JPS63165692A - Shield excavator - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a shield excavator that can excavate a tunnel by changing the direction of excavation, and in particular, the shield excavation machine can easily change the direction of excavation to the left, right, and up and down directions. Regarding structure.

[Prior Art] Changing the direction of tunnel excavation by bending the linear shape of a tunnel in a shield tunneling machine is necessary when constructing curved shields and correcting meandering, and has been done in the past.

Even when the direction of change is mainly in the direction of tunnel excavation, it occurs less frequently than in the left-right direction. In addition to the above-mentioned ground conditions, the vertical change in direction is due to the fact that the entire center of gravity of the shield excavator is located at a position approximately tenths of the full length from the front end surface due to the fact that most of the main equipment is located at the front.
Since the front part of the shield tunneling machine tends to always turn downward due to its own weight, so-called nose-down, the frequency at which the shield tunneling machine corrects its direction upward, except in hard ground that will not sink under its own weight, is There are quite a few.

For this reason, it is desirable to be able to change the direction of excavation in the horizontal and vertical directions, and this is particularly necessary depending on the conditions of the ground. However, if the left-right direction and the up-down direction are changed at one time, for example, if the left-right direction is 3 degrees, then the up-down direction is approximately 0.1-0.2 degrees, which is quite small compared to the left-right direction. It's fine. This is due to the fact that the change in left and right direction is unavoidable at road intersections, etc., and has an extremely small radius (
For example, in a 50mR) curve, we often encounter cases where we are forced to make a 90° turn, whereas in the vertical direction, the tunnel line does not bend at a sharp angle like in the left/right direction, and the tunnel line can be bent by at most 1°. This is because the direction change is ~2'', and the number of times the direction change is usually much smaller than in the left-right direction, as is the angle.

Conventional shield tunneling machines that can excavate tunnels by changing the direction of excavation are those that can change the direction of excavation only in one direction, left or right or up and down (Japanese Patent Application No. 14888, Utility Application No. 55-
132,530), and those that are possible in the horizontal and vertical directions, as well as those that are possible in all directions by selecting and combining the horizontal and vertical angles (Japanese Patent Application No. 14887-1987). However, the above-mentioned device that can only be turned in one direction has the disadvantage that priority is given to changing direction in the left-right direction due to the above-mentioned reason, and as a result, it is impossible to change direction in the vertical direction. In the system shown in Fig. 1, a ring girder with a box-shaped cross section is provided between the front and rear divided shields, and the front shield and rear shield are connected by pins so as to be able to swing left and right or up and down through the ring girder. , a mechanical fixing device is provided between the front shield and the rear shield to fix the movement of both when the shield excavator moves straight and when the direction change operation is completed, and the said fixing device is installed before and after the direction change operation. The work of releasing and fixing the device involves the work of releasing and fixing, and the work of releasing and fixing requires selecting the fixing device according to the direction of change. Also, the ring girder is required due to the structure, so it is not possible to directly move the device forward. This has problems in that the overall length of the shield is longer than in one in which the front shield and the rear shield are connected, and the structure including the connecting part is complicated. On the other hand, there is a model that can change the direction of excavation in all directions, in which the front shield and the rear shield are connected by a number of hydraulic jacks. Internal leaks are likely to occur in the hydraulic jack and the equipment in its hydraulic circuit, making it impossible to maintain a predetermined turning attitude and making direction control difficult, which complicates the operation of the shield excavator. It had a point.

[Problems to be Solved by the Invention] As mentioned above, in conventional shield tunneling machines, the structure for changing the direction of excavation 4 in one direction is capable of changing the direction in the left and right direction but not in the vertical direction, or in some cases it is possible to change the direction in all directions. However, before and after changing direction, it is necessary to release and fix the fixing device between the front and rear shields, and a ring guard is required to connect the front and rear shields, making the structure complicated. All of them had problems in that they could not be easily changed in left-right and up-down directions, such as being unable to maintain a predetermined turning posture and making directional control difficult.

The present invention solves the problems of the prior art described above, and aims to provide a shield excavator that has a simple configuration and can easily and reliably change the direction of excavation.

[Means for Solving the Problems] The present invention provides a shield excavator including a cylindrical shield main body and a cylindrical tail shield connected to the rear part of the shield main body via a connecting means. a first connecting means for connecting the rear part and the front part of the tail shield opposite thereto in such a manner that one of the upper part and the lower part thereof can be relatively bent left and right and up and down; - a second connecting means that connects in a relatively expandable manner;
One end is connected to the shield main body side and the other end is connected to the tail shield side, and by expansion and contraction, the shield main body and the tail shield are connected to the left and right side via the first connecting means and the second connecting means.
By providing at least two bending jacks that bend up and down, the direction of tunnel excavation can be easily determined.
This allows for easy and reliable change of direction.

[Function] At the divided part of the shield, one
The first and second connecting means provided in pairs are connected to each other by vertical pins, and when a tunnel is excavated straight, both the upper and lower connecting means are connected through the pins of the connecting means. The digging force caused by the shield jack is transmitted equally from the shield body to the tail shield. In this case, the hydraulic jack for bending is placed in a locked state by stopping the flow of pressure oil to maintain the straight-ahead posture. Next, when the tunnel is bent upward or downward in order to bend the linear shape of the tunnel, the second connecting means is shortened by the hydraulic jack for bending with respect to the excavation direction. The pin part is used as a swinging fulcrum to relatively shorten the two parts.

This relative shortening connects the second connecting means on the side to be relatively shortened (e.g. the upper part) in such a way that it can expand and contract in a length dimension corresponding to the maximum deflection angle required during the tunnel line. However, the first connecting means on the side (for example, the lower part) that becomes the swinging fulcrum is achieved by setting the diameter of the pin hole to a size that has a gap that allows the above-mentioned expansion and contraction. When a predetermined deflection angle is reached due to the relative shortening, the hydraulic jack for steering is put into the locked state and digging work is performed using the shield jack. In order to return the vehicle to a straight-ahead state, the bending hydraulic jack can be operated in the opposite direction. On the other hand, when turning in the left-right direction, by extending or shortening the hydraulic jack for bending, the front side of the divided shield is rotated by the pins of both the upper and lower connecting means. Let your mind swing around it. When a predetermined turning angle is reached in either the left or right direction, or when returning from the turning state to the straight traveling state, the same operation as in the case of the up-down direction is performed.

[Example] An example of the present invention will be described with reference to FIG. 1 and FIG. 6. Figure 1 is a side cross-sectional view of the shield tunneling machine divided into two parts, front and rear, Figure 2 is a cross-sectional view taken along nn in Figure 1, Figure 3 is a cross-sectional view taken along ■-■ in Figure 1, and Figure 4 is FIG. 3 is an enlarged cross-sectional view taken along the line IV-IV in FIG. 3, FIG. 5 is an explanatory diagram of the operation when the linear shape of the tunnel is bent upward, and FIG. 6 is an explanatory diagram of the operation of the connecting portion. In the figure, 1 is the front side of the divided shield (hereinafter referred to as the shield body), and 2 is the rear side (hereinafter referred to as the tail shield), both of which have approximately the same diameter and are formed into a highly rigid cylindrical shape. ing. There is a ring-shaped rib 1a on the inner circumference of the rear part of the shield body 1 (tail shield 2 side).
A ring-shaped rib 2a is similarly fixed to the inner periphery of the front portion of the tail shield 2 (on the side of the shield main body 1). The front part of the seal 2 has an extending cylindrical part 2b whose outer diameter is slightly smaller than the inner diameter of the shield body 1, and a gap is provided at the rear of the shield body 1 so that it can swing in the radial direction. It has been inlaid. At the upper and lower parts of the cylindrical part 2b,
A bracket 2c for connecting the shield body 1 and the tail shield 2 with a pin is provided so as to protrude from the rib 2a with a gap 3 between the inner circumference of the cylindrical portion 2b and the length substantially matching the tip of the cylindrical portion 2b. ing. A plate-shaped bracket 1b having an oblong hole 4 projecting from the side surface of the rib 1a is fitted into the gap 3 between the upper and lower parts, and a plate-shaped bracket 1c having a circular hole 5 is fitted into the lower side. and bracket lb.

A pin 6 inserted through the cylindrical portion 2b and the bracket 2c is inserted into the holes 4 and 5 provided in both of the pins 1c, thereby connecting the shield body 1 and the tail shield 2. in this case,
The oblong hole 49 and the circular hole 5 are arranged so that the axes of the upper and lower pins 6 are on the same vertical line. In addition, the oval hole 4 is an oval of a length that allows the maximum deflection angle θmax in the vertical direction per time when the tunnel line core is bored, that is, approximately (
The outer diameter of the shield body 1 is set to DX tan θmax), while the circular hole 5 is a hole having a sufficient gap between it and the pin 6 to allow the above-mentioned angle θmax. Specifically, this gap is approximately between the outer diameter of the shield body 1 and the bracket 1c.
The dimension is determined by the ratio to the thickness dimension of. In this embodiment, the lower connecting means is the first connecting means, and the upper connecting means is the second connecting means. Reference numeral 7 denotes hydraulic jacks for bending, which are provided on the left and right sides of the divided portion of the shield, that is, at positions orthogonal to the connecting portion, and in the case of this embodiment, the end on the cylinder side is fixed to the inner circumference of the shield body 1. Both are swingably attached via spherical bearings to a bracket whose end on the piston rond side is fixed to the inner periphery of the rib 2a and the cylindrical portion 2b.

Reference numeral 8 designates hydraulic jacks for bending that are provided close to the second connecting means side and on the left and right sides of the second connecting means, and both ends of each hydraulic jack 8 are swingably attached in the same way as the hydraulic jacks 7. ing. Extend one side of the hydraulic jack 7,
If you shorten the other.

The shield main body 1 swings its head toward the shortened jack 7 with respect to the tail shield 2 about the pin 6 as an axis. Further, when both hydraulic jacks 8 are shortened, the shield body 1 is swung upward with respect to the tail shield 2 using the hole 5 of the bracket 1c as a fulcrum until one end of the oblong hole 4 of the bracket 1b abuts the pin 6. It will be done. When the hydraulic jack 8 is almost fully extended, the other end of the oblong hole 4 is in contact with the pin 6, and this state is a posture in which the shield body 1 and the tail shield 2 are connected in a straight line. Reference numeral 9 denotes shield jacks, one end of which is attached to the shield body 1, and a plurality of shield jacks arranged at appropriate intervals on the inner circumference of the shield body 1 so as to press segments (not shown) on the other end.

Reference numeral 10 denotes an annular oil reservoir, which is formed by partitioning the inner periphery of the rear end of the shield body 1 and the outer periphery of the cylindrical portion 2b with an annular shield 11, and is filled with grease etc. It is designed to prevent the intrusion of earth and sand.

Next, the operation of the above embodiment will be explained with reference to FIGS. 5 and 6. First, when excavating a tunnel straight ahead, the second connecting means is in the state shown in FIGS. 1 and 6(a), that is, the end surface of the oblong hole 4 on the tail shield 2 side is in contact with the pin 6. Both hydraulic jacks 7 and 8 are in a locked state, stopping the flow of hydraulic pressure to maintain the straight-ahead posture.

If the shield jack 9 is operated in this state, its propulsive force will be transferred to each pin 6 through the brackets lb and lc.
The force is transmitted equally to the tail shield 2, and the tail shield 2 is pulled in the straight direction. Next, when the linear shape of the tunnel is bent upward, the hydraulic jack 8 is shortened by a stroke corresponding to a predetermined angle θ. In this case, the shield body 1 has a gap in which the diameter of the hole 5 is larger than the diameter of the pin 6 to allow the shortening stroke (for example, about 0.2 mm when the outer diameter of the shield body 1 is 3000 mm). Therefore, the core portion can be deflected upward with respect to the tail shield 2 by using it as a swinging fulcrum. At this time, the pin 6 moves relatively within the oblong hole 4, and the pin 6 moves to the side of the oblong hole 4 opposite to the tail shield 2.

FIG. 5 and FIG. 6(b) show the case where the direction is changed to the angle θmaX. When a predetermined turning angle is reached, the hydraulic jacks 8 and 7 are locked to maintain the turning attitude;
Activate shield jack 9 and proceed around the turn. To cancel the direction change state and return to the straight-ahead state, it is sufficient to extend the hydraulic jack 8 in the opposite direction to that described above. In this case, the swing fulcrum position does not change, and the pin 6 simply moves within the oblong hole. That's fine. On the other hand, when turning in the left-right direction, one of the hydraulic jacks 7 is extended and the other is shortened. In this case, the shield main body 1 is caused to swing from side to side in the shortening direction with respect to the tail shield 2 about the pin 6 as an axis, and the deflection angle is allowed to be large within the range of the stroke of the jack 7.

When the predetermined turning angle is reached and when returning to the straight traveling state, the same operation as in the case of turning in the vertical direction may be performed. In this embodiment, the case where the direction is changed upward is explained, but when the direction is changed downward,
A second connecting means having an oblong hole 4 is placed at the bottom, and a first connecting means having a circular hole 5 is placed at the top. If the hydraulic jack 8 is arranged in the same way as shown in Fig. 3, it will be extended when bending downward and shortened when returning straight, but if it is arranged at the lower side symmetrical to the position shown in Fig. 3. has the same effect as the case where the direction is changed upward.

In the embodiment described above, bending in the vertical direction is performed using the oblong hole 4 provided in the bracket 1b, but the present invention is not limited to the oblong hole 4, and another example will be explained with reference to FIG. FIG. 7 shows an alternative structure to the first connecting means in the upper part, in which 12 is a trunnion provided at the same position as the pin 6, and both ends are rotatably supported by the cylindrical part 2b and the bracket 2C. ing. Hole 12 of trunnion 12
A shaft 13 protruding from the side surface of the rib 1a is fitted into the hole a, and the diameter of the hole is sized to have a gap similar to that of the circular hole 5 between the shaft 13 and the outer diameter of the shaft 13. Even when bent in the vertical direction, it can freely slide within the hole 12a. A stopper 14 is fixed at the tip of the shaft 13 at a position apart from the trunnion 12 by a length that allows the angle 0IIlaX, as in the case where the length of the oval hole 4 is set. The stopper 14 serves to transmit the propulsive force of the shield jack 9 to the tail shield 2 via the trunnion 12 when the vehicle moves straight. The effect when turning in the horizontal and vertical directions is the same as in the case of the connecting means having the oblong hole 4.

[Effects of the Invention] As explained above, the present invention includes a first connecting means that is connected to either the upper or lower portion of the divided portion of the shield so that it can be bent horizontally and vertically, and the first connecting means that is relatively bendable left and right to the other side, and a second connecting means that connects in a relatively expandable and contractible manner,
The hydraulic jack for steering is expanded and contracted using the position of the first connecting means as a fulcrum, and the shield body is bent relative to the tail shield to change direction, so the tunnel excavation direction can be easily changed with a simple configuration. Moreover, it has a remarkable practical effect of being able to reliably change direction.

[Brief explanation of the drawing]

The drawings are all explanatory diagrams of embodiments according to the present invention, and the first
The figure is a side cross-sectional view of the shield tunneling machine divided into two parts, front and rear, Figure 2 is a cross-sectional view of II=II in Figure 1, and Figure 3 is a cross-sectional view of Figure 1.
- ■ Cross-sectional view, Figure 4 is an enlarged cross-sectional view of IV-IV in Figure 3,
FIG. 5 is an explanatory diagram of the operation when the linear shape of the tunnel is bent upward, FIG. 6 is an explanatory diagram of the operation of the connecting portion, and FIG. 7 is an explanatory diagram of the configuration of the main part of another embodiment. Patent Applicant Hitachi Construction Machinery Co., Ltd. Agent Patent Attorney Tadashi Akimoto Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6

Claims (1)

[Claims] 1. A shield excavator comprising a cylindrical shield body and a cylindrical tail shield connected to the rear part of the shield body via a connecting means, wherein the rear part of the shield body includes:
a first connecting means that connects the front portion of the tail shield facing the tail shield so that one of its upper and lower portions can be bent horizontally and vertically;
and a second connecting means that is relatively expandable and retractable, one end of which is connected to the shield main body side and the other end of which is connected to the tail shield side, and the expansion and contraction of the second connecting means connects the shield through the first connecting means and the second connecting means. A shield excavator characterized by being provided with at least two bending jacks for bending the main body and the tail shield horizontally and vertically. 2. The shield excavation according to claim 1, characterized in that a regulating means is provided between the shield body and the tail shield to regulate the amount of relative bending between the shield body and the tail shield by a bending jack. Machine. 3. The second connecting means includes a first member connected to either the shield main body or the tail shield and having a long elongated hole bored in the front-rear direction, and a shaft member connected to the other and engaged with the elongated hole. A shield excavator according to claim 1, characterized in that the shield excavator comprises a second member having: