Patent Application
20050247490
This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2004-137704 filed on May 6, 2004; the entire contents of which are incorporated herein by reference.
The invention relates to a cutting edge apparatus used for tunnel excavation, and in particular to a cutting edge apparatus which facilitates driving of a cutting edge into a ground.
Conventionally, excavation for a tunnel with a relatively small diameter (a diameter up to about several meters) has been performed by workers' hand drilling. In this case, the cutting edge positioned at the distal end of a Hume pipe is propelled by a propelling apparatus such as a hydraulic jack to be driven into the ground. Workers drill the ground and remove soil produced from the cutting face of a tunnel to excavate a tunnel.
In the tunnel excavation, the cutting face may collapse. The collapse causes a large amount of soil to enter the cutting edge, thereby risking workers' safety and rendering working in front of the cutting edge difficult.
A cutting edge apparatus that ensures safe tunnel excavation even when there is a risk, such as collapse of a cutting face, has been proposed (see Japanese Patent Application Laid-open No. 2002-242584, for example).
In the cutting edge apparatus, the cylindrical outer pipe has a cutting edge to be driven into the ground at the distal end thereof. The outer pipe has a tapered conical main unit vibrated by a vibration motor therein. When the cutting face of the tunnel collapses, deposition of soil in the conical main unit allows for safe tunnel excavation, which is considerably effective for safety ensuring.
In the above structure, vibrations of the conical main unit caused by the vibration motor reduce friction between the conical main unit and fallen soil, thus easily correcting propelling and directionality of the cutting edge apparatus.
Furthermore, the cutting edge and the conical main unit are provided separately from each other for easy replacement of a worn cutting edge.
In the above structure, however, driving of the cutting edge into a firm ground requires a large force, and the structure should be further improved.
The aspect of the invention provides a cutting edge apparatus. The apparatus includes a cylindrical outer pipe to be driven into a ground. The apparatus includes a vibratable vibration cylinder provided within the outer pipe and being movable relative to the outer pipe in an axial direction of the outer pipe. The apparatus includes a cutting edge member substantially identical in outer size with the outer pipe and being integrally mounted to the outer circumference of the end of the vibration cylinder. The apparatus includes a vibrator mounted to the vibration cylinder and configured to vibrate the vibration cylinder. The vibration cylinder has a tapered rear portion so that the rear portion becomes smaller in size as the rear portion extends toward the rear end of the vibration cylinder.
The cutting edge member may have a distal end coated with a hard material.
The cutting edge apparatus may include a lubrication supplier configured to supply a lubricant to the outer pipe or the outer circumferential surface of a following pipe provided at the back of the outer pipe.
The cutting edge member may be fixed to the outer circumference of the end of the vibration cylinder.
The invention allows for excavation of a tunnel, vibrating the cutting edge member. This way facilitates driving of the cutting edge member into a ground. This way allows the tapered portion of the cutting edge member to receive the fallen soil during falling of the cutting face of the tunnel, thus ensuring safety.
With reference to
In more detail, the vibration cylinder 7 includes an inner pipe 11 supported within the outer cylinder 5 via an annular sealing member 9 to be movable in an axial direction and be capable of vibrating. The front end of the inner pipe 11 is integrally welded to a stopper ring 13. The stopper ring 13 abuts against a stopper 15 provided on the inner face of the outer pipe 5 to restrict the vibration cylinder 7 to movement in a forward direction (the left direction in
The front end of the stopper ring 13 is integrally fixed, by welding or the like, to the rear end of a taper ring 17 whose diameter gradually increases toward the front end thereof. The outer periphery of the front end of the taper ring 17 is integrally welded to a guide ring 19 with an outer diameter slightly smaller than the inner diameter of the outer pipe 5. The guide ring 19 has an outer peripheral face projecting from the front end face (the left end face in
That is, when the propelling apparatus pushes against the outer pipe 5 in a forward direction, the front end face of the outer pipe 5 and the rear end face of the cutting edge member 21 abut against each other to drive the cutting edge member 21 into the ground 3. The step portion between the taper ring 17 and the guide ring 19 and the step portion between the guide ring 19 and the cutting edge member 21 are welded in a taper shape. The taper shape eliminates the step portion to allow for smooth driving of the cutting edge member 21 into the ground. The annular front end face of the cutting edge member 21 is coated with an appropriate hard material 23 having excellent wear resistance and impact resistance, such as alloy tool steel, high-speed steel, or hard metal by spraying.
The structure allows tunnel excavation even if the ground 3 is firm, and achieves a long life of the cutting edge member 21.
The rear portion of the inner pipe 11 gradually decreases in diameter toward the rear end. The rear portion of the inner pipe 11 is integrally welded to a taper body 25. The taper body 25 with a tapered cylindrical shape has a circular opening portion 25a at the rear end portion, and the area of the opening portion 25a is about a fourth (ΒΌ) of a circular area surrounded by the cutting edge member 21. The opening portion 25a with a small diameter of the taper body 25 is attached with a lid 29 to be openable and closable using a hinge 27 (see
The taper body 25 is vibratably supported to the outer pipe 5 by elastic members 33 such as rubbers provided at a plurality of portions on the inner peripheral face on the outer cylinder 5. The taper body 25 is mounted with vibrators 35 such as vibration motors, which applies vibrations to the taper body 25. The outer peripheral face of the taper body 25 has an abutting member 39 fixed thereon. The rear end portion of the abutting member 39 is abutable against the front face of a ring-like bracket 37 provided on the inner peripheral face of the outer pipe 5.
A clearance 38 between the bracket 37 and the abutting member 39 is set to be approximately equal to a clearance 20 between the front end face of the outer pipe 5 and the rear end face of the cutting edge member 21. When the outer pipe 5 and the cutting edge member 21 abut against each other to push forward (propel) the cutting edge member 21, the bracket 37 abuts against the abutting member 39 to push forward the taper body 25. That is, the cutting edge member 21 and the taper body 25 are integrally pushed forward in synchronization with each other. The structure disperses portions being pushed, while the cutting edge member 21 is being pushed forward by the outer pipe 5, thereby suppressing stress.
The rear end of the outer pipe 5 has a following pipe 41 for propelling (pushing forward) the outer pipe 5. In detail, the outer diameter of the following pipe 41 is slightly smaller than an outer diameter of the outer pipe 5. The front end portion of the following pipe 41 abuts against an annular abutting member 43 provided on the inner peripheral face of the outer pipe 5 near the rear end thereof. The outer peripheral face of the distal end portion of the following pipe 41 and the inner peripheral face of the outer pipe 5 have an annular sealing member 45 made from rubber mounted therebetween.
The inner peripheral face of the following pipe 41 near the rear end has an annular distal end face abutting member 49 to be pushed forward by the distal end face of the Hume pipe 47. The annular chamber 51 is formed at the front side (the left side in
The outer peripheral face of the following pipe 41 has an annular opening member 63 corresponding to the chamber 51. The opening member 63 is provided with opening portions 61 (see
When lubricant such as oil is properly supplied from the supplying ports 53 into the chamber 51, lubricant in the chamber 51 is supplied to the opening portions 61 so that lubricant is supplied on the outer peripheral face of the Hume pipe 47 through the opening portions 61. Thereby, while the Hume pipe 47 is being pushed forward by a propelling apparatus such as a hydraulic jack, friction between the Hume pipe 47 and the ground 3 is made small, thereby facilitating pushing of the Hume pipe 47. The condition of the lubricant in the chamber 51 is confirmed through the inspection port 59. When, for example, lubricant has been consolidated, detachment of the lid member 57 permits the lubricant to be easily taken out of the chamber 51.
In the structure, when the propelling apparatus pushes forward against the Hume pipe 47, the Hume pipe 47 pushes against the following pipe 41 and the following pipe 41 pushes against the outer pipe 5. When the outer pipe 5 is pushed forward, the distal end face (the front end face) of the outer pipe 5 abuts against the cutting edge member 21 to be pushed forward, thus driving the cutting edge member 21 into the ground 3.
During the driving-into, when the vibrators 35 are driven to vibrate the taper body 25, integral provision of the taper body 25 and the cutting edge member 21 allows integral vibrations thereof. Thereby, the cutting edge member 21 is driven while being vibrated to the ground 3. Even if the ground 3 is firm, effective driving is allowed to improve efficiency.
When the cutting edge member 21 is driven into the ground 3, the lid 29 is held in a closed state thereof, considering collapse of a cutting face of the ground 3. After the cutting edge member 21 is driven into the ground 3, the lid 29 is opened. The cutting edge member 21 then excavates the cutting face of the ground 3 in a surrounded state, thus excavating a tunnel.
After soil produced by excavation is ejected from the taper body 25, the propelling apparatus drives the cutting edge member 21 into the ground 3 again. Repetition of this work continuously performs tunnel excavation.
As understood from the descriptions, the taper body 25 and the cutting edge member 21 integrally provided vibrate integrally. This vibration facilitates driving of the cutting edge member 21 into the firm ground 3 as compared with the conventional system. When a large amount of fallen soil is present inside the taper body 25, the vibration reduces friction between fallen soil and the taper body 25, thus facilitating directional correction of the cutting edge member 21.
The coating of the hard material 23 on the distal end portion of the cutting edge member 21 enhances wear resistance and impact resistance, thereby, allowing for the long life in the cutting edge member 21.
Further, the following pipe 41 has the lubricant supplying ports which supply lubricant to the outer peripheral face of the Hume pipe 47, thus reducing friction occurring during pushing of the Hume pipe 47 forward.
The structure is applied to the outer pipe 5, and the lubricant supplying ports may be provided in the outer pipe 5.
With reference to
The excavation facilities 100 include a cutting edge apparatus 1 which excavates the ground 3. The excavation facilities 100 include a jacking pipe 101 serving as a Hume pipe 47 communicating with the cutting edge apparatus 1. The end of the jacking pipe 101 projects above the pit floor 121 within a pit 113. The excavation facilities 100 include a battery feeder 103 feeding power to the vibrators 35. The excavation facilities 100 include a compressed air-mixer 105 and a flexible pipe 107 connected to the compressed air-mixer 105 in the jacking pipe 101. The excavation facilities 100 include a vacuum pump 109 connected to the flexible pipe 107. Soil produced by excavation is conveyed by a truck 111.
The excavation facilities 100 include an adapter 123 mounted at the end of the jacking pipe 101 in the pit 113. The excavation facilities 100 include a reaction wall 125 provided on the side wall of the pit 113. The excavation facilities 100 include jacking cylinders 127a and 127b serving as a propelling apparatus arranged between the reaction wall 125 and the adapter 123.
The excavation facilities 100 include a generator 131 and a power pack 133 for supplying power to the battery feeder 103. The excavation facilities 100 include, outside the pit 113, a lubrication pump 135 serving as a lubricant supplying section, which supplies lubricant to the jacking pipe 101. A hydraulic crane 137 which conveys, for example, jacking pipes 101, is put on standby outside the pit 113.
A method of operating the excavation facilities 100 will be described.
When the jacking cylinders 127a and 127b push against the jacking pipe 101 forward, the jacking pipe 101 pushes against the outer pipe 5 of the cutting edge apparatus 1 to drive the cutting edge member 21 into the ground 3. During the driving-into, the lubrication pump 135 supplies lubricant to the outer face of the jacking pipe 101.
The generator 131 supplies power to the vibrators 35 via the battery pack 133 and the battery feeder 103. The vibrators 35 vibrate the cutting edge member 21 as well as the vibration cylinder 7. The cutting edge member 21 excavates a tunnel in the ground 3.
Soil produced by excavation is sucked up on a ground via the flexible pipe 107 by the vacuum pump 109, and it is loaded on the truck 111.
When the cutting edge apparatus 1 goes into the ground 3 at a fixed distance, a new jacking pipe is hung down in the pit 113 by the hydraulic crane 137. The new jacking pipe is set to the end of the jacking pipe 101 in use.
Although the invention has been described above by reference to certain embodiments of the invention, the invention is not limited to the embodiments described above. Modifications and variations of the embodiments described above will occur to those skilled in the art, in light of the above teachings. The scope of the invention is defined with reference to the following claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| P2004-137704 | May 2004 | JP | national |
