TWI807733B - Cutter board of shield excavator and shield excavator including the same - Google Patents

Abstract

An objective of the present invention is to obtain a cutter head for shield excavator in which excavation ability does not decrease in an inner peripheral side of a spoke where scraper teeth are not arranged. A cutter board of shield excavator of the present invention includes: a plurality of spoke portions 2b extending radially from a hub portion 2a; a through hole 2e formed between the plurality of spokes portions 2b for taking in excavated soils and sands; an outer peripheral ring portion 2d connecting the outer peripheral ends of the plurality of spoke portions 2b in the extension direction; a plurality of leading bits 4b provided on the front surfaces of the plurality of spoke portions 2b; an inclined surface TS which are both side surfaces in the width direction of the spoke portions 2b, formed only from the central portion of the plurality of spoke portions 2b toward the inner side in the extension direction, and inclined in the direction of approaching each other from the front to the rear of the spoke portion 2b; a first scraper tooth 4sa provided at two outer edge portions in the width direction of the plurality of the spacer 2b only from the central portion toward the outer side in the extension direction; and a second scraper tooth 4sb provided at two outer edge portions in the width direction of the plurality of spoke portions 2bo at an outer peripheral end in the extension direction.

Description

Cutter disc of a shield excavator and a shield excavator equipped with the cutter disc

The present invention relates to the technology of a cutter disc of a shield excavator and a shield excavator equipped with the cutter disc.

The shield excavator is a machine that forms an excavation pit on the ground while rotating a cutter head provided on the front surface of the machine body while abutting against the excavation surface of the ground while advancing.

The submersible shield excavator series includes soil pressure submersible shield excavator and mud water submersible shield excavator. The structure of the former shield excavator is to inject additives into the cabin to make the excavated soil and sand muddy (fluidized) and give a predetermined pressure, thereby stabilizing the excavation surface. More specifically, this type of shield machine fills the excavation soil and sand between the excavation surface and the partition wall, and injects and stirs the additives in it, so that the soil and sand become soil (a mixture of gravel and additives) with high fluidity and high water-tightness. Here, the soil and sand mixed with the additives in the cabin are drawn in by the screw conveyor and discharged from the rear of the machine body. The structure of the latter shield excavator is to apply a predetermined pressure to the muddy water in the cabin, thereby stabilizing the excavation surface and circulating the muddy water, and transporting the excavated soil and sand in a fluid state.

Here, the cutter disc system of the earth pressure submersible shield excavator includes: a hub portion located at the center of rotation; a plurality of spoke portions extending radially from the hub portion; and an outer peripheral ring portion connecting a plurality of The outer peripheral end in the extending direction of the spoke portion. Furthermore, through-holes are formed between the spokes, and the through-holes are used to take in earth and sand excavated by the cutter head into the cabin formed on the back of the cutter head.

Each spoke part is equipped with various excavating means such as a rotary chisel, a pilot bit, and scraper teeth. The rotary chisel is arranged in front of each spoke part, and is mainly used to crush pebbles, boulders, etc. (hereinafter also referred to simply as "pebbles"). A plurality of pilot bits are arranged in front of each spoke portion to perform pilot excavation and protect scraper teeth. Furthermore, the scraper teeth are arranged on the two outer edges in the width direction of each spoke portion, that is, the outer peripheral corners of the inlet for digging soil and sand, and a plurality of them are arranged along the extending direction of each spoke portion to excavate the ground and take the excavated soil and sand into the cabin (for example, refer to Patent Documents 1 to 5).

[Prior Art Literature]

[Patent Document]

Patent Document 1: Japanese Patent Laid-Open No. 2012-122257

Patent Document 2: Japanese Patent Laid-Open No. 2012-122258

Patent Document 3: Japanese Patent Laid-Open No. 2012-122259

Patent Document 4: Japanese Patent Laid-Open No. 2012-122260

Patent Document 5: Japanese Patent Application Laid-Open No. 10-140984

In addition, in the earth pressure submersible shield excavator, when there are pebbles having a maximum diameter larger than the maximum diameter that can be taken in from the through-hole formed in the cutter head, the pebbles are crushed by the drill bit and then taken in. If pebbles that cannot be carried by the screw conveyor are taken in, because the pebbles cannot be crushed in the cabin, they will not be crushed in the cabin. It is broken and stirred until the wear becomes the diameter of the gravel that can be transported by the screw conveyor, thus causing damage to the stirring rod, torque arm, etc. Therefore, the maximum diameter of the pebbles taken from the cutter disk must be below the diameter of the pebbles that can be transported by the screw conveyor.

When excavating a conglomerate layer with extremely high gravel content and boulders with a soil pressure submersible shield excavator, when a large-diameter pebble is located on the inner peripheral side of the cutter head (inside from the central part in the extending direction of the spoke part), the pebble rolls and moves toward the outer peripheral side of the spoke part (outside from the central part in the extending direction of the spoke part) of the through hole having a size that can take in the pebble after leaving the excavation site. In addition, until the pebbles enter the through-holes on the outer peripheral side, they hit the spokes and the drills attached to the spokes many times, causing wear and damage to the drills, the spokes, and the like.

Furthermore, this tendency is more prominent in smaller shield excavators with a shield diameter of about 2000 mm to about 4500 mm than larger shield excavators with a shield diameter of 6000 mm or more.

Here, if the scraper teeth protruding from the side surface of the spoke portion are arranged only on both outer edge portions in the width direction of the outer peripheral side of the spoke portion and not on the inner peripheral side, the maximum diameter of pebbles that can be taken into the through hole formed on the inner peripheral side can be increased, thereby suppressing the wear and damage of the above-mentioned drill bit and the spoke portion.

However, the excavation capability of the ground may be lowered on the inner peripheral side of the spoke portion where the scraper teeth are not arranged.

The present invention was made in view of the above-mentioned technical background, and an object of the present invention is to provide a technology that does not lower the digging ability of the ground on the inner peripheral side of the spoke portion where the scraper teeth are not disposed on the cutter head of the shield excavator.

In order to solve the above-mentioned problems, the cutter disc system of the shield excavator according to the first aspect of the present invention has: a hub part, which is located at the center of rotation; a plurality of spoke parts, which extend radially from the hub part; The through hole is formed between the plurality of spokes for taking in excavated soil and sand; the outer peripheral ring is connected to the outer peripheral ends of the plurality of spokes in the extending direction; the plurality of leading drills are arranged in front of the plurality of spokes; the inclined surface is formed only on the inside from the central part of the extending direction of the plurality of spokes, and constitutes both sides of the width direction of the spokes, and the two sides face from the front to the rear of the spokes The directions approaching each other are inclined; the first scraper teeth are provided only on the two outer edges in the width direction outside the central portion in the extending direction of the plurality of spoke portions; and the second scraper teeth are arranged on both outer edge portions in the width direction of the outer peripheral ends in the extending direction of the plurality of spoke portions; among the plurality of spoke portions, the distance in the extending direction of the spoke portion of the leading drill bit arranged on the inner side from the central portion is smaller than that of the leading drill bit arranged on the outer side of the central portion. The pitch in the extending direction of the aforementioned spoke portions.

In the second aspect of the present invention, the cutter disc of the shield excavator is the invention of the first aspect, and the aforementioned inclined surface is equipped with a wear-resistant steel plate.

In the third aspect of the present invention, the cutter disk of the shield excavator is the invention of the second aspect, wherein the wear-resistant steel plate is coated to prevent adhesion of excavated soil and sand.

In the fourth aspect of the present invention, the tool disc of the shield excavator is based on the invention of the first aspect, wherein an adhesion preventing plate for preventing adhesion of excavated soil and sand is installed on the inclined surface.

According to the fifth aspect of the present invention, the tool disc of the shield excavator is based on the invention of the first aspect, wherein the inclined surface is coated to prevent adhesion of excavated soil and sand.

According to the sixth aspect of the present invention, the cutter head of the shield excavator is any one of the first to fifth aspects, and further has a protective member. The protective member is only provided on the inner side from the central part in the extending direction of the plurality of spoke parts, so as to protect the inner side from the central part in the extending direction of the aforementioned spoke parts.

In the seventh aspect of the present invention, the cutter head of the shield excavator is the invention of the sixth aspect, wherein the protective member is at least one of wear-resistant steel plates disposed on both outer edges of the spoke portion in the width direction and wear-resistant steel plates disposed on the front surface of the spoke portion.

In the sixth or seventh aspect of the present invention, the shield excavator cutter head of the eighth aspect of the present invention is the above-mentioned protection member is a surfacing part, and the surfacing part is formed on the entire side of the front panel of the spoke part in the width direction inside from the central part in the extending direction of the above-mentioned spoke part.

A shield excavator according to a ninth aspect of the present invention is the cutter head of any one of the first to eighth aspects in which the front of the machine body is freely rotatable.

According to the present invention, only the both side surfaces in the width direction on the inner peripheral side of each spoke portion are inclined surfaces that incline toward each other from the front to the rear of the spoke portion. Thereby, the excavation surface excavated by the front pilot bit on the inner peripheral side will be scraped and excavated by the spoke portion on the inner peripheral side, and then taken into the machine.

Therefore, the excavation capability of the ground will not be lowered even on the inner peripheral side of the spoke portion where the scraper teeth are not arranged.

1: Earth pressure submersible shield excavator (submersible shield excavator)

2: Tool head (cutter disc)

2a: hub part

2b: spoke part

2ba: front panel

2c: Middle ring part

2d: Outer peripheral ring

2e: Through hole

3: Machine body

3a: Front housing plate

3b: rear shell plate

4a: Center drill bit (drill bit)

4b: Leading drill bit (drill bit)

4c: peripheral drill bit (drill bit)

4d: Profiling drill

4s: scraper teeth

4sa: the first scraper tooth

4sb: Second scraper tooth

4t: wear-resistant steel plate (protective member)

4v: mounting plate

4w: Overlay welding part (protective component)

5a: Additive material injection port

5b: Additive material injection part

6: Cabin

7: Partition wall

8: Tool drive body

9a: Middle fold jack

9b: Shield Jack

10:Screw conveyor

10a: Soil and sand intake end

10b: Discharge end

10c: paddle

15,16: stirring wing

SG: Segment Component

TS: sloped surface

X, Y: Arrow

Z: part

Fig. 1 is a perspective view showing the internal structure of an earth pressure submersible shield excavator according to an embodiment of the present invention from a side perspective.

Fig. 2 is a front view of the cutter head of the earth pressure submersible shield excavator shown in Fig. 1 .

Fig. 3 is a side view of the tool head viewed from the direction of arrow A1 in Fig. 2 .

Fig. 4 is a sectional view when viewed according to the arrow X in Fig. 2 .

Fig. 5 is a cross-sectional view enlargedly showing the Z portion in Fig. 4 .

Fig. 6 is a cross-sectional view when viewed according to the arrow Y in Fig. 2 .

An example of an embodiment of the present invention will be described in detail below with reference to the drawings. Here, in the drawings for explaining the embodiments, the same components are in principle given the same symbols and redundant descriptions are omitted.

1 is a perspective view showing the internal structure of the earth pressure submersible shield excavator of this embodiment from the side. FIG. 2 is a front view of the cutter head of the earth pressure submersible shield excavator in FIG. 1. FIG. 3 is a side view when viewing the cutter head in the direction of arrow A1 in FIG.

The machine of this embodiment is an earth pressure submersible shield excavator (submersible shield excavator) 1, which injects and stirs additives into the soil sand excavated by the cutter head (cutter disc) 2 to produce soil with impermeability and plastic fluidity (free deformation and movement properties), and digs under the state filled with the soil in the cabin between the cutter head 2 and the machine body 3 to generate earth pressure, and builds an excavation pit with the earth pressure against the soil pressure on the excavation surface.

The soil pressure submersible shield excavator 1 is particularly suitable for excavating a site containing a pebble-mixed gravel layer, a pebble layer, etc. mixed with boulders, but it can also be used for a pebble-mixed gravel layer, a pebble layer, or a normal gravel layer that is not mixed with boulders.

Here, the excavation outer diameter of the earth pressure submersible shield shovel 1 is, for example, about 4500 mm. In addition, the captain length of the soil pressure submersible shield excavator 1 is, for example, about 6400 mm. In addition, the operation of the earth pressure submersible shield excavator 1 is controlled by an operator in an operation room in a subsequent vehicle (not shown) arranged behind it.

The cutter head 2 is a component for excavating the excavation surface of the ground, and it is installed on the front of the machine body 3 in a state where it can rotate freely along the circumferential direction of the machine body 3 . The tool head 2 is, for example, in the form of a disc-shaped spoke. That is, as shown in FIG. 2, the tool head 2 is equipped with: a hub portion 2a located at the center of rotation; The six spoke parts 2b extend radially from the hub part 2a toward the outer periphery; the middle ring part 2c connects the midway parts in the extending direction of each spoke part 2b; the outer peripheral ring part 2d connects the front ends of each spoke part 2b;

The hub portion 2a of the cutter head 2 is provided with a center drill (drill) 4a. In addition, other excavating means such as a cone-shaped rotary chisel may be installed on the hub portion 2a.

As shown in the figure, the dimension of each spoke portion 2b in the width direction (rotation direction of the cutter head 2) is formed to be narrower as it approaches the hub portion 2a on the inner side (hereinafter referred to as “inner peripheral side”) from the central portion in the extending direction of the spoke portion 2b (herein referred to as a portion slightly shifted from the mounting position of the intermediate ring portion 2c to the hub portion 2a), and the outer side (hereinafter referred to as “outer peripheral side”) from the central portion in the extending direction of the spoke portion 2b is formed to have the same dimension in the width direction.

Since the inner peripheral side of the spoke part 2b is formed such that the spoke part 2b gradually becomes wider from the hub part 2a, the opening area of the through hole 2e can be ensured as much as possible and the strength stability of the spoke part 2b can be achieved at the same time. In other words, if the dimension in the width direction of the inner peripheral side of the spoke portion 2b is narrowed, the opening area of the through hole 2e can be widened, but the strength will decrease. Conversely, if the dimension in the width direction of the inner peripheral side of the spoke portion 2b is increased, the strength will increase, but the opening area of the through hole 2e will decrease.

In addition, since the outer peripheral sides of the spoke portions 2b are formed to have the same dimension in the width direction, the opening area of the through hole 2e can be increased, in other words, the opening ratio can be increased.

Here, in this embodiment, the central portion in the extending direction of the spoke portion 2b refers to a portion slightly closer to the hub portion 2a than the mounting position of the intermediate ring portion 2c, but it may also be the same position as the mounting position of the intermediate ring portion 2c, or a portion closer to the outer peripheral ring portion 2d than the mounting position of the intermediate ring portion 2c. Furthermore, the central portion in the extending direction of the spoke portion 2b does not need to be exactly half of the total length of the spoke portion 2b, but may be approximately half of the total length of the spoke portion 2b.

In addition, in this embodiment, the inner peripheral side of the spoke portion 2b is formed so that the dimension in the width direction becomes narrower as it approaches the hub portion 2a, and the outer side from the central portion is formed so that the dimension in the width direction is the same. However, the entire length of the spoke portion 2b may be formed to have the same width, or the entire length of the spoke portion 2b may be formed so as to become narrower as it approaches the hub portion 2a.

Each spoke portion 2b is provided with a pilot drill (drill) 4b, scraper teeth 4s, and wear-resistant steel plate (protective member) 4t. In this embodiment, the height of the pilot bit 4b (from the surface of the spoke portion 2b) is 150mm, the height of the scraper teeth 4s is 100mm, and the protrusion (the protrusion from the side of the spoke portion 2b) is 100mm. In addition, in addition to the pilot bit 4b, other excavating means such as a rotary chisel may be installed on the side surface of the spoke portion 2b.

In addition to crushing pebbles and excavating the ground, the leading drill bit 4b also has the function of protecting the scraper teeth 4s. As shown in FIG. Each pilot bit 4b is formed in a planar shape, for example, in a substantially rectangular shape, and is arranged with its long side along the width direction of the spoke portion 2b.

In addition, in this embodiment, the position of the cutter head 2 adjacent to the leading drill bit 4b in the rotation direction is arranged on a different rotation trajectory, but it is not limited thereto, and may be arranged on the same rotation trajectory.

The scraper teeth 4s excavate the ground and take the excavated soil and sand into the cabin body 6 ( FIG. 1 ), which includes the first scraper teeth 4sa and the second scraper teeth 4sb. The first scraper teeth 4sa are provided only on both outer edge portions in the width direction on the outer peripheral side of each spoke portion 2b. The second scraper teeth 4sb are provided on both outer edge portions in the width direction of the outer peripheral end portions in the extending direction of each spoke portion 2b. In addition, as described later, the mounting position of the first scraper teeth 4sa varies depending on the spoke portion 2b, but in the present invention, the radially outer side from the first scraper teeth 4sa installed closest to the hub portion 2a (in FIG.

In this embodiment, the installation positions of the first scraper teeth 4sa of adjacent spoke portions 2b are offset from each other along the radial direction of the cutter head 2 . Specifically, in FIG. 2 , the first scraper teeth 4sa disposed at the positions corresponding to the twelve o'clock direction and the six o'clock direction of the dial surface of the clock, the first scraper teeth 4sa disposed at the positions corresponding to the two o'clock direction and the eight o'clock direction of the clock dial surface, and the first scraper teeth 4sa disposed at the positions corresponding to the four o'clock direction and the ten o'clock direction of the clock dial surface are arranged to be staggered from each other, so that the trajectories of all the first scraper teeth 4sa when the tool head 2 rotates are different, and no ground will occur. Excavate the remaining area.

In addition, two kinds of second scraper teeth 4sb with different lengths are provided in this embodiment. In FIG. 2 , the second scraper teeth 4sb arranged at positions corresponding to the two o'clock direction and the eight o'clock direction of the dial surface of the clock are longer than the second scraper teeth 4sb arranged at other positions, and their trajectory when the cutter head 2 rotates slightly overlaps with the first scraper teeth 4sa arranged on the outer peripheral sides of the positions corresponding to the four o'clock direction and the ten o'clock direction of the dial surface of the clock.

With such an arrangement of the first scraper teeth 4sa and the second scraper teeth 4sb, the ground located on the outer peripheral side of the cutter head 2 can be excavated without omission.

As shown in FIG. 4 and FIG. 6 , only the both side surfaces in the width direction on the inner peripheral side of each spoke portion 2b are sloped surfaces TS inclined toward each other from the front to the rear of the spoke portion 2b. As shown in the figure, in this embodiment, the inclination angle of the inclined surface TS (the angle formed by the line perpendicular to the front panel 2ba of the spoke portion 2b and the inclined surface TS) is 5°. This inclined surface TS has the same function as the above-mentioned scraper teeth 4s on the outer peripheral side, scraping and excavating the excavation surface excavated by the leading bit 4b into the cabin body 6 . Here, the inclination angle of the inclined surface TS is not limited to 5° and can be freely set.

Here, as shown in FIG. 4 and FIG. 6 , the inclined surface TS is provided with a wear-resistant steel plate 4t for protecting the inclined surface TS to prevent wear and damage of the spoke portion 2b caused by ground excavation. Additionally, for The wear-resistant steel plate 4t attached to the inclined surface TS can be coated with an anti-sand adhesion agent such as powder or liquid. Such coating treatment for preventing adhesion of excavated soil and sand can eliminate deterioration of excavation efficiency caused by a reduction in excavation amount of soil and sand on the excavated surface due to soil and sand adhering to the inclined surface TS.

In addition, instead of the wear-resistant steel plate 4t, an adhesion prevention plate for preventing adhesion of excavated earth and sand may be attached to the inclined surface TS. Alternatively, the coating treatment for preventing adhesion of excavated earth and sand may be directly applied to the inclined surface TS without attaching the wear-resistant steel plate 4t, the adhesion preventing plate, and the like. Here, even if the anti-adhesion plate is installed on the inclined surface TS or the anti-adhesion coating treatment is applied to it, as mentioned above, it is possible to eliminate the deterioration of the excavation efficiency caused by the reduction of the excavation amount of earth and sand on the excavation surface due to the adhesion of earth and sand to the inclined surface TS.

Furthermore, in this embodiment, as shown in FIGS. 2 , 4 and 5 , a wear-resistant steel plate 4t is installed via a mounting plate 4v on both outer edges in the width direction of the inner peripheral side of each spoke portion 2b and the front surface of the inner peripheral side of each spoke portion 2b (specifically, the surface of the front panel 2ba of the spoke portion 2b). By providing the wear-resistant steel plate 4t, both outer edges and the surface in the width direction on the inner peripheral side of each spoke portion 2b can be protected, and wear and damage of the spoke portion 2b caused by excavation of the ground can be prevented.

In addition, in this embodiment, wear-resistant steel plates 4t are installed on the two outer edges in the width direction and the front surface of the inner peripheral side of each spoke portion 2b, but the wear-resistant steel plates 4t can also be installed on any of the two outer edges in the width direction or the front surface. In addition, the wear-resistant steel plate 4t can also be directly mounted on the spoke portion 2b without interposing the mounting plate 4v.

Furthermore, as shown in FIGS. 4 to 6 , the inner peripheral side of each spoke portion 2b is formed with a surfacing portion (protective member) 4w on the entire width direction side surface of the front panel 2ba of the spoke portion 2b. Thereby, the abrasion resistance of the inner peripheral side of the spoke part 2b at the time of ground excavation can be improved.

Here, the maximum diameter of the pebbles taken in through the through hole 2e depends on the size (diameter) of the screw conveyor 10, but in the earth pressure submersible shield excavator 1 of this embodiment, the diameter of the screw conveyor 10 is The pebbles with a diameter of about 700mm x 600mm can be transported, so the through hole 2e formed in the cutter head 2 is suitable for the size of the pebbles with a maximum diameter of 700mm.

If pebbles of a size that cannot be transported by the screw conveyor 10 are taken into the through hole 2e, since the pebbles cannot be crushed in the cabin body 6, they will be continuously stirred in the cabin body 6 until they are worn away and become a gravel diameter that can be transported by the screw conveyor 10.

The hub part 2a and the spoke part 2b are provided with an additive injection port 5a. The additive material injection port 5 a is a component for injecting a clay material such as a bentonite-based additive material toward the excavation surface on the front side of the cutter head 2 . Here, as the additive injected from each additive injection port 5a, a foam material may be used instead of the bentonite-based additive, or both of the benthite-based additive and the foam material may be used.

The earth and sand excavated by the cutter head 2 are taken into the cabin body 6 (referring to FIG. 1 ) described later through the through-hole 2e, but when the opening area of the through-hole 2e is limited by the intermediate ring portion 2c connecting the middle part of the extension direction of each spoke portion 2b, the size of the pebbles taken in through the through-hole 2e can be limited. Here, when the excavation outer diameter of the earth pressure submersible shield excavator 1 is small (for example, 2000mm), the intermediate ring portion 2c can be omitted.

A plurality of outer peripheral drill bits (drill bits) 4c are arranged in series on the front face of the outer peripheral ring portion 2d facing the excavation face. In addition, the height of the peripheral drill 4c is also formed to be 150 mm. In addition, the height of the peripheral drill bit 4c adjacent to the cutter head 2 in the rotation direction can be set to be different along the rotation direction of the cutter head 2 by repeated ups and downs. In this way, the impact and load received by the outer peripheral drill 4c can be dispersed to improve the durability of the outer peripheral drill 4c, and the replacement time of the outer peripheral drill 4c of the cutter head 2 can be extended. In addition, by changing the height of the outer peripheral bit 4c on the same rotation trajectory, pebbles and the like on the excavation surface can be finely chopped.

In addition, on the outer peripheral surface of the outer peripheral ring portion 2d, for example, two copy cutters (copy cutter) 4d are provided at opposite pole positions. The profiling drill bit 4d is used for over-excavation during construction of sharply curved lines, posture control of the soil pressure submersible shield excavator 1, and the like.

Moreover, as shown in FIG. 1 , the machine body 3 is provided with a front casing panel 3 a of a truss portion and a rear casing panel 3 b of a rear rear portion. The front case plate 3 a and the rear case plate 3 b are members formed of, for example, cylindrical steel plates, which form the outer shape of the machine body 3 and form a hollow space inside the machine body 3 . The front housing plate 3a and the rear housing plate 3b are coupled to each other by being fitted into the rear end side of the front housing plate 3a while the spherical bearing portion at the front end of the rear housing plate 3b is in contact with the inner peripheral surface of the front housing plate 3a.

On the front side of the front casing plate 3a, a partition wall 7 is provided at a position where the front face recedes toward the inside of the machine body 3, and the partition wall 7 divides the hollow space in the machine body 3 into the excavation surface side and the inside of the machine. On the side of the excavation surface of the partition wall 7 (that is, between the cutter head 2 and the partition wall 7), a cabin body 6 is provided. On the inside of the partition wall 7, an additive material injection part 5b, a cutter driving body 8, a middle folding jack (jack) 9a, a shield jack 9b, a screw conveyor 10, and an earth pressure detection part (not shown) are provided.

The additive material injection part 5b is a machine for injecting additive materials toward the periphery of the machine body 3 and the cabin body 6, and is provided near the outer periphery of the partition wall 7 so that the injection port of the additive material injection part 5b is exposed to the outside of the machine body 3. The additives injected from the additive injection part 5b are clay materials such as bentonite-based additives. Here, as the additive injected from the additive injection part 5b, a foam material may be used instead of the bentonite-based additive, or both of the benthite-based additive and the foam material may be used.

The cabin body 6 is a space for taking in the earth and sand excavated by the cutter head 2 . In the cabin body 6, the front side of the partition wall 7 is provided with a cylindrical stirring blade 15 protruding in the cabin body 6; The configuration of the 15 and 16 series of stirring wings The radial positions of the cutter head 2 are staggered from each other, and when the cutter head 2 rotates, the earth and sand entering the cabin body 6 are stirred and mixed with the additives injected into the cabin body 6 .

The tool driving body 8 is a driving source for rotating the tool head 2 . Here, the tool driving method is an example of an intermediate support driving method. As shown in FIG.

The folding jack 9a is a machine that connects the front casing plate 3a and the rear casing plate 3b and corrects the propulsion direction of the earth pressure shield excavator 1. As shown in FIG. By supplying hydraulic pressure to the folding jack 9a, the front casing plate 3a and the rear casing plate 3b are bent into a predetermined direction and angle, and the earth pressure shield excavator 1 is propelled to control the propulsion direction of the earth pressure shield excavator 1.

The shield jack 9b exerts a force on the segment member SG arranged behind the machine body 3, and generates propulsive force for the soil pressure shield excavator 1 to advance through its reaction force. As shown in FIG.

The screw conveyor 10 is a machine used to discharge the earth and sand taken into the cabin body 6 out of the machine. As shown in FIG.

As the screw conveyor 10 , for example, a shaftless spiral belt type screw conveyor is used. The shaftless spiral belt type screw conveyor is equipped with a helical paddle 10c without a rotating shaft in a pipe. A screw conveyor with a rotating shaft is likely to be blocked by pebbles. In contrast, if it is a screw conveyor with a shaftless spiral belt 10, the maximum diameter of the pebbles that can be transported is more than the radius of the transport path, and pebbles of a size that cannot be transported by the shaft screw conveyor can be transported. Thereby, the earth pressure submersible shield excavator 1 of the present embodiment is configured to be able to take pebbles and the like of a size that can be discharged by the screw conveyor 10 into the cabin 6 without crushing them.

A soil discharge pipe (not shown) is connected to the discharge end 10b of the screw conveyor 10, and the soil and sand conveyed to the discharge end 10b of the screw conveyor 10 can be conveyed to a trolley or the like through the discharge pipe.

The soil pressure detection part is a sensor part that converts the pressure caused by the soil in the cabin body 6 into an electrical signal through the strain gauge, and is set so that the soil pressure detection surface of the soil pressure detection part faces the inside of the cabin body 6 . The soil pressure submersible shield excavator 1 manages the soil pressure in the cabin 6 detected by the soil pressure detection unit within a predetermined value range, thereby enabling excavation while maintaining the stability of the excavation surface.

Next, the earth pressure shield construction method performed by the earth pressure shield excavator 1 shown in FIG. 1 will be described. Here, the excavation target is the site composed of conglomerate layers with extremely high gravel content and containing boulders.

When excavating such a ground, the earth pressure submersible shield excavator 1 of this embodiment rotates the cutter head 2 in a state pressed against the excavation surface and simultaneously pushes the machine body 3 to construct an excavation pit in the ground.

When carrying out this excavation operation, additives are added to the soil and sand excavated by the cutter head 2, and the soil, sand and additives are mixed by the rotation of the cutter head 2 and the action of the stirring blade 16 following the rotation, so as to convert the excavated soil and sand into soil with plastic fluidity and impermeability. Then, make its soil be filled in the cabin body 6 and in the screw conveyor 10, and pressurize the filled soil by the propulsive force of the shield jack 9b to generate soil pressure, so that the soil pressure resists the soil pressure of the excavation surface and maintains the stability of the excavation surface. In addition, for example, when the rotation speed of the cutter head 2 is constant, the extension speed of the shield jack 9b, The rotation speed of the screw conveyor 10 and the like are also measured by the above-mentioned soil pressure detector to make the soil pressure in the cabin body 6 constant, thereby maintaining the stability of the excavated surface.

The bentonite-based additives (as clay materials) added as additives have the effect of improving the plastic fluidity and water impermeability of the soil and sand, and have the function of enveloping the gravel, pebbles and other stone components obtained by crushing boulders together with the excavated soil and sand so that the stone components will not be separated from the excavated soil and sand, and the integration of the excavated soil, sand and stone components will be improved.

Here, if the maximum diameter of the pebbles that can be taken in the through holes 2e on the outer peripheral side of the cutter head 2 is greater than the maximum diameter of the pebbles that can be taken in by the through holes 2e on the inner peripheral side of the cutter head 2, the pebbles that have not entered the through holes 2e on the inner peripheral side move to the outer peripheral side of the spoke portion 2b and enter the through holes 2e on the outer peripheral side. During its movement, pebbles collide with the spoke portion 2b and the leading drill bit 4b mounted on the spoke portion 2b for many times, thereby impelling the wear and tear of the leading drill bit 4b and the spoke portion 2b.

On the other hand, in the earth pressure submersible shield excavator 1 of this embodiment, as mentioned above, the scraper teeth 4s protruding from the side surfaces of the spokes 2b are not installed on the inner peripheral side of each spoke portion 2b, so the maximum diameter of the pebbles that can be taken in through the through hole 2e does not differ between the inner peripheral side and the outer peripheral side of the cutter head 2. Therefore, when the large-diameter pebble that the through hole 2e can take in is located on the inner peripheral side of the cutter head 2, the pebble will be directly taken in from the inner peripheral through hole 2e and sent into the cabin body 6 after breaking away from the excavated ground.

At this time, only the both side surfaces in the width direction on the inner peripheral side of each spoke part 2b are inclined surfaces TS inclined toward the directions approaching each other from the front to the rear of the spoke part 2b. Thereby, the inclined surface TS has the same function as the scraper teeth 4s on the outer peripheral side, and the site of the trenched excavation surface by the front pilot bit 4b on the inner peripheral side will be scooped and excavated by the spoke portion 2b on the inner peripheral side and taken into the cabin body 6 (that is, in the machine).

Therefore, even on the inner peripheral side of the spoke portion 2b where the scraper teeth 4s are not arranged, the excavation capability of the ground will not be lowered.

The invention developed by the present inventors has been specifically described above based on the embodiments, but each point of the embodiments disclosed in this specification is an illustration, and it should be understood that it is not limited to the disclosed technology. That is to say, the technical scope of the present invention should not be construed restrictively based on the descriptions in the above-mentioned embodiments, but should be interpreted according to the description of the scope of patent application, which includes the technology equivalent to the technology described in the scope of patent application and all changes that do not depart from the gist of the scope of patent application.

For example, in the aforementioned embodiment, the case of using a shaftless spiral belt type screw conveyor has been described, but it is not limited to this and various changes can be made. For example, a combination of a shaftless spiral belt type and a shaft type screw conveyor can also be used.

[industrial availability]

In the above description, the case where the present invention is applied to the earth pressure shield excavator of the intermediate support drive method has been described, but it is not limited to this, and it can also be applied to other shield excavators such as the earth pressure shield excavator of the spindle drive method and the peripheral support drive method.

2b: spoke part

2ba: front panel

4t: wear-resistant steel plate (protective member)

4v: mounting plate

4w: Overlay welding part (protective component)

TS: sloped surface

Z: part

Claims (6)

A cutter disc of a shield excavator has: a hub portion located at the center of rotation; a plurality of spokes extending radially from the hub; through holes formed between the plurality of spokes for taking in excavated soil and sand; an outer ring portion connecting the outer peripheral ends of the extending direction of the plurality of spokes; a plurality of leading drill bits arranged in front of the plurality of spokes; an inclined surface formed only in the plurality of spokes The inner side of the distance from the center of the distance between the center of rotation when viewed from the front of the cutter head and the outer end of the spoke portion in the extending direction of the blade portion constitutes both sides in the width direction of the spoke portion. The two outer edges in the width direction of the outer peripheral end in the extending direction of the bar portion; among the plurality of spokes, the distance between the spokes of the leading drill located on the inner side from the central part is smaller than the distance in the extending direction of the spokes of the leading drill disposed on the outer side from the central part; The cutter head of the submersible excavator according to claim 1, wherein the included angle between the line perpendicular to the front panel of the spoke portion and the inclined surface is 5°. The cutter head of the shield excavator as described in claim 1 or 2 further has a protective member, and the protective member is only provided on the inner side from the central part in the extending direction of the plurality of spoke parts, so as to protect the inner side from the central part in the extending direction of the spoke parts. The cutter head of a shield excavator according to claim 3, wherein the protective member is a wear-resistant steel plate between the two outer edges in the width direction when viewed from the front of the cutter head and the leading drill bit on the inner side from the central portion in the extending direction of the spoke portion. The cutter head of the submersible excavator according to claim 3, wherein the protective member is a surfacing part formed on the entire side of the front panel in the width direction of the spoke part on the inner side from the central part in the extending direction of the spoke part. A shield excavator, which is the cutter head described in any one of Claims 1 to 5 in a state where the front of the machine body is freely rotatable.

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