JPH0245355Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a type of shield excavator that expands and contracts in the excavation direction, and in particular, a seal structure of a reciprocating sliding part between a hood part and a tail part that are connected in an axial direction of expansion and contraction movement. This invention relates to a shield excavator with improved sealing performance.

In order to significantly improve the excavation speed, a shield excavator is constructed in which a hood part b having a cutter part a for excavating a face and a tail part d for assembling a segment c are telescopically connected, as shown in Fig. 1. Already known. In general, this shield tunneling machine has a hood part b and a tail part d having the same diameter, and the front end of the tail part d is fitted into the rear end of the hood part b so as to be able to reciprocate in the axial direction. The fitting part e has a fitting part e, and the sliding contact part between the fitting part e and the hood part b is provided with a sealing member f for liquid-tightly sealing the space between them (see FIG. 2). . However, in the case of a conventional shield tunneling machine, for example, as shown in FIG. 2, a sealing member f that slides into contact with the inner peripheral part of the hood part b is integrally provided at the tip of the fitting part e, etc. Therefore, if the gap g between the outer periphery of the fitting part e and the inner periphery of the hood part b changes greatly during pitting operation or reciprocating sliding during curve construction, the seal member f will not be able to follow it. There was a problem in that the sealing performance deteriorated.

The present invention was devised to solve this problem, and its purpose is to follow the change even if the gap size between the outer periphery of the tail part and the inner periphery of the hood part changes greatly. The object of the present invention is to provide a shield excavator with high sealing properties that can reliably seal between these.

In order to achieve the above object, the present invention includes a cylindrical hood part having a cutter part at the front end part, and an annular hollow part formed in the rear end part of the hood part, which is fitted so as to be movable in the axial direction. The cylindrical tail part and the annular air above
In the shield tunneling machine, the shield excavator is provided with a sealing means for sealing between the hood part and the tail part, and the sealing means is fitted on the outer periphery of the tail part via a packing so as to be slidable in the axial direction. and a seal ring that is secured to the inner periphery of the hood part with play in the axial and radial directions, and a seal ring that surrounds the outer periphery of the tail part and has one end fixed to the seal ring and the other end fixed to the hood part. It consists of a flexible seal cylinder that seals between the seal ring and the hood part while allowing tilting.

According to this configuration, the seal ring of the sealing means for sealing the annular cavity between the hood part and the tail part can tilt to follow the tail part within the hood part, and can also prevent the tail part from moving in the axial direction. The seal cylindrical body seals between the seal ring and the hood while allowing the seal ring to tilt due to the tilting of the tail. Even if the dimension between the outer periphery of the hood part and the tail part changes greatly, the change can be followed and the gap between the hood part and the tail part can be reliably sealed.

A preferred embodiment of the present invention will be described below in detail with reference to the accompanying drawings.

In Fig. 3, 1 is a cylindrical hood part having a rotary cutter part 2 for excavating a face at the front end, 3 is provided on the rear side of the hood part 1 so as to be able to expand and contract, and has segments inside. This is a tail portion having an erector 5 for assembling 4. The tail portion 3 is formed into a cylindrical shape having approximately the same diameter as the hood portion 1, and has a cylindrical fitting fitted into the rear end portion of the hood portion 1 so as to be movable back and forth in the axial direction thereof. The portion 6 is integrally formed. That is,
The fitting part 6 is formed to have an outer diameter smaller than the inner diameter of the hood part 1 so that it can be tilted slightly and reciprocated in the axial direction within the hood part, and has a length slightly longer than one segment 4. There is. Further, inside the fitting part 6, there is a holding jack 8 which presses the shoe 7 against the end of the assembled segment 4 to maintain the posture of the tail part 3, and a shoe 10 which presses the shoe 7 against the end of the assembled segment 4 to maintain the attitude of the tail part 3. A plurality of digging jacks 11 are provided in the circumferential direction to push the hood portion 1 forward.

Note that 12 is a tail seal provided at the rear end of the tail portion 3 to seal between this and the outer circumferential portion of the assembled segment 4. Also,
A cylindrical cover plate 14 is provided at the rear end of the hood part 1 and extends to the rear tail part 3 to cover a stepped part 13 formed between the rear end part of the hood part 1 and the front end part of the tail part 3. This prevents earth and sand from entering or falling into the stepped portion 13 that would impede the sliding movement. This cover plate is made of a flexible member (for example, a thin steel plate or a thin spring steel) so as to allow bending (tilting) between the hood part 1 and the tail part 3 during curve construction. There is. A means 15 is provided between the hood part 1 and the fitting part 6 for liquid-tightly sealing the space between them while allowing them to slide against each other.
This sealing means 15 is fitted around the outer peripheral part of the fitting part 6 so as to be slidable in the axial direction, and includes a seal ring 17 having a sealing surface 16 on the inner peripheral surface, and an inner peripheral part of the hood part 1. It is mainly composed of a flexible seal cylinder 19 that extends over the seal ring 17 from the hood part 1 and forms a seal wall 18 between the hood part 1 and the seal ring 17.

That is, the seal ring 17 is shown in FIGS. 4 to 6.
As shown in the figure, it is formed in a size that has an appropriate distance between it and the hood part 1 to allow the tilting of the hood part 1, and has a plurality of ring grooves 20 on its inner circumference.
Each ring groove 20 has a seal ring 17 and a fitting part 6.
A U gasket 21 is fitted to seal between the two. Furthermore, a lubricating oil supply passage 22 for supplying lubricating oil to the inner circumference between the ring grooves 20 is formed in the seal ring 17, and an inlet 23 opened at the front end thereof has a lubricating oil supply pipe led from an oil supply source. 24
is connected. The seal ring 17 is disposed within an annular gap 25 formed between the outer periphery of the fitting part 6 and the inner periphery of the hood 1, and is placed in the hood to secure this annular gap 25. At the rear end of 1, there is a flange-shaped sliding guide block 26 extending radially inward from this, and at the tip of the fitting part 6, a flange-shaped anti-swing guide extending radially outward from this. A block 27 is provided respectively. Note that there is a digging sliding mechanism between the inner periphery of the sliding guide block 26 and the outer periphery of the fitting part 6 and between the outer periphery of the vibration prevention guide block 27 and the inner periphery of the hood part 1. A certain amount of clearance is formed. In particular, a dust seal 28 is provided at the rear end of the sliding guide block 26 to seal between this and the outer periphery of the fitting part 6 to prevent dirt and sand from entering. Further, a dust seal 29 is provided at the rear of the seal ring 17 to seal between the seal ring 17 and the outer peripheral portion of the fitting portion 6.

On the other hand, the seal cylinder 19 is made of a rubber cylinder surrounding the fitting part 6 within the annular cavity 25,
One end of the base end is fixed to the front end of the sliding guide block 26, and the free end is fixed to the rear end of the seal ring 17 in a fluid-tight manner. Note that this fixing means and the dust seal 2
Bolts and retainers are used as means for fixing the seals 8 and 29, and these seal cylinders 19 and the like are attached so as to be replaceable. Seal ring 17 and hood part 1
On the outer periphery of the seal cylinder 19 forming the seal wall 18 between the
An annular protective ring portion 30 is provided integrally extending from the rear end of the seal ring 17 to restrict the backward movement of the seal ring 17 and prevent compressive deformation of the seal cylinder 19. . That is, the backward movement of the seal ring is restricted by the protection ring portion 30 coming into contact with the front end of the sliding guide block 26. In addition, in order to prevent the seal cylinder 19 from being pulled or damaged due to the forward movement of the seal ring 17, the front end of the seal ring 17 is placed against the inner circumferential portion of the hood portion 1. A stopper portion 31 is provided to restrict forward movement. In this case, the seal ring 17 including the protection tube part 30 is slightly shorter in length than the length between the sliding block 26 and the stopper 31, and has an outer diameter smaller than the inner diameter of the hood part 1, as shown in FIG. By being formed slightly smaller, it is secured to the inner periphery of the hood portion 1 with play in the axial and radial directions, so that it can be tilted to follow the tail portion 3.

Furthermore, a pressurized water inlet 33 is formed at the front end of the hood part 1 to introduce pressurized water into the annular hollow part 32 defined by the cover plate 14 on the fitting part 6. Mouth 33
A water supply pipe 34 led from a pressurized water supply source is connected to. Therefore, by supplying pressurized water, the vacuum phenomenon caused by the expansion of the hollow part 32 due to the mutual stretching movement between the hood part 1 and the tail part 3 is eliminated, and the cover plate 14 and the tail part 3 are
It is possible to prevent dirt and the like from being sucked into the hollow portion 32 through the gap between the two.

Next, the operation of the embodiment will be described.

The shield excavator excavates the face by assembling the segments 4 using the erector 5 and expanding and contracting the hood part 1 and the tail part 3 using the holding jack 8 and the digging jack 11. FIG. 3 shows a situation in which the segments 4 are being assembled with the hood part 1 and the tail part 3 mutually contracted.
In order to suppress the reaction force caused by the propulsion of the hood part 1, the holding jack 8 is always attached to the already assembled segment 4.
As shown in FIG. 7, when the propulsion of the hood part 1 and the assembly of the segments 4 are completed at the same time, the holding jack 8 is extended in order to assemble the next segment. The tail section 3 is propelled by the operation. At this time, by simultaneously contracting the digging jack 11, the tail portion 3 approaches the hood portion 1 and enters a contracted state. Once the segment is in the contracted state, the segment 4 is assembled by contracting only some of the holding jacks 8 that will get in the way of inserting the segment assembly, forming a space in which to assemble the segment 4, and assembling the segment 4. The hood part 1 is propelled while assembling (pieces) 4 in order, and the same operation is then repeated to form a tunnel. In such an excavator, the seal at the connection between the hood part 1 and the tail part 3 is an important point. However, according to the present invention, the seal ring 17 fitted onto the fitting part 6 of the tail part allows the fitting part 6 to slide in the axial direction, and the gap between the fitting part 6 and the seal ring 17 is maintained. In addition to sealing, the seal cylinder 19 spans from the hood part 1 to the seal ring 17.
Since the seal ring 17 seals between the seal ring 17 and the hood part 1 while allowing the tilting of the seal ring 17 due to the tilting of the tail part 3, a reliable seal can be achieved at the connection part.

In summary, according to the present invention, the seal ring of the sealing means for sealing the annular cavity between the hood part and the tail part can tilt to follow the tail part within the hood part, and can tilt in the axial direction of the tail part. The outer periphery of the seal cylinder is sealed while allowing movement, and the seal cylinder seals between the seal ring and the hood while allowing the seal ring to tilt due to the tilting of the tail. Even if the dimension between the hood and the outer periphery of the tail changes greatly, the change can be followed and the gap between the hood and the tail can be reliably sealed.

[Brief explanation of the drawing]

Figure 1 is a schematic cross-sectional view of a conventional shield tunneling machine.
Fig. 2 is an enlarged view of part A in Fig. 1, Fig. 3 is a schematic sectional view of a shield tunneling machine showing an embodiment of the present invention, Fig. 4 is an enlarged view of part B in Fig. 3, and Fig. 5 is an enlarged view of part B in Fig. 3. FIG. 4 is an enlarged view of part C, FIG. 6 is a sectional view showing a state in which the hood part and the tail part are mutually extended in FIG. 4, and FIG. 7 is a sectional view for explaining the movement of the shield tunneling machine. In the figure, 1 is a hood part, 2 is a cutter part, 3 is a tail part, 16 is a sealing surface, 17 is a sealing ring,
19 is a seal cylinder.

Claims (1)

[Scope of utility model registration request] a cylindrical hood portion having a cutter portion at the front end;
A cylindrical tail part is formed in the rear end of the hood part and is fitted so as to be movable in the axial direction, and a cylindrical tail part is provided in the annular hollow part to seal between the hood part and the tail part. In the shield excavator, the sealing means is fitted on the outer periphery of the tail part via a packing so as to be slidable in the axial direction, and the sealing means is fitted on the inner periphery of the hood part so as to be slidable in the axial and radial directions. A seal ring is locked with play, and one end is fixed to the seal ring surrounding the outer periphery of the tail part and the other end is fixed to the hood part, allowing the seal ring to tilt while sealing between the seal ring and the hood part. A shield excavator comprising a flexible seal cylinder.