JP5873679B2 - Drilling bucket and excavation method using drilling bucket - Google Patents

Description

  The present invention relates to a drilling bucket used in an earth drill method and a drilling method using the drilling bucket.

  When constructing cast-in-place concrete piles, the ground may be excavated by the earth drill method. In the earth drill method, the drilling bucket is rotated while pressed against the bottom wall of the excavation hole, the excavation soil is taken into the bucket while the ground is being cut, and the taken-in sediment is discharged repeatedly, thereby excavating the excavation hole. Is drilled to the desired depth.

  Since the drilling bucket has a structure for taking in earth and sand from the bottom thereof, in order to take in new earth and sand, it is necessary to push up the earth and sand already taken into the drilling bucket. However, when the earth and sand taken into the drilling bucket reach a predetermined height, the force for pushing up the earth and sand and the pressing force due to the weight of the inner earth and sand are in balance, and no more earth can be taken in. The amount of earth and sand at this time is the maximum excavation amount of the drilling bucket once, depending on the nature of the earth and sand to be excavated, the force to press the drilling bucket against the bottom wall of the drilling hole (pushing force), the rotational force of the drilling bucket Determined.

  When the sediment in the drilling bucket reaches the maximum excavation amount, the drilling bucket is pulled up to the ground, and the sediment in the drilling bucket is discharged to the outside of the excavation hole, and then the drilling bucket is inserted into the excavation hole again. When the drilling bucket is raised and lowered, the stabilizing liquid in the excavation hole is agitated. This causes a problem that the skin of the hole wall is peeled off, and the hole wall that has been skinned is deposited on the bottom of the hole and slime is generated. Accordingly, it is desirable that the number of times the drilling bucket is raised and lowered is small.

  Furthermore, if the number of times of raising and lowering the drilling bucket is small, the time required for raising and lowering the drilling bucket is shortened, and the working time of the entire excavation work can be shortened.

  In order to reduce the number of times the drilling bucket is moved up and down, it is necessary to increase the maximum excavation amount of the drilling bucket once. To that end, it is only necessary to increase the pushing force and rotational force of the drilling bucket, but there is a problem that the driving device for driving the drilling bucket becomes an excessive facility.

  Patent Document 1 describes a technique for increasing the maximum excavation amount of one drilling bucket without increasing the pushing force and the rotational force. In this technology, an auger screw is installed in the drilling bucket, and the earth and sand taken in the drilling bucket is transported upward by the auger screw, so that the earth and sand can be taken up to the upper part of the long bucket. Is.

Japanese Patent Laid-Open No. 02-128091

  However, in the technique described in Patent Document 1, the auger screw is rotated in the reverse direction by reversing the rotational force of the drilling bucket that rotates in the forward direction with the rotation of the coupled kelly bar by the power conversion mechanism. Therefore, there is a problem that a complicated power conversion mechanism is required.

  In view of the above points, the present invention provides a drilling bucket capable of increasing the maximum excavation amount per time without requiring an excessive drive device or a complicated power conversion mechanism, and excavation using the drilling bucket. It aims to provide a method.

The drilling bucket of the present invention is a drilling bucket that takes excavated earth and sand into the bucket, and includes a main body bucket and an internal container that is built in the main body bucket and configured to be movable up and down in the main body bucket. The main body bucket includes a cylindrical bucket body portion, a bucket bottom lid provided at the bottom of the bucket body portion so as to be openable and closable, and a bucket opening formed in the bucket bottom lid, and the internal container includes: A cylindrical container body portion having a smaller diameter than the bucket body portion, a container bottom lid provided at the bottom of the container body portion so as to be openable and closable, and a container opening formed in the container bottom lid, in the state in which the interior of the container is located at the lowest position, before when rotating the bucket bottom cover in a state pressed against the bottom wall of the borehole Wherein the guide plate is provided to induce sediment taken from the bucket opening to the container opening.

  The inner container being positioned at the lowest position means that the inner container is positioned at the lowest position within the range in which the main body bucket can be raised and lowered. By excavating with the internal container in this position, the earth and sand taken in from the bucket opening can be taken into the internal container from the container opening via the guide plate.

  According to the drilling bucket of the present invention, in the state where the inner container is located at the lowest lowered position, the earth and sand can be taken into the inner container through the bucket opening, the guide plate, and the container opening, and the inner container In the raised state, earth and sand can be taken into the main body bucket through the bucket opening. Therefore, when the same drive device as the drive device for driving the conventional drilling bucket is used, both the inner container and the main body bracket can take the earth and sand up to the same height as the conventional one. It is possible to increase the maximum excavation amount.

  As a result, the number of times the drilling bucket is raised and lowered can be reduced, and it is possible to reduce the skin fall of the hole wall and the generation of slime.

  Furthermore, it is the structure which added only the internal container and guide plate which were comprised so that raising / lowering was possible in a main body bucket with respect to the conventional drilling bucket. Therefore, a complicated power transmission mechanism as in the technique described in Patent Document 1 is not required.

  And it is possible to take the earth and sand into the inner container and the main body bracket to the same predetermined height determined by the driving force of the driving device. Therefore, the length of the body portion of the inner container and the length of the body portion between the bucket bottom lid and the inner container bottom portion in the state where the inner container of the main body bucket is raised should be equal to or greater than the predetermined intake height. For example, one maximum excavation amount can be maximized.

  Therefore, in the drilling bucket of the present invention, it is preferable that the length of the bucket body is at least twice as long as the length of the container body.

  The mechanism that allows the inner container to move up and down in the main body bucket is not limited. For example, a hydraulic cylinder may be used.

  In this case, in the drilling bucket of the present invention, the bucket body part and the container body part are connected via a hydraulic cylinder, and the inner container moves up and down in the main body bucket by expansion and contraction of the hydraulic cylinder. It is preferable. Thereby, the mechanism can be configured easily. The hydraulic cylinder may be operated by a hydraulic mechanism or the like installed on the ground.

  Further, the mechanism may be realized by a force transmitted via a kelly bar that transmits a rotational force and a lifting force to the drilling bucket.

  In this case, in the drilling bucket of the present invention, a kerry bar is connected to an upper portion of the inner container, the inner container is moved up and down in the main body bucket by power via the kelly bar, and the inner container is passed through the kelly bar. It is also preferable to provide a transmission mechanism that transmits the power transmitted to the main body bucket to raise and lower the main body bucket and rotate it. This eliminates the need for another power source.

  The excavation method of the present invention is an excavation method for excavation holes using a drilling bucket comprising a main body bucket and an internal container built in the main body bucket and configured to be movable up and down in the main body bucket. A step of inserting the drilling bucket into the excavation hole in a state where the container is located at the lowest position, and rotating the drilling bucket against the bottom wall of the excavation hole to form at the bottom of the main body bucket The earth and sand taken in from the bucket opening is taken into the inner container from the container opening formed at the bottom of the inner container via a guide plate, and the rotation of the drilling bucket is stopped. A step of moving the inner container in which the earth and sand are taken up to the bottom, and pushing the drilling bucket against the bottom wall of the excavation hole. Rotating in the attached state, taking the earth and sand from the bucket opening into the space formed inside the main body bucket by moving the internal container upward, and stopping the rotation of the drilling bucket And discharging the earth and sand taken into the main body bucket and the inner container to the outside of the excavation hole.

  According to the excavation method of the present invention, similarly to the effect of the drilling bucket of the present invention, even when the same drive unit as the conventional one is used, the maximum excavation amount per time is increased as compared with the conventional one. Is possible. Therefore, the number of times of raising and lowering the drilling bucket can be reduced, and it is possible to reduce the skin fall of the hole wall and the generation of slime.

Sectional drawing which shows the state which lowered | hung the drilling bucket which concerns on the 1st Embodiment of this invention to the bottom wall of an excavation hole. Sectional drawing along the II-II line of FIG. The bottom view of a drilling bucket. FIG. 2 is a cross-sectional arrow view taken along line IV-IV in FIG. 1. Sectional drawing along the VV line of FIG. Sectional drawing which shows the state which located the inner container of the drilling bucket in the highest position. Sectional drawing which shows the state which dropped the drilling bucket which concerns on the 2nd Embodiment of this invention to the bottom wall of a digging hole.

  The drilling bucket according to the present invention includes a main body bucket (long bucket) longer than a general drilling bucket and an internal container (internal bucket) built in the main bucket, and the internal container can move up and down in the main body bucket. It is configured as follows.

[First Embodiment]
Hereinafter, a drilling bucket 100 according to a first embodiment of the present invention will be described with reference to FIGS. 1 to 6. The drilling bucket 100 uses a hydraulic cylinder 30 as a mechanism that allows the inner container 20 to move up and down within the main body bucket 10.

  The main body bucket 10 includes a cylindrical body portion (bucket body portion) 11 and a substantially conical bottom lid (bucket bottom lid) 12 which is disposed on the bottom portion of the body portion 11 so as to be freely opened and closed and protrudes downward. Yes. The bottom lid 12 is formed with two openings (bucket openings) 13 for taking earth and sand into the main body bucket 10 (see FIG. 3). A blade edge (cutting blade) 14 (see FIG. 3) is provided at a portion of the bottom lid 12 that contacts the bottom wall of the excavation hole A.

  By rotating the bottom lid 12 while pressing the bottom lid 12 against the bottom wall of the excavation hole A, the earth and sand cut by the blade edge 14 is taken into the main body bucket 10 through the opening 13. The pushing force and rotational force of the drilling bucket 100 are transmitted from the kelly bar 40.

  The internal container 20 includes a cylindrical body part (container body part) 21 and an openable and closable arrangement at the bottom of the body part 21, and includes a flat bottom cover (container bottom cover) 22. The outer diameter of the body portion 21 is smaller than the inner diameter of the body portion 11 of the main body bucket 10. Two openings (container openings) 23 for taking in earth and sand are formed in the bottom lid 22 of the internal container 20 (see FIG. 4).

  Further, the drilling bucket 100 is provided with a slope-shaped guide plate 50 for guiding the earth and sand taken from the opening 13 of the main body bucket 10 to the opening 23 of the internal container 20. Here, the guide plate 50 is provided on the bottom cover 12 of the main body bucket 10 here, but may be provided on the bottom cover 22 of the internal container 20.

  The main body bucket 10 and the bottom lids 12 and 22 of the inner container 20 are supported by the trunk portions 11 and 21 by hinges 15 and 25, respectively, so that they can be opened and closed. Locking mechanisms (hook mechanisms) 16 and 26 are provided as mechanisms for maintaining the bottom lids 12 and 22 closed below the body portions 11 and 21, respectively.

  By releasing the locking of the bottom lids 12 and 22 by the locking mechanisms 16 and 26, the bottom lids 12 and 22 rotate downward with the hinges 15 and 25 as fulcrums, and the lower portions of the body portions 11 and 21 are exposed to the outside. Opened. When opening the main lid 10 and the bottom lids 12 and 22 of the internal container 20, it is preferable to dispose these hinges 15 and 25 so that the bottom lids 12 and 22 do not interfere with each other. The locking mechanisms 16 and 26 are unlocked when an operator operates a hook operation rod (not shown) or the like.

  Each opening 23 of the inner container 20 is provided with a check plate (shutter plate) 27. The check plates 27 are swingably provided on the hinges 28, respectively. Since the opening 23 is closed by the check plate 27 to prevent the sediment from falling, the sediment once taken into the internal container 20 does not flow back into the main body bucket 10. Although not shown, each opening 13 of the main body bucket 10 is also provided with a check plate.

  The inner container 20 is configured to be movable up and down by two hydraulic cylinders 30 installed in the main body bucket 10. Each hydraulic cylinder 30 has a cylinder base connected to an upper surface plate 11 b fixed to the upper surface of the body portion 11 of the main body bucket 10, and a rod tip connected to a lower portion of the body portion 21 of the internal container 20. Although not shown, the hydraulic cylinder 30 expands and contracts by hydraulic pressure supplied from a hydraulic device installed on the ground.

  The kelly bar 40 is connected to the center of the upper end of the main body bucket 10 using a connecting pin 41. Specifically, the connecting portion 17 provided at the center portion of the upper surface plate 11 b fixed to the upper surface of the body portion 11 of the main body bucket 10 and the lower end portion of the kelly bar 40 are connected using the connecting pin 41. Yes. Thereby, the kelly bar 40 and the main body bucket 10 are integrated, and the pushing force and the rotational force when the drilling bucket 100 is excavated are directly transmitted from the kelly bar 40 to the main body bucket 10.

  Although not illustrated, the upper end of the kelly bar 40 is suspended from a heavy machine such as a crane via a wire, and the middle part thereof is connected to a driving device such as a hydraulic motor installed in the heavy machine. The kelly bar 40 is configured to be rotatable by a driving force from a driving device.

  In addition, if the main body bucket 10 and the inner container 20 rotate independently, torsional stress will act on the hydraulic cylinder 30, which is not preferable. Therefore, a mechanism for transmitting the rotational force from the main body bucket 10 to the internal container 20 is provided.

  Here, as such a mechanism, a groove portion 11a extending in the vertical direction is provided inside the trunk portion 11 of the main body bucket 10, and a protruding portion 21a that is fitted to the groove portion 11a is provided outside the trunk portion 21 of the internal container 20. ing. Thereby, the rotational force of the main body bucket 10 can be transmitted to the inner container 20 without restricting the raising and lowering of the inner container 20, and the inner container 20 rotates in the same manner as the main body bucket 10 rotates.

  Furthermore, although not shown, it is preferable to surround the entire hydraulic cylinder 30 or a part thereof with a protective member in order to prevent the hydraulic cylinder 30 from being covered with earth and sand and hindering the elevation of the internal container 20. The protective member may be, for example, a flexible tube that can be stretched or a bellows-like sheet. Further, the above-described mechanism for transmitting the rotational force from the main body bucket 10 to the inner container 20 may be provided in the protective member.

  Next, the excavation method using the drilling bucket 100 will be described.

  [1] First, with the internal container 20 positioned at the lowest position, the heavy machinery is operated to insert the drilling bucket 100 into the excavation hole A, and attach the drilling bucket 100 to the bottom wall of the excavation hole A. Let the bottom.

  The state in which the inner container 20 is positioned at the lowest position means a state in which the inner container 20 is positioned at the lowest position within the range in which the main body bucket 10 can be raised and lowered. By excavating in this state, the earth and sand taken in from the opening 13 can be taken into the inner container 20 from the opening 23 via the guide plate 50.

  [2] The driving device is operated to lower the drilling bucket 100 while rotating the kelly bar 40. Then, the drilling bucket 100 is rotated while pressed against the bottom wall of the excavation hole A. Thereby, the earth and sand cut by the blade edge 14 is taken in from the opening part 13 of the main body bucket 10. At this stage, the earth and sand taken in from the opening 13 of the main body bucket 10 is pushed up by the earth and sand taken in subsequently, and taken into the internal container 20 through the opening 23 via the guide plate 50.

  [3] When the earth and sand in the internal container 20 reaches the maximum intake amount of the internal container 20 once, the operation of the driving device is stopped and the rotation of the drilling bucket 100 is stopped. And the said hydraulic mechanism is operated, and as shown in FIG. 6, the hydraulic cylinder 30 is retracted and the internal container 20 is raised to the highest position. As the internal container 20 is raised, a space is formed in the lower part of the main body bucket 10.

  The state in which the inner container 20 is located at the highest position means a state in which the inner container 20 is located at the highest position within the range in which the main body bucket 10 can be raised and lowered. By excavating in this state, earth and sand can be taken into the main body bucket 10 from the opening 13 to the maximum extent.

  [4] Thereafter, the driving device is operated again to rotate the drilling bucket 100 while being pressed against the bottom wall of the excavation hole A. Thereby, earth and sand are taken in in the space formed in the lower part of the main body bucket 10 by the raising of the internal container 20.

  [5] When the earth and sand in the main body bucket 10 reaches the maximum intake amount of the main body bucket 10 once, the operation of the driving device is stopped and the rotation of the drilling bucket 100 is stopped.

  [6] Operate the heavy machinery to lift the drilling bucket 100 to the ground. And the earth and sand taken in the inside of the inner container 20 and the main body bucket 10 are discharged | emitted outside the excavation hole A. FIG.

  For discharging the earth and sand, first, the bottom cover 12 of the main body bucket 10 is opened to drop the earth and sand. Next, the hydraulic mechanism is operated to extend the hydraulic cylinder 30 and move the internal container 20 to the lowest position, and then the bottom cover 22 is opened to drop the earth and sand. If earth and sand are stuck inside the main body bucket 10, the inner container 20 is lowered after scraping off such earth and sand.

  After all the earth and sand have been discharged, the bottom lid 22 of the inner container 20 is closed, and then the bottom lid 12 of the main body bucket 10 is closed. Since the positional relationship between the main body bucket 10 and the inner container 20 in the rotational direction is constant, the respective opening portions 13 and 23 and the guide plate 50 are positioned suitable for taking in earth and sand by closing the respective bottom lids 12 and 22. Become a relationship.

  The operations [1] to [6] are repeated until the excavation hole A reaches a desired depth.

  Thus, the maximum excavation amount of the drilling bucket 100 once is the sum of the maximum intake amount of the main body bucket 10 and the maximum intake amount of the internal container 20 of one time.

  Both the main body bucket 10 and the inner container 20 have the same height as that of a normal drilling bucket in which soil and sand can be taken up and pushed up. Therefore, when the same drive unit as the normal drilling bucket is used, the body part 11 of the main body bucket 10 is about twice as long as the body part of the normal drilling bucket, and the body part 21 of the internal container 20 is used as the normal drilling bucket. If the inner container 20 is configured to be able to rise to the central portion of the main body bucket 10 or more, the drilling bucket 100 will have the largest excavation amount and the highest work efficiency. .

  As described above, in the state where the internal container 20 is positioned at the lowest lowered position, earth and sand can be taken into the internal container 20 through the opening 13, the guide plate 50, and the opening 23, and the internal container In the state where it is located at the highest position, earth and sand can be taken into the main body bucket 10 through the opening 13.

  Therefore, when the same drive device as the drive device that drives the conventional drilling bucket is used, both the inner container 20 and the main body bucket 10 can take up the soil to the same height as the conventional one. Therefore, even when the same drive unit as in the conventional case is used, it is possible to increase the maximum excavation amount per time as compared with the conventional case.

  As a result, the number of times the drilling bucket 100 is raised and lowered can be reduced, and the skin from the hole wall and the occurrence of slime can be reduced.

  Furthermore, it is the structure which only added the internal container 20 and the guide plate 50 comprised so that raising / lowering was possible in the main body bucket 10 with respect to the conventional drilling bucket. Therefore, a complicated power transmission mechanism as in the technique described in Patent Document 1 is not required.

  And it is possible to take in the earth and sand to the main body bucket 10 and the internal container 20 to the predetermined | prescribed same height defined by the driving force of a drive device. Therefore, the height of the internal space in which the earth and sand of the main body bucket 10 when the internal container 20 is located at the highest position and the length of the body portion 21 of the internal container 20 are both equal to or greater than the predetermined intake height. Then, the maximum excavation amount per time can be maximized. Therefore, the length of the body portion 11 of the main body bucket 10 is preferably at least twice as long as the length of the body portion 21 of the internal container 20.

[Second Embodiment]
Hereinafter, a drilling bucket 200 according to a second embodiment of the present invention will be described with reference to FIG. The drilling bucket 200 uses a force transmitted to the kelly bar 40 by a mechanism capable of moving the inner container 20 up and down in the main body bucket 10. In addition, about the structure similar to the drilling bucket 100, the same code | symbol is used and the description is abbreviate | omitted.

  The kelly bar 40 is connected to the center of the upper end of the inner container 20 using a connecting pin 41. Specifically, the connecting portion 62 provided at the center of the upper surface plate 61 fixed to the upper surface of the body portion 21 of the inner container 20 and the lower end portion of the kelly bar 40 are connected using the connecting pin 41. Yes. Thereby, the Kelly bar 40 and the inner container 20 are integrated.

  The pushing force and rotational force from the kelly bar 40 during excavation are configured to be transmitted to the main body bucket 10 via the internal container 20. Specifically, the inner container 20 is formed by forming the groove 63 on the inner side of the body portion 11 of the main body bucket 10 and fitting the protruding portion 64 formed on the outer side of the body portion 21 of the inner container 20 into the groove portion 63. Only the movement along the groove 63 with respect to the main body bucket 10 is possible.

  The groove portion 63 includes a vertical groove portion 63a formed in the vertical direction for raising and lowering the inner container 20, and two horizontal groove portions 63b and 63c extending in the horizontal direction in the same direction starting from upper and lower ends of the vertical groove portion 63a. As a whole, it is U-shaped.

  When the protruding portion 64 of the inner container 20 abuts on the front ends of the horizontal groove portions 63b and 63c, the inner container 20 applies a rotational force and a pushing force toward the front end from the start ends of the horizontal groove portions 63b and 63c to the main body bucket 10. It is possible to transmit from 20 to the main body bucket 10.

  The lower horizontal groove 63b is set so that the lower end of the inner container 20 is at the lowest lowered position which is the height near the lower end of the main body bucket 10. When the protruding portion 64 of the main body bucket 10 is positioned at the tip of the lower horizontal groove portion 63b, the earth and sand taken in from the opening portion 13 of the main body bucket 10 passes through the guide plate 50 from the opening portion 23 to the inner container 20. Can be taken in.

  The upper horizontal groove 63c is set so that the upper end of the inner container 20 is at the highest position that is the height near the upper end of the main body bucket 10. When the internal container 20 is located at the highest position, the main body bucket 10 can take up the earth and sand up to the maximum take-up amount of one time.

  Next, an excavation method using the drilling bucket 200 will be described.

  [1] First, with the internal container 20 positioned at the lowest position, the heavy machinery is operated to insert the drilling bucket 200 into the excavation hole A, and attach the drilling bucket 200 to the bottom wall of the excavation hole A. Let the bottom.

  [2] The driving device is operated to lower the drilling bucket 200 while rotating the kelly bar 40. Then, the drilling bucket 200 is rotated while pressed against the bottom wall of the excavation hole A. Thereby, the cut earth and sand are taken in from the opening 13 of the main body bucket 10. At this stage, the earth and sand taken in from the opening 13 of the main body bucket 10 is pushed up by the earth and sand taken in subsequently, and taken into the internal container 20 through the opening 23 via the guide plate 50.

  [3] When the earth and sand in the internal container 20 reaches the maximum intake amount of the internal container 20 once, the operation of the driving device is stopped and the rotation of the drilling bucket 200 is stopped. Then, the driving device is operated to reversely rotate the kelly bar 40 so that the protruding portion 64 of the main body bucket 10 is positioned at the start end of the lower horizontal groove portion 63b (that is, the lower end of the vertical groove portion 63a), and then the driving Deactivate the equipment.

  Then, the lifting machine is operated to raise the kelly bar 40 so that the protruding portion 64 of the main body bucket 10 is positioned at the upper end of the vertical groove portion 63a (that is, the start end of the upper horizontal groove portion 63c). Thereafter, the drive device is operated to rotate the kelly bar 40, and after the protruding portion 64 of the main body bucket 10 is positioned at the tip of the upper horizontal groove portion 63c, the operation of the drive device is stopped. Thereby, the inner container 20 is located at the highest position. As the internal container 20 is raised, a space is formed in the lower part of the main body bucket 10.

  [4] After that, the driving device is operated again to rotate the drilling bucket 200 while being pressed against the bottom wall of the excavation hole A. Thereby, earth and sand are taken in in the space formed in the lower part of the main body bucket 10 by the raising of the internal container 20.

  [5] When the earth and sand in the main body bucket 10 reaches the maximum intake amount of the main body bucket 10 once, the operation of the driving device is stopped and the rotation of the drilling bucket 200 is stopped.

  [6] The heavy machinery is operated to lift the drilling bucket 200 to the ground. And the earth and sand taken in the inside of the inner container 20 and the main body bucket 10 are discharged | emitted outside the excavation hole A. FIG.

  For discharging the earth and sand, first, the bottom cover 12 of the main body bucket 10 is opened to drop the earth and sand. Next, the driving device is operated to reversely rotate the kelly bar 40 so that the protrusion 64 of the main body bucket 10 is positioned at the start end of the upper horizontal groove 63c (that is, the upper end of the vertical groove 63a), and then the drive Deactivate the equipment.

  Then, the lifting machine is operated to lower the kelly bar 40 so that the protruding portion 64 of the main body bucket 10 is positioned at the lower end of the horizontal groove portion 63a (that is, the start end of the lower horizontal groove portion 63b). Thereafter, the driving device is operated to rotate the kelly bar 40, and after the protruding portion 64 of the main body bucket 10 is positioned at the tip of the lower horizontal groove portion 63c, the operation of the driving device is stopped. Thereby, the inner container 20 is located at the lowest lowered position. Thereafter, the bottom lid 22 is opened and the earth and sand are dropped from the inner container 20.

  In addition, when discharging the earth and sand in the internal container 20, it is preferable to lower the internal container 20 after supporting the main body bucket 10 with a gantry installed on the ground.

  After all the earth and sand have been discharged, the bottom lid 22 of the inner container 20 is closed, and then the bottom lid 12 of the main body bucket 10 is closed. Since the positional relationship between the main body bucket 10 and the inner container 20 in the rotational direction is constant, the respective opening portions 13 and 23 and the guide plate 50 are positioned suitable for taking in earth and sand by closing the respective bottom lids 12 and 22. Become a relationship.

  The operations [1] to [6] are repeated until the excavation hole A reaches a desired depth.

  Thus, the maximum excavation amount of one drilling bucket 200 is the sum of the one maximum intake amount of the main body bucket 10 and the one maximum intake amount of the internal container 20.

  Both the main body bucket 10 and the inner container 20 have the same height as that of a normal drilling bucket in which soil and sand can be taken up and pushed up. Therefore, when the same drive unit as the normal drilling bucket is used, the body part 11 of the main body bucket 10 is about twice as long as the body part of the normal drilling bucket, and the body part 21 of the internal container 20 is used as the normal drilling bucket. If the inner container 20 is configured so that it can be raised to the central portion of the main body bucket 10 or more, the drilling bucket 200 will have the largest amount of excavation and the highest working efficiency. .

  As described above, in the state where the internal container 20 is positioned at the lowest lowered position, earth and sand can be taken into the internal container 20 through the opening 13, the guide plate 50, and the opening 23, and the internal container In the state where it is located at the highest position, earth and sand can be taken into the main body bucket 10 through the opening 13.

  Therefore, when the same drive device as the drive device that drives the conventional drilling bucket is used, both the inner container 20 and the main body bucket 10 can take up the soil to the same height as the conventional one. Therefore, even when the same drive unit as in the conventional case is used, it is possible to increase the maximum excavation amount per time as compared with the conventional case.

  As a result, the number of times the drilling bucket 200 is raised and lowered can be reduced, and the skin of the hole wall and the occurrence of slime can be reduced.

  Furthermore, it is the structure which only added the internal container 20 and the guide plate 50 comprised so that raising / lowering was possible in the main body bucket 10 with respect to the conventional drilling bucket. Therefore, a complicated power transmission mechanism as in the technique described in Patent Document 1 is not required.

  And it is possible to take the earth and sand into the internal container 20 and the main body bucket 10 to the same predetermined height determined by the driving force of the driving device or the like. Therefore, the length of the body portion 11 of the main body bucket 10 is preferably at least twice as long as the length of the body portion 21 of the internal container 20.

  The groove portion may be provided outside the inner container 20 and the protruding portion may be provided inside the main body bucket 10. Moreover, you may provide a protection member so that earth and sand may not enter into a groove part.

  DESCRIPTION OF SYMBOLS 10 ... Main body bucket, 11 ... Body part (bucket body part), 11a ... Groove part, 12 ... Bottom cover (bucket bottom cover), 13 ... Opening part (bucket opening part), 14 ... Cutting edge (cutting blade), 20 ... Inner container, 21 ... trunk (container trunk), 21a ... projection, 22 ... bottom lid (container bottom lid), 23 ... opening (container opening), 30 ... hydraulic cylinder, 40 ... kelly bar, 41 ... coupling Pins 50... Guide plate 63 63 Grooves 63a Vertical grooves 63b Lower horizontal grooves 63c Upper horizontal grooves 64 Projections 100, 200 Drilling buckets A Drilling holes

Claims (5)

A drilling bucket for taking excavated earth and sand into the bucket,
It consists of a main body bucket and an internal container built in the main body bucket and configured to be movable up and down in the main body bucket,
The main body bucket includes a cylindrical bucket body portion, a bucket bottom lid provided at the bottom of the bucket body portion so as to be freely opened and closed, and a bucket opening formed in the bucket bottom lid,
The inner container includes a cylindrical container body portion having a smaller diameter than the bucket body portion, a container bottom lid provided at the bottom of the container body portion so as to be openable and closable, and a container opening formed in the container bottom lid And
A guide plate for guiding the earth and sand taken from the bucket opening to the container opening when the bucket is rotated with the bucket bottom lid pressed against the bottom wall of the excavation hole in a state where the inner container is at the lowest position Is provided with a drilling bucket.   The drilling bucket according to claim 1, wherein the length of the bucket body is at least twice as long as the length of the container body.   3. The drilling according to claim 1, wherein the bucket body portion and the container body portion are connected via a hydraulic cylinder, and the internal container moves up and down in the main body bucket by expansion and contraction of the hydraulic cylinder. bucket.   A kerry bar is connected to an upper portion of the inner container, the inner container moves up and down in the main body bucket by power through the kelly bar, and power transmitted to the inner container through the kelly bar is transmitted to the main body bucket. The drilling bucket according to claim 1, further comprising a transmission mechanism that transmits and lifts and rotates the main body bucket. A drilling method of a drilling hole using a drilling bucket comprising a main body bucket and an internal container built in the main body bucket and configured to be movable up and down in the main body bucket,
Inserting the drilling bucket into the excavation hole in a state where the inner container is located at the lowest position;
The drilling bucket is rotated in a state where it is pressed against the bottom wall of the excavation hole, and the earth and sand taken from the bucket opening formed at the bottom of the main body bucket is transferred to the bottom of the internal container via a guide plate. Taking into the internal container from the formed container opening;
Stopping the rotation of the drilling bucket and moving the internal container that has taken in the soil upwards;
The drilling bucket is rotated in a state where it is pressed against the bottom wall of the excavation hole, and the sand is discharged from the bucket opening into the space formed inside the main body bucket by moving the internal container upward. Capture process;
A step of stopping the rotation of the drilling bucket and discharging the earth and sand taken into the main body bucket and the inner container to the outside of the excavation hole.

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