JPH0660559B2 - Excavator with earth and sand pressure adjustment function - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention, when embedding various pipes, such as pipes constituting a cable storage pipe, in the soil by a propulsion method The present invention relates to a tunnel excavator that is used for excavating sediment in front of the traveling direction and discharging the excavated sediment backward.

(Prior Art) Conventionally, in this type of excavator, a screw conveyor, a belt conveyor, or the like was generally used to discharge the excavated earth and sand backward, but in view of downsizing of the device, Recently, for example, as disclosed in Japanese Patent Application No. 62-266285 by the present applicant, it protrudes from one end of the earth and sand chamber located behind the earth and sand transfer means in the excavator body and is connected to the discharge port of the other end. A technique for discharging excavated earth and sand by a earth and sand pumping device configured by a cylinder and a piston slidable in the cylinder has been proposed.

According to such a sediment pumping device, a cylindrical cylinder projects and retains the retained sediment in a space where the sediment is stored behind the sediment chamber, that is, the sediment transfer means, and then the piston is pushed by the piston with a jack or the like. The excavated earth and sand is discharged backward by sliding the inside to push out the earth and sand in the cylinder to the discharge port.

(Problems to be solved by the invention) However, as long as such a configuration is adopted, the excavator itself is propelling while the cylinder holds the sediment in the sediment chamber and connects it to the discharge port, so that the excavator is excavated. Sediment is being sent to the sand chamber one after another. Therefore, the earth and sand that have no other place to go because the discharge port is blocked fills the earth and sand chamber and eventually has a large pressure.

When the pressure in the sediment chamber rises in this way, the pressure accordingly propagates forward and applies pressure from the face face to the ground in front of it, so there is concern that there will be a lack of ground subsidence or uplift, etc. Not preferable.

It is an object of the present invention to solve such a problem and to provide a safer and more efficient excavator that can efficiently pump the excavated earth and sand to the rear.

(Means for Solving the Problem) In order to solve the problem, the present invention provides a shock absorber having an elastic function for adjusting the pressure in the sediment chamber in which the sediment accumulates, to solve the problem. It is intended. Thus, regarding the specific configuration adopted by the present invention, a cylinder that projects from one end of the earth and sand chamber located behind the earth and sand transfer means in the excavator body and is connected to the discharge port of the other end, and the cylinder concerned In the excavator having a sediment pumping device constituted by a slidable piston, a shock absorber having an elastic function of changing the volume of the sediment chamber is provided in the sediment chamber.

Here, the shock absorber having an elastic function includes air, a suspension using a spring, a shock absorber, and the like. As means for changing the volume in the sediment chamber, for example, the back surface of one wall surface of the sediment chamber is supported by a shock absorber having these elastic functions so that it can be projected and retracted, or can be hermetically sealed in the sediment chamber. Alternatively, an appropriate object may be supported by a shock absorber having an elastic function. In this respect, if an air bag in which air is sealed is installed in the earth and sand chamber, the cushioning function and the function of changing the volume of the earth and sand chamber can be obtained at the same time. In order to make the shock absorbing degree of the shock absorber having the elastic function variable, it is only necessary to change the pressure of each of the air and the spring in the suspension and the shock absorber described above, and the elastic coefficient of the spring. In the case of an air bag, the initial pressure of the stored air may be changed.

(Operation) Even if the cylinder passes through the earth and sand chamber and is connected to the discharge port and the excavated earth and sand fills the earth and sand chamber to increase the pressure,
The shock absorber with elastic function contracts and the pressure is absorbed,
Since the volume of the sediment chamber becomes large, the pressure of the sediment does not propagate forward.

Then, when the cylinder retracts from the earth and sand chamber in preparation for the next stroke, and a space is created in the earth and sand chamber, the shock absorber having the elastic function that has been contracted pushes the earth and sand into the space in an attempt to restore it. . Therefore, the earth and sand to be taken in by the cylinder in the next stroke is quickly prepared.

(Example) Hereinafter, the Example of this invention is described. Reference numeral 1 denotes an excavator main body having a substantially tubular outer shape, and a direction correcting cylinder 3 is provided in front of the excavator main body through a bellows seal 2 and the like. The direction correcting cylinder 3 can be appropriately corrected in a so-called "swinging type" by a direction correcting jack 5 supported by a transfer pipe 4 or the like installed in the excavator body 1. At the center of the excavator body 1, a stirring shaft 7 having a paddle 6 as a stirring protrusion on the outer periphery is provided.
Is rotatably held, and the rear end of the agitation shaft 7 penetrates the partition wall 8 behind the excavator and is installed in the excavator body 1 behind the partition wall 8 to provide a drive device 9 such as a mortar. And the universal joint 10 are interlockingly connected.

On the other hand, a cutter member 12 protruding from a chamber 11 located in the direction correcting cylinder 3 is fixed to the tip of the stirring shaft 7. When the drive device 9 is operated, the stirring shaft 7 rotates,
Along with that, the cutter member 12 simultaneously rotates. Note that the slurry agent discharge hole 13 is located in front of the cutter member 12 and is configured to discharge the slurry agent sent from the inside of the starting side pit. Further, it is the rotation supporting member 14 that rotatably holds the vicinity of the tip of the stirring shaft 7 in the chamber 11, and the stirring blade 15 is fixed to the stirring shaft 7 immediately behind it. The stirring blades 15 are effective in scraping the earth and sand adhering to the inner wall of the chamber 11 to make the earth and sand transfer smooth, and by kneading the earth and sand in the chamber 11 to make the earth and sand properties suitable for the transfer.

The space between the rear end of the transfer pipe 4 and the partition wall 8 forms a sand chamber 16. In the lower space of the transfer pipe 4, a sediment pressure pump, which is a sediment pressure device, is installed.
This earth and sand pressure pump is a cylindrical cylinder 17 slidable into the earth and sand chamber 16, and a piston supported by an appropriate hydraulic jack so as to be slidable inside the cylinder 17.
The cylinder 17 is connectable to the discharge port 19a of the earth and sand pressure-feeding pipe 19 which is composed of 18 and which extends from the lower part of the partition wall 8 to the rear.

An airbag 20 is attached above the sand chamber 16. As shown in FIG. 2, the airbag 20 according to the present embodiment includes a top plate 20a on the side of the earth and sand chamber 16 and a substantially bellows-shaped closed contraction portion 20b made of a rubber material fixed to the top plate 20a. ,
The upper part of the contraction part 20b is constituted by a substrate 20c which is fixed to the inner wall of the excavator main body 1, and air is sealed inside the contraction part 20b. Therefore, when a pressure higher than the air pressure of the air in the contracting portion 20b is applied to the top plate 20a, the contracting portion 20b contracts in the arrow direction in FIG.

The present embodiment is configured as described above. To explain the working condition thereof, the excavator main body 1 is operated from the vertical shaft by a separately provided jack (not shown) while operating the drive device 9. When propelled inside, the cutter member 12 rotates while discharging the slurry agent from the slurry discharge hole 13 to cut the ground in front, and the earth and sand generated thereby are sufficiently mixed by the paddle 6 of the stirring shaft 7. As the excavator body 1 advances, the excavator body 1 is transferred to the rear sediment chamber 16.

Then, these sediments that have reached the sediment chamber 16 are accumulated from the bottom of the sediment chamber 16 in order, so if the cylinder 17 is slid at this stage, the accumulated sediment is taken into the cylinder 17 and the pipes for conveying sediment are sent. It is connected to the discharge port 19a of 19.
Then, the piston 18 is pushed out, and the taken-in earth and sand is pushed out into the earth and sand pressure-feeding pipe 19 and discharged rearward.

During the earth and sand discharging operation, the excavator body 1 is propelled even while the cylinder 17 seals the earth and sand, and the excavated earth and sand are successively sent to the earth and sand chamber 16 to fill the earth and sand chamber 16, Although it has a high pressure, the air bag 20 absorbs the pressure of the earth and sand and contracts, so that the pressure does not propagate forward.

Then, when the pumping of the earth and sand in the cylinder 17 is completed and the cylinder 17 retracts to the lower part of the transfer pipe 4 in order to take in the earth and sand again, the portion occupied by the cylinder 17 until now becomes a space, so Inflow into space. At this time, the airbag 20 which has been contracted pushes down the earth and sand in an attempt to return it to its original state. Therefore, the earth and sand are efficiently pushed into the space where the cylinder 17 slides, and the next stroke can be performed quickly.

(Effect of the Invention) According to the present invention, the fluctuation of the pressure in the earth and sand chamber is suppressed, so that the pressure fluctuation of the cutter unit is suppressed, an excessive burden is prevented from being applied, and smooth cutting is possible.

Moreover, adverse effects on the ground are prevented, and unexpected situations such as ground subsidence and ground uplift are prevented, and excavation work can be performed safely.

Moreover, the restoring function of the shock absorber having an elastic function will push the sediment in the sediment chamber when the shock absorber tries to return to its original state, so when the cylinder is retracted from the sediment chamber, it is occupied by the cylinder until now. Since the sand and sand are pushed into the open space, the suction of the sand and sand is improved, the pumping efficiency is improved, and the rapid excavation work can be performed.

Further, by appropriately adjusting the cushioning degree of the cushioning machine having an elastic function according to the nature of the ground, the pressure applied to the cutter portion can always be maintained within an appropriate range.

[Brief description of drawings]

FIG. 1 is a partial sectional side view of the embodiment, and FIG. 2 is a sectional view taken along the line AA in FIG. In the figure, 1 is the machine body, 6 is the paddle, 7 is the stirring shaft,
Reference numeral 8 is a partition wall, 9 is a drive device, 12 is a cutter member, 16 is a sand chamber, 17 is a cylinder, 18 is a piston, 19 is a pipe for feeding earth and sand, and 20 is an airbag.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hideyo Mogi 1-3-1, Uchisaiwaicho, Chiyoda-ku, Tokyo Inside Tokyo Electric Power Co., Inc. (56) Reference JP-A-61-282598 (JP, A) JP-A-SHO 61-40995 (JP, A) JP 61-45093 (JP, A) JP 61-211499 (JP, A)

Claims (3)

[Claims] 1. A cylinder, which projects from one end of a sediment chamber located behind the sediment transporting means in the excavator body and is connected to a discharge port at the other end, and a piston slidable in the cylinder. An excavator having a sediment pressure adjusting device, characterized in that a shock absorber having an elastic function of changing the volume in the sediment chamber is provided in the sediment chamber. 2. The excavator with a sediment pressure adjusting function according to claim 1, wherein the shock absorber having an elastic function is an airbag. 3. The excavator having a sediment pressure adjusting function according to claim 1 or 2, wherein a shock absorbing degree of the shock absorbing machine having an elastic function is variable.