JP2018193707A - Drilling machine and drilling method for driving underground heat exchange pipe - Google Patents

Abstract

To provide a drilling machine capable of preventing a vertical hole for driving an underground heat exchange pipe from collapsing during drilling.SOLUTION: A drilling method for a driving underground heat exchange pipe comprises: a first process to drill a vertical hole 3 into the ground by an auger screw 4 and a casing 9 as rotating and pressing an expansion rod 6a and the casing 9; a second process to continue drilling by the auger screw 4 and the casings 9, 10 which is configured by adding a next casing 10 to the casing 9 while the expansion rod 6a is in an expanded status; a third process to further continue drilling the vertical hole 3 by another expansion rod 6a and next casings 9, 10 added to the existing ones; a fourth process to leave only the casings 9, 10 in the vertical hole 3 after repeating the second and third processes to deeply drill the hole to an objective depth; and a fifth process to withdraw the casings 9, 10 out of the vertical hole 3 after inserting a vertically long underground heat exchange pipe within the casings 9, 10.SELECTED DRAWING: Figure 4

Description

  The present invention relates to an excavation apparatus and excavation method for excavating a vertical hole for embedding an underground heat exchange pipe in the ground.

  In order to use underground heat, underground heat exchange pipes are buried in the ground. The underground heat exchange pipe is buried by excavating a deep vertical hole of about 10 to 30 m with respect to the ground, pushing the underground heat exchange pipe into the excavated vertical hole, and then filling the vertical hole with soil. In such deep vertical hole excavation, a large boring machine is used. However, when a large boring machine is used, it is difficult to move the boring machine, and there is a problem that it is difficult to work in a narrow work site.

  Patent Document 1 describes a method of burying an underground heat exchange pipe using a digging column car used to build a power pole. The digging pillar car has the advantage of smooth movement at the work site because it is smaller and more mobile than a boring machine. This digging pillar car is equipped with an auger screw having a length of about 3 m and cannot dig deep vertical holes continuously. For this reason, the embedding method described in Patent Document 1 excavates a vertical hole by adding an extension rod.

  Such an embedding method described in Patent Document 1 includes a step of excavating a vertical hole having a target depth by repeating an operation of adding an extension rod to an auger screw of a digging pillar car, and a cylindrical casing after excavating the vertical hole. A step of forming a temporary inner wall by pushing into the vertical hole while adding a plurality of the above, and a step of removing the casing from the vertical hole after feeding the underground heat exchange pipe into the casing serving as the temporary inner wall. .

Japanese Patent No. 6001616

In the conventional burying method described in Patent Document 1, after excavating the vertical hole while adding the extension rod, the casing is pushed into the vertical hole while adding the casing. The excavation of the vertical hole is performed first. After that, the casing is pushed into the vertical hole.
However, in this method, when the vertical hole collapses and is buried with earth and sand during excavation of the vertical hole, it is not possible to push the casing or feed the underground heat exchange pipe thereafter. For this reason, there exists a problem which cannot be applied to soft grounds, such as spring soil soil and sandy soil, for example. In addition, since the extension rod is added when excavating the vertical hole and the casing is added when the casing is pushed in, the extension rod is added and the casing is added at different stages. For this reason, it has the problem that workability | operativity of excavation is bad.

  The present invention has been made in consideration of the problems of the conventional method as described above, and it is possible to prevent the collapse of a vertical hole during excavation and to bury an underground heat exchange pipe capable of improving workability. An object of the present invention is to provide a drilling device and a drilling method used in the above.

  The excavator of the present invention is an excavator for excavating a vertical hole for embedding a vertically long underground heat exchange pipe with respect to the ground, and has a structure in which an auger screw is attached to and detached from a drill head attached to a boom. Bendable connecting a mining pillar wheel, a plurality of telescopic rods attached between the drill head and the auger screw to connect them, and an uppermost telescopic rod rotatably connected to the drill head A universal joint, a coupling joint for rotatably connecting the lowermost telescopic rod and the auger screw, and an upper and lower telescopic rod for rotation, and an auger by rotating together with the telescopic rod and the auger screw. Multiple cylindrical casings that are pushed into the vertical hole while drilling the vertical hole with the screw, and the uppermost casing A rotation transmitting member that removably connects the telescopic rod, and transmits the rotation of the telescopic rod to the uppermost casing by the connection; and a rotation coupling means that rotatably connects the upper and lower casings. It is characterized by being.

This apparatus is characterized in that a chip is attached to a lower end portion of a casing located at the lowermost position among the plurality of casings.
In addition, the rotation transmission member includes an engagement groove formed in the uppermost casing, and an engagement groove in which a protruding strip extending in the axial direction is fitted on the outer surface of the telescopic rod, and is detachably engaged. The convex part is provided with the receiving recessed part which engages detachably.
Further, the rotation connecting means is formed by an engaging convex portion formed in one of the upper and lower casings, and an engaging concave portion formed in the other casing and detachably engaged with the engaging convex portion. It is characterized by being.

  According to the excavation method of the present invention, the auger screw and the expansion rod connected to the auger screw are arranged on the outer periphery of the cylindrical casing, and the expansion rod and the casing are rotated to rotate the expansion rod and the casing while pushing the casing. A first stage of drilling a vertical hole, a second stage of adding the next casing to the casing with the telescopic rod extended, and continuing to drill the vertical hole with the auger screw and casing while pushing the casing; The purpose is to repeat the third stage, the second stage, and the third stage to add the next expansion / contraction rod and add the next casing to the casing and continue drilling the vertical hole with the auger screw and casing while pushing the casing. Drilling to depth After that, the fourth stage in which the telescopic rod and the auger screw are pulled out from the vertical hole with only the casing left in the vertical hole, and after inserting the vertically long underground heat exchange pipe into the casing, the casing is removed from the vertical hole. And a fifth stage of pulling out.

According to the excavator of the present invention, the connecting joint connects the upper and lower telescopic rods and the auger screw, and the rotation transmitting member transmits the rotation of the telescopic rod to the casing, so that the casing rotates together with the auger screw. For this reason, the ground can be excavated by both the auger screw and the casing to form the vertical hole. In this excavation, since the casing is excavated with the vertical hole supported from the inside, the collapse of the vertical hole during excavation can be prevented.
In addition, since it includes a coupling joint for rotatably connecting the upper and lower telescopic rods, a rotation coupling means for rotatably coupling the upper and lower casings, and a rotation transmission member for rotatably coupling the telescopic rods and the casing. The extension of the telescopic rod and the extension of the casing can be interlocked with the excavation of the vertical hole. This improves excavation workability and enables work in a short time.

According to the excavation method of the present invention, since the vertical hole is excavated by the auger screw connected to the telescopic rod and the cylindrical casing provided on the outer periphery of the auger screw, the casing can excavate while supporting the vertical hole from the inside, The collapse of the vertical hole in the inside can be prevented by the casing. For this reason, the vertical hole is not filled with earth and sand during excavation, and the workability of inserting the underground heat exchange pipe into the vertical hole is improved. Therefore, it can be suitably applied to soft ground such as spring soil and sandy soil, and the application range can be expanded.
Moreover, since the expansion of the telescopic rod and the expansion of the casing are performed while excavating the vertical holes, the expansion and the excavation of the vertical holes can be interlocked. For this reason, the workability of excavation is improved and the work can be performed in a short time.

It is a rear view which shows the digging pillar car used for the excavation apparatus of this invention. It is a rear view which shows the preparation stage in excavation work. It is a rear view which shows the connection step to the drill head in excavation work. It is a rear view which shows the excavation operation following FIG. It is a rear view which shows the excavation operation following FIG. It is a rear view which shows the excavation operation following FIG. It is a rear view which shows the embedment work of a underground heat exchange pipe. FIG. 8 is a rear view showing the burying operation following FIG. 7. It is a side view which shows an auger screw. It is a side view which shows the shortened state of an expansion-contraction rod. It is a side view which shows the expansion | extension state of an expansion-contraction rod. It is a side view which shows a casing. It is a perspective view which shows an example of an underground heat exchange pipe. It is a perspective view which shows a underground heat exchange pipe from the lower part. It is a front view which shows a universal joint. It is a side view which shows the bending state of a universal joint. (A) is a side view which shows the connection of a universal joint and an expansion-contraction rod, (B) is an enlarged side view of the M section in (A). (A) is a side view which shows the connection of an expansion-contraction rod and an auger screw, (B) is an enlarged side view of the N section in (A). It is a perspective view which shows the male joint as a connection joint. It is a perspective view which shows the female joint as a connection joint. (A), (B) is the top view and side view which show a rotation transmission member. (A) is a side view which shows the connection state of a rotation transmission member, (B) is an enlarged side view of the P section in (A). It is a side view explaining the connection by a rotation connection means. (A), (B), (C) is a top view explaining the connection structure of a rotation transmission member and an expansion-contraction rod. It is a top view which shows a rod holder. (A), (B) is the top view and side view which show a casing holder. It is a side view which shows the structure holding an expansion-contraction rod and a casing with respect to the ground. It is a side view which shows the state which shortens an expansion-contraction rod with respect to the state of FIG.

  Hereinafter, the present invention will be specifically described with reference to an embodiment shown in the drawings. FIG. 1 is a rear view of a digging column 1 used in the excavation apparatus according to the embodiment of the present invention, and FIGS. 2 to 8 sequentially illustrate steps for digging a vertical hole 3 in the ground 2 using the digging column 1. FIG. 9 to FIG. 28 show each member used for excavation.

  As shown in FIG. 1, the excavated pillar car 1 has a boom 22 mounted on a travelable vehicle body 21, and an outrigger 23 can project from the vehicle body 21. The boom 22 is mounted on the vehicle body 21 so as to be able to undulate, extend and retract, and turn. A hanging bracket 26 for hanging a utility pole or the like is attached to the top of the boom 22. A drill head 24 is attached to the boom 22, and an auger screw 4 for excavating the ground 2 is connected to the drill head 24. In the illustrated example, a universal joint 5 to be described later is connected to the drill head 24, and a telescopic rod 6 to be described later is connected to the universal joint 5, and the auger screw 4 is connected to the drill head 24 through these. It has become a state.

As shown in FIG. 9, the auger screw 4 is provided with a helical auger blade 29 along the axial direction of the excavation shaft 28. The upper end portion of the excavation shaft 28 is a polygonal (hexagonal) male joint portion 30 connected to the telescopic rod 6 as shown in FIG. The male joint portion 30 is used not only when connecting the telescopic rod 6 but also when connecting the auger screw 4 with the universal joint 5. On the outer peripheral edge of the auger blade 29, a soil discharge plate 31 is integrally formed in a rising shape. By providing the earth removing plate 31, the earth removing amount of the auger blade 29 is increased, and the earth in the ground 2 at the time of excavation can be efficiently removed.
In addition, in a normal use state such as a utility pole standing in the digging column car 1, it is optional to use the universal joint 5 and the telescopic rod 6 in combination.

  In the excavation apparatus of this embodiment, in addition to the digging column car 1, the universal joint 5 (FIGS. 15 and 16), the plurality of telescopic rods 6 and 6a (FIGS. 10 and 11), the coupling joints 7 and 8 ( 17 to 20), a plurality of casings 9 and 10 (FIGS. 12 and 23), a rotation transmission member 11 (FIGS. 21 and 23), and a rotation connecting means 12 (FIGS. 12 and 23) are used as constituent members. It is.

The universal joint 5 is a joint member that rotatably connects the auger screw 4 and the telescopic rod (uppermost telescopic rod) 6a. As shown in FIGS. 15 and 16, in the universal joint 5, the first member 33 and the second member 34 are connected by a joint pin 35. The first member 33 is connected to the uppermost telescopic rod 6a, and a female joint portion 37 for connection is formed at the end. A polygonal (hexagonal) hole is formed in the female joint portion 37. The second member 34 is formed with a male joint portion 36 having a polygonal (hexagonal) outer shape at the end, and this male joint portion 36 is connected to the drive shaft of the drill head 24.
The first member 33 and the second member 34 are rotatable relative to each other about the joint pin 35, and the first member 33 and the second member 34 are in a straight line by this rotation (FIG. 15) and It can be displaced between the states bent at right angles (FIG. 16). In the straight line state, the first member 33 and the second member 34 are integrally rotated by the rotational force of the drill head 24. Thereby, the rotation of the drill head 24 can be transmitted to the uppermost telescopic rod 6a. In a state bent at a right angle, the telescopic rod 6 is retracted from the axis of the drill head 24. Thereby, the expansion-contraction rod 6 can be made into the state which fell on the ground 2 (refer FIG. 2).

A plurality of the telescopic rods 6 are used in a vertically connected manner, and the uppermost telescopic rod 6a and the other telescopic rods 6 have the same structure. 10 and 11 show the telescopic rod 6. The telescopic rod 6 is formed by an outer rod 38 and an inner rod 39 inserted into the outer rod 38. When the inner rod 39 is stored inside the outer rod 38, the contracted state shown in FIG. When the inner rod 39 is pulled out from the outer rod 38, the extended state shown in FIG. The outer shape of the inner rod 39 is a polygon (hexagon), and the inner portion of the outer rod 38 has a polygonal hole shape corresponding to the outer shape of the inner rod 39. As a result, the outer rod 38 and the inner rod 39 rotate together.
An insertion block 43 is provided at the lower end of the outer rod 38. The insertion block 43 is a member for inserting the inner rod 39 into the outer rod 38. The drawing length of the inner rod 39 can be adjusted by inserting the positioning pin and engaging the inner rod 39 with the inner rod 39 inserted. Further, the inner rod 39 can be pulled out by extracting the positioning pin. Thereby, expansion | extension of the expansion-contraction rods 6 and 6a can be performed adjusting in steps.

The upper end portion of the outer rod 38 is a female joint portion 40 having a polygonal hole (hexagonal hole), and the lower end portion of the inner rod 39 is a male joint portion 41 having a polygonal (hexagonal) outer shape. Therefore, the upper and lower two telescopic rods 6 can be connected by fitting the male joint portion 41 of the telescopic rod 6 located on the upper side into the female joint portion 40 of the telescopic rod 6 located on the lower side. On the outer surface of the outer rod 38, protruding ridges 42 protruding outward are formed along the axial direction. The protrusion 42 engages with an engagement groove 55 of the rotation transmission member 11 described later, and the rotation transmission member 11 and the telescopic rod 6 are connected by this engagement (see FIG. 24).

  The coupling joints 7 and 8 are for coupling the uppermost telescopic rod 6a and the universal joint 5 and for coupling the coupling rod 6 and the auger screw 4. The coupling joint 7 is a male coupling joint and the coupling joint 8 is a female coupling. It is a mold coupling joint. As shown in FIG. 19, the male coupling joint 7 has a polygonal (hexagonal) male coupling portion 7 a formed at both ends in the axial direction, and the female coupling joint 8 as shown in FIG. 20. The female joint portion 8a having a polygonal (hexagonal) hole shape is formed at both ends in the axial direction.

  As shown in FIG. 17, the male coupling joint 7 is used for coupling the universal joint 5 and the uppermost telescopic rod 6a. In this male coupling joint 7, one male joint portion 7a is fitted into the female joint portion 37 of the first member 33 of the universal joint 5, and the other male joint portion 7a is fitted into the female joint portion 40 of the uppermost extensible rod 6a. By connecting, these can be connected. After such fitting, the pin is inserted in a direction orthogonal to the axial direction to prevent it from coming off.

  The female coupling 8 is used for coupling the telescopic rod 6 and the auger screw 4 as shown in FIG. That is, one female joint 8 a is fitted into the male joint 41 of the telescopic rod 6, and the other female joint 8 a is fitted into the male joint 30 of the auger screw 4 to connect them. After the fitting, the pin is inserted in a direction orthogonal to the axial direction to prevent it from coming off.

A plurality of the casings 9 and 10 are used by being vertically connected to each other, and as shown in FIG. 12, the casings 9 and 10 are formed by a lower casing 9 located at the lowermost part and an intermediate casing 10 located at the uppermost part and in the middle. Yes. The lower casing 9 and the intermediate casing 10 have a casing body 44 having the same diameter and extending in a cylindrical shape.
A plurality of chips 45 are attached along the circumferential direction to the lower end portion of the casing body 44 in the lower casing 9 located at the lowermost portion. Thus, the lower casing 9 excavates the ground 2 together with the auger screw 4 when excavating the vertical hole 3.

Casing 9 and 10 connected up and down are mutually connected so that rotation is possible. This connection is made by the rotation connecting means 12. As shown in FIGS. 12 and 23, the rotary connecting means 12 is formed on the upper and lower casing protrusions 47 of the casing body 44 of the casing (lower) and the casing body 44 of the other (upper) casing. The engaging recess 48 is formed. The engaging convex part 47 protrudes in the shape of a rectangular block from the inner surface of the casing body 44 of one casing. The engaging concave portion 48 is formed in a rectangular concave portion that can engage with the engaging convex portion 47. When the engaging convex portion 47 engages with the engaging concave portion 48, the upper and lower casings are connected and the upper and lower casings are connected. The casing rotates integrally.
In the illustrated example, the engaging recess 48 is formed in a short cylindrical sub casing 49 extending from the casing main body 44 toward the counterpart casing, and the sub casing 49 is welded to the casing main body 44 of one casing. By fixing by bolting or the like, the engaging recess 48 is provided in the casing. The sub casing 49 is formed with an opening 50 into which the engaging convex portion 47 of the counterpart casing enters, and the engaging concave portion 48 is connected to the opening 50.

  The casing 10 positioned at the top of the plurality of casings connected in the vertical direction is connected to the telescopic rod (uppermost telescopic rod) 6a by the rotation transmission member 11, and the rotation of the telescopic rod 6a to the uppermost casing 10 by this connection. Is transmitted.

  FIG. 21 shows the rotation transmission member 11, which is formed by a transmission main body portion 52 whose bottom surface is opened and an engagement cylinder portion 53 formed in a convex shape on the upper portion of the transmission main body portion 52. The transmission main body 52 is formed with a receiving recess 54 in which an engaging projection 47 formed in the uppermost casing 10 is detachably engaged. The engaging cylinder portion 53 is formed with an engaging groove 55 into which the protrusion 42 formed on the outer surface of the outer rod 38 of the telescopic rod 6a enters and engages. As shown in FIG. 24, the rotation transmission member 11 can be opened and closed by rotating around the hinge portion 56, and the uppermost telescopic rod 6 a with respect to the open state of the rotation transmission member 11 is connected to the rotation transmission member. 11 is inserted.

As shown in FIGS. 22 and 24, the rotation transmission member 11 and the uppermost telescopic rod 6a are connected with the rotation transmission member 11 in an open state (FIGS. 22A and 22B). The telescopic rod 6a is inserted through the portion 53. At this time, the ridge 42 of the telescopic rod 6 a enters the engagement groove 55 of the rotation transmission member 11. Thereafter, the rotation transmitting member 11 is closed to engage the two protruding strips 42 of the telescopic rod 6 a with the engaging groove 55, thereby connecting the telescopic rod 6 a and the rotation transmitting member 11.
As shown in FIGS. 22 and 23, the rotation transmission member 11 and the uppermost casing 10 are connected by inserting the upper portion of the uppermost casing 10 into the transmission main body 52 with respect to the closed state of the rotation transmission member 11. This is done by rotating the engaging projection 47 of the casing 10 into the receiving recess 54 of the rotation transmitting member 11.

  In this way, the uppermost telescopic rod 6 a and the uppermost casing 10 are connected via the rotation transmitting member 11, so that the rotation of the telescopic rod 6 a is transmitted to the uppermost casing 10 via the rotation transmitting member 11. Is done. For this reason, the plurality of casings 9 and 10 coupled vertically and the plurality of telescopic rods 6a and 6 coupled vertically can rotate. As a result, the auger screw 4 attached to the telescopic rod 6 and the casing 9 positioned at the lowermost position with the bit 45 rotate together, so that the vertical hole 3 is excavated by the auger screw 4 and the lowermost casing 9. It can be performed.

  13 and 14 show an underground heat exchange pipe 20 for applying the present invention. The underground heat exchange pipe 20 has a vertically long structure and is embedded in the vertical hole 3 excavated by an embedding method described later.

The underground heat exchange pipe 20 of this embodiment forms a flow path through which a heat medium such as water or antifreeze flows by a spiral heat exchange pipe 61. In the spiral heat exchange pipe 61, an introduction pipe part 62 into which a heat medium is introduced and a lead-out pipe part 63 that supplies the heat medium to a ground load device are drawn out from both ends of the flow path. The spiral heat exchange tube 61 is formed so as to be wound around a frame rod 64 extending in the vertical direction. A weight plate 65 for smoothly inserting into the vertical hole 3 by weight is attached to the lower end portion of the frame rod 64. Further, an air pipe 66 is inserted into the heat exchange pipe 61. The lower end portion of the air pipe 66 penetrates the weight plate 65, and the penetrated end portion serves as a jet outlet 67 for jetting air (compressed air). Thereby, since air can be ejected toward the bottom of the vertical hole 3, it acts so that the muddy water that has flowed into the vertical hole 3 is stirred, and the underground heat exchange pipe 20 is smoothly fed into the vertical hole 3. be able to.
As the underground heat exchange pipe 20, a structure other than the spiral structure can be applied as long as it is a vertically long structure.

Next, excavation work for burying the underground heat exchange pipe 20 will be described with reference to FIGS. 2 to 8 and FIGS. 25 to 28. Excavation work is done in the following stages.
First stage: The telescopic rod 6a and the casing with the cylindrical casing (lowermost casing) 9 disposed on the outer periphery of the auger screw 4 and the telescopic rod (uppermost telescopic rod) 6a to which the auger screw 4 is connected. The vertical hole 3 is excavated in the ground 2 by the auger screw 4 and the casing 9 while pushing the casing 9 by rotating the 9.
Second stage: The next casing (intermediate casing) 10 is added to the casing 9 with the telescopic rod 6a extended, and the vertical hole 3 is excavated by the auger screw 4 and the casings 9, 10 while pushing the casings 9, 10. continue.
Third stage: The next expansion / contraction rod 6 is added to the expansion / contraction rod 6 a and the next casing (intermediate casing) 10 is added to the casing 10. Continue drilling 3
After the fourth stage and the second stage and the third stage are dug to the target depth, only the casings 9 and 10 are left in the vertical hole 3, and the telescopic rods 6 a and 6 and the auger screw 4 are placed in the vertical hole 3. Pull out from.
Fifth stage: After the vertically long underground heat exchange pipe 20 is inserted into the casings 9 and 10, the casings 9 and 10 are pulled out from the vertical holes 3.

  FIG. 2 shows a preparation stage for drilling a vertical hole. Although illustration is omitted, the telescopic rod 6a is connected to the rear side (left side) of the male connecting joint 7 in FIG. 2, and the auger screw 4 is connected to the connecting rod 6a. Further, a casing 9 is disposed on the outer periphery of the telescopic rod 6 a via a rotation transmission member 11. The male coupling joint 7 is coupled to the drill head 24 via the universal joint 5, but the universal joint 5 is bent at this preparation stage. Therefore, the male connecting member 7 can be connected to the universal joint 5 while the male connecting joint 7, the telescopic rod 6a, the auger screw 4 and the casing 9 following the male connecting joint 7 are placed on the ground 2. There is no need to lift, hold, or move heavy objects, and connection work can be easily performed. By pushing up the boom 22 in this state, the state shifts to the excavable state shown in FIG.

  FIG. 3 shows the state of the first stage. In FIG. 3, the auger screw 4, the telescopic rod 6 a and the casing 9 are erected with respect to the ground 2 by the boom 22, and the drill head 22 is driven while pushing down the boom 22. As a result, the telescopic rod 6 a rotates and the auger screw 4 and the casing (the lowermost casing) 9 rotate, so that the vertical hole 3 is excavated in the ground 2 by the auger screw 4 and the casing 9. Thereafter, the excavation is stopped, the rotation transmitting member 11 is removed, and the telescopic rod 6a and the auger screw 4 are pulled up and discharged. By repeating this excavation and soil removal, the vertical hole 3 is excavated to a predetermined depth.

  FIG. 4 shows the state of the second stage. The telescopic rod 6a is extended with the rotation transmitting member 11 removed in the first stage, and the connection between the telescopic rod 6a and the drill head 24 is disconnected. Then, a casing (intermediate casing) 10 of the next stage is added to the casing 9 via the rotation coupling means 12, and the rotation transmission member 11 is attached to the upper part of the intermediate casing 10. Further, the drill head 24 and the telescopic rod 6 a are connected by the universal joint 5. Thereafter, the drill head 24 is driven while the boom 22 is pushed down to rotate the telescopic rod 6a, whereby the auger screw 4 and the casing (lowermost casing) 9 are rotated together to excavate the ground 2. This excavation and the above-described soil removal are repeated.

FIG. 5 shows the state of the third stage. In the third stage, after disconnecting the connection between the drill head 24 and the telescopic rod 6a, the rotation transmission member 11 is removed, and the second stage (second) telescopic rod 6 is added to the telescopic rod 6a. Further, a casing (intermediate casing) 10 of the next stage is added to the casing 10 via the rotary connecting means 12. Then, after attaching the rotation transmission member 11 to the casing 10 at the next stage, the second telescopic rod 6 is connected to the drill head 24.
Thereafter, the drill head 24 is driven while the boom 22 is pushed down to rotate the telescopic rods 6 a and 6, and the excavation of the vertical hole 3 with respect to the ground 2 is continued by the auger screw 4 and the casing 9. The vertical hole 3 is excavated to the target depth by repeating such excavation and soil removal.

  In the second and third stages described above, the lowermost casing 9 excavates the ground 2 together with the auger screw 4. For this reason, excavation can be performed with the casings 9 and 10 supporting the vertical holes 3 from the inside, and the collapse of the vertical holes 3 during excavation can be prevented by the casings 9 and 10. Thereby, the vertical hole 3 is not filled with earth and sand during excavation. Further, since the expansion of the telescopic rods 6a and 6 and the addition of the casings 9 and 10 are performed while excavating the vertical hole 3, the expansion and the excavation of the vertical hole 3 can be interlocked. As a result, workability of vertical hole excavation is improved, and work in a short time becomes possible.

  FIG. 6 shows the state of the fourth stage. In the fourth stage, the telescopic rods 6a and 6 are pulled out from the vertical hole 3 and the auger screw 4 is pulled out from the vertical hole 3. By pulling out the telescopic rods 6 a and 6 and the auger screw 4, only the added casings 10 and 9 are left in the vertical hole 3. Since the remaining casings 10 and 9 hold the state in which the vertical hole 3 is supported from the inside, the vertical hole 3 is not inadvertently collapsed.

  In the fourth stage, the rotation transmitting member 11 is removed and the telescopic rod 6 is pulled out on the ground 2. At this time, as shown in FIGS. 27 and 28, the casing holder 57 (FIG. 26) is fixed to the head of the casing 10 extracted from the vertical hole 3 to prevent the casing 10 from falling into the vertical hole 3. . Further, the rod holder 13 (FIG. 25) is supported on the head of the casing 10. The rod holder 13 holds the extended telescopic rod 6 and prevents it from falling into the vertical hole 3.

  As shown in FIG. 25, the rod holder 13 includes a pair of holder arms 14 and 14 that can be opened and closed, and a lock bar 15 that connects the holder arms 14 and 14. The rod holder 13 sandwiches the telescopic rod 6 by sandwiching the telescopic rod 6 between a pair of holder arms 14 and 14 and fixing the holder arms 14 and 14 by a lock bar 15.

  As shown in FIG. 26, the casing holder 57 is configured to hold the casing 10 by sandwiching the casing 10 between the first holder 58 and the second holder 59. A plurality of contact pieces 60 are formed on the inner surfaces of the first holder 58 and the second holder 59 on the circumference, and the contact pieces 60 are in contact with the outer surface of the casing 10. The abutment piece 60 and the casing 10 are welded together to couple with the casing 10. On the other hand, by removing the welded portion of the contact piece 60, the holding of the casing 10 by the casing holder 57 is released. The contact piece 60 and the casing 10 can be coupled by a bolt or the like.

  The extraction of the telescopic rod 6 and the auger screw 4 in the fourth stage is performed by shortening the upper (second) telescopic rod 6 while the telescopic rod 6 is held by the rod holder 13, as shown in FIGS. Remove the second telescopic rod 6. Then, the drill head 24 and the lower (first) telescopic rod 6 are connected, the rod holder 13 is removed, the first telescopic rod 6 is pulled out, and the rod 6 is shortened. In this state, the telescopic rod 6 and the auger screw 4 are pulled out from the casing 10. Thereafter, the telescopic rod 6 and the auger screw 4 are separated and the telescopic rod 6 and the drill head 24 are separated. As a result, only the added casings 9 and 10 are left in the vertical hole 3.

  7 and 8 show the state of the fifth stage. First, as shown in FIG. 7, the underground heat exchange pipe 20 is suspended by the suspension bracket 26 and moved onto the vertical hole 3, and the boom 22 is pushed down to push the underground heat exchange pipe 20 into the vertical hole 3. At the time of this pushing, air is ejected from the ejection port 67 of the air pipe 66 toward the bottom of the vertical hole 3. Even if muddy water is springing up in the vertical hole 3 due to the ejection of air, the air stirs it, so the resistance of the muddy water is reduced and the underground heat exchange pipe 20 can be pushed in smoothly.

FIG. 8 shows the operation following FIG. In this operation, the casings 9 and 10 left in the vertical holes 3 are pulled out. The casings 9 and 10 are pulled out by connecting the rotation transmitting member 11 attached to the uppermost casing 10 and the drill head 24 via the universal joint 5 and pushing up the boom 22 while rotating the drill head 24. The casing 10 is pulled out from the vertical hole 3. The same applies to the pulling out of the casing 10 following the lower side. The rotation transmitting member 11 is attached to the next casing 10, the rotation transmitting member 11 is connected to the drill head 24, and the boom 22 is pushed up while rotating the drill head 24. Pull out. By repeating this, all the casings 9 and 10 are pulled out from the inside of the vertical hole 3.
After all the casings 9 and 10 have been pulled out, the vertical holes 3 are backfilled with soil, thereby completing the underground heat exchange pipe 20 embedding.

According to the excavator described above, the coupling joints 7 and 8 connect the upper and lower telescopic rods 6 a and 6 and the auger screw 4, and the rotation transmission member 11 transmits the rotation of the telescopic rods 6 a and 6 to the casings 9 and 10. Therefore, the casings 9 and 10 rotate with the auger screw 4 to excavate the vertical hole 3. In such excavation, since the casings 9 and 10 excavate in a state where the vertical holes 3 are supported from the inside, the vertical holes 3 can be prevented from collapsing during excavation.
Further, the coupling joints 7 and 8 for connecting the upper and lower telescopic rods 6a and 6 rotatably, the rotary connecting means 12 for connecting the upper and lower casings 9 and 10 rotatably, the telescopic rods 6a and 6 and the casings 9 and 10 Since the rotation transmission member 11 is rotatably connected, the extension of the telescopic rods 6a and 6 and the addition of the casings 9 and 10 can be linked to the excavation of the vertical hole 3, so that the work of the vertical hole excavation can be performed. Therefore, the work can be performed in a short time.

According to the excavation method described above, the vertical hole 3 is excavated by the auger screw 4 connected to the telescopic rods 6 a and 6 and the casings 9 and 10 provided on the outer periphery of the auger screw 4. Can be excavated while being supported from the inside, preventing the vertical hole 3 from collapsing. For this reason, the vertical hole 3 is not buried with earth and sand during excavation, and the workability of inserting the underground heat exchange pipe 20 into the vertical hole 3 is improved. For this reason, it can be applied not only to soft ground such as spring soil and sandy soil, but also to various grounds such as cohesive soil and gravelly soil, and the application range can be expanded.
Moreover, since the expansion rods 6a and 6 are added while the vertical holes 3 are excavated and the casings 9 and 10 are added, the addition and the excavation of the vertical holes 3 can be linked to improve the workability of the vertical hole excavation. And can work in a short time.

DESCRIPTION OF SYMBOLS 1 ... Hole digging pillar wheel, 2 ... Ground, 3 ... Vertical hole, 4 ... Auger screw, 5 ... Universal joint, 6, 6a ... Telescopic rod, 7, 8 ... Connection joint, 9, 10 ... Casing, 11 ... Transmission of rotation Member: 12 Rotating connection means, 20: Underground heat exchange pipe, 22: Boom, 24 ... Drill head, 29 ... Auger blade, 38 ... Outer rod, 39 ... Inner rod, 42 ... Projection, 47 ... Engaging projection 48, engaging recess, 54 ... receiving recess, 55 ... engaging groove

Claims (5)

A drilling device that drills a vertical hole for burying a vertically long underground heat exchange pipe into the ground,
An excavated pillar car with a structure in which an auger screw is attached to and detached from a drill head attached to the boom,
A plurality of telescopic rods of a telescopic structure attached between the drill head and the auger screw and connecting them;
A bendable universal joint that rotatably connects the top telescopic rod to the drill head;
A coupling joint that rotatably couples the lowermost telescopic rod and the auger screw and also couples the upper and lower telescopic rods together,
A plurality of cylindrical casings that are pushed into the vertical hole while excavating the vertical hole together with the auger screw by rotating together with the telescopic rod and the auger screw;
A rotation transmitting member for detachably connecting the uppermost casing and the telescopic rod, and transmitting the rotation of the telescopic rod to the uppermost casing by the connection;
Rotary connecting means for rotatably connecting the upper and lower casings;
A drilling rig characterized by comprising:   The excavator according to claim 1, wherein a tip is attached to a lower end portion of a casing located at a lowermost portion of the plurality of casings.   The rotation transmission member includes an engagement groove that is engaged with a protrusion extending along the axial direction on the outer surface of the telescopic rod and engages detachably, and an engagement protrusion formed on the uppermost casing. The excavator according to claim 1, further comprising a receiving recess that is detachably engaged.   The rotation connecting means is formed by an engaging convex portion formed in one of the upper and lower casings, and an engaging concave portion formed in the other casing and detachably engaged with the engaging convex portion. The excavator according to any one of claims 1 to 3. A first excavation of a vertical hole in the ground by the auger screw and the casing while the casing is pushed in by rotating the expansion rod and the casing while the cylindrical casing is disposed on the outer periphery of the auger screw and the expansion rod connected to the auger screw. Stages,
A second stage in which the next stage casing is added to the casing with the telescopic rod extended, and the drilling of the vertical hole is continued with the auger screw and the casing while pushing the casing;
A third stage in which the next-stage expansion rod is added to the expansion-contraction rod and the next-stage casing is further added to the casing, and the excavation of the vertical hole by the auger screw and the casing is continued while pushing the casing;
After digging to the target depth by repeating the second step and the third step, the fourth step of pulling out the telescopic rod and the auger screw from the vertical hole while leaving only the casing in the vertical hole;
A fifth step of inserting a vertically long underground heat exchange pipe into the casing and then pulling out the casing from the inside of the vertical hole.

Images