JPH0311360B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a shield tunneling machine, and particularly to a seal structure for a drive shaft of a cutter drum.

In general, shield tunneling machines are broadly classified into three types depending on the support method for the drive shaft of the cutter drum: an intermediate support method as shown in FIG. 3, a center shaft method as shown in FIG. 4, and a peripheral support method as shown in FIG. In each figure, 21 is the shield body, 22 is the partition wall,
23 is a cutter drum; 24 is a drive shaft for the cutter drum; 25 is a hydraulic motor that rotates the drive shaft via a pinion 26 and a large gear 27;
Reference numeral 8 indicates a face chamber, and 29 indicates a propulsion jack. In the intermediate support system shown in FIG. In the center shaft method, the drive shaft 24 is supported by the partition wall 22 on its outer peripheral surface via the sealing material 30, and in the peripheral support method shown in FIG. It is supported by the main body 1 via a sealing material 30, and in either method, the sealing material 30 prevents muddy water or earth and sand in the face chamber 28 from entering the inside of the shield main body.

By the way, when the distance excavated by the shield tunneling machine is long, it is natural that the sealing material is subject to severe wear and tear. Conventionally, as shown in FIGS. 6 and 7, an example of the intermediate support method is the sealing material A large number of stages are arranged in series to maintain sealing performance. However, in this method, there is a limit to the number of stages in which the sealing materials 30, 30, etc. can be installed, and all of the sealing materials in each stage are in contact with the seal contact surface 31 during the operation of the shield excavator, that is, while the cutter drum 24 is rotating. As a result, wear was unavoidable and sealing performance could not be ensured during long excavations.

This invention has been made to solve the above-mentioned conventional problems, and provides a shield excavator that can ensure sealing between the drive shaft of the cutter drum and the bulkhead over a long period of time. The purpose is to That is, the present invention provides a shield excavator in which a partition is provided at the tip of a cylindrical shield body, and a drive shaft of a cutter drum is rotatably attached to the partition, in which a seal ring is disposed between the partition and the drive shaft. In addition, a sealing material is disposed between the seal ring and the partition wall and the drive shaft, and the seal ring is selectively fixed to either the drive shaft or the partition wall. It is characterized by:

Hereinafter, an embodiment in which the present invention is applied to an intermediate support type shield tunneling machine will be described with reference to FIGS. 1 and 2.

In FIG. 1, a partition wall 2 is provided at the tip of a shield body 1 to partition a face chamber 15 from the inside of the main body, and a drive shaft 4 of a cutter drum 3 is attached to this partition wall 2. An internal gear 5 is provided on the inner surface of the drive shaft 4, and a partition wall 2 is attached to the internal gear 5.
The pinions 7 of the plurality of hydraulic motors 6 are engaged with each other, and the drive shaft 4 is driven by the operation of the hydraulic motor 6.
The cutter drum 3 rotates accordingly.

Inner and outer seal rings 8 and 9 are arranged between the partition wall 2 and the inner and outer peripheral surfaces of the drive shaft 4, respectively.
First sealing materials 10 and 11 are provided between the inner circumferential surface of the inner seal ring 8 and the partition wall 2 and between the outer circumferential surface of the outer seal ring 9 and the partition wall 2, respectively. The outer peripheral surface of the ring 8 and the drive shaft 4
and between the inner circumferential surface of the outer seal ring 9 and the drive shaft 4, second sealing materials 12 and 13 are provided, respectively, and each sealing material is installed in multiple stages as shown in FIG. There is. The inner and outer seal rings 8, 9 have a plurality of fixing plates 14a, 14b fitted between their end faces and the end faces of the drive shaft 4 or the partition wall 2 so as to form an annular shape as a whole. It is adapted to be selectively fixed to the partition wall 2. In the illustrated example, the inner and outer rings 8, 9 are fixed to the drive shaft 4.

Next, the usage status of the above-mentioned device will be explained.
At the beginning of excavation, the inner and outer rings 8 and 9 are fixed to the drive shaft 4 as shown in the figure, that is, the first sealing material 1
Only 0 and 11 are used, and the second seal members 12 and 13 are not used, and the mounting gap is filled with grease. In this state, the inner and outer rings 8 and 9 are connected to the drive shaft 4.
The second seal members 12 and 13 rotate together with the partition wall 2, so that no wear occurs on the second seal members 12 and 13.

If wear or damage occurs to the first sealing materials 10, 11 during excavation, the fixing plates 14a, 14b are removed, the inner and outer rings 8, 9 and the partition wall 2 are fixed by the fixing plates, and the second sealing materials 12, 13 is used. As described above, the second sealing materials 12 and 13 are not worn out during the use of the first sealing materials 10 and 11 and are as good as new.
Since the sealing materials 0, 11 and the second sealing materials 12, 13 can be used in stages, the sealing performance of the drive shaft 4 can be ensured over a long period of time. The order in which the first and second sealants are used may be reversed.

Although the intermediate support method has been described in the above embodiment, the present invention can also be applied to other cutter support methods. Furthermore, the inner and outer seal rings may be provided in multiple layers, and the sealing materials may be provided in sequence accordingly.

The present invention is as described above, and when one of the sealing materials disposed between the seal ring, the bearing, and the partition wall is used, there is no wear on the other, and therefore each seal Materials can be used in stages, and the sealing performance of the bearing can be ensured over a long period of time, making it particularly effective for construction work where the excavation distance is long.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal side view showing an embodiment of the present invention, Fig. 2 is an enlarged view of a part of the same as above, Figs. 3 to 5 are longitudinal side views showing a conventional example, and Fig. 6 is an intermediate support system. 7 is an enlarged view of a part of the same as above. DESCRIPTION OF SYMBOLS 1... Shield body, 2... Partition wall, 3... Cutter drum, 4... Drive shaft, 8... Inner seal ring, 9... Outer seal ring, 10, 11...
first sealing material, 12, 13... second sealing material.

Claims (1)

[Claims] 1. In a shield excavator in which a partition is provided at the tip of a cylindrical shield body, and a drive shaft of a cutter drum is rotatably attached to this partition, a seal ring is disposed between the partition and the drive shaft, and a seal ring is provided between the partition and the drive shaft. A sealing material is disposed between a seal ring and the partition wall and the drive shaft, respectively, and the seal ring is selectively fixed to either the drive shaft or the partition wall. Shield excavator.