GB2178459A - Shield tunnelling machine - Google Patents

Abstract

A shield tunnelling machine comprises a cylindrical shield frame 1, a rotary annulus 2 mounted to rotate within the shield frame, and a lifting beam 7 which is mounted on the rotary annulus to be movable radially with respect to it. Connected to the beam 7 is a base balancer 12 which may be moved in the axial direction and connected to the base balancer by means of a ball and socket joint 16 is an end balancer 17. Attitude-adjustment cylinders are connected to the base and end balancers to move the latter in the axial and circumferential directions, that is to say, to rotate it about two perpendicular axes. A segment holding member 23 extends outwardly from the end balancer and is adapted to hold a tunnel wall segment. <IMAGE>

Description

SPECIFICATION Shield Tunnelling Machine The present invention relates to a shield tunnelling machine and is concerned with controlling the attitude of tunnel segments to enable the segments to be easily and quickly assembled.

When using a shield tunnelling machine a tunnel is formed by the machine and a wall is assembled within the tunnel in annular sections comprising a plurality of arcuate segments which are assembled one by one.

The shield tunnelling machine is generally provided with a device such as an erector arm, for erecting the segments, each of which may weigh more than one tonne. A typical segment assembling device is shown diagrammatically in Figure 1 and comprises a circular revolving annulus b mounted within a shield frame a such that the revolving annulus b can freely rotate around the inner surface of the shield frame a, a lifting beam c mounted on the revolving annulus b to be movable in the radial direction and a segment holding mechanism d which is mounted on the lifting beam c and is, in general, axially movable.

The tunnelling machine can thus move a segment which is held by the segment holding mechanism d to a desired position on the inner surface of the tunnel by rotation of the revolving annul us b and movement of the lifting beam c.

Whilst conventional shield tunnelling machines can move a wall segment in the circumferential, radial and axial directions with respect to the shield frame they cannot adjust the attitude or orientation of a segment to facilitate assembly of the segment with a partially assembled ring of segments. Therefore, if a segment which has been moved to the partially assembled ring is inclined at an angle with respect to its desired orientation to the partially assembled ring, it is necessary for operators manually to effect a fine adjustment. This can render the assembly of a segment very difficult and timeconsuming. The assembled segments are conventionally manually linked by bolts which further complicates their assembly. The handling and assembly of the heavy segments must of necessity be effected in a narrow tunnel and this requires a substantial labour force and is dangerous.

This is an important factor which contributes to the high cost of tunnel construction.

It is the object of the present invention to overcome the above and other problems encountered with conventional shield tunnelling machines and in par titular to provide a shield tunnelling machine which can suitably adjust the attitude or posture of a segment and can automatically link a segment to the partially assembled ring of segments, whereby the erection and assembly of segments can be accomplished easily and quickly and the tunnel construction costs can be reduced.

According to the present invention a shield tunnelling machine comprises a shield frame, a rotary annulus mounted to rotate within the shield frame, a lifting beam mounted on the rotary annulus to move radially with respect to the latter, balancer means connected to the lifting beam by a ball and socket joint attitudeadjustment means connected to the balancer means and arranged to rotate the latter in the axial and circumferential directions and segment holding means extending outwardly from the balancing means for releasably holding a tunnel wall segment.

The balancer means is preferably movable with respect to the rotary annulus in the axial direction. In the preferred embodiment the balancer means comprises a base balancer which is connected to actuating means to be moved thereby in the axial direction and an end balancer connected to the base balancer by the ball and socket joint.

The machine preferably includes bolt tightening means connected to the balancer means and adapted to tighten bolts to connect a tunnel wall segment to a further such segment in position in the tunnel. It is preferred that the bolt tightening means includes two arms whose ends are adapted to be inserted into adjacent apertures in adjacent tunnel wall segments, which apertures are spaced from respective side surfaces of the segments by respective flanges in which cooperating holes are formed, the two arms being movable towards and away from each other and carrying means for engaging the head of a bolt extending through the holes and means for engaging a nut, respectively, which nut may be positionally located with respect to one of the flanges but capable of rotation with respect thereto, drive means for rotating the means for engaging the nut and means for causing relative movement of the two arms.

It is preferred that the machine includes guide rollers positioned to guide a tunnel wall segment, e.g. from the rear of the machine, onto the holding member.

Further features, details and advantages of the invention will be apparent from the following description of certain specific embodiments which is given by way of example with reference to Figures 2 to 12 of the accompanying drawings, in which: Figure 2 is a rear view of a first embodiment of a shield tunnelling machine in accordance with the present invention; Figure 3 is a sectional view on the line Ill-Ill in Figure 2; Figure 4 is a sectional view on an enlarged scale of a ball and socket joint interconnecting a root balancer and an end balancer of the shield tunnelling machine shown in Figure 2; Figure 5 is a perspective view of a wall segment to be handled by a shield tunnelling machine in accordance with the present invention; Figure 6 is a scrap view showing the relationship between an engaging hole of the wall segment and a holding member;; Figure 7 is a side view of a device for tightening bolts linking adjacent segments; Figure 8 is a rear view of a second embodiment of a shield tunnelling machine in accordance with the present invention from which the balancer means and the attitude adjustment cylinders have been omitted for the sake of clarity; Figure 9 is a longitudinal sectional view of the embodiment of Figure 8; Figure 10 is a side view of a second embodiment of a device for tightening bolts linking adjacent segments; Figure 11 is a sectional view on the line Xl-Xl in Figure 10, and Figure 12 is a sectional view on an enlarged scale on the line XII-XII in Figure 11.

The same reference numerals are used throughout the drawings to designate the same components.

The shield tunnelling machine shown in Figures 2 and 3 has a cylindrical shield frame 1 forming an outer shell of the machine and a circular revolving annulus 2 disposed within the frame 1 and freely rotatably supported by it by supporting rollers 3. A gear 4 is mounted coaxially on the front surface of the annulus 2 and meshes with a pinion 5 which in turn is carried by the drive shaft on a motor M, mounted on a bracket 6 connected to the shield frame 1.

An inverted arch-shaped lifting beam 7 is disposed at the rear side of the shield frame 1 and is movable in the radial direction by means of two guide rods 8 and associated supporting arms 9 connected to the annulus 2. The guide rods 8 extend vertically upwards from respective ends of the lifting beam 7 and are slidably fitted into guide holes 10 in the supporting arms 9. Expansion cylinders 11 are disposed between the supporting arms 9 and the lifting beam 7 to effect radial movement of the lifting beam 7.

Connected to the beam 7 is balancer means comprising a base or root balancer 12 and an end balancer 17. The base balancer 12 which is of arcuate form and is slightly smaller than the lifting beam 7 is mounted on the lifting beam 7 such that the base balancer 1 2 can slide in the axial direction of the shield frame 1 along a pair of guide bars 13. The base balancer 12 is of U-shaped cross-section and the guide bars 13 are attached to the base balancer 12 and slidably fitted into guide holes 14 of the lifting beam 7.

A sliding cylinder 15 is mounted on the lifting beam 7 to slide the base balancer 12 in the axial direction.

The end balancer 17 is disposed outwardly of the base balancer 12 and is connected thereto by a ball and socket connection 16. As best seen in Figure 4, the connection 16 comprises a shaft 20 which is supported horizontally by brackets 18 depending from the base balancer 12 and has a partially spherical head portion or inner race 19, and an outer race 21 which has a partially spherical recess which slidably receives the inner race 19. The outer race 21 is securely attached to the inner surface of the end balancer 17.

The end balancer 17 is movable about the ball and socket bearing 16 in the axial direction of the shield frame 1 (this movement will be referred to as "pitching" in this specification) and is also movable in the circumferential direction of the shield frame 1 (this movement will be referred to as "rolling" in this specification) so that the attitude of the end balancer 17 may be adjusted. To this end, two attitudeadjustment cylinders 22 are connected between the base balancer 12 and the end balancer 17 and are horizontally spaced outwardly from the ball and socket connection 16 by a distance L1. When both cylinders 22 are extended or retracted, the end balancer 17 is caused to pitch, but when the cylinders 22 are alternately extended or retracted, the end balancer 17 is caused to roll.

A holding member 23 which is adapted to releasably hold a wall segment S extends downwardly from the centre of the outer surfaceof the end balancer 17. The segment holding member 23 comprises a rotary shaft 24, which extends radially outwardly from the end balancer 17, and a T-shaped hook portion formed at the leading end of the shaft 24. In use, the holding member 23 is received in an engaging hole 26 at the centre of the inner surface of the segment S.As best seen in Figures 5 and 6, the hole 26 is similar to a keyhole whereby after insertion of the holding member 23 into the hole 26 it is engaged with the segment S when the rotary shaft 24 is rotated through 90 and is disengaged when the rotary shaft 24 is rotated back through 90 . In order to effect an automatic engagement with and disengagement from the engaging hole 26, the rotary shaft 24 is connected to a motor (not shown).

Mounted on the end balancer 17 are a plurality of support jacks 27 which are adapted to extend beyond the outer surface of the end balancer 17 and to engage the inner surface of the segment S, whereby the segment S which is held by the holding member 23 is further securely maintained in the desired position.

The end balancer 17 is further provided with a plurality of devices 28 for tightening bolts which are used to link the segment S to a further such segment 0 which has been already erected or assembled.

Referring next to Figure 5, the segment S is formed with a plurality of bolt-linkage flanges 29 on the peripheral surfaces thereof and a plurality of associated flange holes 30 which are open at the inner surface of the segment S and are spaced apart by a suitable distance. A bolt hole 31 is formed through each flange 29. In order to simplify the insertion of bolts 34 and nuts 32 into the bolt holes 31, the flanged nut 32 is rotatably mounted on one (29a) of the flanges to be joined with its flange portion 32a being engaged by a flange shoe 33 on the flange 29a while the bolt 34 is inserted into the flange hole 30 in the other flange 29b and is supported by a bolt supporting means 35 comprising leaf springs such that the tip of the bolt 34 is in line with the bolt hole 31 of the flange 29b (see Figure 7).It is preferably that the nut 32 is attached to the flange 29a of the erected segment 0 in the manner described above to produce the desired relationship with the bolt-tightening device 28.

Each of the bolt-tightening devices 28 has an arm 36 adapted to be inserted into one flange hole 30 to engage with the head 34a of the bolt 34 to push the bolt 34 towards the nut 32 for engagement therewith against the spring force of the bolt supporting means 35 and a nut arm 37 adapted to be inserted into the other flange hole 30 to engage and rotate the nut 32.

A guide bar 38 which extends horizontally from the upper end of the nut arm 37 is slidably received in a guide hole formed in the upper end of the bolt arm 36 so that the bolt arm 36 is slidable along the guide bar 38. A jack 39 is mounted on the upper end of the nut arm 37 to move the bolt arm 36 toward or away from the nut arm 37. A rotary socket 40 which is adapted to engage the nut 32 to rotate the same is rotatably attached to the lower portion of the nut arm 37. A motor M2 is mounted on the upper portion of the nut arm 37 and an endless chain 43 passes around a sprocket wheel 41 carried by the drive shaft of the motor M2 and a sprocket 42 attached to the rotary socket 40 so that on energisation of the motor M2 the rotary socket 40 is rotated.Such bolt-tightening devices 28 are disposed on the end balancer 17 at positions corresponding to those of the flange holes 30 of the segments S and 0. The right hand end of the guide bar 38 (as seen in Figure 7) is connected to a jack 44 mounted on the end balancer 17 so that when the jack 44 is extended or retracted, the rotary socket 40 is moved away from or toward the nut 32.

The mode of operation of the first embodiment described above is as follows: Firstly, the end balancer 17 is moved toward the segment S with its engaging hole 26 facing upwards and the segment holding member or hook 23 is inserted into the engaging hole 26 of the segment S and is rotated through 90 to engage it firmly with the segment S. Then the segment S is lifted and the supporting jacks 27 are extended and pressed against the inner surface of the segment S so that the segment S is securely held in position. The segment S is moved to the desired position relative to the erected segment O by rotating the revolving annulus 2, moving the lifting beam 7 in the radial direction and moving the base balancer 12 in the axial direction.It may of course occur that the segment S is not correctly brought to the predetermined position or the transferred segment S is not correctly aligned with the erected segment 0. In this case, a misalignment in the axial or X direction (see Figure 5) is eliminated by movement in the axial direction of the base balancer 12 by actuation of the cylinder 15 while a misalignment in the circumferential or Y direction is eliminated by rotation of the revolving annulus 2. A misalignment in the radial or Z direction is eliminated by radial movement of the lifting beam 7 by actuation of the cylinder 11. Furthermore, an angular misalignment about the X-axis is eliminated by extending one of the posture-adjustment cylinders 22 while retracting the other cylinder 22.An angular misalignment about the Y-axis is eliminated by causing both the postureadjustment cylinders 22 to extend or retract simultaneously. A misalignment about the Z-axis is eliminated when the segment S abuts against the erected segment 0 because the segment S is caused to rotate about the ball and socket joint. Thus the posture of the segment S can be readily suitably adjusted so that the erection of the segment S can be easily and quickly accomplished.

After the segment S has been brought to the predetermined position and correctly aligned with the erected segment 0 in the manner described above, the segments S and 0 are linked with each other by bolts 34 and nuts 33. The bolt arm 36 and the nut arm 37 of the bolt-tightening device 28 are inserted into the flange holes 30 of the segments S and 0. The jacks 39 and 44 are retracted so that the rotary socket 40 is brought into engagement with the nut 32 and the bolt arm 36 is brought into engagement with the head 34a and the bolt 34. Thereafter the nut 32 is then rotated by the motor M2 while the bolt 34 is pushed toward the nut 32 by the bolt arm 36 which is caused to move to the left (in Figure 7) by the jack 39 which is retracted. Alternatively, pushing of the bolt 34 toward the mating nut 32 may be stopped when they engage each other.Thus the linking of the segments S and 0 together by bolts can be accomplished easily, safely and quickly without the need of any manual operative.

A second embodiment of a shield tunnelling machine in accordance with the present invention will now be described with reference to Figures 8 and 9 in which a segment S is illustrated being secured at the top portion of a tunnel. As in the first embodiment, the supporting arms 9 extend inwardly from the revolving annulus 2 and the lifting beam 7 is movable in the radial direction along the guide rods 8. Cylinders 11 are connected between the lifting beam 7 and the supporting arms 9 to move the former. However, the segment holding member 23 which comprises the rotary shaft 24 and the hook 25 at the leading end thereof, is directly attached to the lifting beam 7.When the segment holding member 23 is inserted into the engaging hole 26 at the centre of the inner surface of the segment S and is rotated, the segment holding member 23 is firmly engaged with the segment S, as shown in Figure 6. In order to insert, rotate and release the segment holding member 23 into, in and from the engaging hole 26, a cylinder 45 is connected to the lower end of the rotary shaft 24 and a cylinder 47 is connected to a lever 46 which is in spline engagement with the rotary shaft 24, whereby the lever 46 may slide in the axial direction of the rotary shaft 24.

The segment S whose inner surface is directed downwardly is transferred towards the lifting beam 7 with the segment holding member 23 directed upwardly, and guided towards the segment holding member 23 by guide rollers 48 which are rotatably attached to the upper ends of brackets 49 extending upwardly from the side surfaces of the lifting beam 7.

A plurality of guide rollers 48 is provided in the circumferential and axial directions of the tunnel so that they support the inner surface of the segment S and guide it in a stabilised manner. An abutment 50 is disposed at the rear end of the lifting beam 7 so that when the segment S guided by the guide rollers 48 engages the abutment 50, the engaging hole 26 of the segment S is in line with the rotary shaft 24 of the segment holding member 23.

A segment supply device 51 is provided which includes a pusher 52 disposed at the upper portion of the tunnel and adapted to push the segment S toward the lifting beam 7, a conveyor system 53 disposed rearwardly of the pusher 52 for supplying a segment S onto the pusher 52 and a pantograph type lifter 55 adapted to lift a segment S carried by a carriage 54 to the level of the conveyor system 53.

The second embodiment includes an end balancer and a base balancer of the type described above but as mentioned above, these have not been illustrated for the sake of simplicity. However, items 47 and 48 in Figure 9 replace item 27 in Figure 3.

The mode of operation of the second embodiment is as follows: The revolving annulus 2 is rotated so that the lifting beam 7 is brought to its uppermost position, as shown in Figures 8 and 9. When the pusher 52 of the segment supply device 51 advances a segment S, the segment S is then supported by the guide rollers 48 and guided over the lifting beam 7 and stopped at a predetermined position when the leading end of the segment S engages the abutment 50. The cylinder 45 is then energised so that the rotary shaft 24 is raised and inserted into the engaging hole 26 in the segment S. The rotary cylinder 47 is energised so that the lever 46 is moved and consequently the rotary shaft 24 is rotated through 90 , whereby the hook 25 engages in the engaging hole 26 in the manner described above.

The cylinder 45 is retracted so that the inner surface of the segment S is pressed against the guide rollers 48 so that the segment S is now securely held in position.

Then the revolving annulus 2 is rotated and the lifting beam 7 is moved in the radial direction so that the segment S is brought to a predetermined position in the tunnel and is connected to the segments which have been already erected and assembled in the form of a partially completed ring.

Figures 10 to 12 show another embodiment of the bolt-tightening device. This device includes a guide frame 56 extending in parallel to the bolt 34 and spaced above the flanges 29 by a suitable distance.

The guide frame 56 is slidably received in holes in the bolt arm 36 and the nut arm 37 so that the arms 36 and 37 can move toward or away from each other. The guide frame 56 comprises four parallel rods 57 spaced apart from each other in the vertical and horizontal directions by a suitable distance whose ends are attached to the leg portions 58a and 58b, respectively, of a mount or stand 58 upon which cylinders 59 and 60 are mounted for moving the arms 36 and 37, respectively. The leg portions 58a and 58b extend downwardly from the ends of the stand 58.

The arms 36 and 37 are formed with guide holes 61 which slidably receive the rods 57 and actuating rods 36a and 37a extend upwardly through the stand 58 from the upper ends of the arms 36 and 37 respectively. In order to permit movement of the actuating rods 36a and 37a in the longitudinal direction of the stand 58, a longitudinally elongated guide slot 62 is formed in the stand 58. The actuating rods 36a and 37a are connected to the piston rods 59a and 60a, respectively, of the cylinders 59 and 60 which are mounted on the stand 58 by brackets 63 so that when the piston rods 59a and 60a are extended or retracted, the actuating rods 36a and 37a are moved in the longitudinal direction of the stand 58.

A bolt-engagement hole 64 which is adapted to releasably engage the head 34a of the bolt 34 is formed in the lower end of the bolt arm 36 which is opposed to the lower end of the nut arm 37. A socket 40 which is adapted to releasably engage with the nut 32 and to rotate the same is provided at the lower end of the nut arm 37 facing the bolt arm 36. As best seen in Figure 12, the nut socket 40 comprises a driven gear with gear teeth 40a disposed between the outer and inner surfaces of the nut arm 37 adjacent the lower end thereof. An engaging hole 40b for engagement with the nut 32 is formed on the axis of the gear. The nut arm 37 is in the form of a gear casing and the nut socket 40 is rotatably mounted by bearings 65 in the lower portion of the nut arm 37.A motor 66 is securely mounted on the outer surface of the nut arm 37 adjacent to the upper end thereof and a driving gear 67 is carried by the drive shaft 66a of the motor 66 and is rotatably carried by bearings 68 in the upper portion of the nut arm 37. The driving gear 67 is drivingly coupled to the nut socket 40 by an intermediate gear 69 which is rotatably carried by bearings 70 between the driving gear 67 and the nut socket 40.

The leg portion 58a of the stand 58 is formed with a motor opening 71 through which the motor 66 passes.

The leg portion 58b of the stand 58 is securely attached to the end balancer 17.

The mode of operation of the second embodiment of the bolt-tightening device is as follows: The bolttightening device 28 is moved toward the segment S so that the bolt arm 36 and the nut arm 37 are inserted into the flange holes 30, as best shown in Figure 10 such that the bolt-engagement hole 64 of the bolt arm 36 is in line with the bolt 34. The piston rods 59a and 60a of the cylinders 59 and 60 are extended so that the arms 36 and 37 are moved towards each other and the head 34a of the bolt 34 is received in the bolt-engagement hole 64 while the nut is received in the hole 40b of the nut socket 40. In this case, the bolt 34 is supported by the bolt supporting means 35 such that the head 34a of the bolt 34 snugly fits in the bolt-engagement hole 64 of the bolt arm 37.When the nut socket 40 is rotated at a slow speed and pushed toward the nut 32 it can be easily engaged with the nut 32.

Thereafter, the motor 66 is energised so that the nut socket 40 is rotated by the driving gear 67 and the intermediate gear 69 and the piston rod 59a of the cylinder 50 is extended so that the bolt 34 is moved toward the nut 32 in the axial direction of the bolt 34 against the force of the bolt supporting means 35. The bolt 34 is thus threadably engaged with the nut 32 and consequently the adjacent segments S are linked together by the bolts 34 and nuts 32 which are tightened to a suitable torque.After the bolt 34 and the nut 32 have been engaged with each other in the manner described above, the motor 66 is de-energised and the piston rods 59a and 60a of the cylinders 59 and 60 are retracted so that the arms 36 and 37 are moved away from each other and the head 34a of the bolt 34 is released from the bolt-engagement hole 64 of the bolt arm 36 while the nut 32 is released from the nut socket 40 of the nut arm 37.

As described above, the bolts 34 which link adjacent segments S together can be automatically and mechanically tightened even under confined conditions where it is very difficult to tighten the bolts by hand.

The automatic bolt-tightening device has been described as being used to link adjacent tunnel segments together but it will be understood that it may also be used to automatically tighten bolts in a narrow space to link any parts together.

The effects, features and advantages of the shield tunnelling machine in accordance with the present invention may be summarised as follows: The base balancer is mounted on the lifting beam to be movable in the axial direction and the end balancer which is adapted to hold a segment is connected to the base balancer by a ball and socket joint so that the end balancer may swing about the ball and socket joint in the circumferential and axial directions when the posture-adjustment cylinders are actuated. The end balancer can thus suitably control the posture of the segment and the erection and assembly of segments can be accomplished easily and quickly and the tunnel construction costs can be minimised. The end balancer is provided with one or more bolt-tightening devices so that adjacent segments can be automatically linked together while the posture of the segment held by the end balancer is suitably controlled. Therefore, the erection and assembly of segments is facilitated and the number of workers required for this purpose can be decreased and their safety improved. If a sensor for detecting the position of a segment which has been already erected is provided so that a segment which is supplied from the rear of the shield can be guided toward the segment holding member smoothly and quickly. The construction of the shield tunnelling machine of the present invention is simple so that such tunnelling machines can be fabricated easily and the present invention can be easily applied to existing machines.

Claims (7)

1. A shield tunnelling machine comprising a shield frame, a rotary annulus mounted to rotate within the shield frame, a lifting beam mounted on the rotary annulus to move radially with respect to the latter, balancer means connected to the lifting beam by a ball and socket joint, attitude-adjustment means connected to the balancer means and arranged to rotate the latter in the axial and circumferential directions and segment holding means extending outwardly from the balancing means for releasably holding a tunnel wall segment.

2. A machine as claimed in claim 1 in which the balancer means is movable with respect to the rotary annulus in the axial direction.

3. A machine as claimed in claim 2 in which the balancer means comprises a base balancer which is connected to actuating means to be moved thereby in the axial direction and an end balancer connected to the base balancer by the ball and socket joint.

4. A machine as claimed in any one of the preceding claims including bolt-tightening means connected to the balancer means and adapted to tighten the bolts to connect a tunnel wall segment to a further such segment in position in the tunnel.

5. A machine as claimed in claim 4 in which the bolt-tightening means includes two arms whose ends are adapted to be inserted into adjacent apertures in adjacent tunnel wall segments, which apertures are spaced from respective side surfaces of the segments by respective flanges in which cooperating holes are formed, the two arms being movable towards and away from each other and carrying means for engaging the head of a bolt extending through the holes and means for engaging a nut, respectively, drive means for rotating the means for engaging the nut and means for causing relative movement of the two arms.

6. A machine as claimed in any one of the preceding claims including guide rollers positioned to guide a tunnel wall segment onto the holding member.

7. A shield tunnelling machine substantially as specifically herein described with reference to Figures 2 to 4 or Figures 8 to 9, optionally in conjunction with Figure 7 or Figures 10 to 12.