JPH04176994A - Cutter for shield excavator - Google Patents

Abstract

PURPOSE:To easily replace bits by dividing spokes provided with the bits into a base section and a tip section, installing multiple lines of bits at the tip section, and coupling the tip section expandably and rotatably with respect to the base section. CONSTITUTION:Multiple spokes provided with cutter bits 9, 10a are divided into a base spoke 7 and a tip spoke 8, and they are coupled expandably and rotatably by a jack 15 and a motor 19. Multiple lines of bits 10a, 10b are installed on the surface of the tip spoke 8. When the bits 10a of the tip spoke 8 are to be replaced, the tip spoke 8 is rotated by the preset angle with the motor 19 and locked with a key and the like. The bits are easily replaced, and the efficiency can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a shield excavator that enables continuous excavation of tunnels over long distances by changing a cutter bit for excavation during excavation.

(Prior Art) A conventional shield excavator has a partition wall at the tip of a cylindrical shield plate, and the front side of the partition wall is used as an excavation chamber, and a rotary cutter that can move back and forth is housed in this chamber. The cutter is rotated to excavate the ground on the front side, and the excavated earth and sand is discharged by various devices such as a screw conveyor, and each time the excavated earth and sand are conveyed, the segments are assembled into a cylindrical shape at the rear end of the shield. I'm trying to cover it.

Such conventional shield excavators excavate earth and sand using a cutter bit protruding from the front of the cutter, and this cutter bit gradually wears out during excavation.
The digging capacity decreases and eventually it becomes impossible to dig. Therefore, the cutter bit needed to be replaced, but because the cutter was located in front of the bulkhead of the shield tube, it was impossible to replace it while excavating.

For this reason, in the past, it was necessary to install intermediate shafts at locations where the cutter bit needed to be replaced, and depending on the performance of the cutter bit and the soil quality of the ground to be excavated, - a large number of shafts were required in the construction area. The cost of building it is large,
There was also speculation that the construction period would be longer.

In an attempt to solve this problem, a cutter spoke is rotatably supported around its longitudinal axis, and cutter bits are arranged in multiple rows along the longitudinal direction around the cutter spoke. A shield excavator has been proposed in which the excavation cutter bits are changed by protruding from the cutter spokes and rotating the cutter spokes so that a new row of cutter bits faces the front side (Utility Model No. 63-165395 Publication No.).

(Problem to be Solved by the Invention) The device for rotating the cutter spoke in order to change the conventional excavation cutter bit described above rotates the entire cutter spoke, so it is not necessary to install it on a disc-shaped cutter plate. However, it is possible to implement the cutter with a structure in which the cutter spokes are supported in the slit, but it is possible to implement the cutter with a structure in which the cutter spokes are protruded radially in a cantilevered manner around the rotation center body fixed to the excavation rotation drive shaft. In such cases, there is a problem in that it is nearly impossible to support the cutter spokes in a rotatable manner relative to the center body due to strength considerations.

In addition, the wear rate of the cutter bit generally decreases the closer it is to the center of drilling rotation, and increases as it approaches the outer periphery.
Although it has been found that the difference in wear between the two is extremely large,
In the conventional cutter described above, the entire cutter spoke is rotated to change all the excavating cutter bits, which means that even the ones with the least degree of wear have to be changed, which is uneconomical.

In consideration of these problems, the present invention provides sufficient strength even with a cutter structure in which the cutter spokes are cantilevered and protrudes radially from the center body, and moreover, the cutter can be used for excavating the most necessary parts. The purpose of this invention is to provide a cutter for a shield excavator that allows the bit to be changed.

(Means for Achieving Problem S) A feature of the present invention for achieving the above-mentioned object is that the shield tube is provided on the front side of the partition wall at the tip of the shield cylinder and radially extends around the outer periphery of the cutter center body supported by the rotary drive shaft. A cutter for a shield excavator, which has a plurality of cutter spokes protruding from the cutter spokes and a cutter bit protruding from each of the cutter spokes, the cutter spokes comprising a cylindrical base spoke integrally protruding from the center body of the cutter; , and a tip spoke that is supported within the base spoke and protrudes in the distal extension direction thereof, and a cutter bit is provided protruding from the front side of the base spoke, and the tip spoke is supported within the base spoke in its longitudinal direction. drive means for rotatably supported around an axis thereof, having cutter bits protrudingly arranged in a plurality of rows around the shaft, and rotating the tip spoke between the tip spoke and the base spoke; and the plurality of rows of cutter bits. The main feature of the invention is that it is provided with adjustment means for non-rotatably locking each row in a position facing the front side.

(Function) This cutter for shield excavator is used during excavation.
The cutting rotation of the cutter is stopped, the adjusting means is operated to make the tip spoke rotatable, and the driving device is used to rotate the tip spoke by a certain angle so that the unused cutter bit in the next row faces the front side. After that,
The adjusting means returns the cutter bit to a non-rotatable state, thereby changing only the tip spoke portion of the cutter bit.

(Example) Next, an example of implementation of the present invention will be described with reference to the drawings.

In the figure, 1 is a shield cylinder, and 2 is a partition provided at the front end of the shield cylinder 1. A bearing 3 is fixed to the central portion of the partition wall 2, and a force lever shaft 4 is rotatably supported on this bearing so as to be movable in and out of the shaft. A cutter center body 5 is fixed to the tip of the cutter shaft 4, and six cutter spokes 6,6, .

Each cutter spoke 6 has a cylindrical base spoke 7 that integrally projects from the center body 5, and a tip spoke 8 that is supported by the base spoke 7 and is arranged in the extending direction.
It is composed of.

Cutter bits 9 are protruded from the front surface of the base spoke 7 in a row. A cutter bit 1 is attached to the tip spoke 8 on its front surface and on the rear surface that is swiveled by 180 degrees.
0a and 10b are protruded in two rows.

The distal spoke 8 is rotatably fitted into the proximal spoke 7 on its proximal end side and movable in and out in the axial direction, and an adjusting means 11 and a rotation driving means 12 are provided between the two.

The adjusting means 11 includes a locking key 13 protruding in four directions on the outer periphery of the distal end spoke 8 and a proximal spoke 7.
four key grooves 14. provided on the inner surface of the key 13 into which the keys 13 fit. and a spoke telescopic jack 15 using a hydraulic cylinder that moves the tip spoke 8 in and out in the axial direction.
It is composed of. The cutter center body 5 side of each key groove 14 is continuous with the annular groove 16, and each of the keys 13 can move within this annular groove 16 in the circumferential direction.

The rotation drive means 12 is a gear 17 formed on the base end surface of the tip spoke 8. It consists of a gear transmission mechanism 18 and a drive motor 19 that mesh with this, and the tip spoke 8 is moved in the retracting direction by a jack 15, and each key 13 is moved into a key groove 1.
4 and is in the annular groove 16, the teeth on the lower end surface! 17 is meshed with a gear mechanism 18, and in this meshed state, the drive motor 19 is rotated by an amount that rotates the tip spoke 8 by 180 degrees.

In the figure, 20 is a copy cutter, and 21 is a hydraulic jack for moving the copy cutter in and out.

The cutter having an oval shape as described above excavates by stretching the shirt 815, pushing out the tip spoke 8, and rotating the cutter shaft 4 in a state in which it is not rotatable by being fitted into each key 13 or keyway 14.

At the point when the planned distance has been dug, the jackpot is 15
The key 13 is pulled out from the key groove 14 into the annular groove 16 by operating the tip spoke 8 and pulling out the key 13 from the key groove 14 into the annular groove 16.
7 is meshed with the gear transmission mechanism 18. After that, the drive motor 19 is rotated to rotate the tip spoke 8 by 180 degrees.

As a result, the worn cutter bit 10a on the front side moves to the rear side, and the unused cutter bit 10b on the rear side simultaneously moves to the front side.
changes will be made.

In addition to the above-mentioned adjustment means and rotational drive, various mechanisms can be used, and the cutter bit rows of the tip spokes are two rows separated by 180°, three rows separated by 120°, and three rows separated by 90°.
Other multiple columns can be used, such as four columns of each.

(Effects of the Invention) As described above, the cutter for a shield tunneling machine of the present invention includes a cylindrical base spoke in which the cutter spoke integrally projects from the center body, and a tip end rotatably supported within the base spoke. The spokes are oval shaped, and the tip spoke can be rotated to change the excavation cutter bit on the front side to an unused cutter bit on the rear side, allowing the cutter spoke to protrude radially in a cantilevered manner. Even with a cutter of this type, the rotating tip spoke is strongly supported, making it realistic to change the cutter bit by rotating the cutter spoke, and also making it possible to change the cutter bit of the entire cutter spoke. Instead, only the tip part is changed, so it is more economical.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, and FIG. 1 is a front view;
Fig. 2 is a longitudinal sectional view of the same, Fig. 3 is a sectional view taken along line A-A in Fig. 2, Fig. 4 is a sectional view taken along line B-B of Fig. 2, and Fig. 5 is a cross-sectional view showing the retracted state of the tip cutter. It is a diagram. 1...Shield simple, 2...Bulkhead, 3.
... Bearing, 4 ... Cutter shaft, 5 ...
... Cutter center body, 6 ... Cutter spoke, 7 ... Base spoke, 8 ... Tip spoke, 9.10a, 10b, ... Cutter bit, 1
DESCRIPTION OF SYMBOLS 1... Adjustment means, 12... Rotation drive means, 13... Key, 14... Keyway, 15... Spoke telescopic jack , 16...
...Annular groove, 17...Gear, 18...
Gear transmission mechanism, 19... Drive motor.

Claims (1)

[Claims] A shield in which a plurality of cutter spokes protrude radially from the outer periphery of a cutter center body supported by a rotary drive shaft, located on the front side of the bulkhead at the tip of the shield cylinder, and a cutter bit is protruded from each cutter spoke. In the cutter for an excavator, the cutter spoke includes a cylindrical base spoke integrally protruding from the cutter center body, and a tip spoke supported within the base spoke and protruding in an extension direction on the distal end side thereof. A cutter bit is provided protruding from the front side of the base spoke, the tip spoke is rotatably supported within the base spoke about its longitudinal axis, and cutter bits are protruded in multiple rows around the tip spoke. and a driving means for rotating the tip spoke between the tip spoke and the base spoke, and an adjusting device for locking each row of the plurality of rows of cutter bits in a position facing the front side so as not to rotate. A cutter for shield tunneling machines.