JP2004068349A - Shield machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the generation of cracks by suppressing lateral forces acting on segments. <P>SOLUTION: A shield machine 10 is provided with an excavating body 12 and a cutter head 14. A thrusting shield jack 30 is provided in the excavating body 12. A spreader 50 abutting against a segment 32 is disposed at the extensible end of the shield jack 30. A section where the spreader 50 abuts against the segment 32 is made slidable along the radial direction of a tunnel. The spreader 50 has a body 50a fixed to the end of the extensible plunger 30b, an abutting plate 50b slidably supported by the body 50a in the radial direction of the tunnel and abutting against the segment 32 when the plunger 30b is stretched, and a sliding member 50c interposed between the body 50a and the abutting plate 50b. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a shield machine, and more particularly to an improved technique of a shield jack for propulsion of a shield machine.
[0002]
[Prior art]
Various types of shield excavators used when constructing tunnels by the shield method are provided, including earth pressure type shield excavators. For example, Japanese Patent Application Laid-Open No. 2000-320298 discloses an earth pressure type excavator. An example of a shield machine is disclosed.
[0003]
This type of excavator, including the one disclosed in the above-mentioned publication, is generally rotatably supported on a cylindrical excavator body and a tip end side of the excavator body, and is driven to rotate by the ground. And a shield jack installed in the excavator main body and propelling the excavator main body by applying a reaction force to a segment which is annularly assembled on the rear side of the excavator main body.
[0004]
In the shield machine having such a configuration, a plurality of shield jacks installed in the main body are installed at predetermined intervals along the circumferential direction of the tunnel in accordance with the diameter of the tunnel to be constructed.
[0005]
The shield jack used for the shield excavator is usually of a hydraulic drive type, and includes a cylindrical main body and a telescopic plunger partially incorporated in the main body, and requires a large propulsion force. Therefore, those having a considerably large diameter are used.
[0006]
On the other hand, the segment where the shield jack takes a reaction force is assembled in an annular shape along the excavated tunnel inner wall surface. In this case, there is a considerable difference between the diameter of the shield jack body and the thickness of the segment, and there is a considerable amount of eccentricity between the axis of the shield jack and the center in the thickness direction of the segment. However, only a part of the shield jack comes into contact with the segment, and it is difficult to secure a sufficient reaction force.
[0007]
Therefore, conventionally, such a problem has been dealt with by interposing a spreader portion between the telescopic plunger of the shield jack and the segment. However, such a conventional shield machine has a technical problem described below.
[0008]
[Problems to be solved by the invention]
That is, even when the spreader portion is interposed between the telescopic plunger of the shield jack and the segment, the axis of the telescopic direction of the shield jack and the center of the thickness of the segment remain eccentric.
[0009]
In this case, since the center of the thickness of the segment is located outward with respect to the axis of the shield jack, when the shield jack is extended and brought into contact with the segment to take a reaction force, A lateral component force that pushes the segment outward acts, and when such a lateral component force is applied to the end of the segment, cracks may occur in the segment during construction of curved parts or when high thrust acts. Occurred.
[0010]
If such cracks occur in the segment, particularly in tunnel construction where secondary lining is omitted, the segment itself becomes a finished surface, and repair and repair thereof require a great deal of cost and time.
[0011]
The present invention has been made in view of such a conventional problem, and an object of the present invention is to reduce the occurrence of cracks by alleviating or suppressing the lateral component force applied to a segment. It is to provide a shield machine that can perform the work.
[0012]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides a cylindrical excavator main body, a cutter head that is rotatably supported at a tip end side of the excavator main body and excavates a ground by being rotationally driven, A shield jack that is installed in the excavator body and takes a reaction force on a segment that is annularly assembled on the rear side of the excavator body to shield the excavator body. A spreader portion that comes into contact with the segment is arranged at the expansion / contraction end, and a portion where the spreader portion comes into contact with the segment is configured to be slidable along the tunnel radial direction.
[0013]
According to the shield excavator configured as described above, the spreader portion that comes into contact with the segment is arranged at the telescopic end of the shield jack, and the portion where the spreader portion comes into contact with the segment is slidably movable along the tunnel radial direction. When the lateral component force that pushes the segment outward due to the eccentricity between the axis of the shield jack and the center of the thickness of the segment acts, the part that contacts the segment slides along the tunnel radial direction. Move to reduce or suppress the lateral component force from being applied to the segment.
[0014]
The spreader portion is disposed at an end of a telescopic plunger of the shield jack, and the center axis of the tunnel jack in the axial direction of the tunnel may be eccentric to a position shifted in parallel outward with respect to the axis of the shield jack. it can.
[0015]
The spreader portion includes a main body fixed to an end of the telescopic plunger, and a contact plate supported by the main body so as to be slidable in a tunnel radial direction, and when the telescopic plunger is extended, comes into contact with the segment. And a sliding member interposed between the main body and the contact plate.
[0016]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. 1 to 4 show one embodiment of a shield machine according to the present invention. The embodiment shown in the figure illustrates a case where the present invention is applied to a muddy shield machine.
[0017]
The shield machine 10 shown in FIG. 1 includes a machine body 12, a cutter head 14, a partition 16, and a chamber 18. The excavator body 12 has a cylindrical front body portion 12a and a rear body portion 12b having both ends opened, and a rear end portion of the front body portion 12a and a front end portion of the rear body portion 12b are bent at the center. It is a so-called center-bending method, which is connected via the reference numeral 20.
[0018]
The cutter head 14 is rotatably supported on the tip end side of the front trunk portion 12a of the excavator body 12, and has a thick disk-shaped face plate 14a, and a center cutter 14b protruding from the center of the face plate 14a. , A rotation shaft 14c extending at the center of the back side of the face plate 14a.
[0019]
A not-shown excavation bit is arranged on the front surface of the face plate 14a, and a slit-shaped opening for taking in excavated earth and sand is provided near the excavation bit. A copy cutter 14f that appears and disappears in the radial direction is built in the face plate 14a. The copy cutter 14f is protruded and retracted by a jack (not shown) provided in the face plate 14a. When the copy cutter 14f is in a protruding state, excavation with a diameter larger than the diameter of the excavator body 12 is enabled. Further, a plurality of agitating blades 14g for agitating the excavated earth and sand are provided in the chamber 18 on the back side of the face plate 14a.
[0020]
The partition 16 is on the back side of the cutter head 14 and separates the chamber 18. In the case of the present embodiment, the partition 16 is formed in a disk shape having the same diameter as the excavator main body 12. The outer peripheral edge is fixed to the inner peripheral surface of the front trunk portion 12a at a position retracted rearward from the front trunk portion 12a by a predetermined distance and perpendicular to the longitudinal axis of the front trunk portion 12a. .
[0021]
The rotating shaft 14c of the cutter head 14 is rotatably supported by the partition 16 and a driving device 14h for rotating and driving the face plate 14a of the cutter head 14 is connected to an end of the rotating shaft 14c penetrating the partition 16. .
[0022]
The face plate 14a is rotationally driven by the driving device 14h in the chamber 18 separated by the partition wall 16 on the rear side of the cutter head 14, and the earth and sand excavated by the bit is taken in through the opening.
[0023]
A mud pipe 22 for supplying muddy water mixed with excavated earth and sand taken into the chamber 18 is provided through the upper side of the partition wall 16, and a tip of the mud pipe 22 is opened into the chamber 18. .
[0024]
Further, a drain pipe 24 for discharging a mixture of muddy water and excavated earth and sand to the outside is provided below the partition wall 16, and a tip of the drain pipe 24 is opened in the chamber 18. This opening serves as a discharge port 26 for excavated earth and sand.
[0025]
A shield jack 30 for propulsion is provided in the machine body 12. As the excavation progresses, the shield jack 30 applies a reaction force to the segments 32 that are sequentially assembled in an annular shape on the rear end side of the rear trunk portion 12b of the excavator main body 12, thereby propelling the excavator main body 12.
[0026]
The basic configuration of the above-described muddy shield excavator is the same as that of a conventional machine of this type, but the shield excavator 10 of the present embodiment has remarkable features in the points described below. .
[0027]
That is, in the case of the present embodiment, the spreader portion 50 that comes into contact with the segment 32 is disposed at the telescopic end of each shield jack 30, and the portion where the spreader portion 50 comes into contact with the segment 32 slides along the tunnel radial direction. It is freely configured.
[0028]
A plurality of shield jacks 30 are provided at predetermined intervals along the circumferential direction of the excavator main body 12, and each of the shield jacks 30 is a cylindrical jack main body 30a and a part is built in the jack main body 30a. The jack body 30a is fixed to the inner surface of the rear trunk portion 12a of the excavator body 12 via the flange portion 30c.
[0029]
In the case of this embodiment, when the shield jack 30 is driven by hydraulic pressure injection, the telescopic plunger 30b extends rearward along the tunnel axis direction.
[0030]
The spreader portion 50 is supported by the main body 50a fixed to the end of the telescopic plunger 30b, and slidably movable in the tunnel radial direction by the main body 50a. When the telescopic plunger 30b is extended, the contact plate comes into contact with the segment 32. 50b and a sliding member 50c interposed between the main body 50a and the contact plate 50b.
[0031]
The main body 50a of the spreader portion 50 is disposed at the end of the telescopic plunger 30b of the shield jack 30, is pivotally supported by the telescopic plunger 30b by a pin, and the central axis L1 in the tunnel axis direction is the axis of the shield jack 30. It is eccentric with respect to the center L2 to a position moved outward in parallel. The center axis L1 of the main body 50a substantially coincides with the center L3 of the segment 32 in the thickness direction.
[0032]
The contact plate 50b is formed of a substantially rectangular flat plate, and the width arranged in the tunnel radial direction is slightly larger than the thickness of the segment 32, and the center in the width direction is the center axis L1 of the main body 50a. Matches.
A pair of stepped long holes 50d are drilled at the longitudinal end of the contact plate 50b, and are attached to the main body 50a by mounting pins 50e in the stepped long holes 50d. .
[0033]
The long hole 50d has a slightly larger width than the pin 50e, and extends a predetermined length along the tunnel radial direction. With this configuration, the contact plate 50b allows the pin 50e to be connected to the long hole 50d. By moving within the tunnel, it is slidable in the tunnel radial direction.
[0034]
The sliding member 50c is, for example, a porous oiles member, in which a plurality of flat, flat members are interposed, and facilitates sliding movement of the contact plate 50b in the tunnel radial direction.
[0035]
Now, according to the shield machine described above, the spreader portion 50 that contacts the segment 32 is arranged at the telescopic end of the shield jack 30, and the portion where the spreader portion 50 contacts the segment, that is, the contact plate 50b is configured to be slidable along the tunnel radial direction, so that the eccentricity between the axis L2 of the shield jack 30 and the thickness center L3 of the segment 32 causes the segment 32 to be pushed outward. When a force is applied, a portion that comes into contact with the segment 32, that is, the contact plate 50 b slides along the tunnel radial direction, and reduces or suppresses the application of a lateral component to the segment 32.
[0036]
In this way, when the lateral component force applied to the segment 32 is reduced or suppressed, it is possible to reduce the occurrence of cracks in the segment 32 during the construction of the curved portion or when a high thrust is applied. .
[0037]
Therefore, in the tunnel construction in which the secondary lining is omitted, even if the segment itself becomes the finished surface, it is possible to avoid a large cost and time from repairing the crack.
[0038]
In the above embodiment, the case where the present invention is applied to a muddy shield machine is illustrated. However, the embodiment of the present invention is not limited to this type, and may be applied to other types of shield machine. can do.
[0039]
【The invention's effect】
As described above in detail, according to the shield machine according to the present invention, the occurrence of cracks can be reduced by suppressing the lateral force applied to the segments.
[Brief description of the drawings]
FIG. 1 is an overall configuration diagram showing one embodiment of a shield machine according to the present invention.
FIG. 2 is an enlarged view of a main part of the shield jack shown in FIG.
FIG. 3 is a side view of FIG. 2;
FIG. 4 is a front view of FIG. 2;
[Explanation of symbols]
Reference Signs List 10 shield excavator 12 excavator main body 14 cutter head 30 shield jack 30a jack main body 30b telescopic plunger 32 segment 50 spreader section 50a main body 50b contact plate

Claims (3)

A cylindrical excavator body,
A cutter head that is rotatably supported on the tip side of the excavator body and excavates the ground by being rotationally driven,
A shield machine equipped with a shield jack installed in the machine body and taking a reaction force on a segment assembled in an annular shape on the rear side of the machine body to propell the machine body,
A spreader portion that abuts the segment at the telescopic end of the shield jack, and a portion where the spreader portion abuts the segment is configured to be slidable along the radial direction of the tunnel. Machine. The spreader portion is disposed at an end of a telescopic plunger of the shield jack, and a central axis in a tunnel axial direction is eccentric to a position shifted in parallel outward with respect to an axis of the shield jack, The shield machine according to claim 1, wherein the shield machine substantially coincides with the center of the segment in the thickness direction. The spreader section includes a main body fixed to an end of the telescopic plunger, and a contact plate that is slidably supported in the main body so as to be slidable in a tunnel radial direction, and that contacts the segment when the telescopic plunger extends. The shield machine according to claim 1 or 2, further comprising a sliding member interposed between the main body and the contact plate.

Images