JPH0449273Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a disk cutter that is attached to the cutter head of a tunnel excavator.

Prior Art As shown in Fig. 6, a pair of retainers c are fixed to a cutter head a via a pair of mounting brackets b, a shaft d is horizontally fixed to the pair of retainers c, and a bearing e is attached to the shaft d. A hub g equipped with a cutting ring f is attached through the hub g, and floating seals h are attached between both ends of the hub g and a pair of retainers c to form a sealed space i. A disk cutter in which lubricating oil for bearing e is sealed is known.

Problems to be Solved by the Invention Since such a disc cutter has a low water pressure resistance of the floating seal h, it is attached to a tunnel excavator A that excavates a tunnel from a vertical pile j to a seabed k as shown in FIG. 7, for example. In this case, the excavation ground (the seabed K) contains a lot of water and the disc cutter B
Since the pressurized water is high, the pressure difference between the internal pressure and external pressure of the floating seal h becomes large, and muddy water enters the space i from the floating seal h, causing damage to the bearing e and rotation of the cutter ring f. Impossibility will occur.

Means and action for solving the problem A cylinder is provided to balance the internal pressure and external pressure in the space so that there is no pressure difference between the internal pressure and external pressure of the floating seal even if the external pressure fluctuates. This is what I did.

Embodiment A cutter head 2 is rotatably supported at the tip of a cylindrical body 1 of a tunnel excavator, and a plurality of disk cutters 3 are attached to the cutter head 2.

As shown in FIG. 1, the disk cutter 3 has a pair of brackets 4, 4 fixed to both sides of the opening 2a of the cutter head 2, and a pair of retainers 5, 5 are fixed to the pair of brackets 4, 4, respectively. At the same time, the shaft 6 is inserted between the pair of retainers 5, 5.
is fixed horizontally, and cutter 7 is attached to this shaft 6.
A cylindrical hub 8 is rotatably supported via a bearing 9, and a pair of seal rings 10 are provided between both ends of the hub 8 and each retainer 5.
Floating seals 12, which are pressed together by O-rings 11, are attached to each to form a sealed space 13, and this space 13 is filled with lubricating oil.

A hole 14 is formed in the axial direction of the shaft 6, and a radial port 15 opens into the space 13 in the middle of the hole 14, and one end of the hole 14 is connected to the hole 16 of one retainer 5. A plug 17 is fitted and closed, and the other end of the hole 14 is open and communicated with one side chamber 19 of the cylinder 18 .

The cylinder 18 has a piston 21 inserted into a cylinder hole 20 drilled in the axis of the shaft 6 to form a chamber 19 on one side and a chamber 22 on the other side, and between the piston 21 and the screw plug 23. A stainless steel bellows 24 is attached, and the other side chamber 22 is covered with the bellows 24.
The hole 23a of the screw plug 23 and the hole 25 of the other retainer 5 communicate with the outside to introduce external pressure, and the piston 21 is pressed by the external pressure and is sealed in the space 13, the hole 14, and the port 15. The lubricating oil is pressurized so that the internal pressure is approximately equal to the external pressure.

A lubricating hole 26 is formed in the axial direction of the shaft 6 to open into the port 15 and is closed with a plug 27. When the plug 17 is removed, lubricating oil is injected through the lubricating hole 26 to drain the air in the space 13. The lubricating oil is discharged from the hole 14 so that the lubricating oil is completely enclosed in the space 13 to prevent air from entering.

As shown in FIG. 5, the cylinder 18 is formed by fitting a liner 31 into the hole 30 to form a cylinder hole 20, and fitting the piston 21 into the cylinder hole 20 through a packing 32 to form one side chamber 19 and the other side chamber. concubine 2
2 may be formed.

Effects of the invention: The internal pressure of the space 13 changes in response to changes in the external pressure, and the two are balanced, so the pressure between the outside and inside of the floating seal 12 is always balanced, eliminating pressure difference, and pressurized water is removed. Even when used in a tunnel excavator that excavates high ground, muddy water will not enter through the floating seal 12, and bearings will not be damaged or the cutter ring will not be able to rotate.

[Brief explanation of the drawing]

1 to 4 show embodiments of the present invention.
The figure is a sectional view of the disk cutter, FIG. 2 is a right side view, FIGS. 3 and 4 are front views of the cutter head, and FIG. 5 is a sectional view showing another embodiment of the disk cutter. The figure is a sectional view of a conventional example, and FIG. 7 is a diagram illustrating its defects. 2 is a cutter head, 5 is a retainer, 6 is a shaft, 7 is a cutter ring, 8 is a hub, 9 is a bearing, 12 is a floating seal, 13 is a space,
18 is a cylinder.

Claims (1)

[Scope of claim for utility model registration] A pair of retainers 5 fixed to the cutter head 2,
A hub 8 equipped with a cutter ring 7 is rotatably supported via a bearing 9 on a shaft 6 horizontally suspended between the hub 8 and a pair of retainers 5, 5.
In the disk cutter, a floating seal 12 is installed between each of the shafts 6 to form a sealed space 13, and a lubricating oil is sealed in this space 13.A cylinder hole 20 is formed in the shaft 6, A piston 21 is slidably inserted into the hole 20 to form a chamber 19 on one side and a chamber 22 on the other side. A disc cutter characterized by having a cylinder 18 that balances internal pressure and external pressure.