JPH0370079B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field of the Invention) The present invention generally relates to a shield tunnel propulsion device, and more particularly to a shield propulsion device suitable for use in a pipe propulsion method.

(Prior art) In the pipe propulsion method, a shield is generally installed at the forefront of the pipe to be propelled, and the ground is perforated by the operation of a cutter provided on the shield, followed by the operation of a jack at the rear of the pipe. exerts a thrust on the shield and tube, propelling them both into the drilled ground. The cutters are spaced apart in front of a diametrical bulkhead inside the shield, and when the shield and tube are being propelled, the excavated material scraped by the cutters falls within the space. The excavated material is kept in a full state, and the reaction force from the bulkhead acts on the ground face. This reaction force and earth pressure are balanced and the face is maintained stably.

(Problem to be Solved by the Invention) Conventionally, the excavated material rotates within the above-mentioned interval as the cutter rotates, and reaches a discharge means such as a screw conveyor provided at the bottom of the partition wall, and is discharged through this discharge means. has been done. Therefore, a large frictional force acts between the excavated object and the partition wall, increasing the load on the cutter drive device.

In view of the above, a shield propulsion method has been proposed in which a consolidation head provided in the front space of the shield body is rotated eccentrically and rotated on its own axis, and a thrust is exerted on the shield body during the eccentric rotation of the consolidation head ( Patent Application No. 70770, 1982;
Publication No. 215996). According to this shield propulsion method,
The material to be excavated is not guided to the discharge port while rotating inside the shield body, but is guided straight to the discharge port by compaction of the material to be excavated in the radial direction and reaction force of earth pressure. Frictional force can be significantly reduced.

An object of the present invention is to provide a shield propulsion device that implements the shield propulsion method described above.

Another object of the present invention is to provide a shield propulsion device that can be used on a wide range of ground, from soft ground to hard ground.

(Means for Solving the Problems) The shield propulsion device according to the present invention includes a cylindrical shield main body, a partition wall provided in the diametrical direction of the main body, and a partition wall provided in front of the partition wall, and an inner peripheral surface of the shield main body. a shield body having an enclosed space, the diameter of the inner circumferential surface of which gradually decreases toward the rear, defining the space having a truncated conical shape; and an axis extending from the rear of the partition wall to the front thereof; a rotatable consolidation head disposed surrounding the shaft in the space, the consolidation head having its axis offset from the axis of the shaft; and a drive mechanism for eccentrically rotating the consolidation head with respect to the shaft; means for discharging excavated material from the front area of the bulkhead to the rear area thereof;
and a jack that is located behind the shield body and applies thrust to the shield body.

Instead of the truncated cone-shaped space, the shield body may also be implemented by providing a cylindrical space in the front part, the diameter of which is substantially the same as that of the inner peripheral surface of the shield body in the axial direction. Ru.

In one embodiment, the drive mechanism includes an eccentric sleeve disposed between the shaft and the consolidation head and fixed to the shaft, which rotatably supports the consolidation head, and the partition wall. and a drive source connected to the shaft at the rear of the shaft.

In another embodiment, the drive mechanism includes an eccentric sleeve disposed between the shaft and the consolidation head and fixed to the shaft, which rotatably supports the consolidation head, and the partition wall. a drive source connected to the shaft at the rear of the consolidation head; a first gear provided on the consolidation head; and a second gear meshing with the first gear.

In yet another embodiment, the drive mechanism is an eccentric sleeve disposed between the shaft and the consolidation head and rotatably supported on the shaft, the eccentric sleeve rotatably supporting the consolidation head. a drive source connected to the shaft behind the bulkhead; a first gear provided on the consolidation head;
and a second gear provided on the shaft to mesh with the first gear.

In yet another embodiment, the drive mechanism is an eccentric sleeve rotatably supported on the shaft, the eccentric portion being disposed between the shaft and the consolidation head and rotatably supporting the consolidation head. and a shaft portion extending rearward from the eccentric portion and protruding rearwardly through between the partition wall and the shaft, and connected to the shaft portion of the eccentric sleeve at the rear of the partition wall. The device includes a first drive source and a second drive source connected to the shaft behind the partition wall.

If the propulsion device is used for shield propulsion in soft ground, there is no need to provide a cutter in the consolidation head. If the propulsion device is used for shield propulsion in hard ground, the cutter is attached to the consolidation head.

(Example) As shown in FIG. 1, the shield propulsion device 10 is a cylindrical shield main body 12, and has a partition wall 20 provided in the diametrical direction thereof and a space 14 provided in front of the partition wall 20. A shield body 12,
Conical consolidation head 1 arranged in space 14
6, and a jack (not shown), which is known per se and which exerts a thrust force on a concrete pipe connected to the rear of the shield body 12.

The space 14 is surrounded by the inner peripheral surface 18 of the shield body 12. The inner circumferential surface 18 is formed into a truncated conical shape whose diameter gradually decreases toward the rear, and defines a truncated conical space 14 .

The shaft 22 is straight and extends from the rear of the bulkhead 20 to the front thereof. In the illustrated embodiment, shaft 22
is arranged within the shield body 12 with its axis aligned with the axis of the shield body 12, and includes a rolling bearing 24 mounted on the partition wall 20, and a plurality of ribs 26 provided on the shield body 12 in front of the inner circumferential surface 18.
The shaft 22 is rotatably supported by a rolling bearing 28 mounted on a bearing part 27 of the shaft 22.
Both sides are supported at the front and back of 4. According to this configuration, the diameter of the shaft 22 can be reduced, and the outer diameter of the shield body 12 can be reduced, compared to the case where the shaft 22 is cantilevered forward from the partition wall 20.

A consolidation head 16 is disposed with its axis offset from the axis of the shaft 22 by an amount e, surrounding the portion of the shaft 22 located in the space 14 surrounded by the inner circumferential surface 18. A drive mechanism 30 is provided for eccentric rotational movement about the shaft 22.

The drive mechanism 30 includes an eccentric sleeve 32 and a drive source 34
Equipped with. The eccentric sleeve 32 has a circular outer shape, and a hole 33 having an axis is bored in the eccentric sleeve 32 at a position offset by e from the center of the circle. The eccentric sleeve 32 is press-fitted onto the shaft 22 and fixed thereto. In addition, the eccentric sleeve 32 may be formed integrally with the shaft 22. In this specification, when the eccentric sleeve 32 is fixed to the shaft 22, it means that the eccentric sleeve 32 is formed separately from the shaft 22 and then attached to the shaft 22 by press fitting or the like. Including cases where it is formed integrally. Eccentric sleeve 32
Rolling bearings 36 and 38 are installed at the front and rear ends of the
The consolidation head 16 is rotatably supported by the eccentric sleeve 32 via these rolling bearings 36 and 38.

The drive source 34 includes a gear 40 fixed to the shaft 22 behind the partition wall 20 by a key 39, and an electric motor 42.
and a gear 44 that is fixed to the output shaft of the electric motor 42 by a key 43 and meshes with the gear 40.
The electric motor 42 is connected to the casing 4 provided on the bulkhead 20.
6, and the rear end of the shaft 22 is supported by a pair of rolling bearings 48 mounted on a casing 46.

A pair of pipes 50 and 52 are attached to the lower part of the partition wall 20 at intervals in the circumferential direction, and both of these pipes are opened toward the front of the partition wall, and there is a gap between the inner circumferential surface 18 and the partition wall 20. It communicates with a sitting room 54. The pipe 50 is a liquid supply pipe for supplying liquid such as fresh water or muddy water to the front of the partition wall 20, and the pipe 52 is a liquid supply pipe for supplying liquid such as fresh water or muddy water to the front of the partition wall 20, and the pipe 52 is for supplying excavated materials such as surplus water and earth and sand in the ground together with the supplied liquid. This is a liquid discharge pipe for discharging the liquid. In addition to this, the material to be excavated can also be discharged using a screw conveyor.

Shaft 22 includes a cutter 56 mounted forward of consolidation head 16. In the illustrated embodiment, the cutter 56 includes a plurality of spokes 59 extending radially from a boss 58 fixed to the shaft 22 by a key 57;
It consists of a plurality of bits or chips 60 provided on each spoke. Alternatively, the cutter 56 may be constructed of a disk having at least one slit, with a plurality of bits or tips protruding forward from the slit. Katsuta 56
can be omitted when the propulsion device 10 is propelled through soft or soft ground.

In the illustrated propulsion device 10, in order to enhance the crushing action of the consolidation head 16, a plurality of convex portions 62 and 63 are provided on the inner peripheral surface 18 of the shield body 12 and the peripheral surface 17 of the consolidation head 16, respectively, and extend in the circumferential direction. It is provided. These protrusions can also be radial.

In addition, in the illustrated propulsion device 10, the consolidation head 1
6 and a portion of the partition wall 20 near the bearing 24, a sealing device 64 is provided to seal the gap between the consolidation head 16 and the bearing portion 27 of the rib 26. This sealing device 64 includes a ring 66 and a spring 68. In the sealing device 64 on the side of the bulkhead 20, a ring 66 is disposed in a forward-facing hole in the bulkhead 20 so as to be movable in the axial direction of the shaft 22 and is biased forwardly by a spring 68 so that the consolidation head 16 It is pressed against a cover 70 attached to. Further, in the sealing device 64 on the side of the bearing portion 27,
A ring 66 is disposed axially movably in a rearwardly facing bore of the bearing 27 and is biased rearwardly by a spring 68 and pressed against the consolidation head 16. According to this sealing device 64, the ring 66 and/or the consolidation head 16
When the sliding part of the ring 66 wears out, the ring 66 is pushed toward the consolidation head 16 by the spring 68, so that it always comes into close contact with the consolidation head, and a permanent sealing performance can be obtained.

In the illustrated embodiment, a conical consolidation head 16 whose outer diameter gradually increases toward the rear is located within a truncated conical space 14 surrounded by an inner circumferential surface 18 whose diameter gradually decreases toward the rear. It is located.
In addition to this, the combination of the space of the shield main body and the consolidation head may include arranging a truncated conical consolidation head whose outer diameter gradually increases toward the rear in the truncated conical space, or arranging the consolidation head in the shape of a truncated cone whose outer diameter gradually increases toward the rear. Cylindrical consolidation heads of substantially the same diameter may be provided. On the other hand, the space in the shield body can also have a cylindrical shape in which the diameter of the inner peripheral surface in the axial direction of the shield body is substantially the same, in which case the consolidation head has an outer diameter that gradually increases toward the rear. It has a conical shape or a truncated conical shape.

In the propulsion device 10 of FIG. 1, when the electric motor 42 is operated, the shaft 22 is rotated via the gears 44 and 40. As the shaft 22 rotates, the eccentric sleeve 32 rotates. At this time, the shield body 12
If there is no material to be excavated within the space 14, the consolidation head 16 will not substantially rotate, but will merely make an eccentric rotational movement within the space 14. However, when the space 14 is filled with the material to be excavated, the consolidation head 16 receives frictional force from the material to be excavated.
As the eccentric sleeve 32 rotates, the consolidation head 16
The contact area with the excavated material gradually moves in the circumferential direction, and the consolidation head 16 comes to rotate around the eccentric sleeve 32 during eccentric rotational movement. In this state, when thrust is applied from the rear of the concrete pipe by jacking, the shield body 1
2 moves forward, and the excavated material excavated from the ground face reaches the consolidation head 16 and the inner peripheral surface 1 of the shield body 12.
8, and is pushed backward by the earth pressure applied from the face. The excavated material thus discharged into the shear chamber 54 is conveyed rearward through the pipe 52.

Inner peripheral surface 1 of consolidation head 16 and shield body 12
Consolidation of the excavated material between the consolidation head 16 and
It is also possible to provide it fixedly to the eccentric sleeve 32. However, when the consolidation head 16 is secured to the eccentric sleeve 32, the consolidation head 1
During the eccentric rotation movement of No. 6, a large frictional force, that is, a static frictional force, acts between the consolidation head and the excavated material. On the other hand, if the consolidation head 16 is rotatable relative to the eccentric sleeve 32, the consolidation head 16
Since a small dynamic frictional force acts between the excavated material 6 and the excavated object, the load on the electric motor 42 becomes sufficiently small.

For example, as shown in phantom lines in FIG.
The drive mechanism 30 can also be constructed by attaching internal gears 74 that mesh with the respective ones. According to this, since the consolidation head 16 can be rotated by both gears, it is possible to prevent the rotational speed of the consolidation head 16 from varying due to the frictional force of the excavated object. In this case, the gear may be mounted at a location other than that shown in the drawings, such as between the consolidation head 16 and the shaft 22. Further, the consolidation head 16 can also be provided with an internal gear.

The shield propulsion device 80 shown in FIG. 2 has a truncated cone-shaped space 14 surrounded by an inner circumferential surface 18 whose diameter gradually decreases toward the rear, in front of the bulkhead 20 of the shield body 12. , inner peripheral surface 18
The shield propulsion device 10 is the same as the shield propulsion device 10 in that the consolidation head 16 is disposed surrounding the shaft 22 with its axis eccentrically e from the shaft 22 in the space 14 surrounded by the shield propulsion device 10. Furthermore, the arrangement of the shaft 22 and its support are the same as in the shield propulsion device 10.

However, the shield propulsion system 80 shown in FIG. 2 includes a drive mechanism 82, which is different from the drive mechanism 30 of the shield propulsion system 10, for causing eccentric rotational movement of the consolidation head 16 about the axis 22.

The drive mechanism 82 includes an eccentric sleeve 84 and a drive source 8
5, a first gear 86, and a second gear 88. The eccentric sleeve 84 has a circular cross-sectional shape, and a hole 83 having an axis is bored in the eccentric sleeve 84 at a position offset by e from the center of the circle. The hole 83 is formed with a loose fit on the shaft 22, and the eccentric sleeve 84 is fitted with a pair of needle bearings 9 disposed at both ends of the hole 83.
0 on the shaft 22. On the other hand, a ball bearing 92 is arranged on the front side of the eccentric sleeve 84, and this ball bearing 92 is connected to the stopper 9.
4 is locked. Further, a ball bearing 96 is arranged on the rear side of the eccentric sleeve 84, and this ball bearing 96 is locked to a boss of the second gear 88. As a result, the eccentric sleeve 84 is rotatable relative to the shaft 22 and immovable in the axial direction.

The drive source 85 has the same configuration as the drive source 34. That is, it includes a gear 40 that is keyed to the shaft 22, an electric motor 42, and a gear 44 that meshes with the gear 40 that is keyed to the output shaft of the motor.

The consolidation head 16 has a pair of rolling bearings 36,3.
8 and is rotatably supported on an eccentric sleeve 86. A first gear 86 is connected to this consolidation head 16.
In the illustrated example, it is an internal gear. A second gear 88 meshing with the first gear 86 is an external gear integrally provided on the shaft 22 , and both gears 86 and 88 are covered by a cover 70 and a sealing device 64 .

The first gear 86 is an internal gear, and the second gear 86 is an internal gear.
When 8 is an external gear, both gears 86 and 88 mesh on a line connecting the axis O ₁ of the shaft 22 and the center O ₂ of the circle of the eccentric sleeve 84, as shown in FIG.
This position shifts in the circumferential direction as the shaft 22 rotates.

On the other hand, since the consolidation head 16 has a conical shape, a difference in circumferential speed occurs over the range from its front end to its rear end. However, in reality, the consolidation head 16 is considered to rotate based on the location where the consolidation resistance of the excavated object is greatest depending on the nature, size, shape, and other properties of the excavated object.

The shaft 22, the eccentric sleeve 84, and the consolidation head 16 constitute a planetary mechanism by interposing two gears 86 and 88. Now, the number of rotations of the eccentric sleeve 84 is N ₁ , the number of rotations of the shaft 22 is N, the number of teeth of the first gear 86 provided on the consolidation head is Z ₁ , and the number of teeth of the second gear 88 provided on the shaft is number
Z ₂ and resistance is applied in the direction that the consolidation head 16 is not rotated, the rotational speed of the eccentric sleeve 84 is given by N ₁ =Z ₂ /Z ₂ -Z ₂ ×N.

From the above equation, it can be seen that the eccentric sleeve 84 is rotated by a different number of rotations than the number of rotations of the shaft 22. In planetary mechanisms, it is customary to set the value of (Z ₁ -Z ₂ ) to be 2 to 3. Therefore, when the gear 86 provided in the consolidation head 16 is an internal gear, the rotation speed of the eccentric sleeve 84 is determined by the above formula.
For example, if the number of teeth Z ₁ of the gear 86 is 20 and the number of teeth Z ₂ of the gear 88 is 17, the speed will be increased by 5.7 times.

When the speed of the eccentric sleeve 84 is increased, the consolidation head 16 rotates eccentrically at the same number of rotations as the eccentric sleeve 84, so that the excavated material is consolidated more frequently. As the frequency of consolidating the excavated material in the radial direction increases, a horizontal gap will occur between the consolidation head and the excavated material, so the horizontal force, which is the axial force applied to the consolidation head 16, is reduced. Therefore, the reaction force acting on the ground face becomes smaller. Therefore, in order to increase this reaction force, the thrust force exerted on the shield body 12 is increased to maintain a predetermined earth pressure.

The basic operation of the shield propulsion device 80 shown in FIG. 2 is the same as that of the shield propulsion device 10 shown in FIG. However, according to the shield propulsion device 80 shown in FIG.
Since the rotation speed of the shaft 22 is increased by the eccentric sleeve 84 and the consolidation head 16 is rotated eccentrically, a strong eccentric force can be obtained. As a result, the compaction effect of the excavated material is enhanced, and it becomes possible to crush large gravel. In addition, since the consolidation head 16 consolidates the part of the excavated object that requires the most resistance while rolling, wear of the consolidation head 16 can be reduced, and the driving source 85
power can be reduced.

In the shield propulsion device 100 shown in FIG. 4, a truncated cone-shaped space 14 is provided in front of a partition wall 20 of a shield main body 12 and is surrounded by an inner circumferential surface 18 whose diameter gradually decreases toward the rear. point, within this space 14, the consolidation head 16 has its axis aligned with the axis 22.
This is the same as the shield propulsion device 10 in that the shield propulsion device 10 is arranged around the shaft 22 with only e eccentric from the axis of the shield propulsion device 10 .

However, the shield propulsion device 100 shown in FIG.
includes a drive mechanism 102, different from the drive mechanism 30 of the shield propulsion device 10 or the drive mechanism 82 of the shield propulsion device 80, for causing eccentric rotational movement of the consolidation head 16 about the axis 22.

The drive mechanism 102 includes an eccentric sleeve 104 and a first
A drive source 106 and a second drive source 108 are provided. The shaft 22 is supported in two rolling bearings 48 arranged in the casing 46 behind the partition wall 20 and in a rolling bearing 28 arranged in a bearing part 27 of the rib 26 in front of the space 14. An eccentric sleeve 104 is arranged around this shaft 22.

The eccentric sleeve 104 has an eccentric portion 110 each having a circular outer diameter and a shaft portion 112 extending rearward from the eccentric portion. A hole 111 having an axis is opened in the eccentric portion 110 at a position offset by e from the center of the circle. This hole 111 extends into the shaft portion 112 and extends into the shaft portion 112.
Its axis is aligned with the center of the circle.
The shaft portion 112 projects rearward through a rolling bearing 113 arranged on the bulkhead 20. Hole 111
is formed with a loose fit on the shaft 22,
The eccentric sleeve 104 is connected to the shaft 2 through a pair of needle bearings 90 arranged at both ends of the hole 111.
It is supported by 2. On the other hand, the eccentric sleeve 104
A ball bearing 92 is arranged on the front side, and this ball bearing 92 is locked to a stopper 94. Further, a ball bearing 96 is arranged on the rear side of the eccentric sleeve 104, and this ball bearing 96 is locked to a gear of a second drive source 108, which will be described later. As a result, the eccentric sleeve 104
is rotatable about the shaft 22 and immovable in the axial direction.

The first drive source 102 includes a gear 114 keyed to a shaft portion 112 of the eccentric sleeve 104, an electric motor 116, and a gear 118 meshing with the gear 114, keyed to the output shaft of the electric motor.

The second drive source 108 is the same as the drive source 34 and includes a gear 40 keyed to the shaft 22, an electric motor 42, and a keyed to the output shaft of the motor.
A gear 44 that meshes with the gear 40 is provided.

The consolidation head 16 has a pair of rolling bearings 36,3.
Eccentric portion 110 of eccentric sleeve 104 via 8
is rotatably supported. This consolidation head 1
6 is a drive source 10 separate from the drive source 108 of the shaft 22;
6, the shaft 22
It can be rotated in the opposite direction of rotation. Therefore,
A spiral convex portion 118 is provided on the outer periphery of the consolidation head 16, and this convex portion 118 can provide a screw conveyor function, and it is possible to enhance the effect of discharging the excavated material. If the direction of rotation of the consolidation head 16 is uniquely determined by the direction of rotation of the shaft 22, the shaft 22 may be rotated forward or backward, so it is not possible to provide a spiral convex portion on the outer periphery of the consolidation head.

The basic operation of the shield propulsion device 100 shown in FIG. 4 is the same as that of the shield propulsion device 100 shown in FIGS. 1 and 2. However, the shield propulsion device 10 in FIG.
0, the eccentric sleeve 104 can be rotated independently of the rotation of the shaft 22, so that the excavated material can be consolidated even when the cutter 56 is stopped, and
The direction and speed of rotation of the consolidation head 16 can be freely selected independently of the direction and speed of rotation of the shaft 22. This allows the consolidation head 16 to perform an optimal eccentric rotational movement depending on the properties of the excavated object.

(Effects of the Invention) According to the present invention, since the excavated material is guided straight to the discharge port by consolidation and soil pressure, the frictional force between the excavated material and the bulkhead can be reduced, and the consolidation head is Since the excavated object rolls at the part where the greatest resistance is applied, the power load on the drive source can be reduced. As a result, the entire propulsion device can be made more compact. Furthermore, since the consolidation head rotates relative to the excavated material, wear on the consolidation head can be reduced.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view of a shield propulsion device according to the present invention, Fig. 2 is a cross-sectional view showing another embodiment of the shield propulsion device, and Fig. 3 is a cross-section taken along line 3-3 in Fig. 2. 4 are sectional views showing still another embodiment of the shield propulsion device. 10, 80, 100: Shield propulsion device, 1
2: Shield body, 14: Space, 16: Consolidation head, 18: Inner peripheral surface, 20: Partition wall, 22: Shaft, 3
0, 82, 102: Drive mechanism, 32, 84, 10
4: Eccentric sleeve, 34, 85, 106, 10
8: Drive source, 56: Cutter, 64: Sealing device,
86, 88: Gear.

Claims (1)

[Scope of Claims] 1. A cylindrical shield body, having a partition wall provided in the diametrical direction of the shield body, and a space provided in front of the partition wall and surrounded by the inner circumferential surface of the shield main body; The diameter of the circumferential surface gradually decreases toward the rear,
a shield body defining the truncated conical space; and an axis extending from the rear of the partition wall to the front thereof;
a rotatable consolidation head disposed surrounding the shaft in the space, the consolidation head having its axis offset from the axis of the shaft; and a drive mechanism for eccentrically rotating the consolidation head with respect to the shaft;
A shield propulsion device comprising means for discharging excavated material from a front area of the bulkhead to a rear area thereof, and a jack located behind the shield body and applying a thrust to the shield body. 2. The consolidation head according to claim 1, wherein the consolidation head has a conical or truncated conical shape whose outer diameter gradually increases toward the rear, or a cylindrical shape whose outer diameter in the axial direction is substantially the same. shield propulsion device. 3. The drive mechanism includes an eccentric sleeve disposed between the shaft and the consolidation head and fixed to the shaft, which rotatably supports the consolidation head, and an eccentric sleeve that rotatably supports the consolidation head; Claim 1, comprising: a drive source connected to the
The shield propulsion device described in section. 4. The drive mechanism includes an eccentric sleeve disposed between the shaft and the consolidation head and fixed to the shaft, which rotatably supports the consolidation head, and an eccentric sleeve that rotatably supports the consolidation head; The shield propulsion device according to claim 1, comprising a drive source connected to the consolidation head, a first gear provided on the consolidation head, and a second gear meshing with the first gear. . 5. The drive mechanism includes an eccentric sleeve disposed between the shaft and the consolidation head and rotatably supported by the shaft, the eccentric sleeve rotatably supporting the consolidation head, and a rear portion of the partition wall. a drive source coupled to the shaft, a first gear provided on the consolidation head, and a second gear provided on the shaft to mesh with the first gear;
A shield propulsion device according to claim 1. 6. The drive mechanism is an eccentric sleeve rotatably supported on the shaft, and is arranged between the shaft and the consolidation head and includes an eccentric portion that rotatably supports the consolidation head, and an eccentric portion rearward from the eccentric portion. an eccentric sleeve having a shaft portion extending toward the partition wall and projecting rearward through between the partition wall and the shaft; a first driving source connected to the shaft portion of the eccentric sleeve behind the partition wall; The shield propulsion device according to claim 1, further comprising: a second driving source connected to the shaft behind the partition wall. 7. The shield propulsion device according to claim 6, wherein the consolidation head has spiral irregularities on its outer periphery. 8. The shaft is supported in a bearing provided on the bulkhead behind the consolidation head and supported in a bearing provided in the shield body in front of the consolidation head. The shield propulsion device described. 9. A sealing device provided between the consolidation head and a portion near each bearing, the sealing device including a ring movable in the axial direction of the shaft, the sealing device being provided at one of the consolidation head and the portion near the bearing. ,
9. The shield propulsion device according to claim 8, further comprising a spring biasing the ring toward the other side. 10 A cylindrical shield body having a partition wall provided in the diametrical direction and a space provided in front of the partition wall and surrounded by the inner circumferential surface of the shield main body, the diameter of the inner circumferential surface being the same as that of the shield body. a shield body that is substantially the same in the axial direction of the bodies and defines the cylindrical space; a shaft extending from the rear of the bulkhead to the front thereof; and a consolidation head disposed around the shaft within the space. a rotatable consolidation head whose axis is eccentric from the axis of the shaft; a drive mechanism for eccentrically rotating the consolidation head with respect to the shaft; A shield propulsion device comprising: ejecting means; and a jack located behind the shield body and applying thrust to the shield body. 11. The consolidation head has a conical shape or a truncated conical shape, with the outer diameter gradually increasing toward the rear.
A shield propulsion device according to claim 10.