GB2098168A

GB2098168A - Soil transporting vehicle

Info

Publication number: GB2098168A
Application number: GB8114414A
Authority: GB
Original assignee: Okumura Corp
Current assignee: Okumura Corp
Priority date: 1981-05-12
Filing date: 1981-05-12
Publication date: 1982-11-17
Also published as: GB2098168B

Abstract

A soil transporting vehicle 17 is disclosed for transporting soil excavated by a shield digging machine. The vehicle has a cylindrical soil container 16 having an opening 18 for both charging and discharging the container with soil and an opening 31 for discharging only. A soil conveyor 33 is provided in the container 16 for moving soil along the container. A chassis 23 supports the container so that it is rotatable about its axis from a charging position wherein the openings are directed upwards and a discharging position wherein the openings are directed downwards. A motor 27 is provided for rotating the container. <IMAGE>

Description

SPECIFICATION Soil transporting vehicle The present invention relates to a soil transporting vehicle for transporting soils excavated by a shield digging machine (hereinafter simply referred to as a shield machine). Though not limited thereto, the present invention is especially effective for use in relation with the pressurized slurry shield method or pressurized air shield method wherein slurry or air under pressure is introduced into a pressure compartment defined in the shield machine between a cutter head and a diaphragm located behind the cutter head to prevent the flowing of underground water and entrained soils through the slits in the cutter head and around the periphery of the cutter head into the pressure compartment, thus to prevent also the crumbling of the working face (digging face) of the tunnel.

In order to discharge from the pressure compartment the soil excavated by the shield machine (i.e.

by the cutter head of the shield machine) and forced into the pressure compartment through the slits of the cutter head, and to transport thus discharged soils to ground level, it has been proposed in the past to sealingly connect one end of a pressure resistant water tight (in the case of pressurized slurry shield method) or air tight (in the case of pressurized air shield method) soil conveyor to the diaphragm to discharge the excavated soil from the pressure compartment and connect the other end of the soil conveyor to a soil charging opening of a cylindrical pressure resistant soil container of a soil transporting vehicle through an opening and closing valve mounted on the other end of the soil conveyor.

When the excavated soil is to be discharged from the pressure compartment and to be transported to ground level, the other end of the soil conveyor is connected to the soil charging opening of the soil container via the valve. Then the valve is opened and the soil conveyor is driven to charge the excavated soil into the container. After the soil excavated in one excavation operation corresponding to one pipe section of the tunnel has all been charged into the soil container, the soil conveyor is stopped, the valve is closed and disconnected from the soil charging opening. At this time the soil transporting vehicle may move to the starting shaft of the tunnel for discharging the soil contained in the soil container through a discharge opening provided in the bottom portion of the container into a bucket elevator arranged in the starting shaft.

In this type of soil transporting vehicle, in order to effectively distribute the introduced soil axially of the elongate soil container, a soil distribution chain conveyor is arranged in the container. The distribution conveyor is raisably supported and it is raised as the charging of the soil into the container proceeds, to distribute the successively charging soil throughout the soil container.

As described above, the discharging of the soil from the soil container into the bucket elevator is effected through the discharge opening provided in the bottom portion of the soil container. In this connection, it is to be noted that the distribution conveyor does not contribute to force the soil out of the container through the discharge opening since the distribution conveyor is always positioned close to the upper portion of the soil introduced in the soil container to distribute the soil through the container.

Thus, the soil is discharged only by the gravity.

With such discharging by gravity alone, however, clay soils cannot be discharged satisfactorily since such soil, especially when in the lower portion of the container, sticks together in lumps which cannot pass through the discharge opening of the container.

Furthermore, clay soil adheres around the discharge opening and impedes smooth discharge of the soil.

Even sandy soil can stick together under the pressure in the container.

Furthermore, with the above described soil transporting vehicle, the interior of the soil container is under atmospheric pressure when it is connected to the soil conveyor so that the pressure in the pressure compartment is suddenly decreased when the connection is effected, sometimes resulting in crumbling of the working surface of the tunnel.

It is an object of the present invention to provide a new and improved soil transporting vehicle which is able to satisfactorily discharge soil from the soil container of the soil transporting vehicle.

According to the present invention there is provided a soil transporting vehicle for transporting soil excavated by a shield digging machine comprising a cylindrical soil container having one or more openings for charging and discharging soil, soil conveying means arranged in the soil container adjacent to the opening for moving soil in the soil container axially thereof, a chassis for supporting the soil container rotatably about the longitudinal axis thereof, and drive means for rotating the soil container about the said axis between a soil charging position wherein the opening is directed upwardly and a soil discharging position wherein the opening is directed downwardly.

In an embodiment of the present invention, the soil conveying means comprises a pair of reversible screw conveyors extending axially of the soil container and arranged in side by side relation. These screw conveyors are preferably rotated in opposite directions. In a further embodiment of the present invention, the soil conveying means comprises a reversible chain conveyor having a plurality of scoop members spaced along the chain conveyor.

At least when the soil transporting vehicle of the present invention is to be used in relation with the pressurized slurry or air shield method, the soil container is made.pressure resistant so as to withstand the pressure transmitted from the pressure compartment of the shield machine through the soil conveyor when the container is connected to the pressure compartment through the soil conveyor.

Furthermore, at least when the soil transporting vehicle is to be used in relation with the pressurized slurry or air shield method, the soil container, in a preferred embodiment, is provided with an inlet for introducing gas under pressure into the soil container before the charging of soil into the container.

In use of this embodiment, the soil container may be pre-pressurized to a level equal or substantially equal to the pressure in the pressure compartment so that when the soil container is connected to the compartment through the soil conveyor, there will be substantially no pressure decrease produced in the compartment.

The charging and discharging opening may comprise a single opening which is used for both the charging and discharging of soil.

In another embodiment, first and second openings aligned axially of the soil container are provided, the first opening being used for both the charging and discharging of soil into and from the container, and the second opening is used onlyforthe discharging of soil from the container.

In a still further embodiment, first and second openings aligned axially of the soil container are provided, the first opening is used for the charging of soil into the container and the second opening is used only for the discharging of soil from the container.

Alternatively other arrangements of openings for the charging and discharging of soil into and from the soil container may be provided. What is required of the opening or openings is that soil can be charged or discharged into and from the container.

To help understanding of the present invention a specific embodiment and an alternative will now be described with reference to the accompanying drawings, in which: Figure lisa sectional view showing a tunnel under construction by means of the pressurized slurry shield method and also showing a soil transporting vehicle according to the present invention located in the tunnel; Figure 2 is a partially broken away side elevational view of the soil transporting vehicle of Figure 1, which is in its soil charging position; Figure 3 is a cross-sectional view along the line Ill-Ill of Figure 2; Figure 4 is a side elevational view similar to Figure 2 but wherein the vehicle is in its soil discharging position; Figure 5 is a cross-sectional view along the line V V of Figure 4;; Figure 6 is a partial sectional view of another soil transporting vehicle according to the present invention showing the use of a chain conveyor for moving soil in a soil container of the vehicle and Figure 7 is a perspective view of a part of the chain conveyor of Figure 6.

Referring now to the drawings, and more particularly to Figures 1 and 2, a tunnel which is being constructed by the pressurized slurry shield method is illustrated.

In Figures 1 and 2, the reference manual 1 designates a slurry storage tank placed at ground level from which the slurry is fed through a conduit 2 and a pressure regulating valve 3 into a pressure compartment 4 defined in a shield machine 5 between a cutter head 6 and a diaphragm 7 located behind the cutter head 6. The pressurized slurry in the pressure compartment 4 prevents the flowing of under-ground water and entrained soil through the slits in the cutter head 6 and around the periphery of the cutter head 6 into the pressure compartment 4, and thus prevents also crumbling of the working face of the tunnel. The reference numeral 8 designates a pressure resistant water tight soil conveyor having its one end sealingly connected to the diaphragm 7 in communication with the inside ofthe pressure compartment 4.The soil conveyor 8, as shown, comprises a screw conveyor 9 rotatably held in a sheath 10 and rotatively driven by an electric motor 11. To an outlet 12 at the other end of the soil conveyor 8 is sealingly connected an opening and closing valve 13 the outlet side of which, in turn, is connected to an expandable and contractable chute 14 having a flanged coupling 15. When the soil excavated by the shield machine 5 is to be discharged from the pressure compartment 4 and charged into a cylindrical soil container 16 of a soil transporting vehicle 17, the flanged coupling 15 is connected to an opening 18 provided in the wall of the soil container 16 and the valve 13 is opened.

Then the soil conveyor 8 is driven. When the soil excavated in one excavation operation corresponding to one pipe section 19 of the tunnel have been discharged from the pressure compartment 4 and charged into the soil container 16, the soil conveyor 8 is stopped and the flanged coupling 15 is disconnected from the opening 18, and the soil transporting vehicle 17 is moved by means of a tractor 20 to a soil discharging location for discharging the soil contained in the soil container 16 into a bucket elevator 21 arranged in the starting shaft 22. The reference numeral 23 designates a chassis for supporting the soil container 16. This arrangement and operation is already disclosed in Japanese Patent Publication No.21772/75.

In accordance with the present invention, the cylindrical soil container 16 is supported rotatably about its axis on the chassis 23. For this purpose, the chassis 23 comprises at least two supporting frames 24 and 25 arranged adjacent to the opposite axial ends of the soil container 16 and roller means 26 mounted on the respective frames 24 and 25 in contact with the container 16. The soil container 16 is rotatively driven by means of an electric or hydraulic motor 27 mounted on the chassis 23 through a chain 28 spanning a chain wheel 29 secured to the shaft of the motor 27 and another chain wheel 30 fixed to the central portion of one end wall ofthe soil container 16.

The soil container 16 has a soil charging and discharging opening which comprises, in the disclosed embodiment, the above described opening 18 and another opening 31, which is normally closed by a removable lid 32, aligned, axially of the container 16, with the first opening 18. As described hereinafter, the first opening is commonly used for the charging of soil into and discharge of soil from the container 16. The second opening 31 is used only for the discharge of the soil from the container 16.

Soil conveying means 33 is arranged in the soil container 16 adjacent to the openings 18 and 31 for moving soil in the container 16 axially thereof. As shown in Figure 3, the soil conveying means 33 comprises a pair of reversible screw conveyors 34 and 35 arranged in side by side relation and extending axially of the container 16 through substantially entire length thereof. The screw conveyors 34 and 35 are rotatably supported by bearings 36 and 36' arranged in the opposite end portions of the container 16. The bearing 36 is mounted on a partition 48 which defines a chamber 49 sealed against the soil in the container 16, and the other bearing 36' is mounted on the other end wall of the container 16.

The screw conveyors 34 and 35 are rotatively driven in opposite directions as shown by the arrows in Figure 3 by an electric or hydraulic motor 37 secured to the one end wall of the container 16 through a chain 38 spanning a chain wheel 39 secured to the shaft of the motor 37 and chain wheels 40 secured to the shafts of the respective screw conveyors 34 and 35. The chain wheels 39,40 and the chain 39 are arranged in the chamber 49 so that these elements are protected from contamination by the soil. Alternatively, these elements may be arranged outside the container 16. In this case, the partition 48 may be omitted.

The soil container 16 is provided with an inlet 41 for a gas (e.g. air) under pressure and a pressure regulating valve 43 for regulating the pressure in the container 16. The inlet 41 is connected through a coupling 42 and an opening and closing valve 44 to a compressor (not shown in the drawings) carried by the tractor 20.

When the soil is to be charged into the soil container 16 the flanged coupling 15 is sealingly connected to the opening 18 of the container 16.

Then the valve 44 is opened to introduce pressurized gas such as air from the compressor into the container 16 to raise the pressure inside the container 16 to be equal, or substantially equal, to that of the pressure compartment 4. At this time the valve 44 is closed and the inlet 41 is disconnected from the compressor by releasing the coupling 42. Then the valve 13 is opened and the soil conveyor 8 is driven by the motor 11. It will be easily understood that the opening of the valve 13 does not cause substantial pressure variation or decrease in the pressure compartment 4 since the pressure inside the container 16 has already been increased to a level equal or substantially equal to that of the compartment 4.

After the soil excavated in one excavation operation has been charged into the container 16, the soil conveyor 8 is stopped, the valve 13 is closed and the valve 44 is opened to bring the inside of the container 16 to atmospheric pressure. Then the flanged coupling 15 is released to disconnect the opening 18 from the chute 14 and the lid 32 is removed. During the charging of the soil into the container 16, the screw conveyors 34 and 35 are driven to distribute the charged soil throughout the container.

Then the soil transporting vehicle 17, with the soil container 16 charged with soil, is moved to the soil discharge location 45 wherein a belt conveyor 46 is arranged.

When the soil transporting vehicle 17 has arrived at the soil discharge location 45, the motor 27 is energized to rotate the soil container 16 by 180 angular degrees from the soil charging position wherein the openings 18 and 31 are directed upwardly, as shown in Figures 2 and 3, into a soil discharging position wherein the openings are directed downwardly, as shown in Figures 4 and 5.

The rotational direction of the screw conveyors 34 and 35 is repeatedly reversed to loosen and to move the soil to the openings 18 and 31 to discharge the soil therethrough onto the conveyor 46 which conveys the discharged soil to the bucket elevator 21.

During the discharge of the soil onto the conveyor 46, the soil container 16 may be repeatedly oscillated by means of the motor 27 about the axis of the container for a certain angular degrees to promote the discharge of the soil. When the soil in the container 16 has been discharged onto the conveyor 46, the motor 27 is again energized to rotate the container 16 into its soil charging position and the vehicle 17 is returned to the original position for being connected with the soil conveyor 8. The lid 32 is replaced and the inlet 41 is connected to the compressor through the coupling 42.

As will be understood from the above, the soil conveying means 33 becomes located in the bottom portion of the soil container 16 when the latter is rotated into the soil discharging position so that the soils contained in the container 16 are forcedly moved to and discharged through the openings 18 and 31 by the soil conveying means 33. Furthermore, any lumps of soil are broken into smaller pieces by the soil conveying means 33 so that the soils are easily discharged through the openings 18 and 31.

In the disclosed embodiment, the opening 18 serves for both the charging and discharging of soil and the opening 31 only for the discharging. In this case, if desired, the opening 31 may be omitted. In another arrangement the opening 18 may serve only for the charging and the opening 31 only for the discharging. Further, more than two openings may be provided for both the charging and discharging of soil. When an opening for soil discharging alone, such opening may be arranged in an end wall of the soil container adjacent to an end of the soil conveying means 33. What is required for the soil charging and discharging openings is that it is able to charge and discharge soils in the soil charging position and the discharging position, respectively, of the soil container.

The above described soil transporting vehicle may be similarly used in the pressurized air shield method wherein the air under pressure is fed from an air compressor 47, see Figure 1, at ground level to the pressure compartment 4through the conduit 2.

In this case, the sheath 10 of the soil conveyor 8 and the soil container 16 are made airtight. Furthermore, the vehicle may be used in the normal shield method wherein the pressurized slurry or air is not used. in this case, the sheath 10 and the container 16 will not be required to be air or water tight and to be pressure resistant. The gas inlet 41 may be omitted.

Referring now to Figures 6 and 7, an alternative soil conveying means is shown therein. In this embodiment a chain conveyor 50 is used instead of the screw conveyor 34 and 35. The chain conveyor 50 comprises a pair of chains 56 and 57 between which a plurality of scoop members 51 are fixed by suitable means. The chains 56 and 57 are driven by a pair of toothed pulleys 52 arranged at the opposite sides of an electric motor 53 and fixed to the drive shaft thereof. The motor 53 is supported from the soil container 16 by means of a bracket 54 and suitably energized through wire 55 from outside the container 16. Such chain conveyor 50 is also effective like the screw conveyors 34 and 35 to distribute the charged soil in the soil container 16 during the soil charging and to force the soil through the openings 18 and 31 during the soil discharging.

While the principles of the present invention have been described above in connection with specific embodiments, it isto be easily understood that this description is made only by way of example.

For instance, though the soil container 16 has been described as having a capacity for containing the soil excavated in one excavation operation corresponding to one pipe section 19, the capacity of one soil container 16 may be larger than or smaller than this, and also any number of the vehicles 17 may be coupled for being pulled or moved by the tractor 20 as desired or required. The tractor 20, when desired, may be made integral with the chassis 23 of the vehicle.

Claims

1. A soil transporting vehicle for transporting soil excavated by a shield digging machine comprising a cylindrical soil container having one or more openings for charging and discharging soil, soil conveying means arranged in the soil container adjacent to the opening for moving soil in the soil container axially thereof, a chassis for supporting the soil container rotatably about the longitudinal axis thereof, and drive means for rotating the soil container about the said axis between a soil charging position wherein the opening is directed upwardly and a soil discharging position wherein the opening is directed downwardly.

2. A soil transporting vehicle as claimed in claim 1, wherein the soil conveying means comprises a pair of reversible screw conveyors extending axially of the soil container and arranged in side by side relation.

3. A soil transporting vehicle as claimed in claim 2, wherein the pair of screw conveyors are arranged to be rotated in opposite directions.

4. A soil transporting vehicle as claimed in claim 1, wherein the soil conveying means comprises a reversible chain conveyor having a plurality of scoop members spaced along the chain conveyor.

5. A soil transporting vehicle as claimed in any preceding claim, wherein the soil container is pressure resistant.

6. A soil transporting vehicle as claimed in claim 5, wherein the soil container is provided with an inlet for introducing gas under pressure into the soil container.

7. A soil transporting vehicle as claimed in any preceding claim, wherein first and second openings aligned axially of the soil container are provided, the first opening being intended for both the charging and discharging of soil into and from the soil container, and the second opening being intended for discharging only of soil from the soil container.

8. A soil transporting vehicle as claimed in any one of claims 1 to 6, wherein first and second openings aligned axially of the soil container are provided, the first opening being intended for the charging only of soil into the soil container and the second opening being intended for the discharging only of soil from the soil container.

9. A soil transporting vehicle as claimed in claim 1,wherein there is provided a single opening which is intended for both charging and discharging of soil into and from the soil container.

10. A soil transporting vehicle as claimed in any preceding claim, wherein the chassis has at least two frames arranged adjacent to the opposite axial ends of the soil container and roller means mounted on the respective frames in contact with the soil container for rotatably supporting the same.

11. A soil transporting vehicle substantially as hereinbefore described with reference to Figures 1 to 5 or Figures 6 and 7 of the accompanying drawings.