JP2023134277A - Cutter board of shield tunneling machine, and shield tunneling machine including the same - Google Patents

Abstract

To provide a cutter head of a shield tunneling machine capable of maintaining the drilling capacity on the inner circumferential side of a spoke part where scraper teeth are not placed.SOLUTION: A cutter head includes: multiple spoke parts 2b extending radially from a hub part 2a; a through hole 2e that is formed among the multiple spoke parts 2b for taking in excavated soil; an outer ring part 2d connecting the outer peripheral ends of the multiple spoke parts 2b in the extending direction; multiple leading bits 4b provided on the front of the multiple spoke parts 2b; an inclined plane TS that is formed only inward from the center in the extending direction of the multiple spoke parts 2b, which are both sides of the spoke parts 2b in the width direction that are inclined toward each other from the front to the rear of spoke part 2b; a first scraper tooth 4sa that is provided to the multiple spoke parts 2b at both outer edges in the width direction only outward from the center in the extending direction; and a second scraper tooth 4sb provided at both outer edges in the width direction at the outer peripheral ends in the extending direction of the multiple spoke parts 2b.SELECTED DRAWING: Figure 4

Description

The present invention relates to a shield tunneling machine and a shield tunneling machine including the shield tunneling machine.

A shield tunneling machine is a device that forms an excavation hole in a rock by pushing a cutter board provided on the front of the device body against a face of a rock and moving forward while rotating it.

Shield tunneling machines include mud pressure shield tunneling machines and mud water type shield tunneling machines. The former type of shield excavator has a structure that stabilizes the face by injecting additives into the chamber and turning the excavated soil into mud (fluidization) and applying a predetermined pressure. By filling the space between the face and the bulkhead, and injecting and kneading additives into this, the soil becomes mud (a mixture of gravel and additives) with high fluidity and water-stopping properties, and the earth pressure stabilizes the face. It is a shield machine that digs while digging. Note that the earth and sand mixed with the additive in the chamber is taken into a screw conveyor and discharged from the rear of the device body. The latter shield excavator has a structure in which the face is stabilized by applying a predetermined pressure to the muddy water in the chamber, and the excavated soil is fluidly transported by circulating the muddy water.

Here, the cutter board of the mud pressure shield excavator has a hub part located at the center of rotation, a plurality of spoke parts extending radially from the hub part, and an outer peripheral end in the extending direction of the plurality of spoke parts. and a connecting outer peripheral ring portion. Further, a through hole is formed between the spoke parts for taking in earth and sand excavated by the cutter board into a chamber formed behind the cutter board.

Each spoke section is equipped with various excavating means such as roller cutters, leading bits, scraper teeth, etc. The roller cutter is arranged at the front of each spoke part, and mainly crushes cobblestones, boulders, etc. (hereinafter sometimes simply referred to as "cobblestones"). A plurality of leading bits are arranged on the front surface of each spoke portion, and perform leading excavation and protect the scraper teeth. Furthermore, a plurality of scraper teeth are arranged along the extending direction of each spoke part at both outer edges in the width direction of each spoke part, that is, at the outer peripheral corner of the excavated earth and sand intake port, and scraper teeth are used to excavate the ground. At the same time, excavated earth and sand are taken into the chamber (see, for example, Patent Documents 1 to 5).

Japanese Patent Application Publication No. 2012-122257 JP2012-122258A Japanese Patent Application Publication No. 2012-122259 Japanese Patent Application Publication No. 2012-122260 Japanese Patent Application Publication No. 10-140984

By the way, in the mud pressure shield excavator, if there is a boulder larger than the maximum diameter that can be taken in through the through hole formed in the cutter board, the boulder is crushed with a bit and then taken in. This is because if a cobblestone that cannot be transported by the screw conveyor is taken in, it cannot be crushed in the chamber, so it remains while being agitated in the chamber until it is worn down to a diameter that can be transported by the screw conveyor. This is because this may lead to damage to the stirring rod, torque arm, etc. Therefore, the maximum diameter of the boulders taken in from the cutter board needs to be smaller than the diameter that can be transported by the screw conveyor.

When using a mud pressure shield excavator, when excavating a gravel layer with a very high gravel ratio and containing boulders, large-diameter boulders are buried in the ground on the inner circumferential side of the cutter plate (inward from the center in the extending direction of the spoke part). If the boulder is removed from the face ground, it will roll toward the outer periphery of the spoke part (from the center in the extending direction of the spoke part) where there is a through hole large enough to take the boulder in. Moving. Then, the boulders collide with the spokes and the bits attached to the spokes many times before they are taken in through the through-holes on the outer circumferential side, leading to accelerated wear and damage of the bits and spokes.

This tendency is particularly greater in relatively small-diameter shield tunneling machines with a shield diameter of about 2000 mm to 4500 mm than in relatively large-diameter shield tunneling machines with a shield diameter of 6000 mm or more.

Here, if the scraper teeth protruding from the side surface of the spoke part are arranged only on both outer edges in the width direction on the outer circumference side of the spoke part, and not on the inner circumference side, the penetration formed on the inner circumference side can be removed. Since the maximum diameter of the boulder that can be taken into the hole is increased, the above-mentioned wear and damage of the bit and spoke parts is suppressed.

However, on the inner peripheral side of the spoke portion where the scraper teeth are not arranged, there is a possibility that the ability to excavate the ground may be reduced.

The present invention has been made from the above-mentioned technical background, and is a cutter board of a shield excavator, in which the ability to excavate the ground on the inner circumferential side of the spoke portion where the scraper teeth are not disposed is not impaired. The purpose is to provide technology.

In order to solve the above problems, a cutter board for a shield excavator according to the present invention as set forth in claim 1 includes a hub portion located at the center of rotation, a plurality of spoke portions extending radially from the hub portion, and a plurality of spoke portions extending radially from the hub portion. A through hole formed between the spoke parts for taking in excavated earth and sand, an outer peripheral ring part connecting the outer peripheral ends of the plurality of spoke parts in the extending direction, and a peripheral ring part provided on the front surface of the plurality of spoke parts. a plurality of leading bits; and a plurality of spoke parts formed only inwardly from the central part in the extending direction of the plurality of spoke parts, and inclined in a direction in which the spoke parts approach each other from the front to the rear of the spoke part in the width direction of the spoke part. a first scraper tooth provided at both outer edges in the width direction only outward from the central part in the extending direction of the plurality of spoke parts; and an extension of the plurality of spoke parts. and second scraper teeth provided at both outer edges in the width direction at the outer peripheral end in the direction.

A cutter board for a shield tunneling machine according to a second aspect of the present invention is characterized in that, in the first aspect of the invention, a wear-resistant steel plate is attached to the inclined surface.

The cutter board for a shield excavator according to the present invention according to claim 3 is characterized in that, in the invention according to claim 2, the wear-resistant steel plate is coated to prevent adhesion of excavated earth and sand. Features.

A cutter board for a shield excavator according to the present invention according to claim 4 is characterized in that, in the invention according to claim 1, an adhesion prevention plate for preventing excavated soil from adhering to the slope is attached to the slope. Features.

A cutter board for a shield excavator according to the present invention according to claim 5 is characterized in that, in the invention according to claim 1, the inclined surface is coated to prevent adhesion of excavated earth and sand. shall be.

A cutter board for a shield excavator according to the present invention according to claim 6 is the cutter board for a shield tunneling machine according to any one of claims 1 to 5 above, in which the cutter board is arranged only inwardly from the central part in the extending direction of the plurality of spoke parts. It is characterized in that it further includes a protection member that is provided and protects the inside from the center part in the extending direction of the spoke part.

In the cutter board for a shield excavator according to the present invention according to claim 7, in the invention according to claim 6, the protection member includes wear-resistant steel plates installed at both outer edges in the width direction of the spoke portion, and It is characterized in that it is at least one of wear-resistant steel plates installed on the front surface of the spoke portion.

In the cutter board for a shield excavator according to the present invention according to claim 8, in the invention according to claim 6 or 7, the protection member is located inside the spoke portion from the center in the extending direction of the spoke portion. It is characterized by a built-up welded portion formed on the entire side surface in the width direction of the front plate.

A shield tunneling machine according to the present invention according to claim 9 is characterized in that the cutter board according to any one of claims 1 to 8 is rotatably provided on the front surface of the equipment main body.

According to the present invention, both side surfaces in the width direction only on the inner circumferential side of each spoke portion are sloped surfaces that are inclined in a direction that approaches each other from the front to the rear of the spoke portion. As a result, the ground on the face surface, which has been broken into grooves by the leading bit on the inner circumferential side, is scooped out by the spokes on the inner circumferential side and taken into the machine.

Therefore, even on the inner peripheral side of the spoke portion where the scraper teeth are not arranged, the ability to excavate the earth is not impaired.

1 is a configuration diagram showing the inside of a mud pressure shield excavator according to an embodiment of the present invention as seen from the side; FIG. FIG. 2 is a front view of the cutter head of the mud pressure shield excavator of FIG. 1; FIG. 3 is a side view of the cutter head of FIG. 2 viewed from the direction of arrow A1. 3 is a sectional view taken along arrow X in FIG. 2. FIG. FIG. 5 is an enlarged cross-sectional view of the Z section in FIG. 4. FIG. FIG. 3 is a sectional view taken from arrow Y in FIG. 2. FIG.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment as an example of this invention will be described in detail based on drawing. In addition, in the drawings for explaining the embodiments, the same components are designated by the same reference numerals in principle, and repeated explanation thereof will be omitted.

FIG. 1 is a configuration diagram showing the inside of the mud pressure shield excavator of this embodiment from the side, FIG. 2 is a front view of the cutter head of the mud pressure shield excavator of FIG. 1, and FIG. 3 is a cutter of the cutter head of the mud pressure shield excavator of FIG. 4 is a sectional view of the head seen from arrow A1 in FIG. 2, FIG. 5 is an enlarged sectional view of section Z in FIG. FIG.

The mud pressure shield excavation machine (shield excavation machine) 1 of the present embodiment has imperviousness and plastic flow generated by injecting and mixing additives into earth and sand excavated by a cutter head (cutter board) 2. The chamber between the cutter head 2 and the equipment body 3 is filled with mud having a property of being able to deform and move freely. This is a device that constructs an excavation pit against the ground.

This mud-earth pressure shield excavator 1 is particularly suitable for excavating a sand and gravel layer with cobbles mixed with boulders or a rock layer including a cobblestone layer. May be applied to gravel layers.

Note that the outer diameter of the excavation of the mud pressure shield excavator 1 is, for example, about 4500 mm. Further, the length of the mud pressure shield excavator 1 is, for example, about 6400 mm. Further, the operation of the mud pressure shield excavator 1 is controlled by an operator in a driver's room in a following truck (not shown) disposed behind it.

The cutter head 2 is a member for excavating a face of the earth, and is installed on the front surface of the device main body 3 so as to be rotatable along the circumferential direction of the device main body 3. This cutter head 2 employs, for example, a disc-shaped spoke type. That is, as shown in FIG. 2, the cutter head 2 includes a hub portion 2a located at the center of rotation, six spoke portions 2b extending radially from the hub portion 2a toward the outer periphery, and an extension of each spoke portion 2b. An intermediate ring part 2c that connects midway parts in the direction, an outer ring part 2d that connects the tips of each spoke part 2b, and a penetration hole formed between each spoke part 2b to take excavated earth and sand into the chamber 6. and a hole 2e.

A center bit 4a is attached to the hub portion 2a of the cutter head 2. Note that other excavating members such as a cone head type roller bit may be attached to the hub portion 2a.

As shown in the figure, each spoke portion 2b has a dimension in the width direction (rotation direction of the cutter head 2) at a central portion in the extending direction of the spoke portion 2b (here, slightly smaller than the mounting position of the intermediate ring portion 2c). It is formed so that it becomes thinner as it approaches the hub part 2a from the inner side (hereinafter referred to as the "inner circumferential side") (closer to the hub part 2a), and from the outer side (hereinafter referred to as the "outer circumferential side") from the central part in the extending direction of the spoke part 2b. ) are formed so that the dimensions in the width direction are the same.

This is achieved by forming the spoke part 2b so that it gradually becomes wider from the hub part 2a on the inner peripheral side of the spoke part 2b, thereby ensuring the strength and stability of the spoke part 2b while ensuring the opening area of the through hole 2e as much as possible. This is because it is possible to achieve In other words, if the widthwise dimension of the inner circumferential side of the spoke portion 2b is made thinner, the opening area of the through hole 2e can be made wider, but the strength will decrease.On the other hand, if the opening area of the through hole 2e is made narrower, the strength will be improved, but the strength will be reduced. This is because the opening area of the hole 2e is reduced.

Further, by forming the spoke portions 2b so that the dimensions in the width direction are the same on the outer peripheral side, the opening area of the through hole 2e, in other words, the opening ratio can be increased.

In addition, in this embodiment, the central part of the spoke part 2b in the extending direction is located slightly closer to the hub part 2a than the mounting position of the intermediate ring part 2c, but it is located at the same position as the mounting position of the intermediate ring part 2c. Alternatively, the mounting position may be closer to the outer ring portion 2d than the mounting position of the intermediate ring portion 2c. Furthermore, the central portion of the spoke portion 2b in the extending direction does not need to be exactly half the length of the spoke portion 2b, and may be approximately half the length of the spoke portion 2b.

Furthermore, in this embodiment, the spoke portions 2b are formed so that the widthwise dimensions become thinner as they approach the hub portion 2a on the inner peripheral side, and the widthwise dimensions are the same from the center portion to the outside. However, it may be formed to have the same width over the entire length of the spoke portion 2b, or may be formed to become thinner as it approaches the hub portion 2a over the entire length of the spoke portion 2b.

Each spoke portion 2b is equipped with a leading bit 4b, a scraper tooth 4s, and a wear-resistant steel plate (protective member) 4t. In this embodiment, the height of the leading bit 4b (height from the surface of the spoke part 2b) is 150 mm, the height of the scraper tooth 4s is 100 mm, and the amount of protrusion (the amount of protrusion from the side surface of the spoke part 2b) is 100 mm. It becomes. In addition to the leading bit 4b, other excavating members such as a roller bit may be attached to the front surface of the spoke portion 2b.

The leading bit 4b not only crushes boulders etc. and excavates the ground in advance, but also has the role of protecting the scraper tooth 4s.As shown in FIG. A plurality of them are installed in regular rows on opposite sides. Each leading bit 4b has a planar shape, for example, a substantially rectangular shape, and is arranged with its long side along the width direction of the spoke portion 2b.

Note that in this embodiment, the leading bits 4b adjacent to each other in the rotational direction of the cutter head 2 are arranged on different rotational trajectories; however, the present invention is not limited to this, and the preceding bits 4b may be arranged on the same rotational trajectory. You may.

The scraper teeth 4s have the role of excavating the ground and taking the excavated earth and sand into the chamber 6 (FIG. 1), and are provided at both outer edges in the width direction only on the outer circumferential side of each spoke portion 2b. It consists of a first scraper tooth 4sa and a second scraper tooth 4sb provided at both outer edges in the width direction at the outer peripheral end in the extending direction of each spoke portion 2b. As will be described later, the attachment position of the first scraper tooth 4sa differs depending on the spoke part 2b, but the first scraper tooth 4sa attached closest to the hub part 2a (in FIG. The radially outer side of the first scraper tooth 4sa attached to the spoke portion 2b at positions corresponding to 12 o'clock and 6 o'clock corresponds to the outer peripheral side of the spoke portion 2b.

In this embodiment, the attachment positions of the first scraper teeth 4sa of adjacent spoke portions 2b are shifted from each other in the radial direction of the cutter head 2. Specifically, in order to prevent the trajectories of the first scraper teeth 4sa from being different from each other when the cutter head 2 rotates and leaving an unexcavated area of the ground as a whole, in FIG. and the first scraper tooth 4sa installed at the position corresponding to 6 o'clock, the first scraper tooth 4sa installed at the position corresponding to 2 o'clock and 8 o'clock, and the first scraper tooth 4sa installed at the position corresponding to 4 o'clock and 10 o'clock. The first scraper teeth 4sa are arranged alternately.

In addition, in this embodiment, two types of second scraper teeth 4sb with different lengths are provided, and in FIG. The second scraper tooth 4sb is longer than the second scraper tooth 4sb installed at other positions, so that the trajectory when the cutter head 2 rotates corresponds to 4 o'clock and 10 o'clock on the clock face. The trajectory slightly overlaps with the trajectory of the first scraper tooth 4sa on the outer peripheral side.

By arranging the first scraper teeth 4sa and the second scraper teeth 4sb in this way, the ground located on the outer peripheral side of the cutter head 2 is evenly excavated.

As shown in FIGS. 4 and 6, both side surfaces in the width direction only on the inner peripheral side of each spoke portion 2b are sloped surfaces TS that are inclined in a direction from the front to the rear of the spoke portion 2b toward each other. It has become. As shown in the figure, in this embodiment, the inclination angle of the inclined surface TS (the angle formed by the inclined surface TS and a line perpendicular to the front plate 2ba of the spoke portion 2b) is 5°. Such an inclined surface TS has the same function as the scraper teeth 4s on the outer circumferential side described above, and is excavated so that the ground on the face surface crushed into grooves by the leading bit 4b is scooped out and the chamber 6 is taken within. Note that the inclination angle of the inclined surface TS does not need to be 5° and can be set freely.

Here, as shown in FIGS. 4 and 6, a wear-resistant steel plate 4t is attached to the slope TS to protect the slope TS, and prevents wear and damage of the spoke portion 2b due to ground excavation. are doing. Note that the wear-resistant steel plate 4t attached to the inclined surface TS may be coated with a powder or liquid anti-sediment adhesion agent. If such coating treatment is performed to prevent the adhesion of excavated earth and sand, the excavation amount of earth and sand on the face surface will not decrease due to the earth and sand adhered to the slope surface TS, and the excavation efficiency will not deteriorate.

Further, instead of the wear-resistant steel plate 4t, an adhesion prevention plate for preventing excavated soil from adhering may be attached to the inclined surface TS. Alternatively, instead of attaching the wear-resistant steel plate 4t or the adhesion prevention plate to the inclined surface TS, a coating treatment to prevent the adhesion of excavated earth and sand may be directly applied. As mentioned above, even if an anti-adhesion plate is attached to the slope TS or an anti-adhesion coating is applied, the amount of earth and sand excavated on the face surface will be reduced due to the sediment adhering to the slope TS, resulting in a reduction in excavation. Efficiency will no longer deteriorate.

Furthermore, in this embodiment, as shown in FIGS. 2, 4, and 5, both outer edges in the width direction on the inner circumferential side of each spoke portion 2b, and the front surface of the inner circumferential side of each spoke portion 2b (in detail, A wear-resistant steel plate 4t is attached to the surface of the front plate 2ba of the spoke portion 2b via a mounting plate 4v. By providing such a wear-resistant steel plate 4t, both outer edges and surfaces in the width direction on the inner circumferential side of each spoke portion 2b are protected, thereby preventing wear and damage of the spoke portion 2b due to ground excavation.

In the present embodiment, the wear-resistant steel plate 4t is attached to both outer edges in the width direction and the front surface of the inner circumferential side of each spoke portion 2b, but it may be attached to either the outer edges in the width direction or the front surface. may have been done. Further, the wear-resistant steel plate 4t may be mounted directly on the spoke portion 2b without using the mounting plate 4v.

Furthermore, as shown in FIGS. 4 to 6, a built-up welded portion (protective member) 4w is formed on the inner peripheral side of each spoke portion 2b over the entire widthwise side surface of the front plate 2ba of the spoke portion 2b. ing. This improves the wear resistance of the inner peripheral side of the spoke portion 2b during ground excavation.

Here, the maximum diameter for taking in boulders in the through hole 2e is determined by the size (diameter) of the screw conveyor 10, but in the mud pressure shield excavator 1 of this embodiment, cobbles with a diameter of about 700 mm x 600 mm are used. The through hole 2e formed in the cutter head 2 is sized to accommodate cobblestones with a maximum diameter of 700 mm.

This is because if a cobblestone of a size that cannot be transported by the screw conveyor 10 is taken in from the through hole 2e, it cannot be crushed in the chamber 6, so it is transported by the screw conveyor 10 while being stirred in the chamber 6. It will remain until it is worn down to the desired diameter. In that case, the kneading blades 15, 16 (described later), etc. may be damaged, so the maximum diameter of the cobbles taken into the chamber 6 needs to be smaller than the diameter that can be transported by the screw conveyor 10.

Additive material injection ports 5a are provided in the hub portion 2a and the spoke portions 2b. The additive injection port 5a is a component for injecting a mud material such as a bentonite-based additive toward the front face of the cutter head 2. Note that for the additives injected from each of the additive material injection ports 5a, a cellular material may be used instead of the bentonite-based additive, or both a bentonite-based additive and a cellular material may be used. good.

The earth and sand excavated by the cutter head 2 is taken into a chamber 6 (see FIG. 1), which will be described later, through the through hole 2e. By regulating the opening area of the boulder, the size of the boulder taken in through the through hole 2e is regulated. In addition, when the excavation outer diameter of the mud pressure shield excavator 1 is small (for example, 2000 mm), the installation of the intermediate ring portion 2c can be omitted.

A plurality of outer circumferential bits (bits) 4c are installed in line on the front surface of the outer circumferential ring portion 2d on the face side. This outer bit 4c also has a height of 150 mm. Note that the heights of the outer peripheral bits 4c adjacent to each other in the rotational direction of the cutter head 2 can be made to be different so as to repeat elevations along the rotational direction of the cutter head 2. In this way, the impact and load applied to the outer bit 4c can be dispersed, the durability of the outer bit 4c can be improved, and the replacement period of the outer bit 4c of the cutter head 2 can be extended. Moreover, by changing the height of the outer circumferential bit 4c on the same rotational trajectory, it is possible to cut down boulders, etc. on the face in an excellent manner.

Further, on the outer peripheral surface of the outer peripheral ring portion 2d, for example, two copy bits 4d are provided at opposite positions. This copy bit 4d has the role of performing over-digging during construction of a sharp curve, controlling the attitude of the mud pressure shield excavator 1, and the like.

As shown in FIG. 1, the main body 3 includes a front body plate 3a of a girder portion and a rear body plate 3b of a tail portion behind the front body plate 3a. The front body plate 3a and the rear body plate 3b are formed of, for example, cylindrical steel plates, and are members that form the outer shape of the device body 3 and form a hollow space inside the device body 3. The front body plate 3a and the rear body plate 3b are engaged with each other by inserting the spherical bearing portion at the tip of the rear body plate 3b in contact with the inner peripheral surface of the front body plate 3a on the rear end side of the front body plate 3a. has been done.

On the front side of the front fuselage plate 3a, a partition wall 7 that divides the hollow space inside the equipment main body 3 into a face side and an inside of the machine is provided at a position retreating inward from the front surface of the equipment main body 3. A chamber 6 is provided on the face side of the partition wall 7 (that is, between the cutter head 2 and the partition wall 7), and on the machine side of the partition wall 7, an additive injection part 5b, a cutter drive body 8, and a bending jack are provided. 9a, a shield jack 9b, a screw conveyor 10, and an earth pressure detection section (not shown).

The additive injection part 5b is a device that injects additives toward the outside of the device main body 3 or into the chamber 6. 7 near the outer periphery. The additive material injected from the additive material injection part 5b is, for example, a muddy soil material such as a bentonite-based additive material. Note that, as the additive injected from the additive injection part 5b, a cellular material may be used instead of the bentonite-based additive, or both the bentonite-based additive and the cellular material may be used.

The chamber 6 is a space into which earth and sand excavated by the cutter head 2 are taken. In this chamber 6, a mixing blade 15 having a cylindrical shape or the like that protrudes into the chamber 6 is provided on the front surface of the partition wall 7, while a cylindrical or other kneading blade 15 that protrudes into the chamber 6 is provided on the back surface of the cutter head 2. A kneading blade 16 is provided. These mixing blades 15 and 16 are offset from each other in the radial direction of the cutter head 2, and when the cutter head 2 rotates, they stir the earth and sand that has entered the chamber 6 and the additive material that has been injected into the chamber 6. It has the role of mixing.

The cutter drive body 8 is a drive source that rotates the cutter head 2. Here, an intermediate support drive method is exemplified as the cutter drive method, and as shown in FIG. A plurality of them are arranged in a line along the circumferential direction of 2.

The bending jack 9a is a device that connects the front body plate 3a and the rear body plate 3b and also corrects the direction of propulsion of the mud pressure shield excavator 1. As shown in FIG. A plurality of them are arranged in a line along the circumferential direction of the mud pressure shield excavator 1 at positions straddling the boundary between the body plate 3a and the rear body plate 3b. By supplying pressure oil to this bent jack 9a and propelling the mud earth pressure shield excavator 1 with the front body plate 3a and the rear body plate 3b bent in a predetermined direction and angle, the mud earth pressure shield It is possible to control the direction of propulsion of the excavator 1.

The shield jack 9b is a device that generates a propulsive force for moving the mud pressure shield excavator 1 forward by generating a reaction force on the segment SG installed at the rear of the device main body 3. As shown in FIG. As shown in FIG. 3, a plurality of them are arranged in a line along the circumferential direction of the mud pressure shield excavator 1 at a position straddling the boundary between the front body plate 3a and the rear body plate 3b in the main body 3.

The screw conveyor 10 is a device for discharging the earth and sand taken into the chamber 6 to the outside of the machine, and as shown in FIG. It is provided so as to continuously extend diagonally upward from the earth and sand intake end 10a toward the discharge end 10b, which is located at a position slightly higher than the center of the equipment main body 3 in the height direction at the rear of the equipment main body 3. There is.

As the screw conveyor 10, for example, a ribbon-type screw conveyor is used, in which a spiral blade 10c without a rotating shaft is provided inside a tube. In the case of a screw conveyor with a rotating shaft, it is easily blocked by boulders, whereas in the case of the ribbon-type screw conveyor 10, the maximum diameter of the boulders that can be conveyed can be greater than the radius of the conveying path, and the rotating shaft can be blocked. It is also possible to transport cobblestones that are too large to be transported using a screw conveyor. As a result, the mud pressure shield excavator 1 of the present embodiment is configured to be able to take in boulders and the like of a size that can be discharged by the screw conveyor 10 into the chamber 6 without crushing them.

An earth discharge pipe (not shown) is connected to the discharge end 10b of the screw conveyor 10, and the earth and sand conveyed to the discharge end 10b of the screw conveyor 10 is conveyed to a cart or the like through the earth discharge pipe. It has become.

The earth pressure detection part is a sensor part that converts the pressure caused by the mud in the chamber 6 into an electric signal via a strain gauge, and is provided with its earth pressure detection surface facing into the chamber 6. The mud pressure shield excavator 1 advances the excavation process while maintaining the stability of the face by managing the mud pressure in the chamber 6 detected by the earth pressure detection part to be within a predetermined value range. It looks like this.

Next, a mud pressure shield construction method using the mud pressure shield excavator 1 shown in FIG. 1 will be explained. Here, the target for excavation is a ground consisting of a gravel layer with a very high gravel ratio and containing boulders.

When excavating such a ground, the mud pressure shield excavator 1 of the present embodiment constructs an excavation hole underground by pushing the main body 3 of the device forward while pressing the cutter head 2 against the face and rotating it.

During this excavation work, an additive is added to the earth and sand excavated by the cutter head 2, and the earth and sand and the additive are stirred and mixed by the rotation of the cutter head 2 and the operation of the mixing blade 16 that follows the rotation. Converts excavated soil into mud with plastic fluidity and impermeability. Then, the chamber 6 and the screw conveyor 10 are filled with the mud, the filled mud is pressurized by the propulsive force of the shield jack 9b to generate mud pressure, and this mud pressure is made to oppose the earth pressure of the face. to maintain the stability of the face. Further, for example, the rotational speed of the cutter head 2 is kept constant, the extension speed of the shield jack 9b and the rotational speed of the screw conveyor 10 are adjusted, and the mud pressure in the chamber 6 is measured by the earth pressure detection section and becomes constant. This will maintain the stability of the face.

Bentonite-based additives (sludge materials) added as additives have the effect of increasing the plastic fluidity and impermeability of the soil, and also envelop gravel such as crushed boulders and cobbles together with the excavated soil. It has the effect of improving the integrity of the excavated soil and gravel so that the gravel does not separate from the excavated soil.

Here, if the maximum diameter of the boulder that can be taken in through the through hole 2e on the outer peripheral side of the cutter head 2 is larger than that on the through hole 2e on the inner peripheral side, the boulder cannot be taken in through the through hole 2e on the inner peripheral side. The boulders move toward the outer periphery of the spoke portion 2b and are taken in through the through holes 2e on the outer periphery. During this time, the boulders repeatedly collide with the spoke portion 2b and the leading bit 4b attached to the spoke portion 2b, accelerating wear and damage of the leading bit 4b and the spoke portion 2b.

On the other hand, in the mud pressure shield excavator 1 of the present embodiment, as described above, the scraper teeth 4s protruding from the side surface of each spoke part 2b are not provided on the inner peripheral side of each spoke part 2b. Therefore, the maximum diameter of the boulder that can be taken in by the through hole 2e is the same between the inner circumferential side and the outer circumferential side of the cutter head 2. Therefore, if a large-diameter boulder that can be taken in through the through hole 2e is on the ground on the inner side of the cutter head 2, that boulder will be taken in through the through hole 2e on the inner side after coming off the face ground. It is sent into the chamber 6.

At this time, both side surfaces in the width direction only on the inner peripheral side of each spoke part 2b are inclined surfaces TS that are inclined in a direction in which they approach each other from the front to the rear of the spoke part 2b. As a result, the inclined surface TS has the same function as the scraper tooth 4s on the outer circumferential side, so that the ground of the face surface broken into grooves by the leading bit 4b on the inner circumferential side is the spoke part 2b on the inner circumferential side. It is scooped up and taken into the chamber 6 (in other words, inside the machine).

Therefore, even on the inner peripheral side of the spoke portion 2b where the scraper teeth 4s are not arranged, the ability to excavate the earth is not impaired.

As above, the invention made by the present inventor has been specifically explained based on the embodiments, but the embodiments disclosed in this specification are illustrative in all respects, and are limited to the disclosed technology. It should be considered that it is not a thing. In other words, the technical scope of the present invention should not be construed in a limited manner based on the description of the embodiments described above, but should be construed solely in accordance with the description of the claims, and the scope of the claims This invention includes techniques equivalent to the techniques described in , and all changes without departing from the gist of the claims.

For example, in the embodiment described above, a case was explained in which a ribbon screw type screw conveyor was used, but the invention is not limited to this and various modifications are possible. For example, a screw conveyor that combines a ribbon type and a shaft type may also be used.

In the above explanation, the present invention was applied to a mud pressure shield excavator with an intermediate support drive method, but the present invention is not limited to this. It also applies to other shield tunneling machines such as tunneling machines.

1 Mud earth pressure shield excavation machine (shield excavation machine)
2 Cutter head (cutter board)
2a Hub portion 2b Spoke portion 2c Intermediate ring portion 2d Outer ring portion 2e Through hole 4a Center bit (bit)
4b Leading bit (bit)
4c Outer bit (bit)
4s Scraper tooth 4sa First scraper tooth 4sb Second scraper tooth 4t Wear-resistant steel plate (protective member)
4w Overlay welding part (protective member)
6 Chamber 7 Partition wall 10 Screw conveyor TS Inclined surface

In order to solve the above problems, a cutter board for a shield excavator according to the present invention as set forth in claim 1 includes a hub portion located at the center of rotation, a plurality of spoke portions extending radially from the hub portion, and respective spoke portions. A through hole formed between the spoke parts and for taking in excavated earth and sand, an outer peripheral ring part connecting the outer peripheral ends of the plurality of spoke parts in the extending direction, and a peripheral ring part provided on the front surface of the plurality of spoke parts. The plurality of leading bits are formed only on the inner side from the center position of the distance from the center of rotation of the cutter board in the front view in the extending direction of the plurality of spoke parts to the outer end of the spoke part, and on the face side. An inclined surface that is both side surfaces in the width direction of a certain spoke part that slopes toward each other from the front to the rear of the spoke part, and only the outside from the central position in the extending direction of the plurality of spoke parts. a first scraper tooth provided on both outer edges in the width direction of the plurality of spoke parts ; and a second scraper tooth provided on both outer edges in the width direction at outer peripheral ends in the extending direction of the plurality of spoke parts. and the pitch of the preceding bit arranged inwardly from the central position of the plurality of spoke parts with respect to the extending direction of the spoke part is equal to the pitch of the spoke part of the preceding bit arranged outwardly from the central position. The pitch is narrower than the pitch in the extending direction, and either a wear-resistant steel plate coated with a coating to prevent excavated soil from adhering is attached to the slope, or a coating is applied to prevent excavated soil from adhering to the slope. It is characterized by being processed .

In the cutter board for a shield excavator according to the present invention according to claim 2, in the invention according to claim 1 , an angle formed by a line perpendicular to the front plate of the spoke portion and the slope is 5°. It is characterized by:

The cutter board of the shield tunneling machine according to the present invention according to claim 3 is provided only on the inner side from the central part in the extending direction of the plurality of spoke parts in the invention according to claim 1 or 2. It is characterized in that it further includes a protection member that protects the inside from the central part in the extending direction.

In the cutter board for a shield excavator according to the present invention according to claim 4 , in the invention set forth in claim 3 , the protection member is arranged so that the cutter board is located inward from the central position in the extending direction of the spoke portion when viewed from the front. A wear-resistant steel plate is provided between the edges on both sides in the width direction and the leading bit .

In the cutter board for a shield excavator according to the present invention according to claim 5 , in the invention according to claim 3 , the protection member is located in front of the spoke portion inward from the central position in the extending direction of the spoke portion. It is characterized by a built-up weld formed over the entire side surface in the width direction of the face plate.

A shield excavator according to the present invention according to claim 6 is characterized in that the cutter board according to any one of claims 1 to 5 is rotatably provided on the front surface of the equipment main body.

As shown in the figure, each spoke portion 2b has a dimension in the width direction (rotation direction of the cutter head 2) that is outside the spoke portion 2b from the rotation center in the front view of the cutter head 2 in the extending direction of the spoke portion 2b. From the center position of the distance to the end (here, slightly closer to the hub part 2a than the mounting position of the intermediate ring part 2c) to the inside (hereinafter referred to as the "inner circumferential side"), it becomes thinner as it approaches the hub part 2a. The spoke portions 2b are formed so that the dimensions in the width direction are the same on the outside from the center position in the extending direction (hereinafter referred to as the "outer circumferential side").

In this embodiment, the center position of the spoke portion 2b in the extending direction is slightly closer to the hub portion 2a than the attachment position of the intermediate ring portion 2c, but is at the same position as the attachment position of the intermediate ring portion 2c. Alternatively, the mounting position may be closer to the outer ring portion 2d than the mounting position of the intermediate ring portion 2c.

Furthermore, in this embodiment, the spoke portions 2b are formed so that their widthwise dimensions become narrower as they approach the hub portion 2a on the inner circumferential side, and are formed so that their widthwise dimensions are the same outward from the center position. However, it may be formed to have the same width over the entire length of the spoke portion 2b, or may be formed to become thinner as it approaches the hub portion 2a over the entire length of the spoke portion 2b.

The shield jack 9b is a device that generates a propulsive force for moving the mud pressure shield excavator 1 forward by generating a reaction force on the segment SG installed at the rear of the device main body 3. As shown in FIG. A plurality of them are arranged in a line along the circumferential direction of the mud pressure shield excavator 1 at a position straddling the boundary between the front body plate 3a and the rear body plate 3b in the main body 3.

Claims (9)

A hub part located at the center of rotation,
a plurality of spoke portions extending radially from the hub portion;
a through hole formed between the plurality of spoke parts and for taking in excavated soil;
an outer circumferential ring portion that connects outer circumferential ends of the plurality of spoke portions in the extending direction;
a plurality of leading bits provided on the front surface of the plurality of spoke parts;
An inclined surface that is formed only on the inner side from the central part in the extending direction of the plurality of spoke parts, and is both side surfaces in the width direction of the spoke part, which slopes in a direction in which the spoke parts approach each other from the front to the rear. and,
first scraper teeth provided at both outer edges in the width direction only outward from the central portion in the extending direction of the plurality of spoke portions;
second scraper teeth provided at both outer edges in the width direction at the outer peripheral ends in the extending direction of the plurality of spoke parts;
A cutter board for a shield excavator, characterized in that it has. A wear-resistant steel plate is attached to the inclined surface.
A cutter board for a shield excavator according to claim 1, characterized in that: The wear-resistant steel plate is coated to prevent excavation soil from adhering to it.
A cutter board for a shield excavator according to claim 2, characterized in that: An adhesion prevention plate is attached to the slope to prevent excavated soil from adhering to the slope.
A cutter board for a shield excavator according to claim 1, characterized in that: The slope surface is coated to prevent excavated soil from adhering to it.
A cutter board for a shield excavator according to claim 1, characterized in that: further comprising a protection member that is provided only on the inner side of the central part in the extending direction of the plurality of spoke parts and protects the inner side from the central part in the extending direction of the plurality of spoke parts;
A cutter board for a shield excavator according to any one of claims 1 to 5, characterized in that: The protection member is
At least one of a wear-resistant steel plate installed on both outer edges in the width direction of the spoke part, and a wear-resistant steel plate installed on the front surface of the spoke part,
A cutter board for a shield excavator according to claim 6. The protection member is
A built-up welding portion formed on the entire side surface in the width direction of the front plate of the spoke portion inward from the central portion in the extending direction of the spoke portion,
A cutter board for a shield excavator according to claim 6 or 7, characterized in that: The cutter board according to any one of claims 1 to 8 is rotatably provided on the front surface of the device main body.
A shield excavator characterized by:

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