JPH10246093A - Roller cutter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the falling of a carbide chip by fitting the carbide chip into a notch formed to the cutter edge section of a roller cutter body and brazing and fixing the carbide chip. SOLUTION: Press-fitting type carbide chips 18 and brazing carbide chips 20 are installed to the section of a cutter edge section 17 at regular intervals. The carbide chips 20 are fixed integrally onto the cutter edge section 17 and a roller cutter body 16 by a solder material at that time. Consequently, even when all press-fitting type carbide chips 18 are slipped off, the brazing carbide chips 20 can be left, and excavation capacity in a certain extent is maintained only by the brazing carbide chips 20. Since the brazing carbide chips 20 are formed in the same sectional shape as the cutter edge section 17 and side faces reach the side section of the edge section 17, the abrasion of the sections of the peripheries of the side faces of at least brazing carbide chips 20 is inhibited. Accordingly, the falling of the carbide chips mounted on the cutter edge section can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a roller cutter, and more particularly to a roller cutter capable of preventing a carbide tip attached to a cutter blade from falling off.

[0002]

2. Description of the Related Art Conventionally, shield excavators have been used to excavate tunnels in the soil.

As shown in FIG. 8, the shield machine described above is configured such that a face plate 3 on which a cutter 2 is mounted is rotatably mounted on a distal end surface of a cylindrical shield frame 1 and the face plate 3 is rotated to thereby rotate the cutter. In the excavation pit excavated by the cutter 2, a block made of concrete or the like called an arc segment 5 is assembled into a circular shape or the like by a segment assembling apparatus 4 provided inside the shield frame 1 so as to excavate the earth and sand in the shield frame 1. A tunnel 6 made of concrete is constructed, and a shield jack 7 provided inside the shield frame 1 is used to propel the shield frame 1 by supporting a reaction force at the tip of the existing portion of the tunnel 6. It was done.

Reference numeral 8 denotes a screw conveyor for transporting excavated earth and sand to the outside, and 9 denotes a driving force transmission mechanism 1.
0 is a motor for driving the face plate 3 to rotate.

[0005] Some shield excavators are provided with a stronger roller cutter 11 as the cutter 2 to excavate extremely hard ground such as rock.

The above roller cutter 11 is shown in FIGS.
As shown in FIG. 3, a shaft support 13 for supporting both ends of the shaft 12 is attached to the face plate 3, and the shaft 12 supported by the shaft support 13 is supported via a bearing 14 and a seal 15. A substantially cylindrical roller cutter body 16 is rotatably supported, and a cutter blade 1 is provided on the outer periphery of the roller cutter body 16.
7 is formed.

In FIG. 9, the cutter blade tip 17 is formed in a double state.
May be single or triple or more.

The roller cutter 11 obtains a high excavating ability with respect to a bedrock or the like by rotating the roller cutter body 16 and the cutter blade tip 17 around the shaft 12 with the rotation of the face plate 3. It becomes possible.

Conventionally, the cutter blade tip 17 of the roller cutter 11 is formed integrally with the roller cutter body 16 and hardened by quenching. However, the cutter blade tip 17 is hardened. Although hardening is not sufficient in terms of wear resistance, a ring-shaped cutter blade tip 17 made of hardened steel is now formed (not shown) so that the cutter blade tip 17 can be replaced. As shown in FIGS. 9 and 10, a carbide tip 18 having abrasion resistance 10 to 20 times higher than that of hardened steel is inserted into the top of the cutter tip 17 at a predetermined interval by press fitting or the like. Things that can be embedded to extend the life are being used.

It is also conceivable to form the ring-shaped cutter blade tip 17 with the same material as the cemented carbide tip 18 so that the cutter blade tip 17 can be replaced. However, the same material as the carbide tip 18 is hard. Since it is brittle, if it is formed in a ring shape, it will not be put to practical use, because even if it is cracked in one place, it may cause the whole to be damaged.

[0011]

However, the roller cutter 11 in which a plurality of carbide tips 18 are embedded at predetermined intervals at the top of the cutter blade tip 17 has the following problems.

That is, since the top of the cutter blade 17 directly hits the rock at the time of excavation, the wear of the top of the cutter blade 17 is greatly reduced by embedding the carbide tips 18 at a predetermined interval in this portion. However, as shown by the imaginary line in FIG. 11, the side portion of the cutter blade tip portion 17 holding the carbide tip 18 is worn out as shown by an imaginary line in FIG. Since the wall thickness is reduced, the holding force of the side of the cutter blade tip 17 is lost due to wear and thickness reduction, and the press-fitted carbide tip 18 may fall off.

In view of this, the hardfacing 19 is applied to the side of the cutter blade tip 17 to reduce the abrasion on the side of the cutter blade tip 17, but the hardfacing 19 still has a wear reducing effect. It was not enough.

The present invention has been made in view of the above circumstances, and has as its object to provide a roller cutter capable of preventing a carbide tip attached to a cutter blade from falling off.

[0015]

According to the present invention, there is provided a roller cutter characterized in that a cemented carbide tip 20 is fitted into a required number of notches 21 formed in a cutter blade tip portion 17 of a roller cutter body 16 and fixed by brazing. Such is the case.

In this case, the cutter blade tip 17
, A brazed carbide tip 20 and a press-fit type carbide tip 1
8 may be mounted together.

Alternatively, only the brazed carbide tip 20 may be attached to the cutter blade tip 17.

Further, a chip engaging portion 24 for mutually engaging between the notch 21 of the cutter blade tip portion 17 and the brazed carbide tip 20 may be formed.

According to the above means, the following effects can be obtained.

The cemented carbide tip 20 is fitted into a notch 21 formed in the cutter blade tip portion 17 of the roller cutter body 16, and the carbide tip 20 is brazed and fixed to the cutter blade tip portion 17. This makes it possible to produce the cutter blade tip portion 17 that does not have to be removed.

It is also possible to mount the brazed carbide tip 20 and the press-fit type carbide tip 18 together on the cutter blade tip 17.

Alternatively, it is also possible that only the brazed carbide tip 20 is attached to the cutter blade tip 17.

Further, by forming a chip engaging portion 24 which is mutually engaged between the notch 21 of the cutter blade tip portion 17 and the brazed carbide tip 20, the cutter blade tip portion 17 is formed.
It is possible to further increase the bonding force between the solder tip and the brazed carbide tip 20.

[0024]

Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1 to 3 show a first embodiment of the present invention.

Since the basic structure of the roller cutter is the same as that of FIGS. 8 to 11, the same parts are denoted by the same reference numerals and description thereof is omitted.

Numeral 19 is a hardfacing applied to the surface of the cutter blade portion 17.

In the present invention, the carbide tip 20 is attached to the top of the cutter tip 17 by brazing.

More specifically, a brazed carbide tip 20 is provided at a ratio of about one to several for a press-fit type carbide tip 18 attached to the top of the cutter blade tip 17.

In FIG. 1, the brazing carbide tips 20 are provided in a ratio of three for the three press-fitting carbide carbide tips 18, but the ratio of both is not limited to this.

The brazed carbide tip 20 is shown in FIG.
As shown in the figure, similar to the cross-sectional shape of the cutter blade tip portion 17, it is a pointed substantially triangular or pentagonal shape, and has a required thickness in the circumferential direction A of the roller cutter body 16. ing.

Then, a notch 21 slightly larger than the cemented carbide tip 20 is formed in the cutter blade tip portion 17, and the cemented carbide tip 20 is loosely fitted into the notch 21, and the bottom surface of the cemented carbide tip 20 and the aforementioned By pouring the molten brazing material 22 into the gap formed between the notch 21 and both end faces in the circumferential direction A,
The carbide tip 20 is integrally fixed to the cutter blade tip portion 17 and the roller cutter body 16.

The press-fit type cemented carbide tip 18 has a substantially cylindrical shape, and a cylindrical tip press-fit holding hole 2 which is slightly smaller than the press-fit type carbide tip 18 in the cutter blade tip 17.
3 and press-fitting cemented carbide 18 into the tip press-holding hole 23 while heating the periphery of the tip press-holding hole 23.
Is mounted by press fitting.

Next, the operation will be described.

The process of excavating the rock by the roller cutter is the same as that of FIG.

In the present invention, the rock directly contacting the rock at the time of excavation is the top of the cutter blade tip portion 17, and a press-fit type carbide tip 18 or a brazing carbide tip 20 is attached to this portion at a predetermined interval. Thus, the wear of the top of the cutter blade tip 17 can be greatly reduced.

When only the press-fit type carbide tip 18 is used, as described above, the side of the cutter blade tip 17 holding the carbide tip 18 is excavated without directly contacting the rock or the like. Since wear and thinning are caused by debris such as bedrock, the cutter blade tip portion 17 is worn and thinned.
Carbide tip 1 press-fitted due to lack of holding force by side
However, in the present invention, the cemented carbide tip 20 is integrally fixed to the cutter blade tip portion 17 and the roller cutter body 16 by the brazing material 22.
Even if all the press-fit type carbide tips 18 come off,
The brazed carbide tip 20 can be left, so that the brazing carbide tip 20 alone can maintain a certain level of excavation ability.

In addition, in addition to the above, the brazed carbide tip 20 has the effect of reducing the wear of the side of the cutter blade tip 17 and reducing / preventing the press-fit type carbide tip 18 from falling off. be able to.

That is, when the brazed carbide tip 20 is not embedded, the side of the cutter blade tip 17 is worn almost uniformly in the circumferential direction A of the roller cutter 11, whereas the carbide tip 20 is not worn. When brazing, the brazed carbide tip 20 has the same cross-sectional shape as the cutter blade tip portion 17 and the side surface extends to the side portion of the cutter blade tip portion 17. The wear of the portion can be suppressed.

Accordingly, when the side of the cutter blade tip 17 is viewed along the circumferential direction A of the roller cutter 11, the periphery of the brazed carbide tip 20 is partially worn and left. The holding force for the press-fit type carbide tip 18 close to the portion where the brazed carbide tip 20 is provided is left, so that the press-fit type carbide tip 18 can be prevented from falling off.

As described above, according to the present invention, the life of the roller cutter 11 can be extended.

FIG. 4 shows a second embodiment of the present invention, in which the side shapes of the brazed carbide tip 20 and the notch 21 (the shape of the roller cutter 11 as viewed from the axial direction) are such that the outer peripheral side has an upper bottom. And a trapezoidal shape having a lower bottom on the inner peripheral side and having a notch 21 of the cutter blade tip portion 17 and a chip engaging portion 24 for interlocking with each other between the brazed carbide tip 20. It is.

As described above, by forming the tip locking portion 24, it becomes possible to further increase the bonding force between the brazed carbide tip 20 and the cutter blade tip portion 17,
In addition, a structure that is stronger against lateral force and the like than when the chip engaging portion 24 is not formed can be provided.

Note that the shape of the chip engaging portion 24 is not limited to a trapezoidal shape.

Except for the above, the configuration is the same as that of the above embodiment, and the same operation and effect can be obtained.

FIGS. 5 and 6 show a third embodiment of the present invention, in which the carbide tips to be attached to the cutter blade portion 17 are all brazed carbide tips 20. FIG.

By doing so, it is possible to form the cutter blade tip portion 17 in which there is no fear of the carbide chip coming off.

In the brazing of the brazed carbide tip 20, since the heat input becomes larger than when the press-fit type carbide tip 18 is press-fitted, press-fitting is performed in order to avoid thermal distortion of the cutter blade tip 17. Since it is more difficult to mount the cemented carbide tip 18 as densely as the cemented carbide tip 18, as shown in FIG.
Instead of mounting the brazed carbide tip 20 mainly in places, the brazed carbide tip 20 is mainly inserted between the brazed carbide tips 20 and a press fit smaller than the press-fit type carbide tip 18. The small-sized carbide tip 25 may be appropriately mounted.

Except for the above, the present embodiment has the same configuration as that of the above-described embodiment, and the same operation and effect can be obtained.

FIG. 7 shows a fourth embodiment of the present invention. In the case of FIGS. 5 and 6, the side shapes of the brazed carbide tip 20 and the notch 21 (the roller cutter 11 is viewed from the axial direction). Notch 2 of the cutter blade tip 17 as a trapezoidal shape in which the outer side is the upper bottom and the inner side is the lower bottom.
A chip engaging portion 24 is formed between the brazing carbide tip 1 and the brazing carbide tip 20 so as to engage with each other.

As described above, by forming the tip locking portion 24, it becomes possible to further increase the bonding force between the brazed carbide tip 20 and the cutter blade tip portion 17,
In addition, a structure that is stronger against lateral force and the like than when the chip engaging portion 24 is not formed can be provided.

The shape of the chip engaging portion 24 is not limited to a trapezoidal shape.

Except for the above, the present embodiment has the same configuration as that of the above-described embodiment, and the same operation and effect can be obtained.

It should be noted that the present invention is not limited only to the above-described embodiments, and that combinations other than the above-described embodiments are also possible, and that other combinations are possible without departing from the spirit of the present invention. Of course, various changes can be made.

[0055]

As described above, according to the roller cutter of the present invention, an excellent effect of preventing the carbide tip attached to the cutter blade from falling off can be obtained.

[Brief description of the drawings]

FIG. 1 is a schematic side view of a first embodiment of the present invention.

FIG. 2 is a view taken in the direction of arrows II-II in FIG.

FIG. 3 is a view taken in the direction of arrows III-III in FIG. 1;

FIG. 4 is a partially enlarged side view showing a second embodiment of the present invention.

FIG. 5 is a partially enlarged side view showing a third embodiment of the present invention.

FIG. 6 is a view taken in the direction of arrows VI-VI in FIG. 5;

FIG. 7 is a partially enlarged side view showing a fourth embodiment of the present invention.

FIG. 8 is a schematic overall side sectional view of a shield machine for rock.

FIG. 9 is an enlarged sectional view of the roller cutter of FIG.

FIG. 10 is a side view of FIG. 9;

FIG. 9 is a view showing a state of wear of the side of the cutter blade tip;
FIG.

[Explanation of symbols]

 16 Roller cutter body 17 Cutter tip 18 Press-fit type carbide tip 20 Brazed carbide tip 21 Notch 24 Tip locking part

Claims (4)

[Claims] 1. A roller cutter characterized in that a cemented carbide tip (20) is fitted into a required number of notches (21) formed in a cutter blade tip (17) of a roller cutter body (16) and fixed by brazing. 2. The roller cutter according to claim 1, wherein a brazed carbide tip (20) and a press-fit type carbide tip (18) are mixedly mounted on the cutter blade tip (17). 3. The roller cutter according to claim 1, wherein only the brazing carbide tip (20) is attached to the cutter blade tip (17). 4. A notch (2) in a cutter blade tip (17).
4. A chip engaging portion (24) for mutually interlocking between 1) and a brazed carbide tip (20) is formed.
The roller cutter according to any one of the above.