JPH0144880B2 - - Google Patents

Description

[Detailed description of the invention] Industrial applications The present invention relates to a small diameter shield tunneling machine.

Configuration of conventional examples and their problems Some small-diameter shield excavators have a screw-type earth removal device. Conventionally, this type of shield excavator has been provided with a screw-type earth removal device consisting of a cylindrical casing and a screw blade in the shield main body, and a cutter head connected to the front end of the rotating shaft of the screw blade for rotation. It was the one I made. According to this, there were cases in which large-diameter gravel mixed in the ground could not be crushed by the cutter head alone.

OBJECTS OF THE INVENTION It is an object of the present invention to provide a small-diameter shield tunneling machine that can eliminate the above-mentioned conventional drawbacks.

Structure of the Invention In order to achieve the above object, the small-diameter shield excavator of the present invention is provided with a screw type earth removal device consisting of a cylindrical casing and a screw blade in the shield main body, and a cutter head is attached to the screw blade. In a small-diameter shield excavator connected to the front end of the rotating shaft, the front end of the cylindrical casing is made to protrude forward from the front end of the shield main body and has approximately the same outer diameter as the shield main body, and the front end of the cylindrical casing is provided with a dovetail-shaped An excavated soil guiding recess is formed, the front end of the rotary shaft corresponding to the guiding recess is formed into a conical part that widens as it goes forward, and a cutter bit is provided on each surface of the guiding recess and the conical part, and the cylindrical casing is The cutter head is provided with a rotary drive device for rotating the screw blade, and a telescoping jack for moving the rotation shaft of the screw blade in the axial direction to move the cutter head in and out.

Embodiment and Operation An embodiment of the present invention will be described below with reference to FIGS. 1 to 5. In FIGS. 4 and 5, reference numeral 1 denotes a small-diameter shield main body, in which a screw-type earth removal device 2 is disposed. This screw-type earth removal device 12 is composed of a cylindrical casing 3 and a screw blade 5 rotatably disposed within the cylindrical casing 3 and rotated via a rotating shaft 4. The cylindrical casing 3 is supported within the shield body 1 via a swing bearing 6, and is operatively connected to a first rotational drive device (described later) to be rotated. The front end of the cylindrical casing 3 protrudes forward from the front end of the shield body 1 and has approximately the same outer diameter as the shield body 1, and is provided with a mortar-shaped excavated earth guiding recess that opens at the front. 3a is formed, and a large number of cutter bits 7 are attached to the surface of this guide recess 3a. Further, half of the outer circumferential surface of the front end of the cylindrical casing 3 is formed into an inclined surface 3b that is inclined toward the 1-axis axis of the shield body (gradient a at the intermediate portion is 1/10). The front end of the rotating shaft 4 of the screw blade 5 is formed into a conical part 4a that widens toward the front end, and a number of cutters 8 are attached to the surface of this conical part 4a. Note that the surface of this conical portion 4a is sloped to be slightly gentler than the slope of the surface of the guide recess 3a of the cylindrical casing 1, so that the entrance of the excavated earth and sand intake space A is wide and goes deep. The screw blade 5 is made to gradually become narrower as the conical portion 4a increases.
It has been extended to A cross-shaped cutter head 9 is attached to the front end of the rotating shaft 4.
The rear end is operatively connected to a second rotary drive device (not shown) and to a telescopic jack (described later), so that the rotating shaft 4, that is, the cutter head 9 is located between the solid line position and the imaginary line position in Figure 4. You can come and go as you please.

Next, the driving portion will be explained based on FIGS. 1 to 3. Note that the drawing shows a state in which the shield main body is connected to the drive device 11 via the hump tube 10 and is placed on the starting frame 12. Of course, the screw-type earth removal device 2 is also connected to the drive device 11 via the cylindrical refilling casing 3' and the screw blades 5'. The drive device 11
The slide body 14 is slid on the starting frame 12 in the front-rear direction via the propulsion jack 13, the first rotary drive device (for example, a geared motor) 15 that rotates the cylindrical casing 3, the screw blade 5 and the cutter head 9. a second rotary drive device (for example, a geared motor) 16 that rotates the cutter head 9; and a pair of rotary drive devices that are interposed between the slide body 14 and the support base 17 of the second rotary drive device 16 and move the rotary shaft 4, that is, the cutter head 9, in and out. The telescopic jack 18, the slide body 14, and the support base 1 of the first rotary drive device 15
9 and a telescopic jack 20 for adjusting the gap between the connecting portion and the first rotary drive device 15 when adding the cylindrical casing 3. Reference numeral 21 denotes a pair of support rollers provided at the front of the starting frame 12 for supporting the shield main body side. 22 is a dirt receiving tank provided within the starting frame 12. In addition, in FIG. 4, 23 is a light emitting diode provided in the hollow hole 4b of the rotating shaft 4, and is for detecting the traveling direction of the shield body 1.

Next, the operation will be explained.

During normal excavation, the cutter head 9 is attached to the cylindrical casing 3 as shown by the solid line in Figure 4.
Excavation is performed by rotating the cutter head 9 and the screw blade 5 while keeping the cutter head 9 close to the side. If coarse gravel is mixed in the ground, the cutter head 9 is moved in and out using the telescopic jack 18, and the cylindrical casing 3 is rotated to remove coarse gravel between the guide recess 3a and the conical part 4a. Crush the gravel. In addition, if coarse gravel enters the guide space A, only the cylindrical casing 3 may be rotated to crush it. Of course, the rotation direction of the cylindrical casing 3 can be selected in either direction. The crushed gravel is then discharged backward by the screw blade 5. Next, when correcting the direction of the shield body 1, the inclined surface 3b on the outer periphery of the front end of the cylindrical casing 3
If you move it to the opposite side of the direction you want to correct it, and excavate while rocking and rotating it left and right within a small angle range, the reaction force from the ground acting on this slope 3b will The shield body 1 is bent in the desired direction. In addition, during normal excavation, since it rotates 360 degrees, the reaction force from the ground acts evenly on the entire circumference, so it does not bend.

Effects of the Invention According to the configuration of the present invention, the cutter bit is provided in the guide recess at the front end of the cylindrical casing and the conical part at the front end of the rotating shaft, and the cylindrical casing is also rotated. Even gravel can be crushed between the guide recess and the conical part. In addition, if coarse gravel is mixed in the ground, the coarse gravel can be crushed between the guide recess and the conical part by moving the cutter head in and out using the telescopic jack and rotating the cylindrical casing. can.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention; FIG. 1 is an overall side view, FIG. 2 is a plan view of the same, FIG. 3 is a front view of the same, FIG. 4 is an enlarged sectional view of main parts, and FIG. is a view taken along the - arrow in FIG. DESCRIPTION OF SYMBOLS 1...Shield main body, 2...Screw-type soil removal device, 3, 3'...Tubular casing, 3a...Guiding recess, 3b...Slanted surface, 4...Rotating shaft, 4a...
...Conical part, 4b...Hollow hole, 5,5'...Screw blade, 7,8...Katsutabitsu, 9...Katsuta head, 12...Start mount, 14...Slide body, 15...First rotation Drive device, 16...second
Rotary drive device, 18, 20... telescopic jack.

Claims (1)

[Claims] 1. In a small-diameter shield excavator in which a screw-type earth removal device consisting of a cylindrical casing and a screw blade is provided in the shield main body, and a cutter head is connected to the front end of the rotating shaft of the screw blade, the front end of the cylindrical casing The front end of the cylindrical casing is made to protrude forward from the front end of the shield body and has approximately the same outer diameter as the shield body, and a mortar-shaped excavated soil guide recess is formed in the front end of the cylindrical casing, and the front end of the rotating shaft corresponding to the guide recess is formed. A conical part is formed that widens toward the front, and a cutter bit is provided on each surface of the guide recess and the conical part, and a rotary drive device for rotating the cylindrical casing and a rotating shaft of the screw blade are moved in the axial direction. A small-diameter shield excavator characterized by being equipped with a telescopic jack for moving the cutter head in and out.