JP2510097B2 - Square shield excavator - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a square shield excavator used for constructing tunnels, holes, grooves, etc. having a square cross section.

[0002]

2. Description of the Related Art A square shield excavator for excavating a tunnel having a quadrangular cross-sectional shape, which enables linear reciprocating motion in a direction orthogonal to an axis of the main body of a square cylindrical shield main body. In addition, there is one in which a plurality of support rods arranged at intervals from each other and a plurality of cutter bits attached to the respective support rods are used as excavating means (Japanese Patent Laid-Open No. HEI-1).
-310089). In this excavator, the inside of the main body is divided into a front area maintained at high pressure by a partition wall and a rear area maintained at atmospheric pressure, and the support rod moves to a support plate arranged in the front area in parallel with the partition wall. Supported as possible. This excavator excavates a face by the linear reciprocating motion of each cutter bit accompanying the linear reciprocating motion of a support rod.

As another one of the rectangular shield excavators, a drum disposed in the front part of a rectangular cylindrical shield main body so as to be rotatable around an axis extending in a direction intersecting the axis of the main body, and a drum of the drum. There is one that uses a large number of cutter bits attached to the outer peripheral surface as an excavating means (Japanese Patent Laid-Open No. HEI 2-
66295). This excavator excavates a face by the rotary motion of each cutter bit that accompanies the rotary motion of a drum.

However, in the former case, since the support plate acts as a face plate that receives earth pressure, the amount of excavated material that moves rearward through the support plate is small, and therefore excavation efficiency is low.
Further, since the range of reciprocating movement of the cutter bit is small, it is not possible to excavate the ground containing large gravel.

In the latter case, since the excavated material is rotated around the axis line with the rotation of the drum and the cutter bit, the excavated material cannot be effectively taken into the main body,
Therefore, excavation efficiency is low. In particular, in the case of an excavator that divides the main body into a front area and a rear area and discharges excavated material in the front area with muddy water, the entire front area acts as a mud chamber, so the excavated material in the front area is slurry-like. As a result, the amount of excavated material reaching the outlet and discharged from the outlet is small, and excavation efficiency is low.

[0006]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a square shield excavator capable of efficiently excavating a tunnel, a hole or a groove having a rectangular cross section.

[0007]

A square shield excavator according to the present invention has a rectangular cylindrical shield main body having a space for receiving an excavated object at a front end thereof, and a pair of outer surface portions of the main body in a direction orthogonal to each other. Excavating means having an extending excavating portion, and a drive for giving the excavating means an angular reciprocating motion around the axis so as to draw the excavating portion an arcuate trajectory centered on an axis extending in the direction of the excavating portion. And means for ejecting the excavated material in the space out of the body.

The excavator receives thrust from a thrust generator that advances the excavator. While the excavator is being advanced, the excavating means is provided with an angular reciprocating motion about the axis, that is, a swinging motion about the axis, by the driving means to excavate the face. The excavation is received in the space formed in the body. The excavated material in the space moves backward in the space as the excavator moves forward, and is finally discharged to the outside of the main body by the discharging means.

According to the present invention, since the excavated material is reliably moved in the space of the main body to the rear as the excavator moves forward, the amount of excavable material that can be discharged is large and therefore the excavation efficiency is high. Further, since the range of reciprocating motion of the excavating portion can be widened, it is possible to excavate the ground including large gravel.

The space may have a shape in which the dimension in the direction orthogonal to the axis gradually decreases from the front portion toward the rear portion.

The space is divided into a shear chamber for receiving the excavated material and a mud chamber for receiving the excavated material from the shear chamber,
The excavated material in the muddy water chamber can be discharged by the muddy water type discharging means. The muddy water is supplied to the muddy water chamber through the first pipe, and the excavated material in the muddy water chamber is discharged together with the muddy water through the second pipe.

The drive means includes a shaft extending in the direction of the axis and arranged in the body so as to be angularly rotatable about the axis, and a pair of drive mechanisms for applying power to both ends of the shaft. Is preferably provided. As a result, as compared with the case where power is applied to one end of the shaft, it is possible to transmit a large amount of power to the shaft by using a drive mechanism that generates a large amount of power.

The excavating means includes an arm supported by the shaft and extending in the front-rear direction, a support rod attached to the tip of the arm and extending in the axial direction, and the support rod in the axial direction. And a plurality of attached bits.

Further, it is preferable to include means for detecting a range of angular reciprocating motion of the excavating means. This makes it possible to regulate the amount of excess excavation by the excavation means.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIGS. 1 to 5, a square shield excavator 10 includes a square cylindrical shield body 12. Body 1
2 includes first and second rectangular tube-shaped main bodies 14 and 16 which are butted against each other. The first and second main bodies 14 and 16 can be separated by a plurality of bolts 18 shown in FIG. It is connected.

In the illustrated example, the main body 12 applies a thrust generated by a thrust generating device such as a source pushing device (not shown) to the excavator 1
It is advanced by receiving it through a plurality of square-pipe-shaped pipes 20 which are pushed into the excavation mark by 0. However, as the thrust generating device, for example, as shown in FIG. 6, a device including a plurality of jacks 24 having the lining 22 constructed on the excavation mark by the excavator 10 as a reaction force body may be used.

The first main body portion 14 has a shear chamber 26 for receiving the excavated material, a muddy water chamber 28 following the rear portion of the shear chamber, and an atmospheric pressure chamber 30 communicating with the inside of the second main body portion 16.
The shear chamber 26 and the muddy water chamber 28 are separated from the atmospheric pressure chamber 30 by a plurality of wall members 32 that are attached to the main body 12 and define blade edges, and a case 34 that is connected to the wall members. The case 34 has a first rib 36,
It is supported by the main body portion 14.

The shear chamber 26 has a gap in the first direction orthogonal to the pair of outer surface portions of the main body 12 and a gap in the second direction orthogonal to the other pair of outer surface portions of the main body 12 from the front. It has a truncated pyramid shape that gradually narrows toward the rear. On the other hand, the muddy water chamber 28 has a trapezoidal cross-sectional shape in which the interval extending in the first direction is gradually narrowed from the front to the rear, but the interval in the second direction is substantially the same.

At the boundary between the shear chamber 26 and the muddy chamber 28,
A shaft 38 extending in the first direction is arranged. As shown in FIG. 3, the shaft 38 penetrates the case 34 at both ends. Shaft 38 has its axis 4
The bearing 42, which is rotatably supported around 0, is arranged in a bearing case 46 attached to a boss portion 44 of the case 34.

The shaft 38 is angularly reciprocally rotated about an axis 40 by a pair of drive mechanisms 48 connected to the ends of the shaft 38. In the illustrated example, each drive mechanism 48 includes a double-acting jack 50 that is operated by a hydraulic fluid such as hydraulic pressure, pressure water, or compressed air, and a shilling of the jack 50 at the rear end of the first main body portion 14. Attached rectangular end plate 52
And a link 56 that connects the piston rod of the jack 50 to the end of the shaft 38.

The bracket 54 is attached to the end plate 52 with bolts or the like, and the link 56 is attached to the end of the shaft 38 with bolts or the like. Each bracket 54 and jack 50, and each link 56 and jack 5
Each 0 is pivotally connected. Both links 5
6 are arranged at angular intervals around the axis of the shaft 38.

A rotor 58 is attached to the shaft 38 by a plurality of keys 60 so as not to be relatively displaced. The rotor 58 has a polygonal (14-sided in the example shown) outer surface as shown in FIGS. 4 and 5, and the axis 4 is arranged so that its center is ahead of the axis 40 by a distance e.
It is eccentric to 0. A plurality of protrusions 62 are provided on the outer peripheral surface of the rotor 58 and the inner surface of the case 34 corresponding thereto.
Are formed.

As shown in FIG. 3, a known mechanical seal 6 is provided between each end of the rotor 58 in the direction of the axis 40 and the corresponding bearing case 46.
4 are arranged.

The rotor 58 has two sets of cutter heads 66.
Has been fixed. Both cutter heads 66 are angularly spaced about the axis 40. Each of the cutter heads 66 has an axial surface 40 of the outer surface of the rotor 58.
A pair of arms 68 extending forward from a position spaced apart in the direction, and a supporting rod 70 connecting the tip ends of the arms 68 to each other.
And a plurality of cutter bits 72 sequentially attached to the support rod 70 in the direction of the axis 40 so as to define an excavated portion extending parallel to the axis 40.

In the illustrated example, the excavator 10 uses a muddy type discharge device. This discharge device is used to remove muddy water from the muddy water chamber 2
8 and a drain pipe 76 for discharging the muddy water in the muddy water chamber 28 together with the excavated material. Each of the pipes 74 and 76 is connected to the case 34 by a connector 80 attached to the case 34 by a plurality of bolts 78.

At the time of excavation, both jacks 50 are operated so as to repeat extension and contraction with a phase shift of 180 degrees. That is, in both jacks 50, the process shown in FIG. 4 in which one jack 50 extends and the other jack 50 contracts at the same time, and the process shown in FIG. 5 in which one jack 50 contracts and the other jack 50 extends at the same time. repeat.

As a result, the link 56 and the shaft 3
Since 8 is angularly reciprocally rotated about the axis 40, the rotor 58 is angularly reciprocally rotated about the axis 40, and the cutter head 66 is swung in a fan shape about the axis 40. As a result, the cutter bit 72 reciprocates along an arc centered on the axis 40 with the excavation portion, that is, the blade portion pressed against the face, thereby excavating the face with the blade.

During excavation, the pressure in the shear chamber 26 is detected by the pressure sensor 82 shown in FIGS. 2 and 3, and
A predetermined pressure is maintained to prevent face collapse. The pressure in the shear chamber 26 can be adjusted by the pressure in the muddy chamber 28, the excavation speed, and the like. The pressure in the muddy water chamber 28 can be adjusted by the amount of muddy water supplied thereto, the amount of muddy water discharged from the muddy water chamber, and the like. Therefore, it is preferable that the pressure in the muddy water chamber 28 is also measured by a pressure gauge (not shown).

The excavated material is received in the shear chamber 26, moved to the inside of the shear chamber 26, and further moved to the mud chamber 28 through the space between the rotor 58 and the case 34.
Finally, it is discharged to the outside of the main body 12 by the drainage pipe 76. The movement of the excavated material in the shear chamber 26 is mainly
The excavator 10 relies on moving forward while excavating the face.

The shear received between the cutter heads 66 is caused by the forward movement of the excavator 10 and the swinging motion of the cutter head 66, and the space 84 between the arms 68 in the shear chamber 26.
(See FIG. 3) and the space 86 (see FIG. 3) between the arm 68 and the wall member 32.

In the excavator 10, with the center of the rotor 58 eccentric forward from the axis 40 by e, the rotor 58
Makes an angular reciprocating rotary motion about axis 40,
When the rotor 58 is moved from the state shown in FIG. 5 to the state shown in FIG. 4, assuming that the directions of the short sides thereof are the vertical direction in FIGS. 4 and 5, the shear chamber 26 is located at the lower portion in FIG. The excavated material therein is sent to the mud chamber 28.

At this time, in FIG. 4, the upper portion of the rotor 58 is moved in the direction of returning the excavated material in the muddy water chamber 28 to the shear chamber 26, but the upper portion of the rotor 58 is the case 34.
Therefore, the excavated material in the muddy water chamber 28 is prevented from returning to the shear chamber 26 at a portion above the rotor 58.

Similarly, when the rotor 58 is moved from the state shown in FIG. 4 to the state shown in FIG. 5, the excavated material in the shear chamber 26 is fed to the mud chamber 28 at an upper portion in FIG. At this time, the portion below the rotor 58 is the case 3
Since it is displaced in a direction largely separated from 4, the muddy water chamber 28
It is prevented that the excavated material therein is returned to the shear chamber 26 at a portion below the rotor 58.

As shown in FIGS. 4 and 5, the large gravel in the excavated material is crushed by being caught between the outer surface of the rotor 58 and the inner surface of the case 34 with the eccentric movement of the rotor 58. .

When the projections 62 provided on the rotor 58 are displaced in the direction in which the excavated material in the shear chamber 26 is fed into the muddy water chamber 28, the excavated material in the shear chamber 26 is moved to the muddy water chamber 28.
And a function of feeding the gravel between the rotor 58 and the case 34 in cooperation with the protrusion 62 provided on the rotor 58.

The excavation range in the direction of the swing motion of the cutter head 66 can be restricted by the range of the swing motion of the cutter head 66.

Therefore, as shown in FIGS. 7 to 10, the excavator 10 further includes a pair of limit switches 88 arranged corresponding to the links 56 to detect the range of the swing motion of the cutter head 66. And a bracket 90 that supports the limit switch. Each bracket 90 is attached to the case 34 by a plurality of bolts 92,
Further, it has an elongated hole 94 extending in the direction of the swing motion of the link 56.

Each limit switch 88 is attached to the bracket 90 by a mounting member 96 consisting of a bolt penetrating the elongated hole 94 and a nut screwed with the bolt so that the position of the link 56 in the swinging direction can be changed. ing. Each link 56 has a protrusion 98 for opening and closing the corresponding limit switch 88 in accordance with the swinging motion of the link 56.

When the jack 50 is expanded and contracted during excavation, the links 56 swing in a fan shape around the axis 40, so that each limit switch 88 causes each projection 98 of the corresponding link 56 to contact the actuator. Generate an electrical signal to. This electric signal is used as a timing signal for switching between extension and contraction of the jack 50.

The range of swing motion of the cutter head 66 is small when the limit switches 88 are arranged in the positions shown in FIG. 9 and large when they are arranged in the positions shown in FIG. Therefore, by changing the mounting position of the limit switch 88 on the bracket 90, the range of the swing motion of the cutter head 66 and the amount of over dug can be changed. The range of swing motion of the cutter head 66 is shown by arc-shaped arrows in FIGS. 9 and 10.

The power for rotating the shaft 38 may be transmitted to one end of the shaft 38. However, as in the illustrated example, the power to rotate the shaft 38 is applied to the shaft 38.
By transmitting the power to both ends of the shaft, a large amount of power can be transmitted by using a jack that generates a large driving force, as compared with the case of transmitting the power to one end of the shaft.

Instead of providing a plurality of cutter heads 66 as in the excavator 10 described above, the excavator 100 shown in FIG.
Alternatively, one cutter head 66 may be provided. Further, another drive mechanism may be used as the drive mechanism that gives the cutter head 66 a swinging motion.

The drive mechanism 102 used in the excavator 100 shown in FIG. 11 has a gear 104 attached to the end of the shaft 38 and a fan-shaped gear 106 meshing with the gear 104.
And a pair of double-acting jacks 108 that give angular reciprocating rotational movement to the gear 106. The gear 106 is supported by the pin 110 so as to be pivotally movable on the first main body portion 14. The cylinder of each jack 108 is pivotally connected to the end plate 52 by a bracket 112, and the piston rod is pivotally connected to one end of the gear 106.

At the time of excavation, both jacks 108 are operated so as to repeat extension and contraction with a phase shift of 180 degrees.
As a result, the gear 106 is swung about the pin 110, so that the gear 104 is angularly reciprocally rotated about its axis. As a result, the shaft 38 and the rotor 5
8 is angularly reciprocally rotated about the axis of the shaft 38, and the cutter head 66 is swung about the axis of the shaft 38.

Excavator 120 shown in FIGS. 12 and 13.
Connects two drive mechanisms 122, which are arranged at intervals in the axial direction of the shaft 38, to one end of the shaft 38.

Each drive mechanism 122, like the drive mechanism 48 shown in FIG. 1, is a double-acting type jack 124 operated by pressure fluid, a bracket 126 for connecting the cylinder of the jack 124 to the end plate 52, and a jack. A link 128 connecting the piston rod of 124 to the end of the shaft 38.
With.

Both links 128 are arranged at angular intervals around the axis of the shaft 38. Both links 1
A collar 130 is arranged between the 28. Both jacks 124 are operated 180 degrees out of phase.

Incidentally, one excavator 10, 100 or 1
Instead of using 20 to build tunnels, holes or trenches, it is possible to build multiple tunnels by using multiple excavators 10, 100 or 120 arranged in a matrix and simultaneously excavating. Good.

Instead of the muddy type discharge device, another discharge device such as a screw conveyor may be used. Further, a part or all of the excavated material in the shear chamber may be discharged around the main body, particularly to the side of the excavator by angular reciprocating rotary motion of the rotor or the like.

[Brief description of drawings]

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

2 is a view of the excavator of FIG. 1 taken along line 2-2. FIG.

FIG. 3 is a sectional view taken along line 3-3 of FIG.

4 is a cross-sectional view taken along line 4-4 of FIG.

FIG. 5 is a sectional view similar to FIG. 3 for explaining the excavated state.

FIG. 6 is a cross-sectional view of an excavator that is advanced by another thrust generator.

FIG. 7 is a sectional view showing a means for detecting an excavation range.

8 is a view taken along line 8-8 of FIG.

9 is a cross-sectional view taken along line 9-9 of FIG.

FIG. 10 is a sectional view similar to FIG. 9 for explaining the excavation range.

FIG. 11 is a cross-sectional view showing an embodiment of an excavator using another drive mechanism.

FIG. 12 is a cross-sectional view showing an embodiment of an excavator using still another drive mechanism.

13 is a cross-sectional view taken along line 13-13 of FIG.

[Explanation of symbols]

 10, 100, 120 Square shield excavator 12 Shield body 26 Shear chamber 28 Mud chamber 34 Case 38 Shaft 40 Axis 48, 102, 122 Drive mechanism 50, 108, 124 Jack 66 Cutter head 68 Arm 70 Support rod 72 Cutter bit 74 Water supply pipe 76 Drainage pipe

Claims (6)

(57) [Claims] 1. A quadrangular cylindrical shield body having a space for receiving a digging object at a front end thereof, digging means having a digging portion extending in a direction orthogonal to a pair of outer surface portions of the main body, and digging means of the digging portion. A driving means for giving the excavating means an angular reciprocating motion around the axis to draw an arcuate locus around an axis extending in the direction, and the excavation object in the space A square shield excavator including a means for discharging to the outside. 2. The space has a shape in which a dimension in a direction orthogonal to the axis is gradually reduced from a front portion to a rear portion.
The tunnel excavator according to claim 1. 3. The space has a shear chamber for receiving excavation and a mud chamber for receiving excavation from the shear chamber,
The excavator according to claim 2, wherein the discharging unit includes a first pipe for supplying muddy water to the muddy water chamber, and a second pipe for discharging the excavated material in the muddy water chamber together with the muddy water. 4. The drive means includes a shaft extending in the direction of the axis and rotatably angularly about the axis in the body, and a pair of drives for applying power to both ends of the shaft. The excavator according to claim 1, comprising a mechanism. 5. The excavating means includes an arm supported by the shaft and extending in the front-rear direction, and a support rod attached to a tip portion of the arm and extending in the axial direction.
The excavator according to claim 4, further comprising: a plurality of bits sequentially attached to the support rod in the direction of the axis. 6. The excavator according to claim 1, further comprising means for detecting a range of reciprocating movement of the excavation means.