JPH0689630B2 - Vertical shaft entrance packing device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an entrance packing device provided in an entrance for launching or reaching a shield excavator in a vertical shaft, and particularly to improvement of a non-return fitting thereof.

[Prior Art] At the entrance for starting or reaching a shield excavator in a vertical shaft, excavated earth and sand and groundwater enter the vertical shaft through the annular gap between the inner surface of the entrance and the outer surface of the shield excavator or the segment party for the primary lining of tunnels. An entrance packing device is required to prevent the inflow.

In the case of a starting entrance, the entrance packing device seals the annular gap between the inner surface of the entrance and the outer surface of the shield excavator against external pressure when the shield excavator starting from the vertical shaft is located inside the entrance. Then
Then, when the segment is located inside the entrance, it is necessary to seal the annular gap between the outer peripheral surface of the segment and the inner surface of the entrance against the external pressure. In general, the outer dimensions of the segment are smaller than the outer dimensions of the shield excavator, so when the segment is located inside the entrance compared to the width of the annular gap when the shield excavator is located inside the entrance. The width of the annular gap is increased. Therefore, the entrance packing device provided in the starting entrance must be capable of maintaining the sealing function in response to changes in the width of the annular gap.

Further, in the case of the entrance for arrival, a method is generally used in which an internal pressurizing container having an outer shape larger than that of the shield excavator is arranged in advance in the entrance and the shield excavator for arrival is received in this container. In such a construction method, the shield excavator reaches the inside of the container, and the subsequent segment is provided in the entrance, and then the container is removed from the entrance. Therefore, the entrance packing device provided at the arrival entrance needs to seal the annular gap between the outer peripheral surface of the container and the inner surface of the entrance, and then seal the annular gap between the outer peripheral surface of the segment and the inner surface of the entrance. As with the entrance packing device of the entrance, it must be able to maintain the sealing function in response to changes in the width of the annular gap.

Japanese Unexamined Patent Publication No. 60-148994 discloses a typical conventional entrance packing device for a starting entrance. This entrance packing device is an elastic packing member for sealing an annular gap generated between the inner surface of the opening of the entrance and the outer peripheral surface of the shield excavator or the tunnel primary lining segment, and the back surface of the elastic packing member. Is provided with a non-return fitting for supporting the entire circumference against external pressure.The non-return fitting includes a fixing portion fixed to the entrance together with the elastic packing member, and an end of the fixing portion on the inner side of the entrance opening. And a swing plate portion that extends from the portion toward the center of the entrance opening and is swingably displaced with respect to the fixed portion.

When such an entrance packing device is used, the inner peripheral edge of the elastic packing member is in close contact with the outer peripheral surface of the shield excavator or the segment, and each rocking plate portion that supports the back surface of the elastic packing member is inclined and its tip end is inclined. Is dimensioned so as to be able to abut the outer peripheral surface of the shield excavator or the segment, so that the rocking plate portion can support the back surface of the elastic packing member against the earth pressure or water pressure from the outside. Further, since the rocking plate portion can rock, the tip of the rocking plate portion can smoothly transition from a state of contacting the outer peripheral surface of the shield excavator to a state of contacting the outer peripheral surface of the segment.

[Problems to be Solved by the Invention] However, since the above-described conventional rocking plate portion can be rocking-displaced to a position along a transverse cross section (a cross section perpendicular to the axis) of the entrance opening, an excessive number of segment parties with respect to the entrance opening. When the tip end of the oscillating plate portion comes into contact with the outer peripheral surface of the segment in the above-mentioned cross section passing through the oscillating center of the oscillating plate portion due to such eccentricity, the oscillating plate portion is located at the so-called dead center. Therefore, it may be difficult to return the segment toward the center of the entrance opening thereafter, or the rocking plate portion may be destroyed by an unreasonable return force, and as a result, the sealing function may be impaired.

Therefore, an object of the present invention is to provide an entrance packing device capable of preventing a situation in which the swinging function of the swinging plate portion of the check metal fitting is impaired and performing reliable sealing.

[Means for Solving the Problems] In order to achieve the above object, according to the present invention, an entrance of a vertical shaft for starting or reaching a shield excavator is to seal an annular gap generated in the entrance opening. In an entrance packing device for a vertical shaft, which comprises an emotional elastic packing member and a non-return fitting for supporting the back surface of the elastic packing member against external pressure, the non-return fitting is fixed to the entrance together with the elastic packing member. A fixed portion, a swing plate portion extending from an end portion on the inner side of the entrance opening of the fixed portion toward the center of the entrance opening, and swingably displaced to the fixed portion, and the swing plate. When the rocking plate is located at the minimum distance from the center of the entrance opening, the rocking plate moves so that the rocking plate takes an inclined posture with respect to the cross section of the entrance opening. It is configured to include a stopper portion that regulates a moving range.

[Operation] In the entrance packing device having the above configuration, when the swing plate portion of the check metal fitting is located at the position of the minimum distance from the center of the entrance opening, the swing plate portion is inclined at an acute angle with respect to the cross section of the entrance opening. Since the swinging range of the swinging plate is regulated by the stopper so that the swinging plate takes a posture, it is possible to reliably prevent the swinging plate from taking a so-called dead center position. Therefore, even if, for example, the segment returns from the tip of the oscillating plate portion due to excessive eccentricity and then returns toward the center of the opening of the entrance, the oscillating plate portion may undergo oscillating displacement according to the movement of the segment. You can Therefore, reliable sealing can always be performed.

Embodiments Embodiments of the present invention will be described in detail below with reference to the drawings.

1 to 4 show a first embodiment in which the present invention is applied to a starting entrance. With reference to these figures, an entrance packing device, generally designated by the numeral 10, is provided at a starting entrance, ie, a starting entrance 2 formed in a pit wall of a vertical shaft. The entrance packing device 10 includes an annular elastic packing member 11 for sealing an annular gap that may occur in the opening of the entrance 2, and a non-return fitting for supporting the back surface of the elastic packing member 11 against external pressure. It has 12 and.

As shown in FIG. 3, an elastic packing member made of rubber or the like
Reference numeral 11 has a circular hole 13 having a diameter smaller than the outer dimension of the segment 3 indicated by an imaginary line, and the elastic packing member 11 is provided with a method described later so that the circular hole 13 is concentric with the opening of the entrance 2. It is attached to 2. It should be noted that the shield excavator 4 has a larger outer dimension than the segment 3, as indicated by a phantom line in FIG. 3.

The check metal fittings 12 are arranged in the circumferential direction over the entire circumference of the entrance, and are fixed to the entrance 2 together with a plurality of fixing parts 14 fixed to the entrance 2 together with the elastic packing material 11, and swingably connected to the fixing parts 14. The rocking plate portion 15 is provided. In the illustrated embodiment, the fixing portion 14 and the elastic packing member 11 are fixed to the pit wall of the entrance 2 by a stud bolt 16 provided on the peripheral edge of the opening of the entrance 2 and a nut 17 screwed onto the bolt 16. Further, the elastic packing member 11 and the fixing portion 14
An annular pressing plate 18 along the outer peripheral edge of the elastic packing member 11 is interposed between and.

To describe the mounting structure of the oscillating plate portion 15 in more detail,
Each oscillating plate portion 15 extends from the end of the fixed portion 14 on the inner side of the entrance opening toward the center of the entrance opening, and via a hinge pin 19 extending parallel to the fixed portion 14 in the tangential direction of the entrance opening. Are connected so that they can be swung and displaced.

As shown in FIG. 4, the oscillating plate portion 15 is dimensioned so that its tip can contact the outer peripheral surface of the shield excavator 4 or the segment 3 in an inclined state. Therefore, when the oscillating plate portion 15 is in contact with the outer peripheral surface of the shield excavator 4 or the segment 3, the elastic packing member 11 has its inner peripheral edge in close contact with the outer peripheral surface of the shield excavator 4 or the segment 3. The back side is firmly supported by the rocking plate portion 15 against external pressure such as earth pressure and water pressure, and reliable sealing can be performed.

According to the present invention, as shown in FIG. 1, in the non-return fitting 12, when the swing plate portion 15 is in the position of the minimum distance from the center of the opening of the entrance 2, the swing plate portion 15 has a cross section (a cross section perpendicular to the axis) of the entrance opening. A stopper portion 20 that restricts the swing range of the swing member 15 is provided so as to take an inclined posture that forms an acute angle θ. Here, the stopper portion 20 is composed of a bolt that is screwed into a screw hole provided in the extension portion of the fixed portion 14.

In the entrance packing device having the above configuration, the shield excavator 4 and the segment 3 are installed in the entrance 2
Even if the opening is excessively eccentric,
15 is the position along the cross section of the entrance opening (θ = 0
)), That is, the so-called dead center position can be reliably prevented. Therefore, even if the shield excavator 4 or the segment 3 that is excessively eccentric returns toward the center of the opening of the entrance 2, the swing plate portion 15 swings according to the movement of the shield excavator 4 or the segment 3. can do. Therefore, reliable sealing can always be performed.

FIG. 5 shows a second embodiment of the present invention. In the figure, the same components as those in the first embodiment are designated by the same reference numerals. In this embodiment, the swing plate portion 15 is swingably connected to the fixed portion 14 via the flexible member 21. That is, when the flexible member 21 is bent and deformed, the swing plate portion 15 can swing with respect to the fixed portion 14. In addition, in this embodiment, the swing plate portion 15 is attached to the fixed portion 14.
The stopper portion 22 is formed so as to be able to contact the end face of the rocking plate 22. Since the stopper portion 22 has an inclination angle, the rocking plate portion 15 has an acute angle θ with respect to the cross section of the entrance opening passing through the rocking center. It is possible to swing to the position where Therefore, also in the second embodiment, the same operational effect as the first embodiment can be obtained.

In the above-described embodiment, the stopper portions 20, 22 and the like are provided on the fixed portion 14, but as shown in FIG. 6, the swing plate portion 15 can be integrally or adjustable with the stopper portion 23 that performs the same function. It may be provided separately.

Further, in the embodiment described above, the plurality of fixing portions 14 are arranged in an annular shape, but as shown in FIG.
A fixed portion 14 that extends in an annular shape along the inner circumference of the opening of the entrance 2 may be provided. In this case, a plurality of rocking plate portions 15 arranged at intervals along the inner circumference of the entrance opening. Each of them is swingably connected to the fixed portion 14.

Although the illustrated embodiment has been described above, the present invention is not limited to the embodiment of the above embodiment, and various modifications may be made to the constituent elements within the scope of the invention described in the claims. You can Further, the above-described configuration according to the present invention can be similarly applied to the entrance packing device of the arrival entrance.

[Effects of the Invention] As is clear from the above description, according to the present invention, it is possible to prevent the swingable swing plate portion from reaching the dead center position by the stopper portion, so that reliable sealing is always performed. It is possible to provide an entrance packing device capable of

[Brief description of drawings]

1 is a longitudinal sectional view of an entrance packing device showing the first embodiment when the present invention is applied to a starting entrance, and FIG. 2 is a front view of a non-return fitting of the entrance packing device shown in FIG. FIG. 3 is a schematic front view showing the overall arrangement configuration of the entrance packing device shown in FIG. 1, FIG. 4 is a vertical sectional view showing an operating state of the entrance packing device shown in FIG. 1, and FIG. FIG. 6 is a vertical sectional view of an entrance packing device showing a second embodiment, FIG. 6 is a vertical sectional view of another embodiment of the present invention showing a modified example of a stopper portion, and FIG. 7 is a modified example of a fixed portion of a check metal fitting. FIG. 8 is a schematic front view of another embodiment of the present invention. 10 ... Entrance packing device, 11 ... Elastic packing member, 12 ... Non-return fitting, 14 ... Fixed part, 15 ... Oscillating plate part, 19 ... Hinge pin, 20, 22, 23 ... Stopper part, 21: Flexible member.

Claims (7)

[Claims] 1. An annular elastic packing member for sealing an annular gap formed in an opening of an entrance of a vertical shaft for starting or reaching a shield excavator,
In a vertical shaft enstras packing device in which a non-return fitting for supporting the back surface of the elastic packing member against external pressure is attached, wherein the non-return fitting is fixed to the elastic packing member and the floor transformer by an anchor transformer. Section, a swing plate section extending from an end portion on the inner side of the entrance transformer opening of the fixed section toward the center of the entrance transformer opening, and connected to the fixed section in a swingable manner, and the swing plate section. And a stopper portion for restricting the swinging range of the swinging plate portion so that the swinging plate portion takes an acute inclined posture with respect to the cross section of the entrance opening when the swinging plate portion is located at the minimum distance from the center of the entrance opening. An entrance packing device characterized in that 2. The entrance packing device according to claim 1, wherein the swing plate portion is swingably connected to the fixed portion via a hinge pin. 3. The entrance packing device according to claim 1, wherein the swing plate portion is swingably connected to the fixed portion via a flexible member. 4. The entrance packing device according to claim 1, wherein the stopper portion is provided on the fixed portion. 5. The entrance packing device according to claim 1, wherein the stopper portion is provided on the swing plate portion. 6. A plurality of said fixing portions are arranged at intervals along the inner circumference of the entrance transformer opening, and said swinging plate portion is swingably connected to each of said fixing portions. The entrance packing device according to 1. 7. The fixed portion extends annularly along the inner circumference of the entrance opening, and each of the plurality of rocking plate portions arranged at intervals along the inner circumference of the entrance opening fixes the fixed portion. The entrance packing device according to claim 1, wherein the entrance packing device is swingably connected to the portion.