JP2001065291A - Inclined cutter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent consolidation of excavated earth and sand between cutter bits by arranging the length of plural cutter bits arranged on the tip of a shield machine so as to become long toward the radial directional outside. SOLUTION: The shield machine 1 has a shielding body 4 composed of a shielding frame 2 formed in a cylindrical shape and a partition wall 3 for longitudinally partitioning the inside. In front of a cutter spoke 16, a distance L between a front end working face 18 of cutter bits 17 and a front face of the cutter spoke 16 is constituted so as to become long toward the radial directional outside. Thus, since a degree of consolidation of excavating earth and sand between cutters 15 becomes toward the radial directional outside, the excavating earth and sand are successively made to flow to the lower directional outside of a degree of consolidation so as to prevent consolidation of the excavating earth and sand between the cutter bits 17.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inclined cutter for excavating ground at the tip of a shield machine.

[0002]

2. Description of the Related Art A shield machine comprises a shield body formed of a cylindrical shield frame and a partition wall for partitioning the inside of the shield frame back and forth. It is configured. The cutter is composed of a plurality of cut-spokes or face plates extending radially from a rotation axis, and is driven in a forward rotation direction or a reverse rotation direction by a drive motor. A plurality of cutter bits are attached to the front face of the cutter spoke or the face plate.

Conventionally, as shown in FIG. 4, a cutter spoke 51 or a face plate is positioned so as to be perpendicular to a rotation axis 52, and a plurality of cutters having the same length in the digging direction are provided on the front surface thereof. Bits 53 are provided at predetermined intervals in the radial direction.

[0004] By rotating the cutter spoke 51, the cutter bit 53 rotates together to excavate the face 54.

[0005]

However, in the above-mentioned cutter, when the excavated earth and sand is a highly viscous earthen layer,
The excavated sediment has poor fluidity and high adhesion, and the front load is applied to the excavated sediment located between the cutter bits 53 by the propulsion of the shield machine, so that the excavated sediment is solidified between the cutter bits 53. The surface of the earth and sand comes into contact with the excavation surface 54 to generate friction. For this reason, a large rotating torque of the cutter is required, and the excavation speed is reduced,
Or there was a problem that excavation stopped.

Accordingly, the present invention has been devised to solve the above-mentioned problem, and an object of the present invention is to provide a cutter which can prevent solidification of excavated earth and sand between cutter bits.

[0007]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a shield excavator in which a cutter rotatably provided at a tip of the shield excavator is inclined such that a radially outer side thereof is located rearward in the excavation direction. A plurality of cutter bits are provided on the front surface of the cutter such that the length in the excavation direction becomes longer as the cutter bit is positioned radially outward.

[0008] According to the above configuration, the distance between the cutting face located in front of the cutter bit and the front surface of the cutter becomes longer toward the outside in the radial direction. Lower. by this,
After the excavated sediment is flowed outward in the radial direction with low consolidation density,
Since it is flushed behind the cutter, the excavated earth and sand can be prevented from solidifying between the cutter bits.

It is preferable that the tip of each of the cutter bits is located on the same plane.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One preferred embodiment of the present invention will be described with reference to the accompanying drawings.

FIG. 1 is a side sectional view showing a shield excavator provided with an inclined cutter according to the present invention, FIG. 2 is a front view showing a shield excavator provided with an inclined cutter according to the present invention, and FIG. It is the principal part enlarged sectional view which showed embodiment of the inclined cutter which concerns on this invention.

First, the overall configuration of a shield machine will be described with reference to FIGS.

As shown in the figure, the shield machine 1 has a shield body 4 composed of a shield frame 2 formed in a cylindrical shape and a partition wall 3 partitioning the inside of the shield frame 2 back and forth. The shield frame 2 is provided with a propulsion jack 6 for moving the shield body 4 forward by taking a reaction force to the existing segment 5, and a screw conveyor 7 for transporting excavated earth and sand into the pit is attached to a lower portion of the partition wall 3. .

A cutter rotating body 9 driven by a driving motor 8 is mounted on the partition wall 3. The cutter rotating body 9 is provided with a bearing 11 provided on the partition wall 3, a rotating shaft 12 supported by the bearing 11, a mounting seat 14 provided at a front end thereof, and provided in a circumferential direction from the mounting seat 14. And the cutter 15. In the present embodiment, the cutter 15 is set at a predetermined angle (90
(A pitch), and is formed of a cut-spoke 16 extending radially outward.

The cut spoke 16 is inclined so that its radially outer side is rearward in the digging direction.

A plurality of cutter bits 17 are provided on the front surface of the cutter spoke 16 so as to extend forward so that the length in the direction of excavation becomes longer as the cutter bits 17 are positioned radially outward. That is, the cutting face 17 at the front end of the cutter bit 17
And the distance L between the front end of the cut-spoke 16 and the front side of the cut-spoke 16 is configured to be longer toward the outside in the radial direction. In the present embodiment, the tip of each cutter bit 17 is located on the same plane perpendicular to the excavation direction.

The tip of each cutter bit 17 is not limited to being located on the above-described vertical plane. Face 18 in front of cutter bit 17 and cut-spoke 16
If the distance from the front surface of the cutter bit 17 becomes longer toward the outside in the radial direction, the tip portion of each cutter bit 17 becomes the same umbrella-like surface slightly inclined forward or backward in the digging direction toward the outside in the radial direction. It may be located.

Next, the operation of the tilt cutter having the above configuration will be described.

To excavate using the shield excavator 1, the cutter 15 is rotated by the drive motor 8 while pushing the existing segment 5 with the propulsion jack 6.

Thus, the face 18 is excavated while the shield body 4 is propelled forward.

At this time, the excavated earth and sand first flows into a space 19 sandwiched between the face 18 and the front face of the cut-spoke 16 and the adjacent cutter bit 17, as shown in FIG.

Since the cutter 15 is propelled forward by the propulsion jack 6 in this space 19, a front load is applied from the face 18. As a result, the excavated earth and sand is compressed in the space 19, but since the tip of the cutter bit 17 is located on the same plane, the front load is uniform, and
Is configured to be wider on the radially outer side, thereby reducing the outer pressure density.

As a result, the excavated earth and sand that has flowed into the space 19 is sequentially flown outward with a low pressure density as indicated by the arrow in the figure, and flows behind the cut-spoke 16. Therefore, the excavated earth and sand can always maintain fluidity, and can be prevented from being consolidated without being compressed between the cutter bits 17.

Therefore, the excavated surface 18 does not come into contact with the solidified excavated earth and sand as in the prior art, and no friction is generated. Therefore, an increase in the rotational torque of the cutter 15 is prevented,
It is possible to prevent a decrease in the excavation speed or stop the excavation, thereby achieving efficient excavation.

In this embodiment, the cutter 1
Although the shield excavator 5 is constituted by the cut-spokes 16 as an example, the shield excavator 1 is also applicable to a shield excavator in which the cutter 15 is formed by an umbrella-shaped face plate having a radially central side projecting forward. It is.

[0026]

In summary, according to the present invention, the density of the excavated soil between the cutter bits can be reduced toward the outside in the radial direction. An excellent effect of preventing solidification between bits can be exhibited.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing a shield machine provided with an inclined cutter according to the present invention.

FIG. 2 is a front view showing a shield machine provided with the inclined cutter according to the present invention.

FIG. 3 is an enlarged sectional view of a main part showing an embodiment of the inclined cutter according to the present invention.

FIG. 4 is an enlarged sectional view of a main part showing a conventional cutter.

[Explanation of symbols]

 1 shield machine 15 cutter 17 cutter bit

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Takashi Nakane 11-1 Kitahama-cho, Chita-shi, Aichi F-term in the Aichi Plant of Harima Heavy Industries, Ltd. F-term (reference) 2D054 BA07 BB05

Claims (2)

[Claims] 1. A cutter rotatably provided at a tip of a shield excavator is tilted so that its radially outer side is located rearward in the excavating direction, and a plurality of cutter bits are positioned radially outward on a front surface of the cutter. The inclined cutter is provided so that its length in the direction of excavation becomes longer. 2. The inclined cutter according to claim 1, wherein a tip portion of each of the cutter bits is located on the same plane.