TWI809788B - 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 a maximum diameter of pebbles that can be taken from the through hole does not differ between an inner peripheral side and an outer peripheral side. A cutter board of shield excavator of the present invention includes: a hub portion 2a located at the center of rotation; a plurality of spoke portions 2b extending radially from the 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; a wear-resistant steel plate 4t which is provided only from the center portion of the plurality of spoke portions 2b in an extension direction toward the inner side to protect the inner side of the central portion of the spoke portions 2bi n the extending direction; 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.

A shield excavator is a machine that forms an excavation pit on the ground while rotating a cutter wheel 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 additive materials 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 excavator It is to make the excavated soil and sand fill between the excavation surface and the partition wall, and inject and stir the additive materials in it, so that the soil and sand can become highly fluid and water-tight soil (a mixture of gravel and additive materials). Its soil pressure seeks the stability of the excavation surface while excavating. 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 the plurality of spoke portions. The outer peripheral end in the direction of extension. 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, scraper teeth are arranged on both outer edges in the width direction of each spoke portion, that is, at the outer peripheral corners of the inlet for excavating earth and sand, and a plurality of them are arranged along the extending direction of each spoke portion, excavating the ground and excavating the excavated soil. Earth and sand are taken into the cabin body (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 transported by the screw conveyor are taken in, because the pebbles cannot be crushed in the cabin, they will be continuously stirred in the cabin until they are worn out and become the diameter of the gravel that can be transported by the screw conveyor. Moment arm and other damage. 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.

Here, when excavating a conglomerate layer containing boulders with a very high gravel content rate with a soil pressure submersible shield excavator, the large-diameter pebbles are located on the inner peripheral side of the cutter head (inside from the center in the direction in which the spokes extend). In the ground, the pebbles roll and move toward the outer peripheral side of the spoke portion (the outer side from the central portion in the extending direction of the spoke portion) 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.

The present invention was made in view of the above-mentioned technical background, and an object of the present invention is to provide technology in which the maximum diameter of pebbles that can be taken in by the through hole of the cutter head of the shield excavator does not differ from the inner peripheral side and the outer peripheral side.

In order to solve the above-mentioned problems, the tool disc system of the shield excavator of 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 from the aforementioned hub part It is radial; the through hole is formed between a plurality of the aforementioned spoke parts to take in the excavated soil and sand; the outer peripheral ring part is connected to the outer peripheral end of the extending direction of the plurality of the aforementioned spoke parts; the plurality of leading drill bits are It is arranged in front of a plurality of the aforementioned spoke parts; the protective member is only provided on the inner side from the central part of the extending direction of the plurality of aforementioned spoke parts, so as to protect the inner side from the central part of the extending direction of the aforementioned spoke parts; the first scraper The teeth are provided only on the two outer edges in the width direction outside the central part in the extending direction of the plurality of spoke parts; and the second scraper teeth are provided on the outer peripheral ends of the extending direction of the plurality of spoke parts The two outer edge portions in the width direction; among the plurality of spoke portions, the distance between the spoke portions of the aforementioned leading drill bit disposed on the inner side from the central portion is smaller than that of the aforementioned leading drill bits disposed on the outer side from the central portion. The pitch in the extending direction of the aforementioned spoke portions of the drill.

In the invention of the first aspect of the cutter disk system for a shield excavator according to the second aspect of the present invention, among the plurality of spoke portions, the inner side from the central portion in the extending direction is formed so that the dimension in the width direction increases as the spoke portion approaches the hub portion. and become narrower, and the outer sides from the central portion in the extending direction are formed to have the same dimension in the width direction.

In the third aspect of the present invention, in the invention of the first or second aspect of the cutter disc of the shield excavator, the aforementioned protective member is provided between the two outer edges in the width direction of the aforementioned spoke portion and the front of the aforementioned spoke portion. At least any one of wear-resistant steel plates.

In the invention of any one of the first to third aspects, the cutter disc of the shield excavator according to the fourth aspect of the present invention further has an intermediate ring portion, and the intermediate ring portion is provided on the plurality of spoke portions. A plurality of the spoke portions are connected between the hub portion and the outer peripheral ring portion.

The shield excavator according to the fifth aspect of the present invention is the cutter head of any one of the first to fourth aspects in which the front of the machine body is freely rotatable.

According to the present invention, instead of installing the scraper teeth protruding from the side surfaces of the spokes, a protective member is installed inside from the central portion in the extending direction of each spoke. Therefore, the maximum diameter of the pebbles that can be taken in through the through hole does not differ between the inner peripheral side and the outer peripheral side of the cutter head.

In this way, when the large-diameter pebbles that can be taken in from the through hole are located on the inner peripheral side of the cutter head, the pebbles will directly enter the inner through hole after leaving the excavation site, so it is difficult to produce drill bits and spokes. Wear and tear of parts, etc.

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

2: Tool head (cutter disc)

2a: hub part

2b: spoke part

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)

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

A1: Arrow

SG: Segment Component

R: round

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 .

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.

Fig. 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 of Fig. 1, and Fig. 3 is based on Fig. 2 Side view of the tool head when viewed from the direction of arrow A1.

The machine of this embodiment is a soil pressure submersible shield excavator (submersible shield excavator) 1, which injects and stirs additive materials into the soil and sand excavated by the cutter head (cutter disc) 2 to produce impermeable and plastic materials. Fluid (freely deformable and mobile) soil, and excavation is carried out in a state where the soil is filled in the cabin between the cutter head 2 and the machine body 3 to generate soil pressure, and the soil pressure is used against the excavation surface Construct the excavation pit according to the state of soil pressure.

This soil pressure submersible shield excavator 1 is especially 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 ordinary gravel without boulders. layers etc.

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 Figure 2, the tool head 2 is equipped with: a hub portion 2a, which is located at the center of rotation; six spoke portions 2b, which extend radially from the hub portion 2a toward the outer periphery; The middle part of the extending direction of the spoke part 2b; the outer peripheral ring part 2d, which connects the front ends of each spoke part 2b; and the through hole 2e, which is formed between each spoke part 2b, for taking excavated soil and sand into the cabin. In body 6.

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 the width direction of each spoke portion 2b (the direction of rotation of the cutter head 2) is at the central portion of the extension direction of the spoke portion 2b (here, it means that the mounting position of the intermediate ring portion 2c is slightly closer to the hub The inner side (hereinafter referred to as "inner peripheral side") from the position of the spoke part 2a) is formed so that it becomes narrower as it approaches the hub part 2a, and the outer side (hereinafter referred to as "inner peripheral side") from the central part in the extending direction of the spoke part 2b is formed. Outer peripheral side"), the dimensions in the width direction are formed to be the same.

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, although the opening area of the through hole 2e can be increased, the strength will decrease. Conversely, if the dimension in the width direction of the inner peripheral side of the spoke portion 2b is As the size increases, the strength will increase, but the opening area of the through hole 2e will be greatly reduced.

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 installation position of the intermediate ring portion 2c, but it may also be the same as the installation position of the intermediate ring portion 2c. position, or a position 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, but it may be 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 taking the lead in crushing pebbles and excavating the ground, the leading bit 4b also has the function of protecting the scraper teeth 4s. As shown in FIG. A plurality of leading drill bits 4b are arranged side by side. 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 installation position of the first scraper tooth 4sa is different according to the spoke portion 2b, but in the present invention, the first scraper tooth 4sa installed closest to the hub portion 2a (in FIG. The radially outer side from the first scraper teeth 4sa) on the spoke portion 2b at positions corresponding to the twelve o'clock direction and the six o'clock direction on the dial surface of the clock is referred to as the outer peripheral side of the spoke portion 2b.

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 provided at positions corresponding to the twelve o'clock direction and the six o'clock direction of the dial surface of the clock, and the first scraper teeth 4sa arranged at the positions corresponding to the two o'clock direction and the eight o'clock direction of the dial surface of the clock. The first scraper tooth 4sa at the position in the clock direction and the first scraper tooth 4sa at the positions corresponding to the four o'clock direction and the ten o'clock direction of the dial surface of the clock are configured to be staggered from each other so that the cutter head 2 rotates The trajectories of all the first scraper teeth 4sa are different so that there is no excavation residual area of the ground.

In addition, in this embodiment, there are two kinds of second scraper teeth 4sb with different lengths. In FIG. The degree is greater than that of the second scraper teeth 4sb provided at other positions, and its trajectory when the tool head 2 rotates is set on the outer peripheral side of the position corresponding to the four o'clock direction and the ten o'clock direction of the dial surface of the clock. The trajectories of the first scraper teeth 4sa slightly overlap.

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.

Furthermore, on the inner peripheral side of each spoke part 2b (specifically, the two outer peripheral parts on the inner peripheral side), both outer edge parts in the width direction and the front surface on the inner peripheral side of each spoke part 2b, a resistance The wear plate 4t is not provided with scraper teeth 4s. By providing this wear-resistant steel plate 4t, both outer edge parts and the surface in the width direction of the inner peripheral side of each spoke part 2b can be protected.

Thereby, since there are no scraper teeth 4s protruding from the side surface of the spoke portion 2b on the inner peripheral side of each spoke portion 2b, the maximum diameter of the pebble that can be taken in through the hole 2e (the circle indicated by the symbol R in FIG. 2 Shape) will not be different on the inner peripheral side and the outer peripheral side of the cutter disc 2.

In addition, in this embodiment, the wear-resistant steel plate 4t is installed on the two outer edges and the front surface of the inner peripheral side of each spoke portion 2b in the width direction, but the wear-resistant steel plate 4t can also be installed on the two outer sides in the width direction. Either edge or front.

Here, the maximum diameter of the pebbles taken in through the through hole 2e will depend 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 can be changed. Pebbles with a gravel diameter of about 700mm×600mm are transported, so the through-hole 2e formed in the cutter head 2 is of a size that can accommodate 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 and can be transported by the screw conveyor 10. At this time, it will cause damage to the stirring blades 15, 16 (described later), so the maximum diameter of the pebbles taken in the cabin body 6 must be below the 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 soil and sand excavated by the cutter head 2 are taken into the cabin body 6 (refer to FIG. 1 ) described later through the through-hole 2e, but the through-hole is limited by the intermediate ring portion 2c connecting the middle part of the extension direction of each spoke portion 2b. When the opening area of 2e is increased, the size of the pebbles taken in by 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 150mm. 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 period 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 fitted into the rear end side of the front housing plate 3a in a state where 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. coupled with each other.

On the front side of the front casing plate 3a, a partition wall 7 is provided at a position where the front face recedes to 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. . The side of the excavation surface of this partition wall 7 (that is, between the cutter head 2 and the partition wall 7) is provided with a cabin body 6, and the inside of the partition wall 7 is provided with an additive material injection part 5b, a cutter driving body 8, a middle fold Jack 9a, shield jack 9b, screw conveyor 10, and earth pressure detection unit (not shown).

The additive material injection part 5b is a machine that injects additive materials toward the periphery of the machine body 3 and the cabin body 6, and is provided on the outer periphery of the partition wall 7 in a state where the injection port of the additive material injection part 5b is exposed to the outside of the machine body 3 nearby. 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. Etc stirring wing 16. These stirring wings 15, 16 are arranged so that the radial positions of the cutter head 2 are staggered from each other, and when the cutter head 2 rotates, the soil sand entering the cabin body 6 and the additive materials injected into the cabin body 6 are stirred and mixed.

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. Configure plural.

The folding jack 9a is a machine that connects the front shell plate 3a and the rear shell plate 3b and corrects the propulsion direction of the earth pressure submersible shield excavator 1, as shown in Figure 1, in the machine body 3, straddling the front shell A plurality of positions of the boundary between the plate 3 a and the rear casing plate 3 b are arranged along the circumferential direction of the earth pressure submersible shield excavator 1 . By supplying oil 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 soil pressure submersion shield excavator 1 is pushed forward to control the soil submersion. Shield excavator 1 propulsion direction.

The shield jack 9b exerts a force on the segmental member SG arranged at the rear of the machine body 3, and generates a propulsive force for the earth to press the shield excavator 1 through its reaction force. As shown in FIG. 1, the shield jack 9b A plurality of them are arranged along the circumferential direction of the earth pressure submersible shield excavator 1 at positions straddling the boundary between the front casing plate 3a and the rear casing plate 3b in the machine body 3 .

The screw conveyor 10 is a machine used to discharge the soil and sand taken into the cabin body 6 out of the machine. As shown in FIG. The intake end 10a is continuously extended toward the discharge end 10b arranged at the rear of the machine body 3 at a position slightly higher than the center of the machine body 3 in the height direction.

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. The screw conveyor with a rotating shaft is likely to be blocked by pebbles. In contrast, if the screw conveyor 10 is a shaftless spiral belt type, the maximum diameter of the pebbles that can be transported is more than the radius of the transport path, and the shaft screw can be transported. Pebbles of a size that cannot be handled by the conveyor. 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 earth pressure submersible shield excavator 1 is used to collect the mud in the cabin body 6 detected by the earth pressure detection department. The soil pressure is managed within a predetermined value range, whereby excavation can be performed 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 a site composed of a conglomerate layer with a very high gravel content and containing boulders.

When excavating such a site, 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 performing this excavation work, additives are added to the soil and sand excavated by the cutter head 2, and the soil, sand and additives are stirred and mixed by the rotation of the cutter head 2, the stirring blade 16 following the rotation, etc., and the The excavated soil and sand are converted 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 soil filled to it by the propulsive force of shield jack 9b and produce soil pressure, with this soil pressure against the soil of excavation face pressure to maintain the stability of the excavation face. 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, etc. are adjusted, and the soil pressure in the cabin body 6 is measured by the above-mentioned soil pressure detection part, so that It becomes constant, thereby maintaining the stability of the excavation surface.

The bentonite-based additive (clay material) added as an additive has the effect of improving the plastic fluidity and impermeability of the soil and sand, and has the function of enveloping gravel, pebbles and other stone components obtained by crushing boulders together with the excavated soil and sand. The function of preventing the stone components from separating from the excavated soil and sand and improving the integrity of the excavated soil, sand and stone components.

Here, if the maximum diameter of the pebble that can be taken in by the through-hole 2e on the outer peripheral side of the cutter head 2 is greater than the maximum diameter of the pebble that can be taken in by the through-hole 2e on the inner peripheral side of the cutter head 2, it will not enter the inner periphery. The pebbles in the side through holes 2e move toward the outer peripheral side of the spoke portion 2b and enter the outer peripheral side through holes 2e. 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 the present embodiment, as mentioned above, the inner peripheral side of each spoke portion 2b is connected to both outer edges in the width direction and the front surface with wear-resistant steel plates 4t. The scraper teeth 4s protruding from the side of the spoke portion 2b are not provided. Thereby, the maximum diameter of the pebbles that can be taken in by the through hole 2e will not be different between the inner peripheral side and the outer peripheral side of the cutter head 2, so the large diameter pebbles that can be taken in by the through hole 2e are located on the inner peripheral side of the cutter head 2. When the site is used, its pebbles will be directly taken in by the through hole 2e on the inner peripheral side after breaking away from the excavated site and sent into the cabin body 6.

Therefore, abrasion and damage of the front pilot bit 4b, the spoke portion 2b, etc. due to pebbles are less likely to occur, and stable operation of the earth pressure submersible shield excavator 1 can be realized.

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 foregoing implementation forms, but should be interpreted according to the description of the scope of patent application, which includes technologies equivalent to those described in the scope of patent application and All changes that do not deviate from the gist of the scope of the patent application.

For example, the case of using a shaftless spiral belt type screw conveyor has been described in the aforementioned embodiments, 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. machine.

[industrial availability]

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

2a: hub part

2b: spoke part

2c: Middle ring part

2d: Outer peripheral ring

2e: Through hole

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)

5a: Additive material injection port

Claims (4)

A cutter disc of a shield excavator comprises: a hub part located at the center of rotation; a plurality of spoke parts extending radially from the hub part; through holes formed between the plurality of spoke parts for To take in the excavated soil and sand; the outer peripheral ring part is connected to the outer peripheral end of the extension direction of the plurality of the aforementioned spoke parts; the plurality of leading drill bits are arranged in front of the plurality of the aforementioned spoke parts; The inner side of the distance from the center of the distance from the center of rotation to the outer end of the spoke in the direction of extension of the spoke portion as viewed from the front of the cutter head to protect the center of the direction of extension of the spoke The first scraper teeth are arranged only on the two outer edges in the width direction outside the central part in the extension direction of the plurality of aforementioned spokes; and the second scraper teeth are arranged on the plurality of aforementioned spokes. The two outer edge portions in the width direction of the outer peripheral end portion in the extending direction of the spoke portion; among the plurality of aforementioned spoke portions, the inner side from the aforementioned central portion in the extending direction is formed so that the dimension in the width direction when viewed from the front of the tool disc follows the It is narrowed near the hub portion, and the outer side from the central portion in the extending direction is formed to have the same dimension in the width direction when viewed from the front of the cutter head; among the plurality of spoke portions, they are arranged on the inner side from the central portion The pitch in the extending direction of the spoke portions of the leading drill bits is smaller than the pitch in the extending direction of the spoke portions of the leading drill bits arranged on the outer side from the central portion. The cutter head of the shield excavator according to claim 1, wherein the protective member is provided on the inner side from the central portion in the extending direction of the spoke portion in the width direction when viewed from the front of the cutter head Between the two outer edges and the aforementioned leading drill bit. The cutter head of a shield excavator according to claim 1 or 2, wherein the protective member is a wear-resistant steel plate. A shield excavator, which is the cutter head according to any one of Claims 1 to 3 in a state where the front of the machine body is freely rotatable.

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