JP2000328878A - Tunnel boring machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tunnel boring machine in which a large propulsive force is not required and the machine can be miniaturized and which has a high excavation capacity by rock and can stably hold rotary excavation cutter blades. SOLUTION: A plurality of compressive breaking cutter edges 3 rotationally held at the foremost end of a head excavation disk 2 supported through a bearing 10 at the front end of a tunnel boring machine body 1 are at first brought into contact with natural ground 15 exposed in a shaft to generate a linear compressive breakage and form a small diameter leading hole. As the compressive cutter edges 3 are thrusted, the edge nearest to the central shaft among separation breakage edges 4b is brought into contact with the external surface of the opening of the leading hole to break the inside part so as to separate it at the position where the cutter edges touch the exposed face of the bed rock of the natural ground 15. The one inside-supported separation breakage edge and both side-supported separation breakage edges 4a fitted to the front face of main struts 21 one after another in the direction that the diameter becomes large are sequentially brought into contact with the exposed face of the bed rock of the natural ground 15 to separate the inside thereof. Hence, a nearly conical heading having cylindrical steps can be formed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of crushing a rock in a process in which a plurality of rotary excavating blades are rotatably mounted on a front surface of a head excavator, and the rotary excavating blades abut against a rocky ground and roll. And a tunnel excavator adapted to do so.

[0002]

2. Description of the Related Art When excavating the ground with a shield machine and forming a tunnel, if the soil of the ground is mainly composed of soft earth and sand, a sharp edge is provided in the sliding rotation direction. A drilling propulsion method is adopted in which a rotating excavator with a large number of excavated blades planted on the front surface slides on the ground while it advances, but if the ground is formed of solid rock, In the excavation method in which the excavation blade is propelled by sliding, the excavation blade cannot be used because the excavation blade is damaged or significantly worn. Therefore, when excavating rock mass with a shield machine,
By rotating the rotary excavator, which has a large number of dish-shaped rotary excavating blades on its front surface in a freely rolling manner, in contact with the ground, the rotary excavating blade receives a strong pressing force to remove A crushing crushing method has been adopted in which crushing is performed in a streak shape and adjacent crushing is induced between the crushing groove formed by an adjacent rotary excavation blade.

As described above, in the crushing and crushing method, a large pressure is applied to the rotary excavating blade that rolls on the rock surface to crush it, so that the propulsion mechanism for propelling the shield machine has a large propulsion capacity. In addition, a bearing that rotatably supports the rotary excavation blade and a structure that mechanically supports the shield machine main body need to have strong pressure resistance. In addition, when the bedrock has a large compressive strength, crushing is unlikely to occur. Therefore, in such a case, there is a problem that the digging efficiency of the bedrock by the crushing and crushing method is inferior to the ground.

[0004] By the way, it has been known from the past that the tensile strength of rock is generally a small value of several tenths to one-tenth of the compressive strength. Rather than crushing and crushing by applying force,
Research has been conducted on excavation methods using exfoliation crushing, in which a crack is formed in a bedrock, and pressure is applied to the crack to exert a tensile force along the crack to cause crushing.

For example, Japanese Patent Laid-Open Publication No. Hei 6-503389 discloses that a ring cavity is formed in a face face by a tool arm by rotating motion of a drilling head base, a leading drilling hole by the tool arm and an undercut by an undercut tool. The invention of a tunnel excavation machine configured to perform cutting simultaneously and continuously is disclosed. In this tunnel excavation machine, a ring hollow chamber is formed on the face by the rotating tool arm, and the undercut tool is swiveled in the radial direction along the rear end of the formed ring hollow to change the face. Undercut (peeling and crushing) can be performed.

[0006]

According to the above prior art, a tunnel can be excavated with little pressing force and a small torque. However, this tunnel excavation machine is designed to make a leading hole in the face by rotating the tool arm, and to peel and crush the face by rotating the undercut tool in the radial direction. Not only was the mechanism complicated and the production cost increased, but also the problem was that the excavation ability was low and the excavation efficiency was poor because the main digging operation was performed by the turning movement of the undercut tool in the radial direction. Furthermore, there was a problem that it was not possible to continuously excavate while moving forward. The present invention has been made to solve such a problem in the prior art, and does not require a large propulsion force, so that the machine can be reduced in size and cost, and the excavation ability of the rock mass with respect to the ground is high. An object of the present invention is to provide a tunnel excavator that is excellent in efficiency and can stably support a rotary excavation blade.

[0007]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a rotary excavating blade rotatably mounted on the front surface of a head excavator, which is smaller than a predetermined diameter from the rotation center of the head excavator. A plurality of crushing crushing blades that form a small-diameter leading hole by abutting against the ground in the range to generate a linear crushing crushing, Attached in order toward the outer peripheral side with an interval, each abuts against the ground in a range exceeding a predetermined diameter and peels and crushes the ground to form a cylindrical step in the ground. A plurality of exfoliating crushing blades to be excavated at least, the exfoliating crushing blade attached at least at a position distant from the rotation center or the outer peripheral portion of the head excavator has a double-sided support that supports the bearing on both sides, or a head excavation Close to the center of rotation of the board The peeling and crushing blade attached at the position supports the bearing on one side from the outside, or the peeling and crushing blade attached at the position close to the outer periphery of the head excavator supports the bearing on one side from the inside The inner side is supported.

[0008] The crushing crushing blade attached to a position near the center of rotation of the head excavator first makes contact with the ground to generate a linear crushing crushing and propelled to form a leading hole smaller than a predetermined diameter. I do. The peeling and crushing blade is rearward from the crushing and crushing blade, and is sequentially attached toward the outer peripheral side with a predetermined interval in the radial direction and the rearward direction, and exceeds the predetermined diameter following the crushing and crushing blade. The ground is sequentially contacted with the ground in the range, and the ground is separated and crushed. Thereby, a substantially conical face having a cylindrical step in the ground is formed.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a front view of a tunnel excavator according to an embodiment of the present invention, FIG. 2 is a cross-sectional view of the tunnel excavator taken along a cutting line AA in FIG. 1 parallel to the central axis, and FIG. FIG. 4 is a sectional view taken along line BB parallel to the central axis of the tunnel excavator, FIG. 4 is a side view of a rotary crushing blade supported on both sides, FIG.
(A), (b) is a side view of the rotary crushing blade of one side support.

In these figures, reference numeral 1 denotes a tunnel excavator body for excavating and propelling a ground made of rock, and 2 denotes a head formed of a substantially conical structure rotatably supported at the tip of the tunnel excavator body 1. A part excavator, 21 is four main struts constructed from the front end of the head excavator 2 toward the annular body that defines the rear periphery, and 22 is a front face between the main struts 21 of the head excavator 2. The covering face plate, 23 is an opening plate that defines a rocky gravure intake, which will be described later,
Numeral 24 denotes four sub-columns provided between the main columns 21, and 3 is rotatably supported on a tip of the head excavator 2 around a rotation axis perpendicular to the central axis, and a ground contacting the ground. A plurality of crushing and crushing blades 31 for crushing the bedrock are fixedly supported at the tip of the head excavator 2 and support the plurality of crushing and crushing blades 3 in a parallel and rotatable manner. 4a, 4b, 4c. Are peeling and crushing blades which are rotatably arranged at predetermined intervals along the outer surface of the main support 21 of the head excavator 2, and are supported on both sides for supporting the bearings on both sides, respectively. The outer one-side support and the inner one-side support which are supported on one inner side are shown.

Reference numeral 5 denotes a gravel take-in blade fixed along the outer surface of the sub-pillar 24 at a plurality of predetermined distances to take crushed rock and gravel into a gravel take-in port described below. A gravel intake where the crushed rock pebbles that fall open and fall into fall, 7 is a container that temporarily stores the crushed rock pebbles that have fallen from the gravel intake 6, and 8 is a crushed rock that is stored in the container 7. A gravel transport device that transports gravel to the rear of the tunnel excavator body 1,
Reference numeral 9 denotes a rake blade for smashing crushed rock debris staying at the outermost peripheral portion of the head excavator 2 into the inside of the head excavator 2, and reference numeral 10 denotes a bearing portion of the head excavator 2 with respect to the tunnel excavator body 1. Bearing 11 is the internal space of the head excavator 2 and the tunnel excavator body 1
15 is a rotating head excavator 2
It is a ground that is excavated.

FIG. 6 is a cross-sectional view passing through the center axis of the peeling and crushing blade 4a supported on both sides. In the figure, reference numeral 41 denotes an annular crushing blade portion which comes into contact with the bedrock of the ground 15 and separates and crushes; 42, a cylindrical rotary support member which integrally supports the crushing blade portion 41;
Reference numeral 3 denotes an annular stopper for fixing the crushing blade portion 41 to the rotating support 42, and reference numeral 44 denotes an annular sealing for sealing a lubricant filled between the rotating support 42 and a fixed support described later. Timber,
Reference numeral 45 denotes a spherical bearing made of a plurality of super-hard alloys which are rotatably inserted into annular grooves formed in respective opposing portions of the rotary support 42 and a support shaft described later, and 46 denotes a rotary support 42. And roller-shaped bearings made of a plurality of super-hard alloys rotatably inserted into annular grooves formed in the opposite portions to the support shaft described later, 47 is a side member supporting the bearing 46, 48 A support shaft rotatably supports the rotary support 42 via a bearing 46.

The load capacity of the peeling and crushing blade 4a actually depends on the fracture resistance of the bearings 45 and 46.
The internal configuration of the peeling and crushing blades 4b and 4c and the crushing and crushing blade 3 supported on one side is not particularly shown, but is similar to the internal configuration of the peeling and crushing blade 4a shown in FIG.

Next, the operation of this embodiment will be described. The tunnel excavator body 1 is provided with a plurality of shield jacks (not shown) for propelling the tunnel excavator body 1 and a rotation drive device for rotating the head excavator 2. The head excavator 2 rotates while being supported by the bearing 10. The plurality of crushing and crushing blades 3 rotatably supported by the crushing blade support frame 31 at the tip of the head excavator 2 first contact the ground 15 exposed in the shaft, and strengthen the rock surface while rolling. Pressing by pressing force causes linear crushing and crushing and accompanying crushing.

The rock excavation by the crushing and crushing blade 3 has an excavating mechanism similar to that of a conventional shield machine, and in order to secure sufficient pressure resistance of the crushing and crushing blade 3,
Is larger than that of the peeling and crushing blades 4 (a to c), and a bearing having a load capacity of 5 times or more is used. Note that the load capacity of the bearing can be increased by increasing the bearing width. Further, as described above, since a strong pressing force acts on the crushing and crushing blade 3, by increasing the diameter thereof, it is possible to reduce the amount of rotational wear.

As the head excavator 2 rotates, a guide hole having a diameter substantially corresponding to the distance from the center of rotation to the crushing and crushing blade 3 located at the outermost periphery is formed. When the guide hole is formed to a certain depth, the outer one-side support disposed along the outer surfaces of the four main columns 21 of the head excavator 2 is peeled off as the crushing and crushing blade 3 is propelled. Among the crushing blades 4b, the cutting edge closest to the central axis contacts the outer surface of the opening of the leading hole. The position at which the edge of the peeling and crushing blade 4b comes into contact with the outer surface is more than ten mm from the end of the leading hole according to the rock quality of the bedrock of the ground 15.
The distance is set to be several tens mm. By appropriately setting the contact position of the peeling and crushing blade 4b in this way, when the sharply formed cutting edge of the peeling and crushing blade 4b cuts into the rock surface, the input of the cutting edge becomes larger than the cutting edge of the peeling and crushing blade 4b. It acts as a tensile force for peeling the rock located on the hole side of the leading hole into the leading hole.

The crushing of the rock by the tensile force, that is, the separation and crushing of the rock, is the crushing of the rock by the pressing force, ie,
Since the pressing force is about several tenths to one-tenth of that of the crushing and crushing, the bearing of the peeling and crushing blade 4b can use a bearing having a small load capacity. Can be smaller. Since the peeling and crushing blade 4b disposed near the center axis is attached to a place close to the crushing blade support frame 31, the spatial restriction on the mounting is severe, and therefore, the peeling and crushing blade 4b supported on the outer side is used. I have.

As described above, the peeling and crushing blade 4b disposed near the center axis is supported on the outer side, so that
Although the pressure resistance against the pushing back force received from the ground 15 as a reaction force to the propulsive force of the head excavator 2 is somewhat sacrificed, the position at which the edge of the peeling and crushing blade 4b contacts the exposed surface of the rock of the ground 15 is determined. The location closest to the crushing blade support frame 31 can be set. In addition, in order to withstand the above-mentioned restrictions and the pressure reaction force from the ground 15 when the tunnel excavator body 1 performs curved excavation, the angle formed between the blade surface of the peeling and crushing blade 4b and the central axis, that is, , clearance angle phi _b, as shown in FIG. 5 (a), is slightly larger set.

Thus, the peeling and crushing blade 4b attached at a position where the distance outward from the center axis and the distance backward from the tip of the head excavator 2 are each increased by a predetermined value.
The cutting edge is sequentially brought into contact with the exposed surface of the bedrock of the ground 15 and the inner portion thereof is peeled and crushed, so that the ground 15 is cut and cut into a substantially conical shape having a cylindrical step.

In this embodiment, the peeling and crushing blade mounted at a predetermined distance from the central axis is replaced with a peeling and crushing blade 4a supported on the outer side and a peeling and crushing blade 4a supported on both sides. Since the peeling and crushing blade 4a is supported on both sides, there is no particular functional difference from that of the peeling and crushing blade 4b which is supported on one side, except that it is stably supported with a large pressure resistance. In actual excavation work, since straight excavation is predominant in many cases, the peeling and crushing blade 4a, which does not have much spatial restriction on mounting, escapes in this embodiment in consideration of the pressure resistance against the pressing reaction force during straight excavation. angle phi _a, as shown in FIG. 4, it is set slightly smaller value.

The same applies to the peeling and crushing blade 4c provided near the outer periphery of the head excavator 2, but the separation and crushing blade 4b provided near the central axis is basically the same. Similarly, severe spatial constraints on attachment, an inner side support, the relief angle phi _c, as shown in FIG. 5 (b), is slightly larger set. Thus, the inner side supports the peeling crushing blades 4c, by setting the relief angle phi _c slightly greater, head position the cutting edge of the peeling crushing blades 4c comes into contact with the exposed surface of rock natural ground 15 The location can be the closest to the outer periphery of the excavator 2.

Symbols T ₁ , T ₂ , T ₃ ,..., T _n are the trajectories of the cutting edges of all the peeling and crushing blades 4 (a to c) arranged on the four main columns 21 of the head excavator 2. Are shown in the order close to the central axis. As shown in FIG. 4, each of the peeling and crushing blades 4 (a to
The bedrock of the ground 15 contacted by the cutting edge c) peels and crushes one after another, and collapses, and a step having a peel length a and a peel width b is formed. The optimum value of the ratio a / b between the separation length a and the separation width b differs depending on the rock quality of the bedrock. The cutting edge shapes of the peeling and crushing blades 4a and 4b shown in FIGS. 4 and 5 (a) are slightly rounded, but may be sharply pointed.

A plurality of crushing and crushing blades 3 and a large number of peeling and crushing blades 4
The crushed rock gravel excavated by the rotation of the head excavator 2 attached to the front of (ac) has four sub-posts 24.
Is raked by a large number of gravel intake blades 5 attached to the front surface of the head, is taken into the inside of the head excavator 2 from the gravel intake 6 between the opening plates 23, and is temporarily stored in the container 7. The crushed rock debris staying in the vicinity of the outermost peripheral portion of the head excavator 2 is taken into the inside of the head excavator 2 by the raking blade 9. The crushed rock gravel contained in the container 7 is transferred to the gravel transport device 8
Is transported to the rear of the tunnel excavator body 1.

As described above, when the peeling and crushing blades 4 (a to c) are attached to the front surface of the main support 21 of the head excavator 2 at predetermined intervals, the position changes from a position closer to the central axis to a position closer to the outer periphery. According to the above, the crushing and crushing blade 3 is disposed with a suitable peeling width b at a place receded rearward, so that the crushing and crushing blade 3 comes into contact with the bedrock of the ground 15 to cause crushing and crushing. Since the separation and crushing can be caused by a pressing force of about several tenths to tenths, a large rotational moment force is applied to the crushing and crushing blade 3 disposed within a relatively narrow range near the central axis. And a small guide hole can be easily cut. In other words, by setting the crushing blades in contact with the rock at a position away from the central axis requiring a large rotational moment force as the peeling crushing blades 4 (a to c), the ground 15 contacted with a relatively small pressing force. Can exfoliate and crush the bedrock, so that even in the case of excavation of a relatively large diameter tunnel, the rotational driving force for rotating the head excavator 2 and the propulsion force for propelling the tunnel excavator body 1 are not so large. You don't need a big one.

Therefore, there is no need for a strong shield jack or a robust structure for supporting an external force applied to the tunnel excavator body 1 and the head excavator 2, so that the weight of the machine can be reduced.
The price can be reduced. In addition, it is possible to provide a simple excavating mechanism having the same configuration as the conventional rotary excavation type without using a complicated excavating mechanism. Further, the peeling and crushing blade 4 (a to
c) Reduce the diameter of (c) and the load capacity of the bearing to reduce
Since a large number can be attached to the front of one, it is possible to improve the rock excavation efficiency. Then, the peeling and crushing blade 4b disposed near the center axis of the head excavator 2 and the peeling and crushing blade 4c disposed near the outer periphery, which are tightly restricted in terms of mounting, are supported on the outer side and the inner side, respectively. By using a single-sided support, the positions where the cutting edges contact the exposed surface of the rock of the ground 15 are set to a position closest to the crushing blade support frame 31 and a position closest to the outer periphery of the head excavator 2. Can be.

[0026]

As described above, according to the first aspect of the present invention, a plurality of crushing and crushing blades are brought into contact with the ground in a range smaller than a predetermined diameter from the rotation center of the head excavator to form a linear shape. Along with forming a small-diameter guide hole by causing crushing crushing, a plurality of rearwardly arranged from the crushing crushing blade, each having a predetermined interval in the radial direction and the rearward direction, and a plurality of sequentially attached to the outer peripheral side. Each of the peeling and crushing blades comes into contact with the ground in a range exceeding the predetermined diameter to peel and crush the ground to form a cylindrical step in the ground, and at least the center of rotation of the head excavator Alternatively, the peeling and crushing blade mounted at a position distant from the outer periphery is of a double-sided type that supports the bearing on both sides, so the propulsion force and the rotational driving force for bringing the head excavator into contact with the ground with strong force Does not require a complicated mechanism Without due, excellent lightweight and inexpensive drilling capacity is high excavation efficiency, the rotary digging edge can provide excavation machine capable of stably supported.

According to the second aspect of the present invention, the peeling and crushing blade attached to a position close to the rotation center of the head excavator is of the outer one side supporting the bearing on one side from the outer side. The position where the cutting edge of the peeling and crushing blade abuts on the exposed surface of the ground rock can be defined as the position closest to the peripheral surface position of the guide hole formed by the crushing and crushing blade. According to the third aspect of the present invention, the peeling and crushing blade attached to the position close to the outer peripheral portion of the head excavator is of an inner side that supports the bearing on one side from the inside, so that the cutting edge of the peeling and crushing blade is used. Can be the location closest to the outer circumference of the head excavator.

[Brief description of the drawings]

FIG. 1 is a front view of a tunnel excavator according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view parallel to the central axis of the tunnel excavator along section line AA in FIG. 1;

FIG. 3 is a cross-sectional view parallel to the central axis of the tunnel excavator along the section line BB in FIG. 1;

FIG. 4 is a side view of a rotary crushing blade supported on both sides.

FIG. 5 is a side view of a rotating crushing blade supported on one side.

FIG. 6 is a cross-sectional view passing through the center axis of a peeling and crushing blade supported on both sides.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Tunnel excavator main body 2 Head excavator 3 Crushing and crushing blade 4a-4c Peeling and crushing blade 5 Gravel intake blade 6 Gravel intake 7 Container 8 Gravel transport device 10, 45, 46 Bearing 11 Partition wall 15 Ground support 21 Main support 23 Opening plate 24 Sub column 31 Crushing blade support frame

 ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Minoru Tayama 650, Kandamachi, Tsuchiura-shi, Ibaraki Hitachi Construction Machinery Co., Ltd. (72) Inventor Kazunori Ueda 650, Kandamachi, Tsuchiura-shi, Ibaraki Inside the Tsuchiura Plant (72) Inventor Masaaki Miki 2-6-1 Otemachi, Chiyoda-ku, Tokyo Inside Hitachi Construction Machinery Co., Ltd. (72) Rio Iijima 2-5-2, Otemachi, Chiyoda-ku, Tokyo Inside the Hitachi Construction Machinery Co., Ltd. (72) Inventor Tsuyoshi Owada 2-6-1 Otemachi, Chiyoda-ku, Tokyo F-term inside the Hitachi Construction Machinery Co., Ltd. 2D054 BA06 BA07 BA15 BB06 CA04 CA07 DA02

Claims (3)

[Claims] 1. A head excavator having a diameter substantially equal to that of a tunnel to be excavated and rotatably supported at a tip end thereof, wherein a propulsion of an excavator body is provided in front of the head excavator. In a tunnel excavator in which a plurality of rotary excavating blades for crushing the ground in the process of rolling while contacting the ground under the force are rotatably mounted, the rotary excavating blade rotates the head excavator. A plurality of crushing and crushing blades that form a small-diameter leading hole by contacting the ground in a range smaller than a predetermined diameter from the center to form a linear crushing and crushing, and the rear of the crushing and crushing blade, Attached sequentially toward the outer peripheral side with a predetermined interval in the radial direction and the rearward direction, each abuts on the ground in a range exceeding the predetermined diameter to peel and crush the ground. Multiple exfoliations excavating to form cylindrical steps in the ground And a crushing blade, wherein the peeling crushing blade mounted at least at a position distant from the rotation center or the outer peripheral portion of the head excavator is of a double-sided type that supports a bearing on both sides. . 2. A head excavator having a diameter substantially equal to that of a tunnel to be excavated and rotatably supported at a tip end thereof, wherein a propulsion of an excavator body is provided in front of the head excavator. In a tunnel excavator in which a plurality of rotary excavating blades for crushing the ground in the process of rolling while contacting the ground under the force are rotatably mounted, the rotary excavating blade rotates the head excavator. A plurality of crushing and crushing blades that form a small-diameter leading hole by contacting the ground in a range smaller than a predetermined diameter from the center to form a linear crushing and crushing, and the rear of the crushing and crushing blade, Attached sequentially toward the outer peripheral side with a predetermined interval in the radial direction and the rearward direction, each abuts on the ground in a range exceeding the predetermined diameter to peel and crush the ground. Multiple exfoliations excavating to form cylindrical steps in the ground A crushing blade, wherein the peeling crushing blade attached to a position close to the center of rotation of the head excavator has an outer one-sided support that supports the bearing on one side from the outside. Machine. 3. A head excavator having a diameter substantially equal to that of a tunnel to be excavated and rotatably supported at a tip end thereof, and a propulsion of an excavator main body is provided in front of the head excavator. In a tunnel excavator in which a plurality of rotary excavating blades for crushing the ground in the process of rolling while contacting the ground under the force are rotatably mounted, the rotary excavating blade rotates the head excavator. A plurality of crushing and crushing blades that form a small-diameter leading hole by contacting the ground in a range smaller than a predetermined diameter from the center to form a linear crushing and crushing, and the rear of the crushing and crushing blade, Attached sequentially toward the outer peripheral side with a predetermined interval in the radial direction and the rearward direction, each abuts on the ground in a range exceeding the predetermined diameter to peel and crush the ground. Multiple exfoliations excavating to form cylindrical steps in the ground And a crushing blade, wherein the peeling crushing blade attached to a position close to an outer peripheral portion of the head excavator has an inner one-sided support that supports the bearing on one side from the inside. .