JP2831904B2 - Rectangular mud shield excavator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[0002]

2. Description of the Related Art Conventionally, there is the following shield excavator (Japanese Patent Application Laid-Open No. 63-247497). In this shield excavator, a funnel-shaped hood is fixed to a front end of a cylindrical skin plate, and a partition is fixed to the skin plate so as to be located behind the hood. A chamber is formed. A rotary shaft is rotatably fitted to the center of the partition wall, and a cutter head is fixed to the tip of the rotary shaft. The cutter head includes a cone fixed to the tip of the rotating shaft and a digging portion such as a cutter arm fixed to the tip of the cone. A crushing chamber is formed between the cone and the hood. Then, muddy water is supplied to the crushing chamber by a mud pipe, the ground is excavated by an excavating section, the excavated gravels are crushed in the crushing chamber, and the crushed gravels, earth and sand, etc. are guided from the crushing chamber to the chamber, Further, the exhaust gas is discharged to the outside by a mud pipe communicating with the chamber.

[0003]

Recently, when digging a horizontal hole for a pipeline having a square cross section, there has been a demand for excavating a horizontal hole having a square cross section in accordance with the shape of the pipeline. is there.

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

An object of the present invention is to provide a rectangular muddy shield excavator capable of excavating a horizontal hole having a square cross section.

[0006]

According to a first aspect of the present invention, there is provided a rectangular muddy water shield excavator according to the first aspect of the present invention, wherein a skin plate having a substantially square cross section is disposed inside the skin plate, and a front chamber is provided. While facing
A rotating partition rotatably supported by the skin plate about the center of the skin plate as a center of rotation, a stirring blade fixed to a wall of the rotating partition facing the chamber, and a center of the skin plate of the rotating partition. A rotary shaft rotatably supported at a position eccentric to the rotary shaft, a cutter head fixed to the tip of the rotary shaft and having a digging portion forming a substantially equilateral triangle, and an outer fixed to the other end of the rotary shaft. The tooth gear is fixed to the skin plate such that the center thereof is coincident with the center of the skin plate, and the diameter of the pitch circle is 4/3 of the diameter of the pitch circle of the external gear.
An internal gear that is doubled and meshes with the external gear;
A rectangular mud shield excavator comprising: a driving device for driving the rotary partition; a mud pipe for feeding mud from the outside into the chamber; and a mud pipe for discharging mud in the chamber to the outside. Machine.

According to a second aspect of the present invention, there is provided the rectangular muddy shield excavator according to the first aspect, further comprising a stirring blade fixed to a portion of the rotary shaft located in the chamber. It is characterized by.

[0008]

According to the rectangular muddy water shield excavator of the first aspect, when the driving device is driven, the rotary partition rotatably supported by the skin plate having a substantially square cross section rotates. The rotating shaft supported by the rotating partition wall at a position eccentric to the center, that is, the center of the skin plate, rotates 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 rotation axis also rotates while revolving around the center of the skin plate. That is, the rotating shaft performs a planetary motion of revolving while rotating while being eccentrically supported with respect to the center of the skin plate via the rotating rotating partition. An excavation part forming a substantially equilateral triangle of the cutter head fixed to the tip of the rotation shaft excavates earth and sand and gravel on the ground. At this time, the cutting part of the cutter head is
Since 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, the rotating shaft performs a planetary motion, and the envelope of the locus of the excavated portion is substantially square. . Also, excavated soil and gravels enter the chamber,
The agitating blade fixed to the wall surface on the chamber side of the rotary partition wall agitates the muddy water fed from the mud pipe. Then, the muddy water containing the agitated earth and sand and gravel is discharged to the outside through a drainage pipe.

Therefore, the cross section of the skin plate is substantially square, and a substantially square horizontal hole can be excavated.

The rotary partition is rotated by a driving device, so that the external gear fixed to the rotary shaft meshes with the internal gear to perform planetary motion. Therefore, the rectangular muddy water shield excavator can have a simpler structure and a shorter machine length than, for example, those using a crank mechanism. In addition, since the length of the rectangular muddy water shield excavator becomes shorter, the angle at which the excavation section advances can be changed to a larger angle than before.
Curve execution becomes easier.

Further, the stirring blade of the rotary partition rotates three times in the opposite rotation direction while the cutter head makes one rotation, so that the earth and sand and the gravels in the chamber can be efficiently stirred.

It is generally considered difficult to partition the inside of the skin plate between the cutter head side and the drive unit side at this point because the rotating shaft is in planetary motion. However, according to the present invention, the rotating shaft is rotatably supported at an eccentric position of the rotating partition, and the rotating partition is rotatably supported by the skin plate. The cutter head side and the drive unit side in the skin plate can be partitioned tightly.

[0013] According to the rectangular muddy water shield excavator of the second aspect, since the rectangular muddy water shield excavator of the first aspect is provided with the stirring blade fixed to a portion of the rotary shaft located in the chamber, Since the stirring blade of the rotating shaft makes one rotation in the opposite rotation direction while the stirring blade of the rotary partition makes three rotations, the earth and sand and the gravels introduced into the chamber are efficiently stirred.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A rectangular muddy water 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 rectangular muddy water shield excavator according to one embodiment of the present invention, wherein 1 is a skin plate having a substantially square cross section, and 2 is fixed inside the front end of the skin plate 1. A hood having an inner funnel shape and a substantially square outer periphery; 3, a ring-shaped support plate fixed inside the skin plate 1 at a predetermined distance from a rear end of the hood 2; Reference numeral 3 denotes a rotary partition wall rotatably supported via a bearing 11 about the center of the skin plate 1 as a rotation center. A chamber 16 is formed between the rotary partition 4 and the rear end of the hood 2. Then, the first cylindrical portion 6 is fixed at a position eccentric with respect to the center of the skin plate 1 of the rotary partition 4, and the rotary shaft 15 is inserted through the first cylindrical portion 6 and rotatably supported via a bush (not shown). I have. A cutter head 20 is fixed to one end of the rotating shaft 15 on the hood 2 side. On the other hand, an external gear 31 is fixed to the other end of the rotating shaft 15 on the support plate 3 side. The external gear 31 meshes with an internal gear 32 fixed to the inner periphery of the skin plate 1, and the external gear 31 and the internal gear 32 constitute an eccentric ring gear device 30.

The rotary partition 4 has a disk portion 4a, the first cylindrical portion 6 fixed to the disk portion 4a, and a second cylindrical portion extending from the outer periphery of the disk portion 4a to the support plate 3 side. Part 4b
And a third cylindrical portion 5 extending from the disk portion 4a to the support plate 3 on the inner periphery of the second cylindrical portion 4b. As shown in FIG. 4, a distance between the outer periphery of the first cylindrical portion 6 of the rotating partition 4 and the outer periphery of the disk portion 4a is provided on the wall surface of the disk portion 4a on the chamber 16 side of the rotating partition 4. The first stirring blade 7 is provided at the position where the maximum is largest in the radial direction, and functions to stir the gravel, earth and sand, etc. with the muddy water in the chamber 16. The rotating partition 4 is rotatably supported by the support plate 3 via a bearing 11 disposed on the inner periphery of the second cylindrical portion 4b. With this bearing 11, the radial load and the thrust load acting on the rotating partition 4 are reduced. Both can be supported. A seal member 13 seals between the second cylindrical portion 4b on the outer periphery of the rotary partition 4 and the spacer plate 12 fixed on the inner periphery of the skin plate 1 and having a substantially square outer periphery and a cylindrical inner periphery. ing. On the other hand, the third cylindrical portion 5 penetrates the inner periphery of the support plate 3 and forms an external gear 5a shown in FIG. 5 on the outer periphery on the eccentric ring gear device 30 side. The drive gear 4 meshed with the external gear 5a
The third cylindrical portion 5, that is, the rotating partition 4 is rotated by an electric motor 42 as a driving device via the first motor 1.

The cutter head 20 is shown in FIGS.
As shown in FIG. 5, a cylindrical portion 26 fixed to the tip of the rotary shaft 15 by a key 28, and three cutter arms 21 fixed to the cylindrical portion 26 at equal intervals in a circumferential direction and extending in a radial direction, The cutter arm 21 includes a cutter ring 22 having a small curvature, which connects substantially the distal end of the cutter arm 21.
The cutter arm 21 is provided on the rotary partition 4 side with the
Are provided for reinforcement. One or two cutter teeth 24 are arranged at different positions in the radial direction on the front surface of the cutter arm 21, and one outer peripheral bit 25 is arranged at the center of the front surface of the cutter ring 23. doing. The vertex A of each of the cutter arms 21 is a substantially square skin plate 1.
And the vertex A of the cutter arm 21 is connected to each other to form an equilateral triangle. Further, the chamber 1 of the cylindrical portion 26 of the cutter head 20 is formed.
The outer periphery facing 6 is provided with three second stirring blades 27 fixed at equal intervals in the circumferential direction and extending in the radial direction. That is, the rotation shaft 15 is connected to the second
Are provided.

On the other hand, the above-described eccentric ring gear device 30 has a structure in which the radius of the pitch circle of the internal gear 32 and the external gear 31 shown in FIG.
The ratio of the radii of the pitch circles is 4 to 3. 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 above-mentioned internal gear 32 =
4. If the radius R2 of the pitch circle of the external gear 31 is R2 = 3,
The rotating shaft 15 and the external gear 31 are connected to the skin plate 1.
Is eccentric from the center by the amount of eccentricity e = 1.
Further, this eccentricity e = 1, radius R1 = 4, radius R2 = 3
At this time, as shown in FIG. 2, the length of one side of the skin plate 1 is S = 14, and the length of one side of an equilateral triangle connecting the vertices A of the cutter arm is S = 14. The electric motor 42 is connected to the external gear 5 a of the third cylindrical portion 5 and the drive gear 41.
When the rotary partition wall 4 is rotated through the above, the external gear 31 of the eccentric ring gear device 30 meshes with the internal gear 32,
The external gear 31 can revolve while rotating on the inner periphery of the internal gear 32.

In FIG. 1, reference numeral 51 denotes a direction correcting jack for correcting the excavating direction of the rectangular muddy water shield excavator, and 52 denotes a skin plate 1 of the spacer plate 12.
4 is a mud pipe for guiding muddy water to the chamber 16 through an opening 53 shown in FIG. An opening 54 shown in FIG. 4 provided at a wide location near the corner of the skin plate 1 of the spacer plate 12 is a drain pipe (not shown) for discharging earth and sand in the chamber 16 to the outside.

The rectangular muddy water shield excavator constructed as described above operates as follows. First, this rectangular mud shield excavator is propelled forward through a buried pipe by a jack (not shown) provided at the bottom of a vertical hole.

When the rotary partition 4 is rotated by the electric motor 42 via the external gear 5a of the third cylindrical portion 5 and the drive gear 41 while the rectangular mud shield excavator is propelled forward, the rotary partition 4 is eccentric. The rotation shaft 15 rotatably supported at the position thus set rotates around the center of the skin plate 1. Therefore, the external gear 3 fixed to one end of the rotary shaft 15
1 is meshed with the internal gear 32 and rotates on its own.
One rotation is performed during rotation, and three revolutions in the direction opposite to the rotation are performed while rotating. 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 rotary partition wall 4 makes three rotations, and perform a planetary motion by revolving three times in the opposite direction. . 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, the radius R2 of the pitch circle of the external gear 31 is 3, the eccentricity e of the rotary partition 4, and the vertex A of the cutter arm 21. The length of one side of the equilateral triangle S = 14 and the length of one side of the skin plate 1 S = 14, the trajectory of the tip A of the cutter arm 21 of the cutter head 20 becomes as shown in FIG. , A substantially square shape suitable for the outer shape of the skin plate 1. Therefore, the excavation section such as the cutter arm 21 excavates a substantially square horizontal hole that matches the outer shape of the skin plate 1. The excavated earth and sand and gravel are guided into the chamber 16 filled with the muddy water guided from the opening 53 of the mud pipe 52. Thus, the gravel and the earth and sand introduced into the chamber 16 are stirred by the first stirring blade 7 of the rotary partition wall 4 and the second stirring blade 27 of the rotary shaft 15, and are discharged from the opening 54 through a drain pipe (not shown). Discharged to the outside.

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. , Can drill a substantially square horizontal hole.

Since the electric motor 42 rotates the rotary partition 4 via the external gear 5a of the third cylindrical portion 5 and the drive gear 41, for example, a crank mechanism for causing the external gear 31 to perform planetary motion. Such a transmission mechanism having a long overall length is not required. Therefore, the structure of this rectangular muddy water shield excavator can be simplified, and the machine length can be shortened. In addition, since the length of the rectangular muddy water shield excavator is shortened, the angle at which the excavating section is advanced by the direction correcting jack 51 can be greatly changed, and the curve of the horizontal hole can be easily performed.

The first stirring blade 7 of the rotary partition 4 is also provided.
During the rotation of the cutter head 20 once,
While rotating, the second stirring blade 2 of the rotating shaft 15
7 rotates one revolution in the direction opposite to the direction of the first stirring blade 7 of the rotary partition 4, that is, in the same rotation direction as the cutter head 20, so that the earth and sand and the gravels introduced into the chamber 16 can be particularly efficiently stirred. Can be.

Also, when excavating the ground, a large bending moment acting on the rotating shaft 15 which carries out planetary motion is supported by the rotating partition 4 which rotates while rotatably supporting the rotating shaft 15 at an eccentric position. From this rotation axis 1
5 can rotate smoothly without bending.

The rotary shaft 15 is rotatably supported at an eccentric position of the rotary partition 4 and the rotary partition 4 is rotatably supported by the skin plate 1. Therefore, the planetary motion of the rotary shaft 15 is achieved. And the eccentric ring gear device 30 with the chamber 16 in the skin plate 1
The side can be separated tightly. Therefore, it is possible to prevent the muddy water and the stirred gravels and earth and sand in the chamber 16 from entering the eccentric ring gear device 30 in the skin plate 1.

In the above embodiment, the rotary partition 4 is rotated by the electric motor 42 via the external gear 5a of the third cylindrical portion 5 and the drive gear 41. However, the rotary partition is rotated by a driving device such as an electric motor. The transmission mechanism for transmitting the force is not limited to this.

In the above embodiment, the eccentricity e of the rotary partition 4 is equal to 1, and the radius R1 of the pitch circle of the internal gear 32 is equal to R1 =
4. The radius R2 of the pitch circle of the external gear 31 is R2 = 3, and the length S of one side of an equilateral triangle connecting the vertex A of the cutter arm 21 is 14. The length S of this side and the amount of eccentricity By changing the ratio to e, it is possible to excavate a slightly deformed substantially square cross-sectional hole with each side curved inward or outward.

[0029]

As is apparent from the above description, the rectangular muddy water shield excavator according to the first aspect of the present invention has a rotating partition disposed inside a skin plate having a substantially square cross section, and the rotating partition is rotated about the center of the skin plate. The rotatable support is rotatably supported as a center, and a stirring blade is provided on the chamber-side wall surface of the rotatable partition. The rotatable shaft is rotatably supported at a position eccentric to the center of the skin plate of the rotatable partition. A cutter head having a digging portion that forms a substantially equilateral triangle is fixed to the tip of the external gear, and an external gear is fixed to the other end of the rotating shaft, and the pitch circle diameter is 4 times the diameter of the pitch circle of the external gear.
A third internal gear is meshed with the external gear, and the internal gear is fixed to the skin plate so that the center of the internal gear coincides with the skin plate. The muddy water is sent from a mud pipe into a chamber provided in front, and the muddy water in the chamber is discharged from a mud pipe.

Therefore, according to the rectangular muddy water shield excavator according to the first aspect of the present invention, when the rotary partition is driven by the driving device, the external gear is rotated while meshing with the internal gear by the rotation of the rotary partition. The revolving is performed in the opposite direction, and the rotating shaft and the cutter head fixed to the external gear are revolved while rotating. For this reason, the excavation part constituting the substantially equilateral triangle of the cutter head performs a planetary motion,
Since the trajectory of this approximately equilateral triangular excavation part is approximately square,
Combined with the skin plate having a substantially square cross section, a substantially square lateral hole can be drilled.

Further, since the above-described drive device does not require a long transmission mechanism for rotating the rotary partition and driving the external gear using a crankshaft or the like, the structure of the rectangular muddy shield excavator can be simplified. The captain can be shortened. Further, when the length of the rectangular muddy water shield excavator is shortened, the angle at which the excavation section advances can be changed more greatly, and the execution of the curve of the horizontal hole becomes easier.

Further, the stirring blade of the rotary partition rotates three times in the opposite rotation direction while the cutter head makes one rotation, so that the earth and sand and the gravels introduced into the chamber can be efficiently stirred. .

Also, during excavation, a large bending moment acting on the rotating shaft that is in planetary motion is supported by the rotating partition, so that the rotating shaft can rotate smoothly without bending.

The rotating shaft is rotatably supported at an eccentric position of the rotating partition, and the rotating partition is rotatably supported by the skin plate. The cutter head side and the drive unit side in the skin plate can be partitioned tightly.

According to a second aspect of the present invention, there is provided a rectangular muddy shield excavator according to the first aspect, further comprising a stirring blade fixed to a portion of the rotary shaft in the chamber.

Therefore, according to the rectangular muddy water shield excavator according to the second aspect of the present invention, the stirring blade of the rotating shaft is rotated in the reverse rotation direction while the stirring blade of the rotary partition rotates three times.
Due to the rotation, the earth and sand and the gravels introduced into the chamber can be stirred particularly efficiently.

[Brief description of the drawings]

FIG. 1 is a sectional view of a rectangular muddy water shield excavator according to one embodiment of the present invention.

FIG. 2 is a diagram viewed from the line II-II in FIG.

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

FIG. 4 is a view taken along line IV-IV in FIG.

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

FIG. 6 is a view as seen from line VI-VI of FIG. 1;

FIG. 7 is an explanatory view showing that a digging part forming an equilateral triangle performs a planetary motion to dig a square horizontal hole.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Skin plate, 2 ... Hood, 3 ... Support plate, 4 ... Rotating partition, 4a ... Disk part, 4b ... 2nd cylindrical part, 5 ... 3rd cylindrical part, 6 ... 1st cylindrical part, 7 ... 1st Stirring blades, 11 ... bearings, 12 ... spacer plates, 13 ... sealing members, 15
... Rotating shaft, 16 ... Chamber, 20 ... Cutter head, 2
DESCRIPTION OF SYMBOLS 1 ... Cutter arm, 27 ... Second stirring blade, 30 ... Eccentric ring gear device, 31 ... External gear, 32 ... Internal gear, 4
1 ... drive gear, 42 ... electric motor, 51 ... direction correction jack, 52 ... mud pipe.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) E21D 9/08 E21D 9/12

Claims (2)

(57) [Claims] 1. A skin plate having a substantially square cross section, disposed inside the skin plate, facing a front chamber, and rotatably supported by the skin plate about the center of the skin plate as a center of rotation. A rotary partition, a stirring blade fixed to a wall of the rotary partition facing the chamber, a rotary shaft rotatably supported at a position eccentric to the center of the skin plate of the rotary partition, and the rotary shaft. A cutter head having a digging portion fixed to the tip of the rotating shaft and forming a substantially equilateral triangle; an external gear fixed to the other end of the rotating shaft; and the skin plate having a center coincident with the center of the skin plate. And an internal gear that is 4/3 times the diameter of the pitch circle of the external gear and meshes with the external gear. A rectangular mud shield comprising: a driving device for driving the rotary partition; a mud pipe for feeding mud from the outside into the chamber; and a mud pipe for discharging mud in the chamber to the outside. Excavator. 2. A rectangular muddy water shield excavator according to claim 1, further comprising a stirring blade fixed to a portion of said rotary shaft located in said chamber.