided which is spaced apart from the flange 2 and supported parallel to the bolt 6. The guide frame 9 is provided with a bolt engaging arm 10 and a nut engaging arm 11 whose tips extend toward the flange 2 so as to be movable toward and away from each other along the guide frame 9. In the illustrated example, as shown in FIGS. 3 and 4, the guide frame 9 has four rods 12 arranged in parallel at appropriate intervals vertically and horizontally, and both ends of these rods 12 are attached to the pedestal 13. Both legs 13
a, 13b. The pedestal 13 is used to install cylinders 14 and 15, which are engaging arm moving means for moving the engaging arms 10 and 11, respectively, and has flat plate-like leg portions 13a, at both longitudinal ends.
13b is provided.

A guide hole 16 through which the rod 12 of the guide frame 9 is inserted is formed at the base end of the engaging arms 10, 11, and operating rods 10a, 11a extend upward to pass through the pedestal 13 and are integrally formed. It is set up as follows. Therefore, a guide groove 17 is formed in the pedestal 13 along the longitudinal direction to allow movement of the operating rods 10a, 11a passing through the pedestal 13. Further, each operating rod 10a, 11
The tips of piston rods 14a and 15a of cylinders 14 and 15 fixed on the pedestal 13 via brackets 18 are connected to a, and the engagement arm 1 is moved by the driving of the cylinders 14 and 15.
0 and 11 can be moved respectively.

At the opposite ends of the engagement arms 10 and 11, one end has the head 6a of the bolt 6.
A bolt engaging hole 19 is formed in the bolt engaging hole 19 to be removably engaged with the nut 5 to restrict its rotation, and a nut rotating tool 20 is provided in the other end to be removably engaged with the nut 5 in order to rotate it. ing. As shown in FIG. 5, the nut rotating tool 20 is composed of a driven gear having an external gear part 20a at the center in the width direction, and a socket part 20b for engaging the nut 5 is formed in the shaft core part. The nut engaging arm 11 to which the nut rotating tool 20 is attached constitutes a gear casing, and the nut rotating tool 20 is rotatably housed in the tip via a bearing 21. A motor 23 having a driving gear 22 fixed to a rotating shaft 21a is fixed to the base end of the nut engaging arm 11 as a rotation driving means for rotationally driving the nut rotating tool 20, and the driving gear 22 is connected to the nut engaging arm. It is rotatably supported within 11 via a bearing 24.

Further, between the drive gear 22 of the nut engaging arm 11 and the nut rotating tool 20, there is an intermediate gear 2 that meshes with both.
5 is rotatably attached via a bearing 26.

Note that one leg 13a of the pedestal 13 is provided with a motor insertion window 2 in order to avoid interference with the motor 23.
7 is formed. The other leg 13b of the pedestal 13 is a support base 28 for installing the automatic bolt tightening machine having the above structure on the erector of a shield excavator, etc.
Fixed.

When bolting is performed using an automatic bolt tightening machine having the above configuration, the entire automatic bolt tightening machine is brought close to the segment 1, and the tips of the bolt engaging arm 10 and the nut engaging arm 11 having the bolt engaging hole 19 are tightened. each flange hole 3 of segment 1
, and align the axis of the bolt engagement hole 19 with the axis of the bolt 6. Next, the bolt engaging arm 10 and the nut engaging arm 11 are attached to the respective cylinders 14 and 15.
The heads 6 of the bolts 6 are brought close to each other by the drive of the
a to the bolt engaging hole 19, and the nut 5 to the socket portion 20b of the nut rotating tool 20, respectively. In this case, the holder 8 is placed in advance so that the head 6a of the bolt 6 matches the shape of the bolt engagement hole 19.
By fixing the nut 5 and pressing the nut 5 against the nut 5 while rotating the nut rotating tool 20 at a low speed, each can be engaged with the nut 5.

Next, the drive gear 22 is driven by the motor 23,
The nut rotation 20 is rotated via the intermediate gear 25, and in this state, the cylinder 14 is driven to axially feed the bolt 6 via the bolt engagement arm 10 toward the nut 5 against the elastic force of the holder 8. . As a result, the bolt 6 approaches the rotating nut 5 and is screwed into the nut 5, thereby tightening the flanges 2a and 2b of the segment 1 with a constant tightening torque. When the bolt fastening is completed, the power to the motor 23 is turned off, and the bolt engaging arm 10 and the nut engaging arm 11 are separated from each other by the drive of the cylinders 14 and 15, and are engaged with the head 6a of the bolt 6 and the nut 5. , and then pull the entire automatic bolt fastening machine away from segment 1.

[Problem that the invention aims to solve]

As mentioned above, the automatic bolt tightening machine that has been developed recently automatically rotates the nut and moves the bolt to automatically thread the bolt and nut together, making it easy to connect flanges. The nut rotating tool 20 can be fastened with bolts.
Since the gear part 20a and the socket part 20b are integrally constructed, if the axis of the nut 5 is deviated from the axis of the socket part 21b, the socket part 21
It is possible that the nut 5 is difficult to enter in b.

Therefore, in order to further improve the performance of the recently considered automatic bolt tightening machine, the present invention improves the nut rotating tool so that even if the axis of the nut is misaligned, it can easily enter the socket. The purpose is to ensure that bolts and nuts can be automatically fastened.

[Means for solving problems]

The present invention forms a cavity that opens toward one end in the axis extension direction inside a socket rotation gear rotatably housed in a casing, and in the cavity, one end in the axis extension direction is externally fitted onto a nut. A spring is interposed between the socket rotation gear and the socket portion to bias the socket rotation gear and the socket portion away from each other in the axial direction. , and the socket part is supported by the gear by engaging the universal joint, which is engaged with the socket part so that the rotating direction is unified, with the gear so as to be able to swing freely and rotate as one unit. The configuration is as follows.

[Effect]

Since the socket part is supported by the socket part rotating gear via the universal joint, the socket part can swing via the universal joint. Therefore, when the nut pushes on the socket part, the universal joint tilts and the conical coil spring deforms, displacing the socket part so that it can fit with the nut.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

As shown in FIG. 1, there are teeth 3 on the outer periphery within the casing 30 (e.g., the nut engaging arm 11 in FIG. 3).
A gear 31 for rotating the socket part is rotatably housed via a bearing 35, and the inside is hollow and a step part 33 and a stopper 34 are provided near the rear end. The opening 36 in front of the gear 31 has a tapered part 38 on the inner periphery of the front end, and has an outer diameter larger than the inner diameter of the opening 36 so as to form a required gap between the opening 36 and the opening 36 of the gear 31. A socket portion 37 having a small dimension and having a stepped portion 39 on its outer periphery is inserted into the socket portion 37 . A conical coil spring 40 is interposed between the stepped portion 33 inside the gear 31 and the stepped portion 39 of the socket portion 37, and the socket portion 37 is normally centered by the conical coil spring 40, and the taper of the socket portion 37 is When external pressure is applied to the portion 38, the conical coil spring 40
is designed to be able to transform. Above socket part 3
One end of a universal joint 41 is engaged with the rear end of the gear 31 so that it can swing freely and rotate together, and the other end of the universal joint 41 is connected to the rear end of the gear 31. The stopper 34 inside the gear 31 is located in the recess in the middle part of the universal joint 41, and the stopper 34 between the gear 31 and the socket 37 is To be able to regulate the movement of a universal joint 41. 42 is Natsu.

In a state where the casing 30 and the nut 42 are displaced relative to each other and the socket portion 37 engages with the nut 42, if the axis of the socket portion and the axis of the nut 42 are misaligned, the taper portion 38 of the socket portion 37
corresponds to the outer diameter portion of the nut 42. If the socket portion 37 continues to move toward the nut 42 together with the casing 30, the tapered portion 38 will be pushed by the outer diameter portion of the nut 42. When the tapered portion 38 is pushed by the outer diameter portion of the nut 42, the universal joint 41 tilts as shown in FIG. 2, the conical coil spring 40 deforms, and the socket portion 37 moves in parallel. As a result, the axes of the nut 42 and the socket portion 37 are aligned, and the socket portion 37 is adapted to and engaged with the nut 42.

The nut rotating device of the present invention can be implemented as an automatic bolt fastening machine by using it in place of the nut rotating tool 20 in the automatic bolt fastening machine shown in FIGS. 3 to 5. The socket part 37 is the nut 42
When the gear 31 is rotated after being fitted, the socket portion 37 is rotated via the universal joint 41.

Note that FIGS. 3 to 5 show a case in which the nut rotating device of the present invention is applied to an automatic bolt tightening machine that tightens bolts for segment 1 as an object to be fastened. Of course, the present invention can be applied to a fastening machine used for fastening objects other than segments.

〔Effect of the invention〕

As described above, according to the nut rotating device of the present invention, since the socket portion can be displaced via the universal joint, even if the axis of the nut and the axis of the socket do not match, the nut can be rotated in the socket portion. When the bolt hits the bolt, the socket part automatically moves to fit the nut, and the socket part and the nut can be easily fitted together. Bolt fastening can be performed more reliably.

Furthermore, since the socket portion is housed inside the socket rotation gear, the axial dimension of the device can be reduced.

[Brief explanation of drawings]

Fig. 1 is a cutaway plan view of the nut rotating device of the present invention, Fig. 2 is a sectional view showing the state when the socket portion moves, and Fig. 3 is a partially cutaway side view of a recently considered automatic bolt tightening machine. 4 is a plan view of FIG. 3, and FIG. 5 is a cross-sectional view taken along line AA of FIG. 4. 5 is a nut, 6 is a bolt, 10 is a bolt engagement arm, 11 is a nut engagement arm, 30 is a casing, 3
1 is a gear for rotating the socket part, 37 is a socket part,
40 is a conical coil spring, and 41 is a universal joint.

Claims (1)

[Claims] 1. A socket portion rotatably housed in the casing. A cavity is formed inside the rotating gear and opens toward one end in the axis extension direction, and within the cavity, a socket portion whose one end in the axis extension direction can be externally fitted onto a nut is formed. a spring is interposed between the socket rotation gear and the socket portion to urge the socket rotation gear and the socket portion to move away from each other in the axial direction; Used in an automatic bolt fastening machine characterized in that a universal joint is engaged with the gear so as to be able to swing freely and rotate together with the gear. Nut rotating device.