JPH08158794A - Shield device - Google Patents

Abstract

(57) [Summary] [Purpose] To provide a shield device in which the forward direction is not easily affected by the properties of the ground that contacts the tip of the rotor. The shield device includes a tubular shield body, a shaft rotatably supported by the shield body around its axis, and a region in front of the shield body, which is rotatably supported by the shaft. A rotor and a drive mechanism for rotating the shaft about its axis of rotation. The rotor has a substantially conical outer surface and a rotation axis that intersects with the rotation axis of the shaft near the tip of the rotor so that the portion closer to the shield body is farther away from the rotation axis of the shaft in the radial direction of the shield body. Have and.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shield device used when constructing a horizontal hole, a vertical hole, a tunnel, etc. in the ground.

[0002]

2. Description of the Related Art As a shield device for constructing a tunnel or the like without excavating the ground by compacting the ground like a pile driver, a cylindrical shield main body and an axis line of the shield main body. A crankshaft rotatably supported around and having an eccentric part, and rotatably supported by the eccentric part of the crankshaft in front of the shield body,
Some include one or more rotors having a generally conical or frusto-conical outer surface and a drive mechanism for rotating the crankshaft about said axis (JP-A-59-192193).
Gazette, U.S. Pat. No. 3,926,267).

This conventional shield device is advanced by an original pushing mechanism or the like while the crankshaft is rotated. The rotor makes a revolving motion (revolutionary motion) around the rotation axis of the crankshaft as the crankshaft rotates, and at this time, revolving with the outer peripheral surface abutting against the ground causes the eccentric portion of the crankshaft to move. Rotate around the axis (rotate). As a result, the conventional shield device is advanced while consolidating the ground on the outer surface of the rotor to form a hole such as a tunnel in the ground.

However, in the conventional shield device, the rotor as a whole makes a revolving motion (revolution motion) around the rotation axis of the crankshaft, so that the advancing direction of the shield device is at the tip of the rotor (that is, at the apex of the conical shape). It is greatly affected by the property of the ground that abuts the corresponding part), and as a result, the shield device meanders greatly, and the work of correcting the forward direction must be performed frequently.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a shield device in which the forward direction is less affected by the properties of the ground contacting the tip of the rotor.

[0006]

A shield device according to the present invention is provided with a cylindrical shield body, a shaft rotatably supported by the shield body around its axis, and a region in front of the shield body. , A rotor rotatably supported on the shaft, and a drive mechanism for rotating the shaft around its rotation axis. The rotor has a substantially conical outer surface and a rotation axis that intersects with the rotation axis of the shaft near the tip of the rotor so that the portion closer to the shield body is farther away from the rotation axis of the shaft in the radial direction of the shield body. Have and.

The shield device is advanced by a former pushing device or the like while the shaft is rotated. The rotor makes a revolving motion (revolutionary motion) around the rotation axis of the shaft with the rotation of the shaft, and at the same time, the rotor makes a revolving motion with the outer peripheral surface abutting against the ground so that the rotor rotates with respect to the rotation axis of the shaft. Performs rotational movement (rotational movement) around an inclined axis of rotation. As a result, the shield device is advanced while consolidating the ground on the outer surface of the rotor to form a hole such as a tunnel in the ground.

Crossing the rotation axis of the shaft near the tip of the rotor so that the rotation axis of the most advanced rotor is separated from the rotation axis of the shaft toward the outer side in the radial direction of the shield body toward the side closer to the shield body. If the eccentricity of the rotation axis of the rotor with respect to the rotation axis of the shaft is increased, the tip of the rotor will not be largely rotated around the rotation axis of the shaft, and the rotor and the ground around it will not be rotated. There is almost no slip between them.

Therefore, according to the present invention, the forward direction of the shield device is set in spite of the fact that the rotor makes a rotational movement about the rotation axis of the shaft and a rotation movement about the rotation axis of the rotor itself. It is unlikely to be affected by the properties of the ground that contacts the tip of the rotor, and the forward direction of the shield device is stabilized.

In addition, adjacent rotors may include one or more other rotors located behind the rotor having the conical outer surface to cooperate with the rotor having the conical outer surface to form the outer surface. It is preferable to displace the rotation axes of the above-mentioned ones on the opposite sides of the rotation axis of the shaft. As a result, the ground is compacted by the adjacent rollers that are displaced in the opposite directions, so that the reaction forces that act on the adjacent rollers due to the compaction of the ground cancel each other out, and as a result, the bending moment that acts on the shield body. Becomes smaller in proportion to the decrease of the reaction force, the forward direction of the apparatus becomes more stable, and the required thrust becomes smaller.

The rotation axis of the other rotor arranged adjacent to the rotor having at least the outer surface of the conical shape is separated from the rotation axis of the shaft toward the outside in the radial direction of the shield body at a portion closer to the shield body. It is preferable to intersect the axis of rotation of the shaft near the tip of the rotor having a conical outer surface. This also causes the ground to be consolidated by the adjacent rollers that are displaced in opposite directions, so that the reaction forces that act on the adjacent rollers due to the consolidation of the ground cancel each other out, resulting in bending that acts on the shield body. The moment becomes smaller in proportion to the decrease of the reaction force, the forward direction of the device becomes more stable, and the required thrust becomes smaller.

The rotation axis of the rotor disposed next to the shield body may be an axis extending parallel to the rotation axis of the shaft.

The rotor having a conical outer surface is rotatably supported by a shaft and has a main body having a conical outer surface, and the rotor is disposed at the tip of the main body and rotates as the main body rotates. It is preferable to include a cutter portion for excavating the earth and sand in the vicinity of the axis of rotation of the shaft. As a result, since the ground near the axis of rotation of the shaft is excavated, the straightness of the shield body is improved and the required thrust is smaller than when the ground near the axis of the shield body is not excavated.

Further, it is preferable to include a mechanical seal which continuously extends around the rotation axis of the shaft and has a sealing action between the shield body and the rotor arranged next to the shield body. This allows the rotor next to the shield body to move relative to the shield body,
It is possible to prevent earth and sand from entering between the rotor and the shaft from between the shield body and the rotor adjacent to the shield body.

Further, it is preferable to include a mechanical seal that continuously extends around the shaft and performs a sealing action between adjacent rotors. Accordingly, it is possible to prevent dirt and sand from entering between the rotor and the shaft from between the adjacent rotors even though the adjacent rotors move relatively.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIGS. 1 and 2, a shield device 10 includes a cylindrical shield body 14 having an axis 12.
A shaft 16 rotatably supported by the shield body 14 around the axis 12; a conical rotor 18 arranged in a region in front of the shield body 14 and rotatably supported by the shaft 16; And a drive mechanism 20 for rotating the shaft about the axis 12.

The shield body 14 includes a first tubular portion 22.
A second tubular portion 24 partially fitted to a rear end portion of the first tubular portion 22, a wall portion 26 provided at a front end of the first tubular portion 22, and a wall portion. 26 rear surface and first tubular portion 22
A mounting portion 28 connected to the inner surface of the first and second cylindrical portions 22, which are arranged around the axis 12 at a distance.
And a plurality of hydraulic jacks 30 for connecting 24 to each other.

The mounting portion 28 has a flange portion at the front end and the rear end of the cylindrical main body portion, and cooperates with the wall portion 26 to partition the inside of the shield body 14 from the front region. Each jack 30 includes a second tubular portion 24 and a mounting portion 28.
By being connected to and, the first and second cylindrical portions 22 and 24 are connected to each other. Second tubular portion 24
The orientation of the first tubular portion 22 with respect to is modified by extending or retracting the at least one jack 30 by a predetermined amount. Thereby, the forward direction of the shield device 10 is corrected.

The shaft 16 includes a main shaft portion 32 and a main shaft portion 3.
2 has a support portion 34 successively continuing from one end, and is supported by a plurality of bearings 36 on the mounting portion 28 in the main shaft portion 32 so that the support portion 34 projects forward from the wall portion 26. The axis line 38 of the support portion 34 is inclined by an angle θ with respect to the axis line 12 so as to be farther away from the axis line 12 in the radial direction of the shield body 14 as it is farther from the tip end part of the rotor 18, and the tip end of the rotor 18 is also included. Point P0 near the part
Intersects the axis 12 at.

The rotor 18 includes a main body having a substantially conical outer surface which is rotatably supported by a support portion 34 around an axis 38 by a plurality of bearings 40, and a chisel disposed at a front end portion of the main body portion. With such a cutter portion 42, it is formed into a shape having a substantially conical outer surface. The diameter of the rear end portion of the rotor 18 is selected so that the diameter of the hole formed by the rotor 18 is substantially the same as or slightly larger than the diameter of the shield body 14. The sharp tip of the cutter portion 42 serves as the intersection P0 of the axes 12 and 38, and the rotor 1
The rotor 18 is fixed to the main body of the rotor 18 so as to rotate around the axis 38 with the rotation of 8.

The drive mechanism 20 is a known device including a rotation source such as a motor and a speed reducer connected to the rotation source, and the mounting portion 28 is formed by a plurality of bolts (not shown).
It is attached to the flange part at the rear end. Drive mechanism 2
0 is the shaft 16 by the key on the output shaft of the reducer.
Is coupled to the main shaft portion 32 of the.

The space in which the bearings 36, 40 are arranged is filled with lubricating oil. A mechanical seal 44 is provided between the wall portion 26 and the rotor 18 in order to protect the lubricating oil from the earth and sand, and an appropriate seal member (not shown) is provided as the drive mechanism 20 and the mounting portion 32. And between the wall portion 26 and the mounting portion 32.

The mechanical seal 44 is attached to the rear surface of the rotor 18 and extends around the shaft 16 in the ring 4.
6, a ring 48 disposed in a recess formed in the front surface of the wall 26 and extending around the shaft 16,
A plurality of compression coil springs 5 for pressing the ring toward the ring 46
With 0 and. The contact surfaces of the rings 46 and 48 are the ring 4
6 can be a spherical surface projecting rearward, preferably a spherical surface centered on the intersection of the axes 12 and 38. Spring 50
Are arranged in recesses formed in the wall portion 26 at equal angular intervals around the shaft 16.

Since the illustrated embodiment is a shield device used in the pipe propulsion method, the shield device 10 receives thrust from the original pushing mechanism or the like via one or more pipes 52 continuing to the rear part of the shield body 14. The pipe 52
Be advanced with. However, it is also possible to arrange a plurality of jacks between the pipe 52 arranged at the forefront and the rear portion of the shield body 14, and to advance the shield device 10 by the jacks.

The shaft 16 is rotated by the drive mechanism 20 while the shield device 10 receives thrust.
As a result, the rotor 18 makes a revolving motion (revolutionary motion) around the axis 12 with the rotation of the shaft 16, and at the same time, the rotor 18 revolves while contacting the outer peripheral surface with the ground to support the shaft 16. Rotational movement (rotational movement) about the axis 38 of 34 is performed.

As a result, the shield device 10 includes the rotor 1
8 is rotated about the axis 12 which is the axis of rotation of the shaft 16 and the axis 38 which is its axis of rotation, whereby the ground is advanced while consolidating the ground on the outer surface of the rotor 18,
As a result, holes such as tunnels are formed in the ground.

In the shield device 10, the portion where the axis 38 is closer to the shield body 14 is closer to the shield body 1 from the axis 12.
4 intersects with the axis 12 at a point P0 near the tip of the rotor 18 so as to be separated outward in the radial direction of No. 4, even when the eccentric amount of the rotor 18 with respect to the shaft 16 is increased, the shield device 10 moves forward. The tip of the cutter portion 42 does not make a large turning motion around the axis 12, and there is almost no slip between the rotor 18 and the ground around it.

Therefore, according to the shield device 10,
Even though the rotor 18 makes a turning motion about the axis 12 and a rotating motion about the axis 38, the forward direction of the shield device 10 affects the influence of the property of the ground contacting the cutter portion 42 of the rotor 18. Hard to receive and stable.

While the shield device 10 is moving forward, the mechanical seal 44 is filled with dirt and sand from the shield body 14 and the rotor 18.
It is prevented from entering between the shaft 16 and the rotor 18 from between. A ring 46 of the mechanical seal 44,
If the contact surface of 48 is a spherical surface centered on the intersection P0 of the axes 12 and 38, the rotation of the rotor 18 with respect to the shield body 14 is not hindered.

With reference to FIGS. 3 and 4, the shield device 60 includes a rotor 62 disposed between the rotor 18 and the shield body 14. The shaft 16 has a main shaft portion 32.
And a support portion 34 between the main shaft portion 32 and the support portion 34. The support 64 has an axis 66 that is displaced parallel to the axis 12 by a distance e on the side opposite the axis 38 with respect to the axis 12. The rotor 62 has a plurality of bearings 68, and an axis line 66 is attached to the support portion 64.
It is rotatably supported around.

In the shield device 60, the mechanical seal 44 is arranged between the rotors 18 and 62, and another mechanical seal 70 is arranged between the rotor 62 and the shield body 14. The ring 48 and the spring 50 of the mechanical seal 44 are arranged on the rotor 62.

The mechanical seal 70 includes a ring 72 arranged in a recess formed in the front surface of the wall portion 26 and extending around the shaft 16, and a plurality of compression coil springs 74 for pressing the ring 72 against the rear surface of the rotor 62. Equipped with. Spring 7
4 are arranged in the recesses formed in the rotor 62 around the shaft 16 at equal angular intervals. The abutment surface of the rings 46, 48 can be a spherical surface from which the ring 46 projects rearward, preferably a spherical surface centered at the intersection P0 of the axes 12, 38. On the other hand, the contact surface between the rotor 62 and the ring 72 can be a flat surface.

In the case of the shield device 60, the diameter of the rear end portion of the rotor 18 is set such that the diameter of the hole formed by the rotor 18 is substantially the same as or slightly larger than the diameter of the hole formed by the front end portion of the rotor 62. It is selected. On the other hand, the diameter of the rear end portion of the rotor 62 is selected so that the diameter of the hole formed by the rotor 62 is substantially the same as or slightly larger than the diameter of the shield body 14.

When the shaft 16 is rotated by a drive mechanism similar to the drive mechanism 20 shown in FIG. 1 while the shield device 60 is receiving thrust, the rotors 18 and 62 are
Each of the shafts 1 makes a revolving motion (revolutionary motion) around the axis 12 with the rotation of the shaft 16, and at this time, the outer peripheral surface is revolved while abutting against the ground to revolve the shaft 1.
6, the axes 34 and 66 of the supports 34 and 64
Rotate around (rotate). As a result, the shield device 60 is advanced while consolidating the ground on the outer surfaces of the rotors 18 and 62 to form a hole such as a tunnel in the ground.

Also in the shield device 60, a point near the tip of the rotor 18 is arranged so that the rotational axis 38 of the most advanced rotor 18 is located farther from the axis 12 toward the outer side in the radial direction of the shield body 14 toward the shield body 14 side. Since the axis 12 intersects with the axis 12 at P0, similar to the shield device 10, the effect due to the intersecting position of the axes 12 and 38 and the displacement direction is produced.

When the ground is consolidated, a reaction force in the radial direction of the shield body 14 is generated on the rotors 18, 62. When this reaction force is transmitted to the shield body 14 as it is, the shield body 14 is strongly pressed against the ground, so that a large frictional force is generated between the shield body 14 and the ground, and as a result, a large forward movement of the shield body 14 occurs. Requires thrust.

However, in the shield device 60, since the adjacent rotors 18 and 62 are displaced in the directions opposite to each other with respect to the axis 12, the directions of the reaction forces of the adjacent rotors 18 and 62 are opposite to each other. As a result, the reaction forces of the two adjacent rotors 18, 62 cancel each other out, so that the reaction force acting on the shield body 14 becomes small, and the frictional force between the shield body 14 and the ground due to the reaction force is reduced. As a result, the thrust required to advance the shield body 14 becomes smaller.

If the directions of the reaction forces generated in adjacent rotors are the same, this reaction force acts on the shield body as a bending moment. When such a bending moment acts on the shield body, the forward direction of the shield device becomes unstable. In particular, in the case of a device that corrects the forward direction of the shield device by correcting the direction of the second tubular part with respect to the first tubular part by the jack 30, the bending moment acting on the shield body causes the forward movement of the shield device. The direction becomes unstable, the direction correction must be frequently executed, the direction correction work becomes complicated, and the direction control becomes unstable.

However, like the shield device 60, when the reaction forces of the two adjacent rotors 18, 62 cancel each other out,
The reaction force acting on the shield body 14 as a bending moment is reduced, and the forward direction of the shield device 60 is stabilized. In addition, the forward direction of the shield device 60 is stabilized, the number of times of direction correction is reduced, the direction correction work is facilitated, and the direction control is stabilized even though the device is capable of correcting the direction.

During the forward movement of the shield device 60, the mechanical seals 44 and 70 are provided with the shaft 16 and the rotors 18 and 62 from between the rotors 18 and 62 and the shield body 14 and the rotor 62, respectively, where soil and sand are adjacent to each other.
To avoid getting in between.

Referring to FIG. 5, the shield device 80 is
It includes a frustoconical rotor 82 disposed between the rotor 18 and the shield body 14. The shaft 16 is the main shaft 3
2 and the support portion 34, and the main shaft portion 32 and the support portion 34
And a support portion 84 that integrally follows with.

The axis 86 of the support portion 84 is inclined with respect to the axis 12 on the side opposite to the axis 38 by an angle θ, and at the point P0 near the tip of the rotor 18, the axes 12, 3 are formed.
It intersects with 8. The rotor 82 is supported by a support portion 84 by a plurality of bearings 88 so as to be rotatable around an axis line 86. The angle of the axis 86 with respect to the axis 12 is
The angle may be different from the angle of the axis 38 with respect to.

In the shield device 80, the mechanical seal 44 is arranged between the rotors 18 and 82, and another mechanical seal 90 is arranged between the rotor 82 and the shield body 14. The ring 48 and the spring 50 of the mechanical seal 44 are arranged on the rotor 82.

The mechanical seal 90 is a ring 9 attached to the rear surface of the rotor 82 and extending around the shaft 16.
2, a ring 94 disposed in a recess formed in the front surface of the wall 26 and extending around the shaft 16, and a ring 94.
A plurality of compression coil springs 9 for pressing the ring toward the ring 92
6 and 6. The springs 96 are arranged in recesses formed in the wall portion 26 around the shaft 16 at equal angular intervals.
The abutting surfaces of the rings 46 and 48 and the abutting surfaces of the rings 92 and 94 are spherical surfaces on which the rings 46 and 92 project rearward, and preferably spherical surfaces centering on the intersection P0 of the axes 12, 38 and 86. be able to.

In the case of the shield device 80, the diameter of the rear end of the rotor 18 is set such that the diameter of the hole formed by the rotor 18 is substantially the same as or slightly larger than the diameter of the hole formed by the front end of the rotor 82. It is selected. On the other hand, the diameter of the rear end portion of the rotor 82 is selected so that the diameter of the hole formed by the rotor 82 is substantially the same as or slightly larger than the diameter of the shield body 14.

When the shaft 16 is rotated by a rotary mechanism of the same kind as the rotary mechanism 22 shown in FIG. 1 while the shield device 80 is receiving thrust, the rotors 18 and 82 are
Each of the shafts 1 makes a revolving motion (revolutionary motion) around the axis 12 with the rotation of the shaft 16, and at this time, the outer peripheral surface is revolved while abutting against the ground to revolve the shaft 1.
Rotational movement (rotational movement) of the supporting portions 34 and 84 of the six around the axes 38 and 86. As a result, the shield device 80 is advanced while consolidating the ground on the outer surfaces of the rotors 18 and 82 to form a hole such as a tunnel in the ground.

Also in the shield device 80, the axis 38 intersects with the axis 12 at a point P0 near the tip of the rotor 18 so that the portion closer to the shield body 14 is more distant from the axis 12 toward the outside of the shield body 14 in the radial direction. Therefore, like the shield devices 10 and 60, both axis lines 12 and 3
The action and effect caused by the intersection position of 8 and the displacement direction are produced. Further, since the adjacent rotors 18 and 82 are eccentric in the opposite directions with respect to the axis 12, similar to the shield device 60, the operational effect due to the displacement direction of the adjacent rotors is produced.

During the forward movement of the shield device 80, the mechanical seals 44 and 90 receive the shaft 16 and the rotors 18 and 82 from between the rotors 18 and 82 adjacent to each other and between the shield body 14 and the rotor 82, respectively.
To avoid getting in between.

In the embodiment of FIGS. 1 and 5, the spring 5
0 may be arranged on the rotor 18, and the ring 46 may be pressed against the ring 48 by the spring 50. In the embodiment of FIG. 3, the spring 50 may be arranged on the rotor 18 and the ring 46 may be pressed against the ring 48 by the spring 50, or the ring 72 and the spring 74 may be arranged on the rear surface of the rotor 62. The ring 72 may be pressed against the front surface of the wall portion 26. Further, in the embodiment of FIG. 5, the spring 50 may be arranged on the rotor 82 and the ring 92 may be pressed against the ring 94 by the spring 96.

The present invention can be applied not only to a shield device having one or two rotors, but also to a shield device having three or more rotors. When using three or more rotors, all rotors may cooperate with each other to form a conical or frustoconical outer surface. Instead, the rotor closest to the shield body shall be a cylindrical rotor having the same outer dimensions as the shield body, and the other rotors shall cooperate with each other to form a conical or truncated cone outer shape. As the rotor forming the surface,
May be. In either case, it is preferable to support the rotors on the shafts so that the rotation axes (rotational axes) of the adjacent rotors are on opposite sides with respect to the rotation axis of the shaft.

According to the present invention, not only the shield device for consolidating the ground around the rotor but also at least a part of the ground around the rotor is excavated, and at least a part of the ground is taken into the shield main body so that It can also be applied to a shield device that discharges to.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of a shield device of the present invention.

FIG. 2 is a left side view of the shield device shown in FIG.

FIG. 3 is a cross-sectional view showing another embodiment of the shield device of the present invention.

FIG. 4 is a left side view of the shield device shown in FIG.

FIG. 5 is a sectional view showing still another embodiment of the shield device of the present invention.

[Explanation of symbols]

 10, 60, 80 Shield device 12, 38, 66, 86 Axis 14 Shield body 16 Shaft 18, 20, 62, 82 Rotor 22 Drive mechanism 30 Direction correction jack 32 Shaft main shaft portion 34, 64, 84 Shaft support 42 Cutter 44, 70, 90 Mechanical seal P0 Axis intersection

Claims (7)

[Claims] 1. A cylindrical shield main body, a shaft rotatably supported by the shield main body around its axis, a shaft arranged in a region in front of the shield main body, and rotatably supported by the shaft. A rotor and a drive mechanism for rotating the shaft around its rotation axis. The rotor has a substantially conical outer surface and a portion closer to the shield body from the rotation axis of the shaft to the shield. A shield device having a rotation axis that intersects with the rotation axis of the shaft near the tip of the rotor so as to be separated from the main body in the radial direction. 2. Further comprising one or more other rotors located behind said rotor having said conical outer surface to cooperate with said rotor having said conical outer surface to form an outer surface, The shield device according to claim 1, wherein the rotation axes of the adjacent rotors are displaced from each other with respect to the rotation axis of the shaft. 3. The rotation axis of the other rotor arranged adjacent to the rotor having at least the conical outer surface is located closer to the shield body in the radial direction of the shield body from the rotation axis of the shaft. The shield device according to claim 2, wherein the shield device intersects with a rotation axis of the shaft near a tip portion of the rotor having the conical outer surface so as to be separated outward. 4. The shield device according to claim 2, wherein a rotation axis of a rotor arranged next to the shield body extends parallel to a rotation axis of the shaft. 5. A rotor having a conical outer surface,
A main body that is rotatably supported by the shaft and has a conical outer surface, and a cutter that is arranged at the tip of the main body and excavates the sand near the axis of rotation of the shaft as the main body rotates. Parts, and
Or the shield device according to 4. 6. A mechanical seal, which further comprises a mechanical seal that extends continuously around the axis of rotation of the shaft and acts as a seal between the shield body and a rotor disposed adjacent to the shield body. The shield device according to any one of 1. 7. The shield device according to claim 6, further comprising a mechanical seal that continuously extends around the shaft and acts as a seal between adjacent rotors.