JPH0791176A - Square-shaped cross section shield excavating machine - Google Patents

Abstract

PURPOSE:To excavate a horizontal hole of square cross section. CONSTITUTION:A crank wheel 3 is rotatively supported on a support wall 2 laid out inside a skin plate 1 whose cross section is square-shaped. A rotary bullhead 5 is rotatively supported on a first fixed bulkhead 4 laid out inside the skin plate at a specified spacing in front of the support wall 2. A rotary shaft 15 is rotatively fitted into the center of the crank shaft 3 at a specified deviated position and the center of the rotary bulkhead 5 respectively. An outer gear 31 is fixed with an area between the rotary bulkhead 5 of the rotary shaft 15 and the crank wheel 3, thereby engaging the outer gear 31 with an inner gear 32. A motor 52 is used to drive the crank wheel 3 so that the rotary shaft 15 and a cutter head 20 may make an epicyclic motion, thereby excavating a horizontal hole with the cutter head 20 which is an equilateral triangle in shape.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a square cross section shield excavator for excavating a lateral hole having a substantially square cross section.

[0002]

2. Description of the Related Art Conventionally, as a shield excavator, there is one disclosed in JP-A-63-247497. In this shield excavator, a funnel-shaped hood is fixed to the front end of a cylindrical skin plate, and a partition wall is fixed to the skin plate so as to be located behind the hood, and a space between the rear end of the hood and the partition wall is fixed. The chamber is formed in the. A rotary shaft is rotatably fitted in the center of the partition wall, and a cutter head is fixed to the tip of the rotary shaft. The cutter head is composed of a cone fixed to the tip of the rotary shaft and an excavating portion such as a cutter arm fixed to the tip of the cone, and forms a crushing chamber between the cone and the hood. Then, mud water is supplied to this crushing chamber by a mud pipe, the ground is excavated by the excavation section, the excavated gravel is crushed in the crushing chamber, and the crushed gravel, earth and sand, etc. are guided from the crushing chamber to the chamber, Further, the sludge pipe communicating with the chamber is used to discharge the gas to the outside.

[0003]

By the way, recently, when excavating a lateral hole for a conduit having a square cross section, there is a demand for excavating a lateral hole having a square cross section according to the shape of the conduit. is there.

However, in the conventional shield excavator, the rotary shaft is arranged at the center of the partition wall fixed to the cylindrical skin plate, that is, the center of the cylindrical skin plate, and the cutter head fixed to this rotary shaft is rotated. Since the excavation is performed, the excavated lateral hole is necessarily circular, and there is a problem that the lateral hole having a square cross section cannot be excavated.

Therefore, an object of the present invention is to provide a square section shield excavator capable of excavating a lateral hole having a substantially square section.

[0006]

In order to achieve the above object, a square cross section shield excavator according to a first aspect of the present invention is provided with a skin plate having a substantially square cross section, and the skin plate is disposed inside the skin plate. A circular crank wheel rotatably supported by the skin plate with the center of the center of rotation as the center of rotation and a predetermined distance from the crank wheel forward inside the skin plate, and the center of the skin plate is rotated. A circular rotary partition wall rotatably supported by the skin plate as a center, a position eccentric to the center of the crank ring by a certain amount, and a position eccentric to the center of the rotary partition by the certain amount. A rotation shaft supported by, a substantially equilateral triangular cutter head fixed to the tip of the rotation shaft, an external gear fixed to the rotation shaft, The core is fixed to the skin plate such that its center coincides with the center of the skin plate, the diameter of the pitch circle is approximately 4/3 times the diameter of the pitch circle of the external gear, and the external gear is And an internal gear that meshes with the gear, and a drive device that is fixed to the skin plate and that rotationally drives the crank wheel.

Further, a square-section shield excavator according to a second aspect of the invention is the square-section shield excavator according to the first aspect, which is arranged inside the skin plate and has a circle centered on the center of the skin plate. A hole is drilled, a support wall that rotatably supports the crank ring in the circular hole, and a predetermined distance from the support wall to the inside of the skin plate are provided at the center of the skin plate. A circular hole as a center is formed, a first fixed partition wall that rotatably supports the rotary partition wall in the circular hole, and is arranged between the first fixed partition wall and the cutter head. A second fixed partition wall in which an earth pressure chamber is formed between the rotary partition wall and the rear surface, and
An earth discharge port provided in the second fixed partition wall for passing an object to be excavated from the earth pressure chamber to the chamber, a mud pipe for sending mud from the outside into the chamber, and an object to be excavated in the chamber. It is characterized by being provided with a mud discharge pipe for discharging muddy water to the outside.

[0008]

According to the square-section shield excavator of the first aspect, when the crank wheel is rotationally driven by the drive device fixed to the skin plate, the crank wheel is eccentric to the center of the skin plate by a certain amount. The rotation shafts rotatably supported at positions and at positions decentered by a certain amount with respect to the center of the skin plate of the rotary partition wall revolve around the center of the skin plate. Therefore, the external gear fixed to the other end of the rotary shaft meshes with the internal gear, and revolves while revolving. Therefore, the rotating shaft also rotates while revolving around the center of the skin plate.
The cutter head having a substantially equilateral triangle shape fixed to the tip of the rotary shaft excavates earth and sand and gravel. At this time, in the cutter head, the diameter of the pitch circle of the external gear and the diameter of the pitch circle of the internal gear have a ratio of 3: 4,
According to the planetary motion of the rotating shaft, the envelope of the trajectory of the cutter head having a substantially equilateral triangle shape becomes a substantially square shape, and the cutter head excavates the earth and sand and gravel into a substantially square shape.

Therefore, the excavation of the ground into a substantially square shape by the cutter head and the cross section of the skin plate having a substantially square shape are combined with each other, so that the horizontal hole having a substantially square section can be excavated.

Further, since a large bending moment acting on the rotary shaft via the cutter head during excavation is supported by the rotary partition wall and the crank ring, the rotary shaft can smoothly rotate without bending.

Further, since the rotary shaft revolves by the drive device via the crank wheel, this square-section shield excavator can have a simpler structure and a shorter length as compared with, for example, one using a crank mechanism. Further, since the machine length of this square section shield excavator is shortened, the advancing angle can be changed to a larger angle than before, and it becomes easy to carry out a curve.

According to the square-section shield excavator of the second aspect, in the square-section shield of the first aspect, the circular hole of the support wall disposed inside the skin plate allows the crank ring to rotate. As well as supporting
A circular hole in the first fixed partition wall, which is disposed inside the skin plate and at a predetermined distance from the support wall in the front direction, rotatably supports the rotary partition wall. On the other hand, the earth and sand and gravel excavated by the cutter head substantially fills the earth pressure chamber between the cutter head and the second fixed partition wall, and the earth and sand and gravel accumulated in the earth pressure chamber are partially It passes through the earth discharging port provided in the second fixed partition and enters the chamber between the second fixed partition and the rotary partition. Then, the earth and sand and the gravel in the chamber are agitated with the muddy water sent from the mud pipe, and then discharged from the mud pipe to the outside.

As described above, since the rotary shaft is rotatably supported by the rotary partition wall and the rotary partition wall is rotatably supported by the first fixed partition wall, while allowing the planetary motion of the rotary shaft, The chamber side and the drive unit side in the skin plate can be tightly partitioned. Therefore, it is possible to prevent the muddy water in the chamber and the agitated earth and sand or gravel from entering the drive device side in the skin plate.

Further, since the earth and sand and the gravel accumulated in the earth pressure chamber press the face of the ground faced by the cutter head,
It is possible to prevent the face part of the ground from collapsing.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A square-section shield excavator of the present invention will be described in detail below with reference to an embodiment.

FIG. 1 is a cross-sectional view of a square-section shield excavator according to an embodiment of the present invention, in which 1 is a skin plate having a substantially square cross-section, 2 is an inner side of the skin plate 1, and A support wall 3 having a circular hole 2a centered on the center of the skin plate 1 is a circular hole 2 of the support wall 2.
A circular crank ring 4 fitted in a and rotatably supported in a circular hole 2a of the support wall 2 via a support member 6 has a predetermined space inside the skin plate 1 in front of the support wall 2. A first fixed partition wall 5 which is arranged open and has a circular hole 4a centered on the center of the skin plate 1 is fitted into the circular hole 4a of the first fixed partition wall 4 and is rotatably supported in a circular shape. It is a rotary partition. A rotary shaft 15 is rotatably supported at a position eccentric to the center of the crank ring 3 and a position eccentric to the center of the rotary partition wall 5, respectively. A cutter head 20 is fixed to one front end of the rotary shaft 15. Then, the second fixed partition 16 is fixed inside the skin plate 1 between the rotary partition 5 and the cutter head 20, and the rotary shaft 1 is attached to the second fixed partition 16.
A circular earth discharge port 17 through which 5 passes is formed. An earth pressure chamber 45 is formed between the front surface of the second fixed partition wall 16 and the cutter head 20, and a chamber 46 is formed between the rear surface of the second fixed partition wall 16 and the rotary partition wall 5. On the other hand, an external gear 31 is fixed to a portion of the rotary shaft 15 between the crank ring 3 and the rotary partition wall 5. A cylindrical internal gear 32 is fixed to the support plate 12 fixed to the inside of the skin plate 1 so as to mesh with the external gear 31 and the center thereof coincides with the center of the skin plate 1. The eccentric ring gear device 3 includes the external gear 31 and the internal gear 32.
Configures 0.

As shown in FIGS. 1 and 5, the crank ring 3 has a cylindrical portion 3a extending axially rearward from the outer periphery, and an internal gear 3b is formed on the inner periphery of the cylindrical portion 3a. is doing. A bracket portion 6a extending inward in the radial direction is formed from an upper portion of the rear end surface of the support member 6, and an electric motor 42 as a drive device is attached to the bracket portion 6a. Then, the internal gear 3b formed on the inner circumference of the cylindrical portion 3a meshes with the drive gear 44 which is fitted and fixed to the drive shaft 43 of the electric motor 42, and the electric motor 42 rotationally drives the crank wheel 3. I am trying.

As shown in FIG. 1, the rotary partition wall 5 has a disk portion 3 having a diameter smaller than that of the circular hole 4a of the first fixed partition wall 4.
4, a first cylindrical portion 35 that is fixed at a position eccentric to the center of the disc portion 34 by a certain amount, and rotatably supports the rotating shaft 15 via a bush (not shown), and the disc portion. A second cylindrical portion 36 that extends from the outer periphery of 34 to the support plate 12 side and has an outer diameter that is the same as that of the disk portion 34, and the second cylindrical portion 36.
From the second cylindrical portion 36 to the support plate 12 side, and the inner circumference has the same diameter as the inner circumference of the second cylindrical portion 36 and the outer circumference is smaller than the second cylindrical portion 36.
6a, and a fourth cylindrical portion 37, which is externally fitted and fixed to the outer periphery of the disc portion 34 and the outer periphery of the second cylindrical portion 36, and whose rear end face is close to the support plate 12. The second cylindrical portion 36
The bearing 10 is arranged between the step portion of the third cylindrical portion 36a and the fourth cylindrical portion 37 and the support plate 12, and the rotary partition wall 5 is rotatably supported by the support plate 12 via the bearing 10. There is. The bearing 10 can support both the thrust load and the radial load acting on the rotary partition wall 5. In addition, a cylindrical support member 38 is fixed between the first fixed partition wall 4 and the support plate 12, and between the inner peripheral surface of the support member 38 and the outer peripheral surface of the fourth cylindrical portion 37 of the rotary partition wall 5. Are sealed by a seal member 11. Further, as shown in FIG. 4, on the wall surface of the rotary partition wall 5 that faces the front of the disk portion 34, three first stirring blades are radially arranged at every 90 degrees as the rotation angle of the rotary partition wall 5. 39, and functions to agitate gravel, earth and sand, etc. in the chamber 46 between the rotary partition wall 5 and the second fixed partition wall 16.

As shown in FIGS. 1 and 2, the cutter head 20 has a key 28 at the tip of the rotary shaft 15.
The cylindrical portion 26 fixed by (shown in FIG. 3), three cutter arms 21 fixed to the cylindrical portion 26 at equal intervals in the circumferential direction, and extending in the radial direction, and the cutter arm 21.
And a cutter ring 22 having a small curvature that connects the vicinity of the tip of the. The second stirring blade 23 shown in FIG. 1 is fixed to the back surface of the cutter arm 21.
One or two cutter bits 24 are arranged at different positions in the radial direction on the front surface of the cutter arm 21, while one outer peripheral bit 25 is arranged at the center of the front surface of the cutter ring 22. There is. The apex A of each of the cutter arms 21 is located substantially outside the skin plate 1 having a substantially square cross section, and the apex A of each of the cutter arms 21 is connected to form an equilateral triangle.

As shown in FIGS. 1 and 3, the second fixed partition wall 16 is provided with a circular soil outlet 17 centered on the center of the skin plate 1. Then, a circular slit plate 18 having a diameter larger than that of the soil discharge port 17 is externally fitted and fixed to the cylindrical portion 26 to close the soil discharge port 17 from the rotary partition wall 5 side. An opening (not shown) that connects the earth pressure chamber 45 and the chamber 46 is formed in the slit plate 18, and the opening efficiency is adjusted by the size, shape, and number of the openings to change the earth pressure chamber 45 to the chamber 46. The amount of sediment and gravel entering the room is adjusted. It should be noted that the revolving motion of the rotary shaft 15 penetrating the soil discharge port 17 described below will prevent the outer peripheral surface of the cylindrical portion 26 fixed to the rotary shaft 15 from contacting the inner peripheral surface of the soil discharge port 17. Tsuchiguchi 17
The diameter of is set.

On the other hand, in the eccentric ring gear device 30, the radius of the pitch circle of the internal gear 32 and the external gear 31 shown in FIG.
The ratio of the radius of the pitch circle is set to 4: 3, and the center of the internal gear 32 is located at the center of the skin plate 1. For example, the radius R1 of the pitch circle of the internal gear 32 is
4. If the radius R2 of the pitch circle of the external gear 31 is R2 = 3,
The rotary shaft 15 and the external gear 31 are the skin plate 1
This means that the center is eccentric by an eccentric amount e = 1.
Further, this eccentricity e = 1, radius R1 = 4, radius R2 = 3
At this time, as shown in FIG. 2, the length S of one side of the skin plate 1 is S = 14, and the length S of one side of an equilateral triangle connecting the apex A of the cutter arm 21 is S = 14.

Further, in FIG. 1, a ring flange 50 is arranged inside the skin plate 1 rearward from the crank ring 3 with a predetermined space, and the square-section shield excavator is dug into the ring flange 50. A propulsion jack 51 for mounting is attached. In addition, inside the skin plate 1 behind the propulsion jack 50,
Outer peripheral surface of lined segment 60 and skin plate 1
A tail seal 55 that seals between the inner peripheral surface of the skin plate 1 and the inner peripheral surface of the skin plate 1 is arranged to prevent water and the like from entering the skin plate 1 from the outside. Further, an injection pipe 52 penetrating the support plate 12, the first fixed partition wall 4 and the second fixed partition wall 16 is provided on the upper side in the skin plate 1, and from the injection pipe 52 to the upper side of the skin plate 1 of the second fixed partition wall 16. A mudizing agent such as bentonite is injected into the earth pressure chamber 45 through an opening 52a (shown in FIG. 3) provided in a wide area near the corner. Further, in FIGS. 1 and 4, the skin plate 1 of the first fixed partition wall 4 is provided below the skin plate 1.
The mud feed pipe 53 for guiding muddy water into the chamber 46 through the opening 53a provided in a wide area near one corner on the lower side, and the other corner on the lower side of the skin plate 1 of the first fixed partition wall 4. Opening 54a provided in a wide area in the vicinity
A sludge pipe 54 for discharging the earth and sand and gravel as the object to be excavated in the chamber 46 to the outside.

The square cross section shield excavator having the above construction is
In FIG. 1, while pushing the front end of the segment 60 that has been restored to the rear with the propulsion jack 51 to propel the electric motor 4,
2 by the drive gear 44 and the internal gear 3b of the crank wheel 3
When the crank wheel 3 is rotated via the
A rotary shaft 15 rotatably supported by the rotary partition wall 5 rotates around the center of the skin plate 1. Therefore, the external gear 31 fixed to the rotary shaft 15 is
When the crank wheel 3 makes three revolutions, it rotates once, and while rotating, it revolves in the opposite direction three times. Due to the planetary motion of the external gear 31, the rotary shaft 15 and the cutter head 20 also perform one rotation while the crank ring 3 makes three revolutions, and revolves in the opposite direction three times to perform the planetary motion.

On the other hand, the radius R1 of the pitch circle of the internal gear 32 of the eccentric ring gear device 30 is R1 = 4, the radius of the pitch circle of the external gear 31 is R2 = 3, the eccentricity e of the rotary partition wall 5 = 1, and the cutter arm 21. Length S of one side of an equilateral triangle connecting the vertices A of
= 14, and the length S of one side of the skin plate 1 = 14
Therefore, the cutter arm 21 of the cutter head 20 is
The locus of an equilateral triangle formed by connecting the tips A of
As shown in FIG. 7, the skin plate 1 has a substantially square shape that matches the outer shape of the skin plate 1. Therefore, the cutter head 20
Excavates a substantially square lateral hole conforming to the outer shape of the skin plate 1.

Then, the excavated earth and sand and gravel are accumulated in a state of substantially filling the earth pressure chamber 45 between the cutter head 20 and the second fixed partition wall 16 and hold down the face of the ground faced by the cutter head 20. So that the ground face part does not collapse. Further, a mudizing agent such as bentonite is injected into the earth pressure chamber 45 through the opening 52a of the injection pipe 52, and earth and sand and gravel in the earth pressure chamber 45 are agitated by the second agitating blade 23 of the cutter head 20. Into a plastic flow state. The sand and gravel in this plastic flow state press the surface of the face of the ground with the pressure of the whole. Then, a part of the earth and sand and the gravel accumulated in the earth pressure chamber 45 sequentially enter the chamber 46 through the earth discharge port 17 of the second fixed partition wall 16 and the opening (not shown) of the slit plate 18. . The earth and sand and gravel in the chamber 46 are stirred by the first stirring blade 39 of the rotary partition wall 5 together with the muddy water introduced from the opening 53a of the mud feeding pipe 53,
It is discharged to the outside through the drainage pipe 54 from the opening 54a.

As described above, since the tip of the cutter arm 21 of the cutter head 20 excavates the ground in front while drawing a substantially square locus, the outer shape of the skin plate 1 is combined with the substantially square shape. It is possible to drill a substantially square lateral hole.

Further, since the electric motor 42 rotates the crank ring 3 via the internal gear 3b of the crank ring 3 and the drive gear 44, the external gear 31 can be planet-moved.
For example, a long-length transmission mechanism such as a crank mechanism is unnecessary. Therefore, the structure of this square-section shield excavator can be simplified and the machine length can be shortened. In addition, since the machine length of the square-section shield excavator is shortened, the advancing angle can be largely changed by the direction correction jack (not shown), and the lateral hole curve can be easily implemented.

When excavating the ground, a large bending moment acting on the rotating shaft 15 which makes a planetary motion supports the rotating shaft 15 by the crank ring 3 and the rotating partition wall 5, so that the rotating shaft 15 is bent. It can rotate smoothly without.

Further, the earth and sand and the gravel which are substantially filled in the earth pressure chamber 45 can press the face of the ground faced by the cutter head 20 to prevent the face of the ground face from collapsing.

The rotary shaft 15 is rotatably supported at a position eccentric to the rotary partition wall 5, and the rotary partition wall 5 is rotatably supported in the circular hole 4a of the first fixed partition wall 4. , Even if the rotating shaft 15 makes a planetary motion, the rotating partition wall 5
The first fixed partition wall 4 can tightly partition the chamber 46 side and the eccentric ring gear 30 side. Therefore, it is possible to prevent the sand and gravel mixed with the muddy water in the chamber 46 from entering the eccentric ring gear device 30 side in the skin plate 1.

In the above-described embodiment, the crank wheel 3 is rotated by the electric motor 42 via the internal gear 3b of the crank wheel 3 and the drive gear 44. However, a force for rotating the crank wheel 3 from a driving device such as an electric motor is applied to the crank wheel. It goes without saying that the transmission mechanism for transmitting is not limited to this.

Further, in the above embodiment, the mud additive such as bentonite was injected into the earth pressure chamber 45 through the injection pipe 52, but the mud additive is not required depending on the nature of the ground,
In that case, the mud additive may not be injected or the injection pipe may not be provided.

[0033]

As is apparent from the above, the square-section shield excavator of the first aspect of the invention has a circular crank ring disposed inside a skin plate having a substantially square cross-section, and the crank ring is used as a skin plate. The center of rotation is rotatably supported, and a circular rotary partition is arranged inside the skin plate at a predetermined distance from the crank ring in front of the skin. The rotary partition is rotated about the center of the skin plate. The rotary shaft is rotatably supported at a position eccentric to the center of the crank ring and at a position eccentric to the center of the rotary partition wall at the tip of the rotary shaft. An approximately equilateral triangular cutter head is fixed, an external gear is fixed to the rotary shaft, and an internal gear whose pitch circle diameter is approximately 4/3 times the diameter of the pitch circle of the external gear is used as an external gear. While if the center of the internal gear is fixed to the skin plate to match the skin plate, to fix the driving device to the skin plate, in which rotates the crank wheel by the driving device.

Therefore, according to the square-section shield excavator of the first aspect of the invention, when the crank wheel is rotationally driven by the driving device, the rotary shaft rotatably supported by the crank wheel and the rotary partition wall is the center of the skin plate. Revolve around. By the revolution of the rotary shaft, the external gear is revolved while meshing with the internal gear, and is rotated in a direction opposite to the revolution direction. Then, the rotary shaft fixed to the external gear and the cutter head are revolved while rotating. For this reason, the cutter head having the substantially equilateral triangle shape makes a planetary motion, and the envelope of the trajectory of the equilateral triangle connecting the vertices of the cutter head to each other becomes a substantially square shape, so that the ground can be excavated in a substantially square shape. Therefore, the excavation of the ground into a substantially square shape by the cutter head and the cross section of the skin plate having a substantially square shape are combined with each other, so that the horizontal hole having a substantially square section can be excavated.

Further, since a large bending moment acting on the rotary shaft via the cutter head during excavation is supported by the crank ring and the rotary partition wall, the rotary shaft can smoothly rotate without bending.

Further, since the above drive device does not require a long transmission mechanism for rotationally driving the crank wheel and driving the external gear by using the crank shaft or the like, the structure of this square section shield excavator can be simplified. It is possible and the captain can be shortened. Further, since the machine length of this square section shield excavator is shortened, the advancing angle can be changed to a larger angle than before, and it becomes easy to implement the curve of the lateral hole.

The square-section shield excavator according to the invention of claim 2 is the square-section shield excavator according to claim 1, wherein a support wall is arranged inside the skin plate, and the skin plate of the support wall is A circular hole centered on the center is bored to rotatably support the crank ring in the circular hole of the support wall, and first fixed inside the skin plate at a predetermined distance in front of the support wall. A partition is disposed, a circular hole centered on the center of the skin plate is formed in the first fixed partition, and the rotary partition is rotatably supported in the circular hole of the first fixed partition. A second fixed partition is arranged between the cutter head and the cutter head, an earth pressure chamber is formed between the cutter head and the front surface of the second fixed partition, and a chamber is provided between the rotary partition and the rear surface of the second fixed partition. Forming the second above An earth discharge port is provided in the constant partition wall to pass the material to be excavated from the earth pressure chamber to the chamber, and mud is sent from the outside to the chamber by a mud pipe, while the material to be excavated and mud in the chamber is discharged from the mud pipe. Is discharged from the outside.

Therefore, according to the square-section shield excavator of the second aspect of the invention, the rotary shaft is rotatably supported by the rotary partition wall, and the rotary partition wall is rotatably supported by the first fixed partition wall. While allowing the planetary motion of the rotary shaft, the chamber side and the drive unit side in the skin plate can be tightly partitioned. Therefore, it is possible to prevent the muddy water in the chamber and the agitated earth and sand or gravel from entering the drive device side in the skin plate.

Further, a part of the earth and sand and gravel in the earth pressure chamber enters the chamber in order from the earth discharge port of the second fixed partition wall, and the earth and pressure chamber is always filled with the amount of earth and sand and gravel. It will be in the accumulated state. Therefore, since the cutter head presses the face of the ground face facing the cutter head by the soil and gravel accumulated in the earth pressure chamber, it is possible to prevent the face face of the ground from collapsing.

[Brief description of drawings]

FIG. 1 is a sectional view of a square-section shield excavator according to an embodiment of the present invention.

FIG. 2 is a view seen from a line II-II in FIG.

FIG. 3 is a view seen from a line III-III in FIG. 1.

FIG. 4 is a view seen from line IV-IV in FIG. 1.

5 is a view seen from the line VV in FIG. 1. FIG.

6 is a view as seen from the line VI-VI in FIG. 1.

FIG. 7 is an explanatory view showing excavation of a square lateral hole by the cutter head performing a planetary motion.

[Explanation of symbols]

1 ... Skin plate, 2 ... Support wall, 3 ... Crank wheel, 4
... First fixed partition wall, 5 ... Rotating partition wall, 6 ... Support member, 10 ...
Bearing, 11 ... Sealing member, 12 ... Support plate, 15 ...
Rotating shaft, 16 ... Second fixed partition wall, 17 ... Soil discharge port, 18 ... Slit plate 20, Cutter head, 21 ... Cutter arm, 22 ... Cutter ring, 23 ... Second stirring blade, 26 ...
Cylindrical part, 28 ... Key, 30 ... Eccentric ring gear device, 31
... external gear, 32 ... internal gear, 34 ... disk part, 35 ... first cylindrical part, 36 ... second cylindrical part, 36a ... third cylindrical part, 3
7 ... 4th cylindrical part, 38 ... Support member, 39 ... 1st stirring blade, 42 ... Electric motor, 43 ... Drive shaft, 44 ... Drive gear, 5
0 ... Ring flange, 51 ... Propulsion jack, 52 ... Injection pipe, 53 ... Mud pipe, 54 ... Mud pipe, 55 ... Tail seal, 60 ... Segment.

Claims (2)

[Claims] 1. A skin plate having a substantially square cross section, a circular crank ring arranged inside the skin plate and rotatably supported by the skin plate about a center of rotation of the skin plate, and the skin. A circular rotary partition wall, which is disposed inside the plate at a predetermined distance from the crank ring and is rotatably supported by the skin plate about the center of the skin plate, and a center of the crank ring. A rotary shaft rotatably supported at a position eccentric to the center of the rotary partition and a eccentric position eccentric to the center of the rotary partition wall, respectively, and a cutter head having a substantially equilateral triangle shape fixed to the tip of the rotary shaft. And an external gear fixed to the rotary shaft, and fixed to the skin plate so that its center coincides with the center of the skin plate. In addition, the diameter of the pitch circle is approximately 4/3 times the diameter of the pitch circle of the external gear, and the internal gear that meshes with the external gear is fixed to the skin plate. A square-section shield excavator, which is provided with a drive device that rotates. 2. The square-section shield excavator according to claim 1, wherein the square-section shield excavator is arranged inside the skin plate,
A circular hole centered on the center of the skin plate is drilled,
A support wall that rotatably supports the crank ring in the circular hole, and a circular hole that is disposed inside the skin plate in front of the support wall with the predetermined interval, and that has a center of the center of the skin plate. And a first fixed partition wall that rotatably supports the rotary partition wall in the circular hole, and is disposed between the first fixed partition wall and the cutter head, and earth pressure is applied between the cutter head and the front surface. A second fixed partition wall that forms a chamber and forms a chamber between the rotary partition wall and the rear surface;
An earth discharge port provided in the second fixed partition wall for passing an object to be excavated from the earth pressure chamber to the chamber, a mud pipe for sending mud from the outside into the chamber, and an object to be excavated in the chamber. A square-section shield excavator characterized by comprising a mud discharge pipe for discharging mud and the outside.