JPH0483095A - Tail seal of shield tunneling machine - 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 provides a method for preventing earth and sand or backfill material from entering the machine from between the tail skin plate and the segment of the shield body in a shield excavator. Regarding the tail seal.

[Conventional technology]

The tail seal of a shield tunneling machine is usually shown in Figures 6 to 8.
As shown in the figure, the base ends of the tail seal material 4, the inner protection plate 5, and the outer protection plate 6 are held between the inner plate 3a and the outer plate 3b of the tail seal mounting hardware 3 having a predetermined width dimension X, and the rivets are set. Tail seal skin plate 1 of the shield main body, which is integrated by tightening etc. as a constituent unit.
It is attached to the inner side so that it connects sequentially in the circumferential direction.

A brush-shaped or plate-shaped material is used as the tail sealing material 4, and this tail sealing material 4 closely adheres to the outer peripheral surface of the segment 2 and exhibits a sealing function.

Both the inner protection plate 5 and the outer protection plate 6 are made of spring steel, and the width of the part (base end) held by the tail seal mounting hardware 3 is X.
Regarding the dimensions, the width becomes wider from the part away from the tail seal mounting hardware 3, and it becomes 7 dimensions near the tip. The portions extending in the width direction overlap each other to protect the tail seal material 4 and assist in its sealing function.

The tips of each of the protection plates 5 and 6 are formed in a straight line, and the inner protection plate 5 contacts the outer circumferential surface of the segment 2 at the tip 7 (see FIG. 8), which is formed in a straight line.

[Problem to be solved by the invention]

In the conventionally used tail seal, the tip portion 7 that contacts the outer circumferential surface of the segment of the inner protection plate 5 is straight, so that the following problems occur.

(1) In the circular portions 2a and 2b on both sides of the normal circular shield segment (Fig. 11) and double shield segment (Fig. 12) having a cone-shaped cross section, the tip 7 of the inner protection plate 5 of the tail seal As shown in FIG. 9, the tail seal is circumscribed by the circular arc of the outer periphery of the segment 2, and in the reverse circular arc portions 2c and 2d that connect the circular portions 2a and 2b on both sides of the double shield segment (FIG. 12), the tail seal inner protection vi,
The tip end 7 of the segment 5 is inscribed in the arc of the outer periphery of the segment 2, as shown in FIG.

In either case, the tip 7 of the inner protection plate 5 is difficult to fit into the outer circumferential surface of the segment, so a gap is created between the outer circumference of the segment and the overlapping portions of adjacent inner protection plates 50 are in close contact with each other. (2) When the tip 7 of the inner protection plate 5 circumscribes the arc of the outer circumference of the segment as shown in Fig. 9, For the tail seal material 4
As the tip 7 in contact with the outer circumferential surface of the segment receives bending force due to the binding force of The tail seal material 4 is easily damaged. Furthermore, when the tip 7 of the inner image II plate 5 is inscribed in the arc of the outer periphery of the segment as shown in FIG. Become.

In view of the above points, the present invention minimizes the gaps between the inner protection plate and the segments and between adjacent inner protection plates by shaping the tip of the inner protection plate of the tail seal into a shape that easily conforms to the outer peripheral surface of the segment. The purpose is to improve the sealing function and prevent mutual damage between the inner protection plate and the tail seal material, and between the inner protection plate and the segments.

[Means to solve the problem]

In order to achieve the above object, the tail seal of the shield tunneling machine according to claim 1 is characterized in that the tip of the inner protection plate that circumscribes the arc of the outer periphery of the segment is formed into a concave substantially arc shape along the outer periphery of the segment. Features.

For the same purpose, the tail seal of the shield tunneling machine according to claim 2 is characterized in that the tip of the inner protection plate inscribed in the arc of the outer circumference of the segment is formed into a convex, substantially arc shape along the outer circumferential surface of the segment. The tail seal for a shield tunneling machine according to claim 3 is characterized in that a groove is provided in the center of the tip of the inner protection plate having a convex, substantially arc shape.

[Effect]

When the tip of the inner protection plate of the tail seal obliquely circumscribes the arc of the outer circumference of the segment, the cut of the outer circumference of the segment by the plane including the inner protection plate becomes an ellipse. Therefore, the tip of the inner protection plate is shaped like an approximately arc (concave when viewed from the proximal end of the inner protection plate) corresponding to this cut shape.
By doing so, the tip of the inner protection plate fits well with the outer circumferential surface of the segment, the gap between them can be minimized, and the overlapping parts of adjacent inner protection plates can also come into close contact with each other. This eliminates the possibility of the corner part of the tail sealing material being lifted up and damaging the tail seal material, or stress being concentrated at the center of the tip of the inner protective plate.

If the tip of the inner protection plate is obliquely inscribed in the arc of the segment's outer periphery, the cut of the segment's outer circumferential surface by the plane containing the inner protection plate becomes an ellipse in the opposite direction to the above.
By making the tip of the inner protection plate approximately arc-shaped (convex when viewed from the proximal end side of the inner protection plate) to correspond to this cut shape, the tip of the inner protection plate can be easily attached to the outer peripheral surface of the segment. This allows for the gap between them to be minimized, and the overlapping parts of adjacent inner protection plates to be in close contact with each other, which also prevents the corners of the tips of the inner protection plates from getting caught on the outer circumferential surface of the segments and damaging each other. It also disappears. In this case, if a groove is provided at the center of the tip of the inner protection plate, the tip of the inner protection plate will fit more easily into the outer peripheral surface of the segment.

〔Example〕

Embodiments of the present invention will be described below with reference to FIGS. 1 to 7.

As shown in FIGS. 6 and 7, the tail seal of the present invention comprises a tail seal material (a steel brush in the illustrated example) 4 and the base ends of an inner protection plate 5 and an outer protection plate 6 made of spring steel. The part is sandwiched between the inner plate 3a and outer plate 3b of the tail seal mounting hardware 3 having a predetermined width dimension χ, and is integrated by riveting or the like as a structural unit. It is the same as a conventional tail seal in that it is attached so as to be connected sequentially in the direction.

In the following description, of the inner protection plate 5, the normal circular shield segment (FIG. 11), the circular portions 2a on both sides of the double shield segment (FIG. 12) having a cocoon-shaped cross section,
2b, the outer protection plate 5 is used where the tip of the inner protection plate circumscribes the arc of the segment outer periphery.
a, where the tip of the inner protection plate is inscribed in the arc of the segment's outer periphery, such as the inverted circular arc parts 2c and 2d that connect the circular parts 2a and 2b on both sides of the double shield segment (Fig. 12). The one used is called an internal protection plate 5b.

Fig. 1 is a developed plan view of the external protection plate 5a, and Fig. 2 is a view of the contact state between the external protection plate 5a and the outer circumferential surface of the segment, viewed from the tunnel axis direction. The distal end 7a circumscribing the arc of the segment outer periphery of the segment 5a has a substantially concave arc shape when viewed from the base end side, and with a predetermined tail clearance secured between the tail skin plate 1 and the segment 2, the distal end 7a circumscribes the arc of the segment outer periphery. The portion 7a is arranged along the outer peripheral surface of the segment. By doing this, even if the tail clearance changes slightly, the tip 7 will remain the same as shown in Figure 8.
The gap between the tip end 7a and the outer circumferential surface of the segment can be kept small compared to the case where the protective plates 5a are straight, and the overlapped portions of the adjacent protection plates 5a can also be brought into close contact with each other.

Furthermore, the corner portion of the tip 7a may spring up and damage the tail seal material 4, or the tip 7a may spring up and damage the tail seal material 4.
This prevents stress from being concentrated near the center due to bending force from the center and causing cracks. In addition, in order to prevent mutual damage of the protection plates 5a and damage to the tail seal material 4, the protection plates 5a
It is best to round the corners of a as shown in the figure.

Fig. 3 is a developed plan view of the inscribed protection plate 5b, and Fig. 4 is a diagram showing the state of contact between the inscribed protection plate 5b and the outer peripheral surface of the segment, as seen from the tunnel axis direction. The distal end portion 7b inscribed in the arc of the outer periphery of the segment of the protective plate 5b has a convex substantially arc shape when viewed from the base end side, and a predetermined tail clearance is secured between the tail skin plate 1 and the segment 2. In this state, the tip portion 7b is aligned with the outer circumferential surface of the segment. By doing this, as with the external protection plate 5a, even if the tail clearance changes somewhat, compared to the case where the tip 7 is made straight as shown in FIG.
The gap between the tip portion 7b and the outer circumferential surface of the segment can be kept small, and the overlapping portions of adjacent protection plates 5b can also be brought into close contact with each other. Double shield segment (
Fig. 12) Reverse circular arc parts 2c and 2b are circular parts 2a and 2b on both sides.
Since the radius of curvature is smaller than that of the 300 mm, it is particularly effective in enhancing the sealing effect in this area. Further, by forming the tip portion 7b into a convex arc shape, it is possible to prevent the corner portion of the tip portion 7b from getting caught on the outer peripheral surface of the segment and causing mutual damage. In this case as well, it is preferable to round the corners of the protection plate 5b as shown in the figure.

FIG. 5 is a developed plan view of the grooved inscribed protection plate 5b, and as shown in the figure, the protection plate tip 7 has a convex, substantially arc shape.
By providing a slit 8 in the center of b, it is possible to give elasticity to the tip 7b and make it more compatible with the outer peripheral surface of the segment, and it is also effective in preventing cracks due to stress concentration. It is.

[Effect of the invention] The effects of the present invention can be summarized as follows.

(i) For both external protection plates and internal protection plates, the tips of the protection plates fit easily into the outer peripheral surface of the segment compared to conventional protection plates, and the overlapping parts of adjacent protection plates tend to come into close contact. It is expected that the sealing function will improve.

(ii) With the external protection plate, it is possible to prevent the tail seal material from being damaged by the raised corners of the protection plate as in the conventional case, and it is possible to reduce stress concentration at the tip of the protection plate.

(iii) In the case of the internal protection plate, it is possible to prevent the corner portions of the tips of the protection plates from getting caught on the outer peripheral surfaces of the segments and damaging each other as in the conventional case.

(iv) The grooved internal protection plate allows the tip of the protection plate to fit better with the outer circumferential surface of the segment, and is also effective in preventing stress concentration at the tip.

[Brief explanation of the drawing]

Fig. 1 is a developed plan view of a circumscribing protection plate of a tail seal according to the present invention, Fig. 2 is a view of the state of contact between the circumscribing protection plate and a segment, viewed from the tunnel axis direction, and Fig. 3 is a tail seal according to the present invention. FIG. 4 is a diagram showing the state of contact between the internal protection plate and the segment as seen from the tunnel axis direction. FIG. 6 is a side sectional view showing the installed state of the tail seal; FIG. 7 is a side sectional view showing the sealed state of the tail seal; FIG. 8 is a developed plan view of the conventional protection plate; Figures 9 and 10 are views of the contact state between the conventional protection plate and the segments, viewed from the tunnel axis direction, Figure 11 is an assembly diagram of the circular shield segment, and Figure 12 is an assembly diagram of the double shield segment. It is. 1...Tail skin plate, 2...Segment,
3... Tail seal mounting hardware, 4... Tail seal material, 5... Inner protection plate, 5a... External protection plate, 5
b... Inner protection plate, 6... Outer protection plate, 7...
- Linear tip of conventional protection plate, 7a... Arc-shaped tip of external protection plate, 7b... Arc-shaped tip of internal protection plate, 8... Division groove. 11 Figure 2 Patent Applicant Hitachi Construction Machinery Co., Ltd. Agent Patent Attorney Tadashi Akimoto Minoru 2...-Gifment Zeng 5 Figure 5b--Cause #Pressed Claw Protection Tile 7b-All 5A, & Japanese Map Segment 6th Ward 4--Su-Rujiru Talented 5-R Power Koi! l] Ho 11 [:λ-da; 6---Tato A
1" 14 spears 4 (non-reaching, Figure b 5b... Inner bar rough shield protection 7b - Town nori part '4' I eaves 8 - First trial 115 outside Figure 7... Tail span plate 2. -teri" outside 3...~f-runor tori 4 sun 4j course 4...naru seal non-number 5...-inside 4!...] 4 representative ash 622. Tatoge'Ii gago 4 square mi number 8 IA゛Figure 10 Figure C

Claims (1)

[Scope of Claims] 1. The tail of the shield main body is formed by holding and integrating the tail seal material and the base end portions of the inner protection plate and the outer protection plate with tail seal mounting hardware of a predetermined width, and In the tail seal of a shield excavator, which is attached to the inside of a skin plate so as to be connected sequentially in the circumferential direction, the tip of the inner protection plate, which circumscribes the arc of the outer periphery of the segment, is shaped like a concave shape along the outer periphery of the segment. A tail seal for a shield tunneling machine characterized by an arc shape. 2. The tail seal material and the proximal ends of the inner protection plate and outer protection plate are held and integrated by tail seal mounting hardware of a predetermined width, and a circular structure is formed inside the tail skin plate of the shield body. In the tail seal of a shield tunneling machine that is attached sequentially in the circumferential direction, the tip of the inner protection plate inscribed in the arc of the outer periphery of the segment is formed into a convex substantially arc shape along the outer periphery of the segment. A tail seal for a shield tunneling machine featuring the following. 3. The tail seal for a shield excavator according to claim 2, wherein a groove is provided at the center of the tip of the inner protection plate.