JP2005133367A - Multishaft type ground excavation device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a multishaft type ground excavation device of excellent durability prevented from the wear of an excavating rod or the like even under long-term operation in the multishaft type ground excavation device provided with a plurality of excavating rods and an excavating rod connecting member for connecting the plurality of excavating rods to each other to keep the excavating rods parallel. <P>SOLUTION: This multishaft type excavation device 1 has the excavating rods 2, 3 held parallel through the excavating rod connecting member 8. The excavating rods 2, 3 have a plurality of strip protrusion bodies 32 formed of a wear-resistant alloy, on the outer peripheral surface brought into sliding contact with grip parts 20, 21 of the excavating rod connecting member 8. A plurality of strip protrusion bodies 36 formed of the wear-resistant alloy are formed also on the inner peripheral surfaces of the grip parts 20, 21 of the excavating rod connecting member 8. It is preferable that the extending direction of the strip protrusion bodies 32 of the excavating rods 2, 3 almost perpendicularly intersects the extending direction of the strip protrusion bodies 36 of the excavating rod connecting member 8. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a multi-axis type ground excavator used for ground improvement work or the like.

As a ground excavator, a drilling rod extending in the vertical direction provided with a head for excavation, a stirring blade extending in the horizontal direction fixed to the drilling rod, and a horizontal direction rotatably attached to the drilling rod It is known to have a co-rotation preventing wing extending in the direction.
Even if the excavation rod rotates and digs downward while the excavation rod rotates, the co-rotation prevention wing does not rotate with the excavation rod. On both sides, gradually wear out.
In order to eliminate such an inconvenience, it has been proposed to provide a weld overlay on the outer periphery of the excavation rod that is in sliding contact with the co-rotation preventing blade. In addition, it has also been proposed to provide a build-up by welding on the surface on the side of the co-rotation preventing wing of the flange that restrains the vertical movement of the co-rotation preventing wing (see Patent Document 1).
Japanese Patent No. 3088981

In recent years, in order to improve the efficiency of ground improvement work, a multi-axis type ground excavation device having a plurality of excavation rods is often used.
The multi-axis type ground excavator is configured to arrange a plurality of excavation rods in parallel via excavation rod connecting members and excavate these plural excavation rods at the same time. The excavation area per one excavation operation is reduced. By increasing the size, the working time can be shortened.
However, since the multi-axis type ground excavator generates friction on the sliding contact surface between the rotating excavating rods and the excavating rod connecting member whose position is fixed without rotating, it prevents co-rotation with the excavating rod described above. Similar to the problem related to the blade, there is a problem that the excavation rod and the excavation rod connecting member are worn and the durability is lowered.
In particular, when the excavation rod wears and the excavation rod needs to be repaired or replaced, the excavation rod is long, and since the excavation rod is equipped with a large number of members such as stirring blades, Not only does the repair and replacement of the excavation rod require a lot of work, but there are also inconveniences such as the operation of the multi-axis type ground excavation device being forced to stop for a long time.

These problems are particularly prominent in the multi-axis type ground excavator than the single-axis type ground excavator. This is because, in a multi-axis ground excavator, even if only one of a plurality of excavating rods hits a cobblestone or a concrete piece, the excavating rods are connected to each other. This is because a load is exerted on other drill rods and drill rod connecting members which are not, and adverse effects are exerted.
Therefore, the present invention is a multi-axis ground excavation apparatus comprising a plurality of excavation rods and an excavation rod connecting member for connecting the plural excavation rods and keeping the excavation rods parallel to each other. An object of the present invention is to provide a multi-axis type ground excavating apparatus excellent in durability in which a drilling rod or the like does not wear even if operated for a period of time.

As a result of intensive studies to solve the above problems, the present inventor has provided a wear-resistant projection on the outer peripheral surface of the excavating rod that is in sliding contact with the excavating rod connecting member, so that a multiaxial ground including the excavating rod is provided. The present inventors have found that the main part of the excavator can be operated in a good condition without performing replacement work for a long time.
That is, the multi-axis ground excavation device of the present invention (Claim 1) is for connecting a plurality of excavation rods arranged in parallel to each other and the plural excavation rods to keep the excavation rods in parallel. A multi-axis type ground excavation apparatus comprising one or more excavation rod coupling members, wherein the excavation rod coupling member has a plurality of gripping portions for gripping the plurality of excavation rods rotatably. Each of the plurality of excavation rods has a wear-resistant protrusion on an outer peripheral surface that is in sliding contact with the grip portion of the excavation rod connecting member.

The multi-axis ground excavation device of the present invention can be configured such that the grip portion of the excavation rod connecting member has a wear-resistant projection on a sliding contact surface with the excavation rod ( Claim 2).
As an example of a preferred embodiment of the multi-axis type ground excavation apparatus configured as described above, the wear-resistant protrusion of the excavation rod and the wear-resistant protrusion of the excavation rod connecting member are 45 in each of which a plurality of strip-like protrusions extending in parallel with each other, the direction in which the belt-like protrusion of the excavation rod extends, and the direction in which the band-like projection of the excavation rod connecting member extends are 45. One that intersects at an angle of ˜90 degrees to reduce the contact area between the belt-like projections (Claim 3).
In the multi-axis ground excavation device of the present invention, the excavation rod has a pair of flanges for sandwiching and supporting the grip portion of the excavation rod connecting member from both sides in the axial direction of the excavation rod, and Each of the pair of flanges is configured to have a wear-resistant member (for example, a molded body made of a wear-resistant cemented carbide) that forms part of the sliding contact surface with the grip portion. (Claim 4).
In the multi-axis ground excavation device according to the present invention, the wear-resistant protrusion on the outer peripheral surface of the excavation rod that is in sliding contact with the gripping portion of the excavation rod connecting member is preliminarily attached to the wear-resistant superalloy member. It is constructed so that it is formed by machining a flat steel made by a manufacturer that is built up, and is formed by fitting and welding in a groove drilled in advance on the outer peripheral surface of the excavation rod. (Claim 5).

The multi-axis ground excavation apparatus of the present invention has a plurality of strip-shaped protrusions made of, for example, a wear-resistant alloy on the outer peripheral surface of the excavating rod that is in sliding contact with the excavating rod connecting member, so that it is difficult to repair or replace it. The excavation rod is not worn and can be stably operated in a good state for a long time.
Further, in the multi-axis ground excavator of the present invention, if the wear-resistant projections are formed not only on the excavation rod side but also on the excavation rod connection member side, the excavation rod and the excavation rod connection member In any case, no wear occurs, so that maintenance work can be further reduced.

In this case, for example, the wear-resistant projections of the excavation rod are formed over the entire outer peripheral surface of the excavation rod in the form of a plurality of strip-like projections parallel to the axial direction of the excavation rod, and excavation The excavation rod connecting member in the form of a plurality of band-like protrusions such that the wear-resistant protrusions of the rod connecting member intersect at an angle of 45 to 90 degrees with respect to the extending direction of the band-like protrusions of the excavating rod. If the entire inner peripheral surface is formed, the portions where the excavation rod and the excavation rod connecting member are in slidable contact are scattered in the form of lattice points, and the total area of these slidable contact portions is reduced. The frictional force between the rod connecting members is reduced, and the rotation state of the excavation rod can be made better and stable.
Further, in the multi-axis ground excavator of the present invention, a part of the surface of the flange on the excavating rod for supporting the excavating rod connecting member on the side of the excavating rod connecting member can be formed of a wear-resistant member. Thus, it is possible to prevent the surface of the flange on the side of the excavation rod connecting member from being worn, and as a result, it is possible to prevent the excavation rod connecting member from rattling and the excavation rod from being shaken.
Further, in the multi-axis ground excavation device of the present invention, the wear-resistant superalloy member is previously built as an abrasion-resistant protrusion on the outer peripheral surface of the drill rod that is in sliding contact with the gripping portion of the drill rod connecting member. If you use a flat steel made by the manufacturer and fit and weld a groove drilled in advance on the outer peripheral surface of the drilling rod, the superalloy member will not fuse with the steel of the drilling rod, Compared with the case where the wear-resistant superalloy member is directly welded on the outer peripheral surface of the excavation rod, the wear resistance can be further improved.

The multi-axis ground excavation apparatus of the present invention will be described below with reference to the drawings.
FIG. 1 is a front view showing an example of a multi-axis ground excavation device according to the present invention, and FIG. 2 is an enlarged view showing a connection structure between a drill rod and a drill rod connecting member in the multi-axis ground excavation device shown in FIG. FIG. 3 is a cross-sectional view showing a state cut along line AA in FIG. 2, and FIG. 4 is a front view showing a half-shaped member constituting a gripping portion of the excavation rod connecting member shown in FIG. 5 is a front view showing the structure of the excavation rod in a state where the excavation rod connecting member is removed from the connection structure shown in FIG. 2, and FIG. 6 is a diagram showing the structure of the excavation rod shown in FIG. It is a longitudinal cross-sectional view which shows the state cut | disconnected by the vertical plane which passes.

The multi-axis type ground excavation apparatus of the present invention is used by being mounted on a traveling vehicle (base machine) in the ground improvement work for creating a soil cement column or the like.
As shown in FIG. 1, the multi-axis type ground excavation apparatus 1 of the present invention includes two excavation rods 2 and 3 arranged in parallel via excavation rod connecting members 8. In the present invention, the number of excavation rods may be three or more.
The excavation rod 2 includes an excavation head 4, an excavation blade 6, a gripping portion 20 of the excavation rod connecting member 8, annular flanges 23 and 24, joint rotation prevention blades 9, annular flanges 16 and 17, stirring blades 11 and 13, and the like. Is attached.
Among these, the excavation head 4 is a conical member fixed to the lower end of the excavation rod 2.
The excavation blade 6 is formed as two rod-like bodies extending horizontally from the excavation rod 2 in opposite directions. The excavation rod 2 is provided with a solidified material discharge hole in the shaft near the joint portion with the excavating blade 6, and a solidified material such as cement milk is discharged from the solidified material discharge hole. . The excavation blade 6 is fixed to the excavation rod 2, rotates with the rotation of the excavation rod 2, and excavates the ground with a plurality of excavation claws 15 within the rotation radius.

The flanges 23 and 24 are mounted as a pair of annular bodies fixed on the excavation rod 2 at a predetermined interval in the vertical direction. The flanges 23 and 24 are for supporting the grip 20 of the excavation rod connecting member 8.
The co-rotation prevention wing 9 is formed as two rod-like bodies extending horizontally from the excavation rod 2 in opposite directions, and the vertical movement is restrained by the annular flanges 16 and 17 fixed on the excavation rod 2. In this state, it is rotatably mounted on the excavation rod 2. Even if the excavation rod 2 digs downward while rotating, the co-rotation preventing wing 9 moves downward while maintaining the same posture without rotating, so that the excavated soil can be prevented from co-rotating. . In other words, when the excavating blade 6 advances downward, the soil excavated by the excavating blade 6 tends to rotate together with the excavating blade 6. 9 to stop the stirring and mixing of the soil and the solidified material.
The agitating blades 11 and 13 are each formed as two rod-like bodies fixed to the excavating rod 2 and extending horizontally from the excavating rod 2 in the opposite directions to each other. It is for stirring and mixing.

On the other hand, similarly to the excavation rod 2, the excavation rod 3 also includes the head 5, the excavation blade 7, the gripping portion 21 of the excavation rod connecting member 8, the annular flanges 23 and 24, the co-rotation prevention wing 10, the annular flange 18, 19, stirring blades 12, 14 and the like are attached. However, the excavating blades 7 and the like of the excavating rod 3 are mounted with their positions shifted from the excavating blades 6 and the like so as not to collide with the excavating blades 6 and the like of the excavating rod 2.
As shown in FIGS. 1 to 6, the excavation rod connecting member 8 that connects the excavation rods 2 and 3 includes a grip portion 20 interposed between the flanges 23 and 24 and a grip interposed between the flanges 25 and 26. It is comprised from the part 21, and the connecting rod 22 which connects the holding part 20 and the holding part 21. As shown in FIG.
Among these, as shown in FIG.3 and FIG.4, the holding | grip part 20 is formed in the substantially cylindrical shape by which the substantially half-cylindrical half-shaped members 30 and 31 were combined facing.

  Here, as shown in FIG. 4, the half member 30 includes a semi-cylindrical curved portion 33, a flat plate portion 34 extending outward from one linear edge of the curved portion 33, and the curved portion 33. The flat plate portion 35 extends outward from the other straight edge. The flat plate portions 34 and 35 of the halved member 30 are provided with a plurality of fixing tool insertion holes 37 for inserting fixing tools such as bolts, and the halved member 30 and the halved member 31 are connected to each other. The gripper 20 can be completed by inserting and attaching the fixing tools 27 and 28 to the fixing tool insertion hole 37 in a combined state.

A plurality of strip-shaped (semi-annular) wear-resistant projections 36 that are curved and extend in the circumferential direction are formed on the inner peripheral surface of the curved portion 33 of the half-shaped member 30.
The protrusion 36 may be formed, for example, as a build-up using a welding rod or the like, or may be formed by fitting a semi-annular wear-resistant cemented carbide member.
Here, the material of the build-up forming the protrusions 36 may be any material as long as the protrusions 36 do not wear out in a short period of time due to sliding contact with the excavation rod 2. Although not particularly limited, it is desirable to avoid the use of a material having a hardness higher than that of the protrusion 32 in order to prevent the protrusion 32 (see FIG. 5) on the excavation rod 2 from being worn. Examples of the material of the wear resistant cemented carbide member include tungsten carbide alloy, high chromium wear resistant cast iron, and high manganese wear resistant cast iron.
The half member 31 that is the other member constituting the grip portion 20 is formed in the same manner as the half member 30. Further, the grip portion 21 is configured in the same manner as the grip portion 20 formed by combining the half-shaped members 30 and 31.
The connecting rod 22 connecting the grip 20 and the grip 21 is formed in a long flat plate shape having fixing tool insertion holes at both ends. One end of the connecting rod 22 is sandwiched between the flat plate portion 35 of the half-shaped member 30 and the flat plate portion of the half-shaped member 31 opposed thereto, and is fixed to the entire gripping portion 20 by the fixing tool 28. Similarly, the other end of the connecting rod 22 is also fixed to the grip portion 21.

As shown in FIG. 5, the outer peripheral surface portion of the excavation rod 2 gripped by the grip portion 20 of the excavation rod connecting member 8 (sliding contact surface with the grip portion 20) corresponds to the protrusion 36 of the grip portion 20. Thus, a plurality of band-like protrusions 32 are formed.
The protrusions 32 are a plurality of belt-like protrusions that are formed over the entire outer peripheral surface of the excavation rod 2 and are parallel to the axial direction of the excavation rod 2. The plurality of protrusions (annular bodies) 36 intersect perpendicularly. The intersection angle may not be vertical (90 degrees), but is preferably 45 to 90 degrees. Thus, by making the protrusion 32 and the protrusion 36 intersect perpendicularly or at an angle close thereto, the contact area between the protrusion 32 and the protrusion 36 is reduced, the frictional force is reduced, and the rotation state of the excavating rod 2 is reduced. Etc. can be improved.
The protrusion 32 is formed on the outer peripheral surface of the excavation rod 2 by, for example, processing a flat steel made by a manufacturer obtained by building up a wear-resistant superalloy member in advance (for example, a product made by Nippon Yutec Co., Ltd.). It may be formed by fitting in a pre-drilled groove and welding, or it may be formed as a build-up using a welding rod or the like, or it is a wear-resistant material that is a linear rod-shaped body It may be formed by fitting a conductive cemented carbide member.
Here, as a material of the build-up forming the protrusion 32, the protrusion 32 has a wear resistance to such an extent that the protrusion 32 is not greatly worn due to sliding contact with the protrusion 36 on the inner peripheral surface of the grip portion 20. As long as it is not particularly limited, a material having at least a hardness equal to or higher than that of the protrusion 36 is preferable. Examples of the material of the wear resistant cemented carbide member include tungsten carbide alloy, high chromium wear resistant cast iron, and high manganese wear resistant cast iron.

Similar to the excavation rod 2, a plurality of strip-shaped protrusions are also formed on the outer peripheral surface portion of the excavation rod 3 gripped by the grip portion 21 of the excavation rod connecting member 8.
The protrusions 32 and the protrusions 36 are not limited to the forms shown in FIGS. 3 to 5, and can take other forms. For example, the form opposite to the form shown in FIGS. 3 to 5, that is, the protrusion 32 of the excavation rod 2 is formed into a plurality of band-shaped (annular) protrusions extending in the circumferential direction of the excavation rod 2, and the gripping portion The twenty protrusions 36 may be formed as a plurality of belt-like (straight-line) protrusions extending in parallel with the axis of the excavation rod 2. Also in this case, since the protrusion 32 and the protrusion 36 intersect substantially perpendicularly, the contact area between these protrusions is reduced, and the rotation state of the excavation rod 2 can be improved.

In the present invention, it is possible to provide only the protrusion 32 on the outer peripheral surface of the excavation rod 2 without providing the protrusion 36 on the inner peripheral surface of the grip portion 20. In this case, the protrusions 32 do not have to be formed in a band shape, and may be formed as, for example, a large number of truncated cone-shaped protrusions.
As shown in FIG. 6, the flanges 23 and 24 that support the gripping portion 20 of the excavation rod connecting member 8 are provided with at least a part of the sliding contact surface, as shown in FIG. 6, in order to prevent wear due to the sliding contact with the gripping portion 20. The wear-resistant member 40 is used.
In FIG. 6, the wear-resistant member 40 is an annular molded body centering on the axis of the excavation rod 2, and is fitted into a groove formed in the main body of the flange 23 which is formed in advance. A continuous flat surface is formed together with the main body, and is a flat slidable contact surface with respect to the upper surface of the grip portion 20.

Similarly, a wear-resistant molded body 41 is mounted on the flange 24 as an annular member that forms a part of the upper surface thereof.
As described above, both the flanges 23 and 24 have a flat sliding contact surface with respect to the grip portion 20, and a part of these sliding contact surfaces is formed by the wear-resistant members 40 and 41. Even when the multi-axis ground excavator 1 is operated for a long period of time, the sliding contact surfaces of the flanges 23 and 24 are held flat, and rattling of the gripping portion 20 and occurrence of shake of the axis of the excavation rod 2 occur. Is prevented.
The flanges 25 and 26 are the same as the flanges 23 and 24.

It is a front view which shows an example of the multi-axis type ground excavation apparatus of this invention. It is a front view which expands and shows the connection structure of the excavation rod and excavation rod connection member in the multi-axis type ground excavation apparatus shown in FIG. It is a cross-sectional view which shows the state cut | disconnected by the AA line in FIG. It is a front view which shows the half-shaped member which comprises the holding part of the excavation rod connection member shown in FIG. It is a front view which shows the structure of the excavation rod in the state which removed the excavation rod connection member from the connection structure shown in FIG. It is a longitudinal cross-sectional view which shows the state which cut | disconnected the structure of the excavation rod shown in FIG. 5 in the vertical plane which passes along the axis line of an excavation rod.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Multi-axis type ground excavator 2,3 Excavation rod 4,5 Head 6,7 Excavation blade 8 Excavation rod connection member 9,10 Co-rotation prevention blade 11,12,13,14 Agitation blade 15 Agitation claw 16,17,18 , 19 Flange 20, 21 Gripping part 22 Connecting rod 23, 24, 25, 26 Flange 27, 28 Fastening tool 30, 31 Half-shaped member 32, 36 Abrasion-resistant protrusion 33 Bending part 34, 35 Flat part 37 Fastener insertion hole 40, 41 Wear-resistant member

Claims (5)

Multi-axis ground excavation comprising a plurality of excavation rods arranged in parallel to each other and one or more excavation rod connecting members for connecting the plural excavation rods to keep the excavation rods parallel to each other A device,
The drill rod connecting member has a plurality of gripping portions for gripping the plurality of drill rods rotatably;
Each of the plurality of excavation rods has a wear-resistant projection on an outer peripheral surface that is in sliding contact with the grip portion of the excavation rod connecting member.   2. The multi-axis ground excavation device according to claim 1, wherein the grip portion of the excavation rod connecting member has a wear-resistant projection on a sliding contact surface with the excavation rod.   The wear-resistant projections of the excavation rod and the wear-resistant projections of the excavation rod connecting member are each composed of a plurality of strip-like projections extending in parallel to each other, and the excavation The direction in which the belt-like projections of the rod extend and the direction in which the belt-like projections of the excavation rod connecting member extend intersect at an angle of 45 to 90 degrees to reduce the contact area between the belt-like projections. The multi-axis type ground excavation apparatus according to claim 2.   The excavation rod has a pair of flanges for sandwiching and supporting the grip portion of the excavation rod connecting member from both sides in the axial direction of the excavation rod, and each of the pair of flanges includes the grip portion. The multi-axis type ground excavation device according to any one of claims 1 to 3, further comprising an abrasion-resistant member that forms a part of a sliding surface against the surface. A flat steel made by a manufacturer, in which the wear-resistant protrusion on the outer peripheral surface of the drilling rod that is in sliding contact with the gripping portion of the drilling rod connecting member is prefabricated with a wear-resistant superalloy member. The multi-axis type ground according to any one of claims 1 to 4, wherein the multi-axis ground is formed by being processed and fitted into a groove drilled in advance on the outer peripheral surface of the excavation rod. Drilling rig.

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