JP2022134305A - excavator - Google Patents

Abstract

To provide an excavator that eliminates bitter work using man power and improves efficiency of excavation in performing propulsion burying of a rectangular pipe into the ground.SOLUTION: An excavator 100 comprises: an inner cylindrical body 10 provided inside a front part of a rectangular pipe 40, with a gap therebetween; a main cutter body 20 that is supported by partition walls 14, 15 of the inner cylindrical body 10 and excavates a ground B; a rectangular frame shape body 30 that is fixed to an outer peripheral surface of a front part of the inner cylindrical body 10, is detachably fixed to an inner peripheral surface of a front end part of the rectangular pipe 40, and has a front side plate body 31 surrounding the periphery of the main cutter body 20; and four sub cutter bodies 50 that are supported by the front side plate body 31 and excavate the ground B at four corners of the rectangular pipe 40. A cutter head 51 has a shape eccentric with respect to the center of rotation of the cutter head 51. A maximum passage region of the cutter head 51 partially includes a region exceeding an outer edge of the rectangular pipe 40, and the whole shape of each respective cutter head 51 can be located within the outer edge of the rectangular pipe 40.SELECTED DRAWING: Figure 2

Description

TECHNICAL FIELD The present invention relates to an excavator, and more particularly to an excavator that excavates the ground located in front of a rectangular pipe while propelling the rectangular pipe into the ground.

BACKGROUND ART Conventionally, underpass tunnel construction has been carried out in which tunnels are constructed on the ground below existing railroads, roads, etc. to cross them. At this time, in order to support the upper layer of ground and prevent subsidence of the existing railway and road, prior to the construction of the tunnel body, a plurality of rectangular pipes were arranged horizontally underground to form a roof. It has been practiced to form a support pipe roof. When forming the pipe roof, a propulsion burying method by so-called mechanical excavation is used, in which the rectangular pipe is propelled while rotating the ground located in front of the rectangular pipe with the cutter head of the excavator installed at the front end of each rectangular pipe. may be used.

According to such a propulsion burying method by mechanical excavation, since it does not rely on human power, it is possible to eliminate difficult work and excavate with high efficiency. However, if the space on the rectangular pipe arrival side for recovering the excavator and using it for excavating the next rectangular pipe is not prepared, or if there are obstacles such as gravel in the excavated ground, It has not been widely used because it cannot be recovered from the inside of the pipe to the starting side behind.

On the other hand, when constructing a circular tunnel, the excavator is recovered from the circular tunnel to the rear starting side (see Patent Documents 1 and 2, for example).

Japanese Patent No. 3892412 Japanese Patent No. 4693799

However, in the techniques disclosed in Patent Documents 1 and 2, when excavating a tunnel having a rectangular cross section, an unexcavated portion remains in addition to the central portion where the cutter head rotates and excavates. However, it is necessary to excavate manually using a hand-held excavator or the like, and there is a problem that the merits of mechanical excavation such as elimination of the above-mentioned difficult work and high efficiency of excavation cannot be demonstrated.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an excavator capable of resolving the laborious task of manpower and increasing the efficiency of excavation when pushing and burying a rectangular pipe in the ground. With the goal.

The excavator of the present invention is an excavator that excavates the ground located in front of the rectangular pipe when propelling the rectangular pipe into the ground, wherein the inner portion of the rectangular pipe is positioned inside the front portion of the rectangular pipe. A cylindrical inner cylindrical body provided with a gap between it and the peripheral surface, and a cutter head supported by the partition wall of the inner cylindrical body and rotating the ground positioned in front of the central portion of the rectangular pipe. and a main cutter body for excavating by means of a main cutter body fixed to the outer peripheral surface of the front portion of the inner cylindrical body and detachably fixed to the inner peripheral surface of the front end portion of the rectangular pipe to surround the main cutter body. and four auxiliary cutters supported by the surrounding members of the rectangular frame and positioned in front of the four corners of the rectangular pipe for excavating the ground by rotating cutter heads. The shape of the cutter head of the sub-cutter body in front view is eccentric with respect to the rotation center of the cutter head, and the maximum passage area of the cutter head of the sub-cutter body in front view is the rectangular pipe. It is characterized in that the entire shape of the cutter head of each of the sub-cutter bodies in a front view can be positioned within the outer edge of the rectangular pipe while partially including a region beyond the outer edge.

According to the excavator of the present invention, the cutter head of the main cutter body rotates and excavates the ground located in front of the central portion of the rectangular pipe, and the cutter heads of the four sub-cutter bodies are used to excavate the four corners of the rectangular pipe. Rotary excavation is performed on the ground located in front of the corner. This reduces the amount of ground that workers have to excavate using hand-held excavators, etc., so when pushing and burying rectangular pipes in the ground, it eliminates the laborious task of manpower and improves excavation efficiency. It is possible to plan In addition, since the rectangular frame-shaped body is detachable from the rectangular pipe, the rectangular frame-shaped body, the inner cylindrical body integrated therewith, the main cutter body, and the sub-cutter body can be separated from the rectangular pipe and recovered to the rear. becomes possible.

Further, since the maximum passage area of the cutter head of the sub-cutter body in the front view partially includes the area beyond the outer edge of the rectangular pipe, the maximum passage area of the cutter head of the sub-cutter body in the front view includes the outer edge of the rectangular pipe. Compared to the case where the distance is not exceeded, less excavation remains, the rectangular pipe can be smoothly propelled, and the thrust required for the propulsion can be reduced.

Furthermore, since the entire shape of the cutter head of each sub-cutter body in the front view can be positioned within the outer edge of the rectangular pipe, by locating the cutter head of each sub-cutter body at such a position, It may be possible to move the sub-cutter body together with the rectangular frame-shaped body backward through the rectangular pipe.

In the excavator of the present invention, it is preferable that the inner cylindrical body and the rectangular pipe are detachably connected via a connecting mechanism.

In this case, the main cutter body, the sub-cutter body, the inner cylindrical body and the rectangular frame-like body can be passed through the rectangular pipe and moved backward. Furthermore, the connecting mechanism also functions as a reaction force transmission mechanism that transmits the reaction force acting on rotary excavation of the ground by the cutter heads of the main cutter body and the sub cutter body to the rectangular pipe.

Further, in the excavator of the present invention, the connecting mechanism includes a cylindrical transmission ring detachably provided at the rear portion of the inner cylindrical body, and an inner ring of the rectangular pipe in contact with the rear surface of the transmission ring. It is preferable that it is composed of a reaction force receiving member that is detachably attached to the peripheral surface.

In this case, the transmission ring is a member that is likely to be damaged when the main cutter body, the sub cutter body, the inner cylindrical body, and the rectangular frame-shaped body are pulled out rearward, so damage to the inner cylindrical body can be suppressed. be possible.

Further, in the excavator of the present invention, the rectangular pipe includes a rectangular pipe main body and an outer rectangular pipe provided at the front end of the rectangular pipe main body and having an outer peripheral edge shape substantially the same as the outer peripheral edge shape of the rectangular pipe main body. and a tubular body, and the outer rectangular tubular body preferably forms the front end of the rectangular pipe.

In this case, as the rectangular pipe main body, it is possible to use a conventionally used rectangular pipe that is successively added from the rear.

1 is a schematic front view of an excavator according to an embodiment of the present invention; FIG. FIG. 2 is a schematic cross-sectional view taken along line II-II in FIG. 1; FIG. 3 is a schematic enlarged view of part C in FIG. 2 ; D model enlarged view in FIG. FIG. 5 is a schematic cross-sectional view of the portion shown in FIG. 4 taken along line VV.

An excavator 100 according to an embodiment of the present invention will be described with reference to FIGS. 1 and 2. FIG. For example, the excavator 100 uses a jacking method for propelling a plurality of rectangular pipes 40 arranged horizontally in an underpass construction for constructing a tunnel crossing the ground below an existing railroad, road, or the like. When doing this, the ground B located in front of each rectangular pipe 40 is excavated.

In some cases, a plurality of excavators 100 are arranged side by side in correspondence with each of the rectangular pipes 40 arranged in a horizontal direction. An example will be described.

Further, in the following description, the excavation direction (propulsion direction of the rectangular pipe 40) is the forward direction (left direction in FIG. 1, the front direction of the paper surface in FIG. 1, the left-right direction in FIG. 2). Note that all the drawings are diagrams for schematically explaining the present embodiment, and each constituent member is schematically illustrated, and the dimensions thereof are also deformed.

The excavator 100 excavates the ground B located in front of the rectangular pipe 40 . A rectangular pipe main body 40a, which is the main body of the rectangular pipe 40, is also called an element, and is, for example, a steel hollow pipe member having a substantially square cross-sectional shape of about 800 mm in length and width. Although not shown, the rectangular pipe main body 40a is propelled in the direction of propulsion by being successively replenished from the rear.

The excavator 100 includes an inner cylindrical body 10, a main cutter body 20, a rectangular frame body 30, a rectangular pipe 40, four sub cutter bodies 50, and the like.

The inner cylindrical body 10 is provided inside the front end portion of the rectangular pipe main body 40a, and is made of steel or the like. The inner cylindrical body 10 has a cylindrical shape, a front cylindrical body 11 positioned on the front side, a rear cylindrical body 12 positioned on the rear side, and the front cylindrical body 11 and the rear cylindrical body 12 can be bent freely. It has a connection body 13 connected to the . Although not shown in detail, the connecting body 13 is provided with a sealing material, and is configured such that the front cylindrical body 11 and the rear cylindrical body 12 are in sliding contact with the sealing material therebetween.

Furthermore, the end of the piston and the end of the cylinder of the folding jack 61 are fixed to the front cylindrical body 11 and the rear cylindrical body 12, respectively. The expansion and contraction of the piston of the center-folding jack 61 can change the bending angle between the front cylindrical body 11 and the rear cylindrical body 12 and thus the excavating direction of the excavator 100 .

Further, the outer peripheral surface of a disk-shaped front partition wall 14 is fixed to the inner peripheral surface of the front portion of the front cylindrical body 11 by welding or the like. The outer peripheral surface of a disc-shaped rear partition wall 15 is fixed to the inner peripheral surface of the central portion of the front cylindrical body 11 by welding or the like. Openings are formed in the centers of these partitions 14 and 15, and a motor 21 for rotating the main cutter body 20 is supported by the inner cylindrical body 10 while being inserted through these openings. The main cutter body 20 excavates the center portion of the ground B located in front of the rectangular pipe 40 by rotating the cutter head 22 by the motor 21 .

Openings are also formed in the lower portions of the front partition wall 14 and the rear partition wall 15, and earth and sand excavated by the main cutter body 20 and the sub-cutter body 50 are discharged rearward through these openings. A soil unloading mechanism 62 is supported by the inner cylindrical body 10 for the purpose.

On the other hand, a rectangular frame-like body 30 supporting four sub-cutter bodies 50 is fixed by welding or the like to the outer peripheral surface of the front end portion of the front cylindrical body 11 . The rectangular frame-shaped body 30 includes a front plate 31 positioned on the front side, a rear plate 32 positioned on the rear side, and a connecting plate connecting the front plate 31 and the rear plate 32, each of which is made of a steel plate or the like. A body 33 is fixed by welding or the like.

The front plate 31 has a large circular opening in the center through which the main cutter 20 is inserted, and small circular openings through which the sub-cutter 50 is inserted in the four corners of the opening. there is Thus, the front side plate 31 surrounds the main cutter body 20 and corresponds to the surrounding member of the present invention. The rear plate 32 is provided at four corners corresponding to the four sub-cutter bodies 50, and each has a small circular opening through which the sub-cutter bodies 50 are inserted.

The rectangular pipe 40 is composed of a rectangular pipe body 40a and an outer rectangular cylinder (cutting edge) 40b. The outer rectangular cylinder 40b is made of, for example, steel, is provided at the front end of the rectangular pipe main body 40a, and has substantially the same outer peripheral shape as the rectangular pipe main body 40a when viewed from the front. The outer rectangular cylindrical body 40b is fixed to the rectangular frame-shaped body 30 by a structure described later. As a result, the outer rectangular cylinder 40 b is fixed to the outer peripheral surface of the front end portion of the inner cylindrical body 10 via the rectangular frame-shaped body 30 . Although not shown, the outer rectangular cylinder 40b may have a member for fixing or engaging with the outer rectangular cylinder 40b of the adjacent excavator 100, for example.

The outer rectangular tubular body 40b and the rectangular frame-shaped body 30 are detachably engaged with each other so that no gap is formed between them. Specifically, as shown in FIG. 3, inclined portions 34 are formed on the outer surface of the connecting plate 33 of the rectangular frame 30 at the four corners thereof so as to protrude rearward. It is On the other hand, on the inner peripheral surface of the central portion of the outer rectangular cylinder 40b, inclined portions 41 are formed at positions corresponding to the inclined portions 34 so as to protrude forward.

By engaging these inclined portions 34 and 41, the outer rectangular cylindrical body 40b and the rectangular frame-shaped body 30 are engaged with each other, and the formation of a gap therebetween is prevented. Furthermore, there is a gap between the outer rectangular cylindrical body 40b and the rectangular frame-like body 30 in front of the inclined portions 34 and 41 that are engaged with each other. there is

Further, a locking member 42, here a stopper having a cross section of a right triangle in side view, is fixed by welding or the like to the inner peripheral surface of the front portion of the outer rectangular cylinder 40b. The forward movement of the rectangular frame-shaped body 30 is restricted by abutting the peripheral edge portion of the front side plate 31 of the rectangular frame-shaped body 30 against the locking member 42 . In addition to the locking by the locking member 42, the engagement of the inclined portions 34 and 41 positions and fixes the rectangular frame-like body 30 with respect to the outer rectangular cylinder 40b.

Each of the sub-cutter bodies 50 has a cutter head 51 at its front end and incorporates a motor (not shown) for rotationally driving the cutter head 51 . When viewed from the front, the shape of each cutter head 51 is eccentric with respect to its center of rotation. Specifically, the cutter head 51 has a substantially oval shape when viewed from the front, and is rotationally asymmetric with respect to the center of rotation. The cutter head 51 of the sub-cutter body 50 is positioned forward of the cutter head 22 of the main cutter body 20 .

By rotationally driving the cutter heads 51 of the four sub-cutter bodies 50, the four sub-cutter bodies 50 are positioned around the central portion excavated by the cutter heads 22 of the main cutter bodies 20 of the ground B located in front of the rectangular pipe 40, A portion of the ground B located in front of the four corners of the rectangular pipe 40 is excavated.

The maximum area when the cutter head 51 of the sub-cutter body 50 rotates partially protrudes outward from the outer edge of the rectangular frame-shaped body 40b and thus the rectangular pipe 40 in a front view. The outer edge of this maximum area is preferably located on or outside the outer edge of the corner of the rectangular pipe 40 . Since the cutter head 51 of the sub-cutter body 50 is located forward of the cutter head 22 of the main cutter body 20, these cutter heads 22 and 51 do not interfere with each other. On the other hand, a portion included in the maximum area of the cutter head 51 at the front end of the outer rectangular cylinder 40b is notched to avoid interference.

Further, the sub-cutter body 50 has a proximity sensor (not shown) on its central outer surface. Thereby, it is possible to detect whether or not the long portion with the longest distance from the center of rotation to the tip of the cutter head 51 is positioned on the center side. By using this detection result, if the long portion of the cutter head 51 is maintained at the central position, the auxiliary cutter body 50 does not interfere with the rectangular pipe main body 40a, and the inner cylindrical body 10 and the inner cylindrical body 10 and this can be removed. It becomes possible to pull out the integrated rectangular frame-shaped body 30, the main cutter body 20, and the sub cutter body 50 to the rear.

Further, referring to FIG. 3, a carry-out mechanism 64 having rollers, rollers, etc. is attached to the lower portion of the outer peripheral surface of each of the front cylindrical body 11 and the rear cylindrical body 12 . As such a carry-out mechanism 64, for example, a chill tank equipped with endless rollers is preferable. This facilitates the movement of the inner cylindrical body 10 and the structure integrated therewith when pulling it out rearward.

Further, referring to FIGS. 4 and 5, the rear cylindrical body 12, that is, the inner cylindrical body 10 and the rectangular pipe main body 40a are detachably provided via a connecting mechanism 70. As shown in FIG. The connecting mechanism 70 includes a substantially short cylindrical transmission ring 71 fixed to the rear end portion of the rear cylindrical body 12 using a bolt (not shown) or the like, and a ring 71 welded to the inner peripheral surface of the rectangular pipe main body 40a. It is composed of a reaction force receiving member 73 and the like detachably provided between a fixed member 72 fixed by the .

The reaction force receiving member 73 has a notch 73a corresponding to a corner of the front end of the fixing member 72. With this notch 73a engaged with the corner of the front end of the fixing member 72, the transmission ring is closed. 71 is fixed. The reaction force receiving member 73 further has a projecting portion 73 b corresponding to the U-shaped notch 71 a formed in the transmission ring 71 , and this projecting portion engages with the notch of the transmission ring 71 . In this state, it is fixed by three push bolts 74 that are pressed from three directions.

The connecting mechanism 70 also functions as a reaction force transmission mechanism for transmitting the reaction force acting on rotary excavation of the ground B by the cutter heads 22 and 51 of the main cutter body 20 and the sub-cutter body 50 to the rectangular pipe 40 .

At the rear end of the rear cylindrical body 12, a substantially short cylindrical transmission ring 71 is provided so that the inner cylindrical body 10 and the structure integrated therewith can be easily pulled out rearward. Locking tools 65 such as shackles are fixed to the left and right rear portions of the housing. Although not shown, a hook such as a hook is hooked on the locking member 65, and an operator pulls a rope or the like having the hook at one end toward the rear, thereby integrating the inner cylindrical body 10 and this. It becomes easier to pull out the structure backwards.

Here, the rear cylindrical body 12 and the transmission ring 71 are separate members, and are configured to be detachable. As a result, the transmission ring 71 is a member that is likely to be damaged when the excavator 100 is pulled out rearward, and it is possible to suppress damage to the rear cylindrical body 12 . However, the rear cylindrical body 12 and the transmission ring 71 may be integrated.

According to the excavator 100 described above, the cutter heads 51 of the four sub-cutter bodies 50 as well as the central portion of the ground B located in front of the rectangular pipe 40 that the cutter head 22 of the main cutter body 20 rotates excavates. It is also possible to excavate the portion of the ground B located in front of the four corners of the rectangular pipe 40 to be rotary excavated. Therefore, since the portion of the ground B to be excavated by the worker is reduced, it is possible to eliminate the laborious work of manpower and improve the excavation efficiency in promoting and burying the rectangular pipe 40 in the ground.

Further, the inner cylindrical body 10 is separated from the rectangular pipe 40 by releasing the connection between the transmission ring 71 and the reaction force receiving member 73 by the three push bolts 74 . In this state, the inner cylindrical body 10, the rectangular frame-shaped body 30 integrated therewith, the main cutter body 20, and the sub cutter body 50 can pass through the rectangular pipe 40 and be moved backward. As a result, when there is an obstacle such as a boulder in front of the excavator 100 or when there is no access pit, the inner cylindrical body 10 and the structure integrated therewith can be pulled out rearward. At this time, by setting the cutter head 51 of the sub-cutter body 50 at a position where it does not interfere with the rectangular pipe 40, there is no hindrance in drawing.

It should be noted that the present invention is not limited to the excavator 100 described above, and can be modified as appropriate. For example, in the excavator 100, the specific configuration of each section 10-50 is not limited to what has been described or illustrated.

DESCRIPTION OF SYMBOLS 10... Inner cylinder 11... Front side cylinder 12... Rear side cylinder 13... Connector 14... Front side partition (partition) 15... Rear side partition (partition) 20... Main cutter body 21... Motor 22... Cutter head 30... Rectangular frame-shaped body 31... Front side plate (surrounding member) 32... Rear side plate 33... Connection plate 34... Inclined portion 40... Rectangular pipe 40a... Rectangular pipe main body , 40b... Outer rectangular cylinder 41... Inclined portion 42... Locking member 51... Cutter head 50... Sub-cutter body 61... Folding jack 62... Earth discharging mechanism 63... Water stop plate 64... Carrying-out mechanism 65 Locking tool 70 Connecting mechanism 71 Transmission ring 71a Notch 72 Fixing member 73 Reaction receiving member 73a Notch 73b Protrusion 74 Push Bolt, 100... Excavator, B... Ground.

Claims (4)

An excavator for excavating the ground located in front of the rectangular pipe when propelling the rectangular pipe into the ground,
a cylindrical inner cylindrical body provided inside the front part of the rectangular pipe with a gap between it and the inner peripheral surface of the rectangular pipe;
a main cutter body supported by the partition wall of the inner cylindrical body and excavating the ground located in front of the central portion of the rectangular pipe with a rotating cutter head;
a rectangular frame-shaped body fixed to the outer peripheral surface of the front portion of the inner cylindrical body and detachably fixed to the inner peripheral surface of the front end portion of the rectangular pipe, and having a surrounding member surrounding the periphery of the main cutter body; ,
four sub-cutter bodies supported by the surrounding members of the rectangular frame-shaped body and excavating the ground located in front of the four corners of the rectangular pipe with a rotating cutter head,
The shape of the cutter head of the sub-cutter body when viewed from the front is eccentric with respect to the center of rotation of the cutter head, and the maximum passage area of the cutter head of the sub-cutter body when viewed from the front is an area beyond the outer edge of the rectangular pipe. and wherein the entire shape of the cutter head of each sub-cutter body in front view can be located within the outer edge of the rectangular pipe. 2. The excavator according to claim 1, wherein said inner cylindrical body and said rectangular pipe are detachably connected via a connecting mechanism. The connecting mechanism is
a cylindrical transmission ring detachably provided at the rear portion of the inner cylindrical body;
3. A reaction force receiving member detachably attached to the inner peripheral surface of the rectangular pipe while in contact with the rear surface of the transmission ring. excavator. The rectangular pipe includes a rectangular pipe main body and an outer rectangular cylindrical body provided at the front end of the rectangular pipe main body and having an outer peripheral edge shape substantially the same as the outer peripheral edge shape of the rectangular pipe main body. 4. Excavator according to any one of the preceding claims, characterized in that a cylinder forms the front end of the rectangular pipe.

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