JP2012112160A - Drilling unit and excavation method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable rotation of a rotational drive source (earth auger) to be rapidly and surely stopped with a simple structure.SOLUTION: An equipment frame body 18b of a rotational drive source 18 is connected with a columnar casing 12 via first rotation stop means 20b and 12a making these two components engage with each other in the axis rotation direction, and the columnar casing 12 is supported with respect to an apparatus fixing frame body 11 via second rotation stop means 22 and 12b making these two components engage with each other in the axis rotation direction. Rotational drive force generated in the equipment frame body 18b of the rotational drive source 18 is transferred to the columnar casing 12 by the first rotation stop means 20b and 12a, and the columnar casing 12 is locked in the rotation direction by the second rotation stop means 22 and 12b, thereby locking the equipment frame body 18b of the rotational drive source 18 in the rotation direction.

Description

  The present invention relates to a drilling device configured to drill a hole while pulling a columnar casing into the formation.

  Conventionally, there are various excavation methods for drilling formations, but in recent years, the so-called double-pipe down-the-hole hammer method that allows columnar casings to be left standing in the formation during drilling Is being adopted. According to the double pipe type down-the-hole hammer construction method, there is an advantage that pile driving can be performed even in a narrow land on a steep slope or in a site where it is easy to collapse.

  In actually carrying out such a double pipe type down-the-hole hammer method, for example, as shown in FIG. 12, a screw rod 2 and a down-the-hole hammer 3 are attached to an earth auger (electric motor) 1 as a rotational drive source. The pilot bit 4 connected thereto is inserted into a columnar casing 5 made of a hollow member, and the tip end portion of the pilot bit 4 is chucked on a ring bit 6 rotatably attached to the lower end of the columnar casing 5. Make me king. The ground auger (electric motor) 1 is started in a state where the entire apparatus is erected and aligned with the pile core, and the pilot bit 4 and the ring bit 6 are rotated in the drilling direction by the rotational driving force. Try to make holes.

  Thus, when rotating the earth auger (electric motor) 1 as a rotation drive source, it is necessary to stop the rotation of the device frame 1a that constitutes the housing of the earth auger 1; In the apparatus, a plurality of arm portions 1b projecting substantially horizontally are provided on the device frame 1a of the earth auger 1, and the fixing wire 7 is passed through each of the arm portions 1b. The lower ends of the respective fixing wires 7 are connected to the anchors 8 that are placed in the fixed state to make them fixed.

  However, when the fixing wire 7 is arranged on the earth auger 1 in this way, it takes a considerable amount of work time for handling the fixing wire 7 and the like, and the driving operation of the anchor 8 connecting the fixing wire 7 is enormous. This is one of the causes of shortening the construction period and hindering safety.

  On the other hand, as described in Patent Document 1 below, on the outer peripheral surface of the columnar casing connected to the earth auger, an anti-rotation plate (connection reinforcing member) protruding outward is provided, and the anti-rotation plate is Proposals have been made in the past to prevent rotation of the columnar casing and the earth auger by engaging with a reaction force stopping means installed on the formation. According to such an apparatus according to the proposal, it is possible to stop the rotation of the earth auger without using the fixing wire as described above. However, when drilling, the outer peripheral surface of the columnar casing digs while contacting the hole wall surface, so-called crid method, in which the rotation stop plate provided to protrude outward from the columnar casing collides with the formation. Therefore, there is a problem that it becomes a serious obstacle and it is difficult to perform drilling. In addition, since the rotation is stopped by contact between the fixed members, the fixing members rub against each other when the columnar casing descends due to the progress of the drilling process. May become noise and cannot be used environmentally.

JP 2001-355181 A

  Accordingly, an object of the present invention is to provide an excavation apparatus and excavation method capable of quickly and reliably stopping rotation of a rotation drive source (earth auger) with a simple configuration.

  In order to solve the above problems, in the excavation apparatus according to the present invention, a columnar casing made of a long hollow member inserted toward the inside of a formation to be drilled, and the columnar casing in the hollow interior of the columnar casing. A pilot bit that is rotatably inserted around a substantially central axis, a ring bit that is rotatably attached to a lower end portion in the insertion direction of the columnar casing via a joint member, and a rotation of an output shaft that extends from the device frame A rotary drive source that applies a driving force to the pilot bit, and the columnar casing is erected at a drilling position via a device fixing frame constructed on the formation, and the pilot bit and the ring bit are In an excavation apparatus configured to be drilled in the formation by being rotationally driven by the rotational drive source, an equipment frame of the rotational drive source First rotation stopping means for connecting the columnar casing so as to be separable in the axial direction while being separable in the axial direction with respect to the central axis; and the columnar casing with respect to the device fixing frame, A configuration is employed that includes second rotation stopping means that is movable in the axial direction with respect to the shaft and supported so as to be engaged in the direction around the shaft.

  Further, in the excavation method according to the present invention, a columnar casing made of a long hollow member inserted toward the inside of the formation to be drilled, and a substantially central axis of the columnar casing in the hollow interior of the columnar casing. A pilot bit that is rotatably inserted, a ring bit that is rotatably attached to a lower end portion in the insertion direction of the columnar casing via a joint member, and a rotational driving force of an output shaft that extends from the device frame body. It is a construction method using an excavator provided with a rotation drive source to be applied to a bit, and the columnar casing is erected at a drilling position via an apparatus fixing frame constructed on the formation, and the pilot bit and In an excavation method in which the ring bit is rotated by the rotation drive source to drill holes in the formation, the device frame of the rotation drive source and the front The columnar casing is connected so as to be separable in the axial direction while being separable in the axial direction with respect to the central axis, and the columnar casing can be moved in the axial direction with respect to the central axis relative to the device fixing frame. However, the structure which supports so that it may engage in the periphery of an axis | shaft is employ | adopted.

  According to the excavating apparatus and excavation method having such a configuration, the rotational driving force generated in the device frame of the rotational driving source is transmitted to the columnar casing via the first rotation stopping means. Since the second rotation stop means is locked in the rotation direction, the device frame of the rotation drive source is locked in the rotation direction. As a result, the output shaft of the rotational drive source, the pilot bit and the ring bit are smoothly rotated in the driving direction, and the rotational stop of the rotational drive source with respect to the device frame is performed by a simple anti-rotation means via the columnar casing. Therefore, a large-scale operation such as deployment of a fixed wire to the rotational drive source and driving of an anchor as in the prior art becomes unnecessary, and the construction period is shortened and the safety is improved.

  The first rotation stop means according to the present invention includes a hollow cylindrical member attached to an equipment frame of the rotation drive source, and an inner peripheral surface of the hollow cylindrical member and an outer peripheral surface of the columnar casing. Further, it is desirable that a rotation engagement plate that is separable in the axial direction with respect to the central axis and is engaged in the direction around the axis is provided.

  With such a configuration, a reliable anti-rotation action can be obtained while the first anti-rotation means has a simple configuration.

  Further, the second rotation stop means according to the present invention has a rotation roller rotatably attached to the device fixing frame, and the rotation roller is disposed on the outer peripheral surface of the columnar casing in the axial direction of the central axis. It is desirable that a rotation engagement groove that is engaged in a direction around the axis while being movable is provided.

  With such a configuration, a reliable anti-rotation action can be obtained while making the second anti-rotation means simple. In particular, since the rotation engaging groove constituting the second rotation stopping means is recessed inward from the outer peripheral surface of the columnar casing, the hole is drilled like a conventional rotation stopping plate protruding outward from the outer peripheral surface of the columnar casing. Drilling work is performed smoothly without obstructing the process. Further, when the columnar casing is lowered due to the progress of the drilling stroke, the lowering of the columnar casing is smoothly guided by the rolling of the rotating roller constituting the second rotation preventing means, and the conventional rubbing is rubbed. Noise such as sound hardly occurs, and extremely good drilling work is possible in the environment.

  As described above, the excavation apparatus and excavation method according to the present invention includes the first rotation stop means so that the device frame body of the rotational drive source and the columnar casing can be engaged in the axial direction while being separable in the axial direction. And a device of a rotational drive source by a configuration in which the columnar casing is axially movable with respect to the apparatus fixing frame body and supported via the second anti-rotation means so as to be engaged in the direction around the axis. The rotational driving force generated in the frame body is transmitted to the columnar casing through the first rotation stopping means, and the columnar casing is locked in the rotation direction by the second rotation stopping means to rotate the device frame of the rotation driving source in the rotation direction. , The output shaft of the rotary drive source, the pilot bit and the ring bit are smoothly rotated in the drive direction, and the rotation stopper for the device frame of the rotary drive source is prevented from being rotated by the columnar case. It is constructed by simple rotation stop means through a sing, and it eliminates the need for large-scale work such as deployment of fixed wires and driving anchors as in the past, and shortens the construction period and increases safety. Therefore, with a simple configuration, the rotation drive source (earth auger) can be quickly and reliably stopped, and the reliability of the excavation apparatus and excavation method can be greatly improved at low cost.

In the excavation equipment concerning one embodiment of the present invention, it is a fragmentary longitudinal section explanatory view showing the state of the preparation stage which inserts a pilot bit into the inside of a columnar casing. FIG. 2 is a partial cross-sectional explanatory view showing a state after a pilot bit is inserted into a columnar casing in the excavator shown in FIG. 1. FIG. 3 is a longitudinal sectional explanatory view showing a lower end portion (head portion) of the excavator shown in FIGS. 1 and 2. FIG. 3 is a longitudinal cross-sectional explanatory view showing a first rotation stop means arranged at an upper end portion of the excavator shown in FIGS. 1 and 2. It is a cross-sectional explanatory drawing along the VV line in FIG. FIG. 4 is a cross-sectional explanatory view taken along line VI-VI in FIG. 3. It is side surface explanatory drawing of the pilot bit used for the excavator shown in FIGS. 1-3. It is front explanatory drawing of the pilot bit shown by FIG. It is side surface explanatory drawing of the ring shoe used for the excavation apparatus shown by FIGS. It is side surface explanatory drawing of the ring bit used for the excavation apparatus shown by FIGS. It is front explanatory drawing of the ring bit shown by FIG. It is a partial cross section explanatory view showing the state after inserting a pilot bit into the inside of a columnar casing in the excavator generally used.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following explanation, it is assumed that the excavation propulsion direction is a downward direction assuming drilling.

  First, when using the excavator according to the embodiment of the present invention shown in FIG. 1 and FIG. 2, the device fixing frame 11 is first constructed at a predetermined pile core position of the formation T where drilling is performed. Then, the columnar casing 12 made of a long hollow circular tube member is inserted into the device fixing frame 11 so that the columnar casing 12 is erected in a substantially vertical direction at a predetermined pile core position. It is designed to be held in a state.

  The columnar casing 12 is inserted toward the inside of the formation T to be drilled, and at the lower end of the columnar casing 12, as shown in FIG. A ring bit 14 is rotatably attached via the shoe 13. A pilot bit 15 that is driven to rotate about the substantially central axis of the columnar casing 12 is inserted into the hollow interior of the columnar casing 12. The pilot bit 15 is chucked in a state where rotation can be transmitted to the above-described ring bit 14 as described later.

  A down-the-hole hammer 16 and an auger screw 17 are connected to an upper end portion of the pilot bit 15, and the pilot bit 15 is connected to an output shaft 18 a of an earth auger 18 as a rotational drive source via both members 16, 17. It is connected. The earth auger (rotation drive source) 18 is provided with an electric motor inside the device frame 18b, and the pilot bit 15 and the ring are driven by the rotation drive force of the output shaft 18a extending downward from the device frame 18b. The bit 14 is rotated in the excavation direction.

  In addition, as described above, the columnar casing 12 is formed from a long hollow circular pipe member, but as described later, the columnar casing 12 is left as it is standing on the formation T as a support pile immediately after excavation, It is pulled out after the main pile member such as steel is inserted inside.

  Further, the pilot bit 15 inserted into the hollow interior of the columnar casing 12 has a drive shaft portion 15a having a relatively small diameter, and has a relatively large diameter at the lower end portion of the drive shaft portion 15a. A head portion 15b is provided. Center-side drill pieces 15c made up of a number of protruding members are provided on the front end surface (lower end surface) of the head portion 15b so as to be transmitted through the drive shaft portion 15a described above. The head portion 15b is rotated by the rotational driving force, and the formation is excavated by the cutting action of the center side drill piece 15c at that time, so that a drilling hole is formed downward in the formation T.

  Further, the head portion 15b is formed with an air passage 15d extending from the auger screw 17 and the down-the-hole hammer 16 to the drive shaft portion 15a in the substantially central axis direction. The air passage 15d extends along substantially the center of the drive shaft portion 15a and the head portion 15b, and branches into a plurality (four bodies) in the vicinity of the tip portion (lower end portion) of the head portion 15b. These branch paths are formed so as to open to the front end surface (lower end surface) of the head portion 15b.

  Further, a discharge groove 15e is provided so as to extend radially outward from each opening of the air passage 15d described above. Each of the discharge grooves 15e extends radially to the outer peripheral portion of the head portion 15b, and then extends in the axial direction from the outer peripheral portion of the head portion 15b to the outer peripheral surface of the head portion 15b. It is provided so that it may open to the upper end surface on the opposite side. The opening on the upper end side of each of the discharge grooves 15e communicates with the internal space of the columnar casing 12, and waste soil or the like generated during drilling is discharged by the air supplied from the air passage 15d. It is configured to be discharged through.

  On the other hand, a casing shoe 13 as a joint member is fixed to the lower end portion in the axial direction of the columnar casing 12 by welding. The casing shoe (joint member) 13 is formed of a hollow tubular member, and a ring is formed at the lower end portion of the casing shoe 13 so as to be rotatable about the substantially central axis of the columnar casing 12. The bit 14 is configured to be attached. Further, the pilot bit 15 described above is rotatably inserted into the casing shoe 13.

  The above-described ring bit 14 is also formed of a hollow tubular member, and a large number of outer peripheral drill pieces 14a are provided on the outer peripheral portion of the lower end surface of the ring bit 14 so as to form protrusions. The ring bit 14 is rotated by a predetermined rotational driving force transmitted from the bit 15 through the mount structure described below, and the outer periphery of the columnar casing 12 is cut by the cutting action of the outer peripheral side drill piece 14a at that time. Excavation is performed at a position corresponding to the section.

  As described above, the pilot bit 15 is rotatably inserted inside the ring bit 14. The ring bit 14 and the pilot bit 15 are attached and detached (chat) by a so-called bayonet mount. King) is made possible. That is, as shown in FIGS. 7 to 11 in particular, lock portions 15f and 14b in which the concavo-convex relationship in the radial direction is reversed are provided on the inner peripheral wall surfaces of the pilot bit 15 and the ring bit 14. Yes. The lock portions 15f and 14b are configured to be fitted at a specific angular position and to be in a non-fitted state at other angular positions, and the lock portions 15f and 14b are connected to each other. After the ring bit 14 and the pilot bit 15 are fitted in the axial direction at an angular position where they are not fitted, the ring bit 14 and the pilot bit 15 can be rotated so as to be relatively shifted from each other by an appropriate center angle from the fitting position at that time. Thus, both the lock portions 15f and 14b are in the axially fitted state, and are fitted in one of the circumferential directions and not in the other direction.

  Then, when the ground auger 18 is started from the fitting state of the pilot bit 15 and the ring bit 14, and the pilot bit 15 is rotationally driven in a specific direction by the rotational driving force of the output shaft 18a, the pilot bit 15 The ring bit 14 fitted in the circumferential direction with respect to 15 is rotated, and the formation T is excavated by the center side drill piece 15c and the outer side drill piece 14a provided in the pilot bit 15 and the ring bit 14, The downward propulsion force is applied from the down-the-hole hammer 16 described above. In particular, the outer peripheral side drill piece 14a of the ring bit 14 forms an outer peripheral wall surface of the drilling hole, and the columnar casing 12 described above is inserted along the outer peripheral wall surface of the drilling hole.

  Further, the main body base portion 13a constituting the upper portion of the above-described casing shoe (joint member) 13 is attached to the outer peripheral portion of the head portion 15b of the pilot bit 15 so as to be axially movable and rotatable. In addition, the ring bit 14 described above is rotatably accommodated on the inner peripheral side of the support portion 13b extending downward from the main body base portion 13a. Between the main body base portion 13a of the casing shoe 13 and the upper end surface of the ring bit 14, a moving space for the casing shoe 13 to move in the axial direction is formed.

  Thus, the movement space of the casing shoe (joint member) 13 is between the surfaces where the main body base portion 13a of the casing shoe 13 and the upper end surface of the ring bit 14 are opposed to each other in the axial direction (hereinafter, between the axially facing surfaces). However, when the moving space is viewed in the radial direction, the pilot bit 15 on the radially inner side and the casing shoe 13 on the radially outer side face each other in the radial direction. It is formed between the planes (hereinafter referred to as “radially facing surfaces”).

  A buffer member 19 having elasticity in at least the axial direction is disposed inside the moving space formed between the axially facing surfaces and between the radially facing surfaces. As the buffer member 19 in the present embodiment, an annular coil spring that extends spirally in the circumferential direction is employed. The buffer member 19 made of this annular coil spring is basically arranged so as to exert a buffer function by being interposed in the axial direction at a portion between the main body base portion 13a of the casing shoe 13 and the upper end surface of the ring bit 14. However, the buffer member 19 has a function as a rotational force transmitting means between the pilot bit 15 and the ring bit 14 which are rotating members.

  On the other hand, as described above, the equipment frame 18b of the earth auger 18 serving as the rotational drive source is formed on the columnar casing 12 via the rotation stopping cap 20 serving as the first rotation stopping means, as particularly shown in FIG. It is connected to the upper end part. The anti-rotation cap 20 has a cap body 20a made of a hollow cylindrical member, and the closed edge portion on the upper end side of the cap body 20a is the outer periphery on the lower end side of the equipment frame 18b of the earth auger 18. It is fixed to the surface by welding or the like. And the cap main body 20a which comprises this rotation stop cap 20 is externally fitted so that the outer side of the upper end part of the said columnar casing 12 may be covered from the opening part provided in the lower end side of the said cap main body 20a. It is made the structure which is mounted by doing.

  At this time, as shown in FIG. 5, the cap-side rotation engagement plate 20b protruding inward toward the central axis is formed on the inner peripheral surface of the cap body 20a constituting the rotation stopper cap 20 described above. Four bodies are provided at substantially equal intervals along the circumferential direction. Correspondingly, on the outer peripheral surface of the columnar casing 12, four casing-side rotation engagement plates 12a projecting outward from the central axis are provided at substantially equal intervals along the circumferential direction. As described above, when the cap main body 20a of the rotation stopper cap 20 is mounted so as to cover the columnar casing 12 from the outer side, the cap side rotation engagement plate 20b and the casing side rotation engagement plate 12a are connected. The positions are arranged so as to face each other in the circumferential direction.

  Then, when the earth auger 18 as a rotational drive source is slightly rotated, the members 20a and 12a are brought into contact with each other in the circumferential direction, and then the earth auger 18 is rotationally driven. The rotational driving force from the output shaft 18a is transmitted to the columnar casing 12 side via both members 20a and 12a. In this way, by configuring the first rotation stop means by the cap-side rotation engagement plate 20b and the casing-side rotation engagement plate 12a made of a plate-like member, a reliable rotation stop action can be obtained with a simple configuration.

  Further, as described above, the columnar casing 12 is erected in a substantially vertical direction at a predetermined pile core position by inserting the lower end portion of the columnar casing 12 into the inside of the device fixing frame 11 constructed in the formation. It is supposed to be kept in the state. At this time, as shown in FIG. 3, a pair of rotating rollers 22, 22 as second rotation stopping means are attached to the apparatus fixing frame 11. Each of these rotating rollers 22 is rotatably attached to a bearing plate 22a disposed on the upper surface of the device fixing frame 11 so as to be detachable and positionally movable, and corresponds to a pile core on the device fixing frame 11. Then, the columnar casing 12 is fixed by appropriate fixing means so as to sandwich the columnar casing 12 from the outer side in the diameter direction.

  On the other hand, as shown in FIG. 6, a pair of rotation engagement grooves 12 b and 12 b for receiving the above-described pair of rotation rollers (second rotation stopping means) 22 are formed on the outer peripheral surface of the columnar casing 12. It is recessed. Each of the rotation engaging grooves 12b also constitutes a second rotation stopping means, and has a groove width and a groove depth that can accommodate the outer end portion in the radial direction of the rotating roller 22 described above. The columnar casing 12 excluding the pilot bit 15 and the ring bit 14 described above extends substantially over the entire length.

  As shown in FIG. 3, the rotation of the columnar casing 12 is locked by the rotation roller 22 by accommodating a part of the rotation roller 22 in the rotation engagement groove 12 b of the columnar casing 12. On the other hand, when the rotary roller 22 rolls up and down the bottom surface of the rotation engagement groove 12b, the entire columnar casing 12 is supported so that it can arbitrarily reciprocate along the central axis direction (vertical direction). The structure is made.

  Thus, by configuring the second rotation stop means by the rotation roller 22 and the rotation engagement groove 12b, a reliable rotation stop action can be obtained while having a simple configuration. Further, when the columnar casing 12 descends due to the progress of the drilling stroke, the descending of the columnar casing 12 is smoothly guided by the rolling of the rotating roller 22 constituting the second rotation stopping means, Such noises such as rubbing noise hardly occur, and extremely excellent drilling work is possible in the environment.

  At this time, the pair of rotation engagement grooves 12b and 12b provided in the columnar casing 12 is disposed at a position corresponding to the discharge groove 15e of the pilot bit 15 described above, and the rotation engagement groove 12b The outer shape is formed to be slightly smaller than the discharge groove 15e. Thus, when the pilot bit 15 moves inside the columnar casing 12, the discharge groove 15e on the pilot bit 15 side does not interfere with the rotation engagement groove 12b on the columnar casing 12 side.

  In forming a hole by excavation using the excavator having such a configuration, the following crid method is used. First, the apparatus is carried into the site, and the apparatus fixing frame 11 is constructed in the formation T for drilling, while the casing shoe (joint member) 2 is welded to the lower end portion of the columnar casing 12. A ring bit 14 is rotatably attached to the casing shoe 13 at that time. The columnar casing 12 to which the ring bit 14 is attached is inserted into the device fixing frame body 11 and is held in a state in which it stands in a substantially vertical direction. At this time, a pair of rotation rollers (second anti-rotation means) 22 and 12 attached to the apparatus fixing frame 11 side are inserted into a pair of rotation engagement grooves 12b and 12b provided in the columnar casing 12, respectively. .

  Next, as shown in FIG. 1, the pilot bit 15 connected to the output shaft 18 a of the earth auger 18 via the down-the-hole hammer 16 and the auger screw 17 is inserted into the columnar casing 12 from the upper end. It is chucked by the ring bit 14 arranged at the lower end portion. Then, the earth auger 18 is rotated and activated to apply a rotational driving force to the pilot bit 15 and the ring bit 14, whereby the center side drill piece 15c and the outer peripheral side drill piece 14a of the pilot bit 15 and the ring bit 14 Drilling is performed and drilling work is performed.

  At this time, the rotational driving force generated in the device frame 18b of the earth auger 18 is transmitted to the columnar casing 12 via the rotation stopper cap (first rotation stopping means) 20, and the columnar casing 12 includes a rotation roller. Since (second anti-rotation means) 22 is locked in the rotation direction, the device frame 18b of the earth auger 18 is locked in the rotation direction. As a result, the output shaft 18a of the earth auger 18, the pilot bit 15 and the ring bit 14 are smoothly rotated in the driving direction. As described above, since the rotation of the earth auger 18 with respect to the equipment frame 18b is performed by the rotation stoppers 10 and 12 having a simple configuration via the columnar casing 12, the fixing wire for the earth auger 18 as in the prior art is used. Large-scale work such as deployment and anchor driving becomes unnecessary, and the construction period is shortened and the safety is improved.

  In particular, in the present embodiment, the rotation engagement groove 12b constituting the second rotation stopping means is not inwardly recessed from the outer peripheral surface of the columnar casing 12 and protrudes outward. The hole drilling operation is smoothly performed without obstructing the hole drilling unlike the conventional rotation stopper plate protruding outward. Further, as the drilling progresses, the columnar casing 11 descends due to the rolling of the rotating roller 22 constituting the second anti-rotation means, so that noise such as a conventional rubbing noise hardly occurs and the environment is reduced. In addition, extremely good drilling work is possible.

  Further, at the time of drilling by rotating the pilot bit 15 and the ring bit 14 as described above, downward propulsive force is applied from the columnar casing 12 to the ring bit 14 via the casing shoe (joint member) 13. This downward driving force is applied at a predetermined cycle as a strong axial pressing force by a hammer device or the like, so that the drilling operation is performed quickly.

  During this drilling operation, the columnar casing 12 is stood in the formation T so as to be pulled into the ring bit 14. When the drilling reaches a predetermined depth, the pilot bit 15 is connected to the ring bit 14. Separate from chucking and pull up. Then, instead of the raised pilot bit 15, a pile made of steel or the like is inserted into the columnar casing 12 and driven into the formation T, and finally the columnar casing 12 is pulled out from the formation T.

  Although the embodiments of the invention made by the present inventor have been specifically described above, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the invention. Not too long.

  For example, as the first and second rotation stop means according to the present invention, various mechanisms and members other than the members as in the above-described embodiment can be employed.

T stratum 11 device fixed frame 12 columnar casing 12a casing side rotation engagement plate 12b rotation engagement groove (second rotation stop means)
13 casing shoe 13a body base portion 13b support portion 14 ring bit 14a outer periphery side drill piece 14b lock portion 15 pilot bit 15a drive shaft portion 15b head portion 15c center side drill piece 15d air passage 15e discharge groove 15f lock portion 16 down the hole hammer 17 auger screw 17 18 Earth auger 18a Output shaft 18b Equipment frame 19 Buffer member 20 Anti-rotation cap (first anti-rotation means)
20a Cap body 20b Cap side rotation engagement plate 22 Rotating roller (second rotation stopping means)
22a Bearing plate

In order to solve the above problems, in the excavation apparatus according to the present invention, a columnar casing made of a long hollow member inserted toward the inside of a formation to be drilled, and the columnar casing in the hollow interior of the columnar casing. A pilot bit that is rotatably inserted around a substantially central axis, a ring bit that is rotatably attached to a lower end portion in the insertion direction of the columnar casing via a joint member, and a rotation of an output shaft that extends from the device frame A rotary drive source for applying a driving force to the pilot bit, and standing the columnar casing at a drilling position via a device fixing frame constructed on the formation, and a head portion of the pilot bit and the pilot bit There rows drilling to the stratum ring bit is rotated by the rotary drive source, Jikukata on the outer peripheral surface of the head portion of the pilot bit Axially configured rigs as waste soil occurring during boring is discharged, the device frame of the rotary drive source and said columnar casing, about the central axis through the discharge groove provided so as to extend in A first anti-rotation means coupled so as to be separable while being separable, and the columnar casing being movable in the axial direction relative to the central axis with respect to the device fixing frame. And a second anti-rotation means for supporting the second anti-rotation means so that the second anti-rotation means is engaged with the apparatus fixing frame body. The outer circumferential surface of the columnar casing has an inwardly-engaged rotation engagement groove that receives the rotation roller and engages the rotation roller in the axial direction of the central axis while engaging the rotation roller in the axial direction. The rotation engagement groove extends in a portion excluding the portion facing the head portion of the pilot bit and corresponds to the discharge groove of the pilot bit in the direction around the axis. And is formed in an outer shape smaller than the discharge groove so that the pilot bit does not interfere with the rotation engagement groove when the pilot bit moves in the axial direction inside the columnar casing. It has been adopted.

Further, in the excavation method according to the present invention, a columnar casing made of a long hollow member inserted toward the inside of the formation to be drilled, and a substantially central axis of the columnar casing in the hollow interior of the columnar casing. A pilot bit that is rotatably inserted, a ring bit that is rotatably attached to a lower end portion in the insertion direction of the columnar casing via a joint member, and a rotational driving force of an output shaft that extends from the device frame body. It is a construction method using an excavator provided with a rotation drive source to be applied to a bit, and the columnar casing is erected at a drilling position via an apparatus fixing frame constructed on the formation, and the pilot bit and the ring bit have rows drilling to the formation are rotationally driven by the rotary drive source, extends in the axial direction on the outer peripheral surface of the pilot bit In drilling method for discharging waste soil produced during drilling through the discharge groove provided to, by using the first rotation preventing means of the above-mentioned drilling apparatus, equipment frame of the rotary drive source and the said columnar casing, The columnar casing is connected to the device fixing frame by using the second rotation stopping means of the excavating device , which is connected so as to be engaged in the axial direction while being separable in the axial direction with respect to the central axis. By using the rotation engagement groove and the pilot bit of the second rotation stop means of the excavator described above, the columnar shape can be supported while being movable in the axial direction with respect to the central axis. A configuration is adopted in which the pilot bit does not interfere with the rotation engagement groove when the pilot bit moves in the axial direction inside the casing .

Further, by the present invention having the structure described above lever, while the a simple configuration a second rotation stop means, a reliable detent action is obtained. In particular, since the rotation engaging groove constituting the second rotation stopping means is provided inwardly from the outer peripheral surface of the columnar casing, it is like a conventional rotation stopping plate protruding outward from the outer peripheral surface of the columnar casing. Therefore, the drilling operation is performed smoothly without obstructing the drilling. Further, when the columnar casing is lowered due to the progress of the drilling stroke, the lowering of the columnar casing is smoothly guided by the rolling of the rotating roller constituting the second rotation preventing means, and the conventional rubbing is rubbed. Noise such as sound hardly occurs, and extremely good drilling work is possible in the environment.

As described above, the excavation apparatus and excavation method according to the present invention includes the first rotation stop means so that the device frame body of the rotational drive source and the columnar casing can be engaged in the axial direction while being separable in the axial direction. with connecting through, apparatus and rotating roller provided on the stationary frame, while enabling moving the rotary engaging groove which is provided so as to be recessed inwardly on the outer peripheral surface of the columnar casing against the rotation roller in the axial direction By means of a configuration that supports through the second rotation stop means so as to engage in the direction around the axis, the rotational driving force generated in the device frame of the rotation drive source is transmitted to the columnar casing through the first rotation stop means, In addition, the columnar casing is locked in the rotation direction by the second rotation stop means, and the device frame of the rotation drive source is locked in the rotation direction, so that the output shaft of the rotation drive source, the pilot bit and the ring bit are Is rotated smoothly in the driving direction, and the rotation of the rotation drive source with respect to the device frame is performed by a simple rotation stop means via the columnar casing. Because it is configured to shorten the construction period and improve safety without requiring large-scale work such as driving in, the rotation drive source (earth auger) can be stopped quickly and reliably with a simple configuration. In addition, the reliability of the excavator and the excavation method can be inexpensively and greatly improved.

In order to solve the above problems, in the excavation apparatus according to the present invention, a columnar casing made of a long hollow member inserted toward the inside of a formation to be drilled, and the columnar casing in the hollow interior of the columnar casing. A pilot bit that is rotatably inserted around a substantially central axis, a ring bit that is rotatably attached to a lower end portion in the insertion direction of the columnar casing via a joint member, and a rotation of an output shaft that extends from the device frame A rotary drive source for applying a driving force to the pilot bit, and standing the columnar casing at a drilling position via a device fixing frame constructed on the formation, and a head portion of the pilot bit and the pilot bit There rows drilling to the stratum ring bit is rotated by the rotary drive source, Jikukata on the outer peripheral surface of the head portion of the pilot bit Axially configured rigs as waste soil occurring during boring is discharged, the device frame of the rotary drive source and said columnar casing, about the central axis through the discharge groove provided so as to extend in A first anti-rotation means coupled so as to be separable while being separable, and the columnar casing being movable in the axial direction relative to the central axis with respect to the device fixing frame. And a second anti-rotation means for supporting the first anti-rotation means so that the first anti-rotation means is attached to the device frame of the rotational drive source from the outside of the columnar casing. A hollow cylindrical member mounted so as to be covered, and is separable in an axial direction with respect to the central axis on an inner peripheral surface of the hollow cylindrical member and an outer peripheral surface of the columnar casing; While the rotation engagement plates to be combined are respectively provided, the second rotation stopping means has a rotation roller rotatably attached to the device fixing frame body, and on the outer peripheral surface of the columnar casing. A rotation engaging groove for receiving the rotating roller and engaging the rotating roller in the axial direction while allowing the rotating roller to move in the axial direction of the central axis is recessed so as to be recessed inward from the outer peripheral surface of the columnar casing. The rotation engagement groove extends to a portion excluding the portion facing the head portion of the pilot bit, and is disposed at a position corresponding to the discharge groove of the pilot bit in the direction around the axis, and By forming the outer shape smaller than the discharge groove, the rotation of the pilot bit moves in the axial direction inside the columnar casing. A configuration that does not interfere with the engagement groove is employed.

Further, in the excavation method according to the present invention, a columnar casing made of a long hollow member inserted toward the inside of the formation to be drilled, and a substantially central axis of the columnar casing in the hollow interior of the columnar casing. A pilot bit that is rotatably inserted, a ring bit that is rotatably attached to a lower end portion in the insertion direction of the columnar casing via a joint member, and a rotational driving force of an output shaft that extends from the device frame body. It is a construction method using an excavator provided with a rotation drive source to be applied to a bit, and the columnar casing is erected at a drilling position via an apparatus fixing frame constructed on the formation, and the pilot bit and the ring bit have rows drilling to the formation are rotationally driven by the rotary drive source, extends in the axial direction on the outer peripheral surface of the pilot bit In drilling method for discharging waste soil produced during drilling through the discharge groove provided to, by using the first rotation preventing means of the above-mentioned drilling apparatus, equipment frame of the rotary drive source and the said columnar casing, The columnar casing is connected to the device fixing frame by using the second rotation stopping means of the excavating device , which is connected so as to be engaged in the axial direction while being separable in the axial direction with respect to the central axis. By using the rotation engagement groove and the pilot bit of the second rotation stop means of the excavator described above, the columnar shape can be supported while being movable in the axial direction with respect to the central axis. A configuration is adopted in which the pilot bit does not interfere with the rotation engagement groove when the pilot bit moves in the axial direction inside the casing .

Also, lever by the present invention having the structure described above, while the first rotation stopper means and the second rotation preventing means is a simple construction, reliable detent action is obtained. In particular, since the rotation engaging groove constituting the second rotation stopping means is provided inwardly from the outer peripheral surface of the columnar casing, it is like a conventional rotation stopping plate protruding outward from the outer peripheral surface of the columnar casing. Therefore, the drilling operation is performed smoothly without obstructing the drilling. Further, when the columnar casing is lowered due to the progress of the drilling stroke, the lowering of the columnar casing is smoothly guided by the rolling of the rotating roller constituting the second rotation preventing means, and the conventional rubbing is rubbed. Noise such as sound hardly occurs, and extremely good drilling work is possible in the environment.

Or drilling equipment and drilling method according to the present invention, as mentioned, first consists rotational engagement plate to engage around the axis while allowing separation of the device frame body of the rotary drive source and a columnar casing in the axial direction with linked via the 1 rotation stopping means, a rotary roller provided in the apparatus stationary frame element, the rotation engagement groove and the axial direction which is provided so as to be recessed inwardly on the outer peripheral surface of the columnar casing against the rotation roller The rotational driving force generated in the device frame of the rotational drive source is columnar via the first anti-rotation means by the structure that supports it via the second anti-rotation means so as to be engaged in the direction around the axis while being movable. By transmitting to the casing and locking the columnar casing in the rotation direction by the second rotation stop means and locking the device frame of the rotation drive source in the rotation direction, the output shaft of the rotation drive source and the pilot And the rotation of the rotating bit in the driving direction, and the rotation of the rotation source with respect to the device frame is performed by a simple rotation stopping means via a columnar casing. Because it is configured to shorten the construction period and increase safety without requiring large-scale work such as deployment and anchor driving, the rotation drive source (earth auger) can be stopped quickly and reliably with a simple configuration. Therefore, the reliability of the excavation apparatus and excavation method can be greatly improved at low cost.

Claims (4)

A columnar casing made of a long hollow member inserted toward the inside of the formation to be drilled, and a pilot bit inserted into the hollow interior of the columnar casing so as to be rotatable about a substantially central axis of the columnar casing; A ring bit rotatably attached to a lower end portion in the insertion direction of the columnar casing via a joint member; and a rotation drive source that applies a rotation driving force of an output shaft extending from the device frame to the pilot bit. Prepared,
The columnar casing is erected at a drilling position through a device fixed frame constructed on the formation, and the pilot bit and the ring bit are driven to rotate by the rotary drive source to make a hole in the formation. In a drilling rig configured to perform
A first rotation stop means for connecting the device frame of the rotation drive source and the columnar casing so as to be engaged in a direction around the axis while being separable in an axial direction with respect to the central axis;
Second rotation stopping means for supporting the columnar casing so as to be movable in the axial direction with respect to the central axis while being engaged with the device fixing frame body in the axial direction;
A drilling rig characterized by comprising: The first rotation stopping means has a hollow cylindrical member attached to the device frame of the rotation drive source,
A rotation engagement plate that is separable in an axial direction with respect to the central axis and engages in a direction around the axis is provided on each of an inner peripheral surface of the hollow cylindrical member and an outer peripheral surface of the columnar casing. Item 2. The excavator according to item 1. The second anti-rotation means has a rotating roller rotatably attached to the device fixing frame,
2. The excavation according to claim 1, wherein a rotation engagement groove is provided on an outer peripheral surface of the columnar casing so as to engage the rotation roller in the axial direction while being movable in the axial direction of the central axis. apparatus. A columnar casing made of a long hollow member inserted toward the inside of the formation to be drilled, and a pilot bit inserted into the hollow interior of the columnar casing so as to be rotatable about a substantially central axis of the columnar casing; A ring bit that is rotatably attached to a lower end portion in the insertion direction of the columnar casing via a joint member, and a rotation drive source that applies a rotation driving force of an output shaft extending from the device frame to the pilot bit. A construction method using a drilling rig,
The columnar casing is erected at a drilling position through a device fixed frame constructed on the formation, and the pilot bit and the ring bit are driven to rotate by the rotary drive source to make a hole in the formation. In the excavation method
The device frame of the rotational drive source and the columnar casing are coupled so as to be engaged in the axial direction while being separable in the axial direction with respect to the central axis,
An excavation method characterized by supporting the columnar casing so as to be movable in an axial direction with respect to the central axis while being engaged with the device fixing frame body in a direction around the axis.

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