JP3089858B2 - Roller bit wear detector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for detecting wear of a roller bit provided on a cutter head of a tunnel excavator.

[0002]

2. Description of the Related Art A shield machine mainly comprises a cylindrical shield frame, a cutter head rotatably provided at a front portion of the shield frame, and a cutter chamber provided at a rear portion of the cutter head. The ground is excavated by rotating the cutter head, the excavated earth and sand is taken into the cutter room, and is discharged into the tunnel via a screw conveyor or a mud pipe, etc. It digs inside.

[0003] A shield excavator or a tunnel excavator for excavating soft rock or boulders is provided with a plurality of roller bits which are formed on the front face of the cutter head and project to the face side to form substantial excavated teeth. ing. These roller bits have a rotation axis in the radial direction of the cutter head. As the cutter head rotates, it bites into the face (soft rock) and rolls in the circumferential direction on the face, excavating the ground. Is what you do.

[0004]

When excavating a soft rock mass over a long distance, the above-mentioned roller bit must be replaced because the roller bit is worn and the excavating ability is reduced. However, since the roller bit is provided on the front side of the cutter head facing the face side,
It was not easy to detect the state of wear from the inside of the fuselage, and it was not possible to accurately determine the time to replace the roller bit.

[0005] In particular, in a roller bit of a type in which cemented carbide tips are cast at predetermined intervals on the outer peripheral portion, the gap between the soft cemented carbide chips is worn in a concave shape, and the hard cemented carbide tip portion remains in a convex shape. It will be worn in a shape. In this case, the measurement result greatly differs depending on whether the wear amount is measured at the top of the cemented carbide tip or between the tips.

SUMMARY OF THE INVENTION An object of the present invention, which has been made in view of the above circumstances, is to provide a roller bit wear detecting device capable of accurately detecting a roller bit wear state.

[0007]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention relates to a tunnel excavator in which a cutter head is provided with a roller bit having a rotating shaft in a radial direction facing a face side so as to be rotatable. In the inside of the cutter head, mini-jacks are provided so as to be able to protrude and retract from the cutting edge of the roller bit on the opposite side to the cutting face so as to come into contact with the cutting edge, and an endoscope for observing the projecting amount of these mini-jacks is provided. It is configured.

[0008]

When the wear of the roller bit is detected, the mini jacks provided in the cutter head are protruded, and their tips are brought into contact with the cutting edge of the roller bit. In this state, the wear state of the roller bit can be detected by observing the amount of protrusion of each mini jack with the endoscope.

By detecting the state of wear in this way, a plurality of mini jacks can be arranged for one pitch even for a roller bit of a type in which a cemented carbide tip is cast on the outer peripheral portion at a predetermined interval. By protruding and abutting these, it is possible to accurately detect the wear state of the outer peripheral portion of the roller bit that is worn in an uneven manner.

[0010]

An embodiment of the present invention will be described with reference to the accompanying drawings.

FIG. 1 is a partial sectional side view of a cutter head 1 of a shield excavator for soft rock. The cutter head 1 is rotatably provided at the front of a cylindrical shield frame (not shown), and is rotatably driven by a cutter motor. As shown in the figure, a front portion 3 facing the face 2 of the cutter head 1 is formed in an arc shape, and a roller bit 5 is attached thereto via a bracket 4.
Are provided rotatably. The roller bit 5 is integrally formed in a shape in which a cylindrical portion 5a and a disk portion 5b are coaxially overlapped, and a blade portion 6 for excavating the face 2 is formed on an outer peripheral portion of the disk portion 5b. Carbide tips 7 are cast in the blade portion 6 at predetermined intervals along the outer periphery as shown in FIG. The roller bit 5 has a rotating shaft 8 arranged along the radial direction of the cutter head 1, and with the rotation of the cutter head 1, the blade portion 6 of the disk portion 5 b moves to the cutting face 2 (soft rock) as the cutter head 1 rotates. It bites and rolls on the face 2 in the circumferential direction.

Inside the cutter head 1, there are provided three mini jacks 9 which are opposed to the blade portion 6 of the roller bit 5 on the side opposite to the face 2 and which come into contact with the blade edge so as to be able to protrude and retract. These mini jacks 9, as shown in FIG.
Three pieces are provided for one mounting pitch of the carbide tips 7. The mini jacks 9 are housed in a common casing 10 so as to be able to protrude and retract, and have a flange 11 at an end opposite to the roller bit 5. A spring 12 accommodated in the casing 10 is in contact with the upper surface of the flange 11, and the mini jack 9 is urged by the spring 12 in the retraction direction (downward in the drawing). The casing 10 is provided with a pressure oil inlet 13 for supplying oil pressure to the inside. When oil pressure is supplied from the pressure oil inlet 13 to the inside of the casing 10, each mini jack 9 is moved to the roller bit 5 side. It is designed to protrude. The end of the mini jack 9 on the roller bit 5 side is formed in a stepped shape having a diameter reduced in multiple steps. The step portion 14 functions as a three-dimensional scale that makes it easy to read the amount of protrusion of the mini jack 9 by an endoscope 15 described later.

As shown in FIG. 1, the endoscope 15 is provided inside the cutter head 1 via a bracket 16 so as to face the gap between the mini jack 9 and the roller bit blade 6. The endoscope 15 is provided on the inner diameter side of the cutter head 1 perpendicular to the roller bit disk portion 5b. As shown in FIG. 3, the endoscope 15 mainly includes a storage tube 17 in which a viewing unit 18 is housed. A tempered glass 19 for protecting the examination section 18 is attached to a front portion of the storage tube 17 by a glass presser 20, and the entire endoscope 15 has a water pressure resistant structure. The inside of the storage tube 17 is filled with a desiccant 21 to prevent the inner surface of the tempered glass 19 from fogging. A space heater (not shown) may be provided instead of the desiccant 21 to prevent the tempered glass 19 from fogging. The cable 22 of the endoscope 18 is connected to the center rotary joint (not shown) of the cutter head 1 from the storage tube 17.
Up to a protective tube 23 having an external water pressure resistance. In the figure, reference numeral 24 denotes an impact material for protecting the inspection unit 18 from vibration;
25 is a partition plate, 26 is a silicon filler.

The front surface of the tempered glass 19 of the endoscope 15 is covered with a sliding plate 27 as shown in FIG. 1 so that the tempered glass 19 is protected from being scratched due to excavation slips. ing. The sliding plate 27 is connected via a bracket 30 to a single-acting jack 29 which is pulled in by a spring 28 and pushed out by hydraulic pressure as shown in FIG. According to this configuration, the sliding plate 27 normally covers the tempered glass 19 because the single-acting jack 29 is immersed by the urging force of the spring 28, and when the hydraulic pressure is supplied from the oil supply hole 31, the single-acting jack 29 is moved. Since the endoscope 15 is extended and protruded, the endoscope 15 moves out of the field of view. In the figure, 3
2 is a guide rod for guiding the movement of the bracket 30.

As shown in FIG. 1, a water jet nozzle 33 for cleaning the surface of the tempered glass 19 is provided at a position of the endoscope 15 facing the tempered glass 19. The water injection nozzle 33 is provided on the outer peripheral side of the cutter head 1 with the bracket 3.
4 and is arranged coaxially with the endoscope 15.

The operation of this embodiment having the above configuration will be described.

When the wear of the blade 6 of the roller bit 5 is detected, first, the rotation of the cutter head 1 is stopped. next,
Hydraulic pressure is supplied to the single-acting jack 29 to move the sliding plate 27 from the front surface of the tempered glass 19 of the endoscope 15 to outside the field of view. Then, water is sprayed from the water spray nozzle 33 toward the front surface of the tempered glass 19 to clean the surface of the tempered glass 19. Thereafter, the three mini jacks 9 provided in the cutter head 1 are made to protrude, and their tips are brought into contact with the blade portions 6 of the roller bits 5.

In this state, the projection amount of each mini jack 9 is observed by the endoscope 15 through the cleaned tempered glass 19. At this time, since the step portion 14 is provided at the tip of the mini jack 9, the protruding state of each jack 9 can be easily observed. Further, in order to further facilitate observation, a light illuminating the front may be provided inside the storage tube 17.
Thereby, the endoscope 15 can visually read the increase in the gap due to the wear of the roller bit 5 as the increase in the amount of movement of the mini jack 9 with respect to the initial gap between the roller bit 5 and the mini jack 9.

By detecting the wear state of the roller bit 5 as described above, even the roller bit 5 of the type in which the carbide tips 7 are cast at a predetermined interval on the outer peripheral portion as shown in FIG. By protruding and abutting the three mini jacks 9 on the minute, it is possible to accurately detect the abrasion state of the outer peripheral portion (the blade portion 6) of the roller bit 5 that is worn in an uneven manner.

[0020]

As described above, according to the present invention, the wear state of the roller bit can be accurately and remotely detected as an image, so that the life and the replacement time of the roller bit can be safely and accurately determined.

[Brief description of the drawings]

FIG. 1 is an explanatory view of a roller bit wear detecting device according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line II-II of FIG.

FIG. 3 is a sectional view of an endoscope constituting the wear detecting device.

FIG. 4 is an explanatory diagram of a sliding plate provided on a front surface of the endoscope.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cutter head 2 Face 5 Roller bit 6 Blade part as a cutting edge 9 Mini jack 8 Rotation axis 15 Endoscope

Claims (1)

(57) [Claims] 1. A tunnel excavator in which a roller bit having a rotation axis in a radial direction thereof faces a face of a cutter head and is rotatably provided on the cutter head. A wear detecting device for a roller bit, wherein a mini jack is provided so as to be able to protrude and retract so as to be opposed to the cutting edge and abut on the cutting edge, and an endoscope is provided for observing the projecting amount of the mini jack.