JP2953657B1 - Cutter bits for shield machine - Google Patents

Abstract

A cutter bit mounted on a planetary cutter included in a cutter disk of a shield machine for excavating a tunnel having a rectangular cross section excavates not only on one or two surfaces but on the entire circumference. Because of the drilling performance, wear resistance,
In order to ensure durability, it has a specific structure. SOLUTION: A cutter bit 18 is composed of a base material portion 41 and a bit main body portion 42, and the bit main body portion 42 has a cross section 4.
It has an angular shape, a rake angle is set on each of the four surfaces, and a clearance angle is set on most of the tip end surface of the bit main body 42,
Four tip corners 43 are formed, and the carbide tips 44a,
4b and 44c are mounted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cutter bit of a shield machine, and more particularly, to a cutter bit provided on a cutter disk for mounting on a planetary cutter that performs planetary motion.

[0002]

2. Description of the Related Art A shield excavator is widely used as a drilling device for constructing various shield tunnels (water and sewage tunnels, subway tunnels, communication cable tunnels, tunnels for common ditch, etc.) by a shield method. ing. A conventional shield machine is configured to excavate a tunnel having a circular cross section while switching between a state of excavating while rotating a cutter disk in a normal direction and a state of excavating while rotating the cutter disk in a reverse direction.

[0003] A cutter bit of this type of shield machine is generally applied with a two-way excavation type cutter bit capable of excavating both when the cutter disk is rotated forward and reversely. -6795,
See JP-A-63-36593. However, a cutter bit that can be excavated only in one direction and a cutter bit that can be excavated only in another direction may be arranged in mutually opposite directions.

[0004] In recent years, a shield tunneling machine for a rectangular tunnel capable of excavating a tunnel having a rectangular cross section has been proposed and is being developed for practical use. For example, JP-A-10-6
In the shield machine described in Japanese Patent No. 1382, a front-side rectangular cross-section body member is provided as a skin plate, and a rectangular-section shield frame connected to a rear end thereof is provided. A cutter rotating drive means for rotating and driving the cutter disk, wherein the cutter disk is mounted on the disk body and the disk body, and revolves while rotating and rotating in synchronization with the rotation of the disk body.
And a pair of planetary cutters.

[0005] A planetary gear mechanism for rotating the planetary cutter in conjunction with the rotation of the disk body is provided, and the contour shape of the planetary cutter is formed in accordance with the ratio of the rotational speed of the planetary cutter to the rotational speed of the planetary cutter. The cross section tunnel can be excavated. The planetary cutter has a substantially leaf shape, and a plurality of cutter bits are mounted on an outer peripheral portion thereof.

In this shield machine, the ratio between the rotation speed and the revolution speed of the planetary cutter is set to 4: 1, and a circular cross section at the center of the tunnel is excavated with the main cutter of the disk body, and the circular shape is obtained. The portion overlapping the cross section and the four corners are excavated with a pair of planetary cutters. When the planetary cutter revolves while rotating, the plurality of cutter bits of the planetary cutter move while drawing a special free-curve trajectory to perform excavation.

[0007]

A cutter bit suitable for the shield tunnel machine for a rectangular tunnel has not yet been proposed. It is also conceivable to apply a cutter bit. However, since the plurality of cutter bits of the planetary cutter perform the excavation while drawing a special free curve, the cutter bits not only excavate on two surfaces but also excavate on a substantially entire surface. Therefore, it is necessary to apply a cutter bit having a special structure for efficiently excavating almost all over the surface as a cutter bit mounted on the planetary cutter.

It is an object of the present invention to provide a cutter bit suitable for mounting on the above-mentioned planetary cutter, and to provide a cutter bit which can be efficiently excavated on almost the entire circumference. .

[0009]

According to a first aspect of the present invention, there is provided a cutter bit for a shield excavator provided in a shield excavator having a disk body and a planetary cutter.
The cutter bit has a bit main body having a polygonal cross section, and at least the outer peripheral portion of the tip main body of the bit main body is made of a superhard member, and a rake angle is set on each face of the polygon of the bit main body. At the same time, a clearance angle is set on most of the tip end face of the bit body, and the tip of the bit body is
The part has a plurality of tips that protrude toward the distal end as
End corners are formed, and these tip corners are made of a carbide member.
It is characterized by having been done.

Since the planetary cutter revolves while rotating,
Each of the plurality of cutter bits mounted on the outer periphery of the planetary cutter moves along a special free curve to perform excavation. Therefore, excavation is performed almost all around the outer peripheral portion of each cutter bit. However, since the outer peripheral portion of at least the tip side portion of the bit main body portion is formed of a carbide member, wear resistance and durability are improved. And excavation performance is high. The bit body has a polygonal cross-section, and the rake angle is set on each face of the polygon of the bit body, so that the drilling performance on each face of the polygon of the cutter bit can be secured. Since the clearance angle is set at most of the end face of the portion, excavation performance can be ensured and the cutter bit can be prevented from overheating.

Since the plurality of tip corners project toward the tip end as they approach the plurality of corners, a clearance angle is secured through the plurality of tip corners, so that the excavation performance is improved and the excavated earth and sand is improved. Flow is also good, and overheating is also prevented.

According to a second aspect of the present invention, there is provided a cutter bit for a shield machine, wherein the cutter disk comprises a disk body and a planetary cutter.
Equipped with planetary cutter in shield machine with
The cutter bit
Has a polygonal cross-section bit body,
At least the outer peripheral portion of the distal end portion of the main body is made of a carbide member.
Rake angles are formed on each side of the polygon of the bit body.
Is set, and a large part of the tip surface of the bit body
A relief angle is set , and an inverted polygonal pyramid-shaped recess is formed at the tip of the bit main body. A relief angle can be set at most of the tip end face of the bit body through the inverted polygonal pyramid-shaped recess, and the excavation performance is enhanced through the inverted polygonal pyramid-shaped recess (that is, via the relief angle).
Overheating can be prevented. Others according to claim 1
The same operation as in the paragraph [0010] is achieved.

According to a third aspect of the present invention, there is provided a cutter bit for a shield machine, wherein the cutter disk comprises a disk body and a planetary cutter.
Equipped with planetary cutter in shield machine with
The cutter bit
Has a polygonal cross-section bit body,
At least the outer peripheral portion of the distal end portion of the main body is made of a carbide member.
Rake angles are formed on each side of the polygon of the bit body.
Is set, and a large part of the tip surface of the bit body
A relief angle is set, a predetermined length portion on the distal end side of the bit main body portion is formed of an integral cemented carbide member, and the distal end portion of the bit main body portion retreats away from the distal end as it approaches a plurality of corners. Are formed. As the tip valleys recede away from the tip as they approach the corners, a clearance angle is secured through the tip valleys, excavation performance is improved, and the flow of excavated sediment is reduced. It becomes better and also prevents overheating. So
In addition, the same operation as the paragraph [0010] according to claim 1 is performed.
Play.

[0014]

Embodiments of the present invention will be described below. First, a shield tunneling machine for a rectangular tunnel will be described, and then a cutter bit applied to a planetary cutter of the shield tunneling machine will be described. Figure 1,
As shown in FIG. 2, the shield machine 1 includes a body member 1a having a rectangular cross section and a shield frame 1b having a rectangular cross section connected to a rear side thereof. Section and a plurality of bent jacks 30. The cutter disk 2 is disposed on the front end side of the body member 1a.
And a pair of planetary cutters 5 mounted on the disk body 4
And an annular cutter drum 3 connected to the disk main body 4 by a plurality of connecting members 4b.

A cutter rotation drive mechanism 6 for rotating the disk body 4 and the cutter drum 3 is provided. A main cutter 4a is provided at the front end of the disk body 4, and the main cutter 4a rotates integrally with the disk body 4. The main cutter 4a is provided with a plurality of cutter bits 15. As shown in FIGS. 1 to 3, a planetary gear mechanism 7 for rotating each planetary cutter 5 in synchronization with the rotation of the disk body 4, that is, the rotation of the cutter drum 3, is provided inside the cutter drum 3. Of the planetary cutter 5
Is formed in a leaf shape according to the ratio between the rotation speed and the revolution speed.

On the rear side of the cutter disk 2, there is provided a partition wall structure 9 integrally fixed to the body member 1a with a chamber 8 interposed therebetween.
0, a central wall portion 10a, and an annular wall portion 11. The planetary gear mechanism 7 has a sun gear 12, a pair of idle gears 13 meshed with the sun gear 12, and a pair of planetary gears 14 meshed with the pair of idle gears 13, respectively.
Is formed along the outer periphery of the cylindrical body 10. The planetary cutter 5 and the planetary gear 14 are linked and connected by a planetary shaft 16.

The rear end 16a of the planetary shaft 16 and the planetary gear 14 are connected by a spline connection, and the front end 16b of the planetary shaft 16 and the planetary cutter 5 are connected via bolts. A planet housing 17 is provided on the planet shaft 16.

As shown in FIG. 1, the cutter rotation drive mechanism 6 has a ring gear 19 having internal teeth provided between the rear end of the cutter drum 3 and the annular wall portion 11, and rotationally drives the ring gear 19. Multiple cutter drive motors 20
It is composed of The ring gear 19 is fixed to the cutter drum 3 and is supported on the annular wall 11 via a slewing bearing. Each cutter drive motor 20 is composed of, for example, a hydraulic motor, and a pinion gear 20a fixed to the motor shaft.
Are in mesh with the ring gear 19. During tunnel excavation,
The rotation direction of the cutter disk 2 is reversed every time one ring is excavated.

The plurality of shield jacks 22 are for generating a thrust for excavation. Each shield jack 22 is disposed rearward, and the tip of the rod is spreader 22b via an eccentric fitting 22a. Are connected to each other, and the shield jack 22 generates a digging thrust by applying a reaction force to the segment 34 lining the inside of the tunnel. The main cutter 4a is provided with a copy cutter 23A and the one planetary cutter 5 is provided with a pair of copy cutters 23B in order to make the tunnel outer shape larger when the excavation direction of the rectangular tunnel is curved. The other planetary cutter 5 is provided with a copy cutter 23C.

A screw conveyor 28 extending rearward from the central wall 10a is provided as an earth discharging facility. The earth and sand in the chamber 8 is transferred to a belt conveyor in the shield frame 1b, and the earth and sand sent to the belt conveyor. Is transported to the rear in the tunnel by a belt conveyor or a transport cart and transported to the ground. An erector device 33 for assembling a segment on the inner surface of a tunnel having a rectangular cross section is also provided.

Regarding the planetary gear mechanism 7, in an excavator for excavating a tunnel having a rectangular cross section, the sun gear 12 and the idle gear 12 are set so that the ratio between the revolution speed and the revolution speed of the planetary cutter 5 is 1: 4. 13, the number of teeth of the planetary gear 14 is set. Therefore, each planetary cutter 5 has a disk body 4
It rotates once when it rotates a quarter turn. The rotation directions of the disk body 4 and the planetary cutter 5 are opposite.

The principle of excavating a rectangular cross-section tunnel by excavating a rectangular cross-sectional corner with each planetary cutter 5 by forming the contour shape of the planetary cutter 5 in a front view into a leaf shape of a tree, and excavating a corner of a rectangular cross-section with each planetary cutter 5 will be described. As shown in FIG. 4, the rectangular cross section of the tunnel is defined as a square h indicated by an imaginary line, and the tunnel machine 1 excavates the tunnel having this square cross section. A locus that always inscribes this square h must be drawn. Therefore, when the planetary cutter 5 rotates four times while revolving once, the trajectory of the farthest point from the orbital center O of the planetary cutter 5 becomes a square h.
The contour shape of the planetary cutter 5 is determined so as to draw.

Now, assuming that the revolution locus of the rotation center Ob of the planetary cutter 5 is a circle K, points m1, m2,.
Indicates the position of the rotation center Ob of the planetary cutter 5 at each angle θ when the planetary cutter 5 is rotated by an angle θ (θ = 15 °). Points P1, P2, ... on the square h
Is a point where a straight line connecting each point m1, m2,... On the circle K and the center of revolution O intersects the square h.

Here, when the rotation center Ob of the planetary cutter 5 is at the position of the point m1, the radius of the planetary cutter 5 must be the same as the point m1 on the circle K and the square in order to inscribe the planetary cutter 5 with the square h. It must be a straight line length n1 connecting the point P1 on h. When the planetary cutter 5 revolves from the position of the point m1 by the angle θ and moves to the position of the point m2, in order for the planetary cutter 5 to be inscribed in the square h, the radius of the planetary cutter 5 must be a point on the circle K. It must be a straight line length n2 connecting m2 and the point P2 on the square h.

Similarly, when the planetary cutter 5 moves to the position of the point m3, the radius of the planetary cutter 5 must be not the straight line length n3 connecting the point m3 on the circle K and the point P3 on the square h. No. On the other hand, the planetary cutter 5 rotates by an angle of 4θ while revolving by an angle of θ. As described above, by sequentially determining the radius length of the planetary cutter 5, the contour shape of the planetary cutter 5 is determined, and the contour shape of the planetary cutter 5 becomes a leaf shape of a tree.

When the planetary cutter 5 is equipped with, for example, 20 cutter bits 18 having a regular quadrangular cross section, FIGS. 5 to 11 show the freedom of the cutter bits 18 when the planetary cutter 5 revolves while rotating. It shows a curved movement locus. When the cutter bits 18 in the planetary cutter 5 are numbered No. 1 to No. 7,...
The movement trajectory of the cutter bit 18 is shown in FIGS. 5 to 11 show a case where the cutter disk 2 rotates counterclockwise and the planetary cutter 5 rotates clockwise, but the planetary cutter 5 may rotate in the opposite direction.

FIG. 12 shows the planetary cutter 5 shown in FIG.
The locus of movement of the No. 1 cutter bit 18 is enlarged, and the earth and sand excavated by the cutter bit 18 is L-shaped hatched mark 24
In view of the fact that the cutter bit 18 excavates while drawing a free curve like a streamlined outer shape, it is necessary to excavate almost all four surfaces of the cutter bit 18 as can be seen from FIG. Become. FIG. 13 is a diagram corresponding to FIG. 12 in a case where the cutter disk 2 rotates clockwise and the planetary cutter 5 rotates counterclockwise. In this case as well, FIG. Drilling will be performed on almost the entire surface.

Next, the cutter bit 18 applied to the planetary cutter 5 will be described. As shown in FIGS. 14 to 16, the cutter bit 18 has a base portion 41 as a mounting leg portion having a circular cross section, and a cross section that is slightly thicker than the base portion 41 and is integrally formed with the base portion 41. And a quadrangular bit body 42.

The cross section of the bit main body 42 perpendicular to the axis thereof is formed gradually larger toward the upper side, and the rake angle α is set on each of the square faces of the bit main body 42, and the bit main body 42 is A clearance angle β is set on most of the tip surface. At the tip of the bit body 42, four tip corners 43 projecting toward the tip side (upward in FIG. 15) as they approach the four corners 42a. A first blade 43a, a pair of second blades 43b, and a third blade 43c are formed at each of the corner portions 43.

Each of the four corner portions 43 near the corners is formed of a cemented carbide tip 44a (corresponding to a cemented carbide member) made of a cemented carbide material manufactured by powder molding of powder such as tungsten carbide. The outer peripheral portion of the tip side half of the bit main body 42 is also formed of four cemented carbide tips 44b (corresponding to cemented carbide members) made of the same hard material as described above. The protruding portion is also formed of a super hard tip 44c made of the same super hard material as described above. Thus, the four tip corners 43 are also made of a super hard material. Portions of the base portion 41 and the bit body portion 42 other than the carbide tips 44a to 44c are made of carbon steel. These carbide tips 44a-4
4c is bonded and fixed to a member made of carbon steel by brazing using a silver brazing material. In addition, this cutter bit 18
Is fixed to the outer peripheral member of the planetary cutter 5 by welding.

According to the cutter bit 18, since the outer peripheral portion of at least the distal end portion of the bit main body 42 is formed of the carbide tips 44a and 44b, the cutter bit 18 is excellent in wear resistance and durability. The rake angle α on each surface of the square of the bit body 42
Is set, excavation performance on each surface of the square of the cutter bit 18 can be secured, and excavation can be performed in all directions. Since the clearance angle β is set at most of the tip end surface of the bit main body 42, excavation performance can be secured, and the cutter bit 18
Can be prevented from overheating to ensure durability.

Further, the tip of the bit body 42 is
Four tip corners 4 protruding toward the tip as they approach two corners
3 are formed, and the main part of these tip corners 43 is formed of a carbide tip 44a.
As the corners 43a are protruded closer to the tip, the excavation performance is improved, the flow of the excavated soil is improved, and overheating is prevented. The cutter bit 18
The bit body 42 is formed in a quadrangular cross section, but is not limited to a quadrangular cross section, but is formed in a polygonal cross section such as a triangular cross section, a pentagonal cross section, or a hexagonal cross section. Of course, the number of the corner portions 43 may be plural according to the polygon.

Next, a cutter bit according to a modification will be described. Modification Example 1 (see FIGS. 17 to 19) As shown in FIGS. 17 to 19, the cutter bit 18A of Modification Example 1 includes a base member 51 as a mounting leg having a circular cross section, Slightly thicker than the material part 51 and the base part 51
And a bit main body 52 having a quadrangular cross section integrally formed with the main body.

The cross section of the bit body 52 perpendicular to its axis is formed gradually larger toward the top, and the rake angle α is set on each of the square faces of the bit body 52, and the bit body 52 is A clearance angle β is set on most of the tip surface. An inverted quadrangular pyramid-shaped recess 53 is formed at the tip of the bit body 52, and the clearance angle β is secured through the recess 53.

The outer peripheral portion of the tip end portion of the bit body 52 is made of a square frame-shaped carbide tip 5 made of the same carbide material as described above.
4 (corresponding to a super hard member). Base part 5
Parts other than the carbide tip 54 of the bit 1 and the bit body 52 are made of carbon steel. The carbide tip 54 is bonded and fixed to a carbon steel member by brazing using a silver brazing material. Also in this cutter bit 18A, basically,
The same effect as the above-mentioned cutter bit 18 is obtained, but the inverted quadrangular pyramid-shaped concave portion 53 is formed at the tip end of the bit main body portion 52. The clearance angle β can be set at most of the tip end surface of the portion 52, and the excavation performance is enhanced through the inverted pyramid-shaped recess 53 (that is, via the clearance angle β), and the overheating of the cutter bit 18A is reduced. Can be prevented.

Although the bit body 52 of the cutter bit 18A is formed in a quadrangular cross section, it is not limited to a quadrangular cross section, but may be formed in a triangular cross section, a pentagonal cross section, or a hexagonal cross section. It may be formed in a polygonal cross section such as
In this case, the inverted quadrangular pyramid-shaped concave portion 53 becomes an inverted polygonal pyramid-shaped concave portion.

Modification 2 (see FIGS. 20 to 22) As shown in FIGS. 20 to 22, the cutter bit 18B of this modification 2 has a base 61 as a mounting leg having a circular cross section. , The base member 61 is slightly thicker than the base member 61 and
And a bit main body 62 having a quadrangular cross-section integrally formed therewith.

The cross section of the bit main body 62 perpendicular to the axis thereof is formed gradually larger as it goes upward, and the rake angle α is set on each of the square faces of the bit main body 62 and the bit main body 62 is Negative clearance angle γ for most of the tip surface
Is set. An integral cemented carbide member 6 in which a predetermined length portion on the distal end side of the bit main body 62 is made of the same cemented carbide material as described above.
3, four tip troughs 64 are formed at the tip of the bit body 62 so as to move away from the tip as they approach the four corners 64a. A clearance angle γ is ensured at the tip end surface of 62.

The portion of the cutter bit 18B other than the super hard member 63 is made of carbon steel.
3 is provided with a boss-like projection 63a projecting from the center of the lower surface thereof. The boss-like projection 63a is fitted into a fitting recess formed in a member made of carbon steel. It is brazed to a member made of silver with a silver braze. This cutter bit 1
8B also has basically the same effect as the cutter bit 18, but since a predetermined length portion on the distal end side of the bit main body 62 is constituted by the integral superhard member 63,
Excellent wear resistance and durability.

At the tip of the bit body 62, four tip valleys 64 are formed to recede away from the tip as they approach the four corners 64a, and escape through the four tip valleys 64. The angle γ is secured, the excavation performance is improved, and the flow of excavated earth and sand is also improved, which also prevents overheating. The bit body 6 of the cutter bit 18B
2 is formed in a rectangular cross section, but is not limited to a rectangular cross section, and may be formed in a polygonal cross section such as a triangular cross section, a pentagonal cross section, and a hexagonal cross section. In that case, the number of the tip troughs 64 is also plural according to the polygon.

[0041]

According to the first aspect of the present invention, the cutter bit has the bit main body having a polygonal cross section, and at least the outer peripheral portion of the tip main body of the bit main body is formed of a cemented carbide member. Excellent wear resistance and durability. Since the rake angle is set on each face of the polygon of the bit main body, the excavation performance on each face of the polygon of the cutter bit can be secured, and excavation can be performed in all directions. Since the clearance angle is set at most of the tip surface of the bit body, excavation performance can be ensured, and the cutter bit can be prevented from overheating to ensure durability.

Further, a plurality of tip corners are formed at the tip end of the bit main body portion so as to protrude toward the tip as the corners approach the plurality of corners, and these tip corners are made of a cemented carbide member. Since the plurality of tip corners project toward the tip as they approach the plurality of corners, excavation performance is improved, and the flow of excavated earth and sand is improved, and overheating is also prevented .

According to the second aspect of the present invention, an inverted polygonal pyramid-shaped recess is formed at the tip of the bit main body.
The clearance angle can be set at most of the tip end face of the bit body through the inverted polygonal concave portion, and the excavation performance can be improved through the inverted polygonal concave portion (that is, via the clearance angle). , Overheating of the cutter bit can be prevented. The other effects are the same as those of the paragraph [0041] according to the first aspect.

According to the third aspect of the present invention, since the predetermined length portion on the tip end side of the bit main body is formed of an integral superhard member, the wear resistance and the durability are excellent. The tip of the bit body has a plurality of tip valleys that recede away from the tip as they approach multiple corners, ensuring a clearance angle through the multiple tip valleys and ensuring excavation performance. And the flow of excavated soil becomes better, which also prevents overheating. The other effects are the same as those of the paragraph [0041] according to the first aspect.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a rectangular tunnel machine according to an embodiment of the present invention.

FIG. 2 is a schematic front view of a cutter disk.

FIG. 3 is a schematic front view showing a planetary gear mechanism.

FIG. 4 is an explanatory diagram illustrating the principle of excavating a rectangular tunnel.

FIG. 5 is an explanatory diagram of a locus of motion of a No. 1 cutter bit of a planetary cutter.

FIG. 6 is an explanatory diagram of a movement locus of a No. 2 cutter bit of a planetary cutter.

FIG. 7 is an explanatory diagram of a motion locus of a No. 3 cutter bit of a planetary cutter.

FIG. 8 is an explanatory diagram of a locus of motion of a No. 4 cutter bit of a planetary cutter.

FIG. 9 is an explanatory diagram of a movement locus of a No. 5 cutter bit of a planetary cutter.

FIG. 10 is an explanatory diagram of a movement locus of a No. 6 cutter bit of a planetary cutter.

FIG. 11 is an explanatory diagram of a movement locus of a planetary cutter No. 7 cutter bit.

FIG. 12 is an explanatory diagram in which an L-shaped hatched mark is added to the enlarged view of a main part in FIG. 5;

FIG. 13 is an explanatory diagram similar to FIG. 12;

FIG. 14 is a front view of the cutter bit.

15 is a sectional view taken along line XV-XV in FIG.

FIG. 16 is a perspective view of a cutter bit.

FIG. 17 is a front view of a cutter bit according to a first modification.

18 is a sectional view taken along line XVIII-XVIII in FIG.

FIG. 19 is a perspective view of the cutter bit of FIG. 17;

FIG. 20 is a front view of a cutter bit according to a second modification.

21 is a sectional view taken along line XXI-XXI in FIG.

FIG. 22 is a perspective view of the cutter bit of FIG. 20.

[Explanation of symbols]

1 rectangular tunnel for the shield machine 2 cutter disk 4 disk body 5 planetary cutter 18 cutter bit 42 bit body portion 43 front end corner 44a, 44b, 44c carbide inserts 18A cutter bit 52 bit body 53 opposite quadrangular pyramid-shaped recesses 54 hard tip 18B cutter bit 62 bit body portion 63 superhard member 64 distal valleys

────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Akio Shiseki 1-7-1 Kyobashi, Chuo-ku, Tokyo Toda Construction Co., Ltd. (72) Inventor Toru Taniguchi 1-7-1 Kyobashi, Chuo-ku, Tokyo Toda Inside Construction Co., Ltd. (72) Yasushi Shibata, Inventor 1-7-1, Kyobashi, Chuo-ku, Tokyo Toda Construction Co., Ltd. (72) Inventor Makoto Enkawa 1-1-1, Kyobashi, Chuo-ku, Tokyo Toda Construction Co., Ltd. (56) References JP-A-10-61382 (JP, A) JP-A-10-115185 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) E21D 9/08 E21B 10 / 46

Claims (3)

(57) [Claims] 1. A cutter bit for mounting a cutter disk on a planetary cutter in a shield machine having a disk body and a planetary cutter, wherein the cutter bit has a bit body portion having a polygonal cross section. At least the outer peripheral portion of the distal end portion of the main body is formed of a superhard member, and a rake angle is set on each surface of the polygon of the bit main body, and a clearance angle is formed on a large part of the distal end surface of the bit main body. It is set, closer to the plurality of corner portions at the tip portion of the bit body portion Hodosaki
A plurality of tip corners projecting to the end side are formed, and these tip
A cutter bit for a shield machine, wherein a corner portion is made of a super hard member . 2. A disk comprising a cutter disk and a planet.
Planetary cutter in shield machine with cutter
In the cutter bit for equipping the cutter body, the cutter bit has a bit body portion having a polygonal cross section.
A, the outer peripheral portion of at least the distal portion of the bit body portion super
A rake angle is set on each face of the polygon of the bit main body , which is made of a hard member.
And a clearance angle is formed on most of the tip surface of the bit body.
A cutter bit for a shield machine , wherein an inverted polygonal pyramid-shaped recess is formed at a tip end of the bit body. 3. The cutter disk comprises a disk body and a planet.
Planetary cutter in shield machine with cutter
In the cutter bit for equipping the cutter body, the cutter bit has a bit body portion having a polygonal cross section.
A, the outer peripheral portion of at least the distal portion of the bit body portion super
A rake angle is set on each face of the polygon of the bit main body , which is made of a hard member.
And a clearance angle is formed on most of the tip surface of the bit body.
A predetermined length portion on the distal end side of the bit main body portion is formed of an integral cemented carbide member, and a plurality of tip valleys which recede away from the tip as approaching a plurality of corners at the distal end portion of the bit body portion. A cutter bit for a shield machine, wherein a part is formed.