Chucking mechanism of pile extraction machine, and pile extraction method

Abstract

The challenge is to create a simple structure that can extract even heavy existing piles. [Solution] A chucking mechanism for a pile extraction machine that extracts existing piles, comprising: a cylindrical casing 3; an outer cylindrical portion 4 provided on the outer circumferential surface side concentric with the casing and movable along the casing; and a claw 1, one end of which is pivotally supported on the outer cylindrical portion and the other end of which can be erected toward the center of the cross-section of the casing through an erection window 14 provided in the casing, wherein the surface T1 of the erection window toward the casing tip can support the surface F of the erected claw toward the casing tip.

Description

[Technical Field]

[0001] The present invention relates to a chucking mechanism for a pile extractor and a pile extraction method used for extracting existing piles buried underground when reconstructing an architectural structure or the like. [Background Art]

[0002] In architectural structures such as buildings and condominiums, piles are embedded underground to support the load of the structures. When reconstructing these architectural structures, it is necessary to remove the existing embedded piles. Conventionally, to remove existing piles, the existing piles are crushed and taken out, or the existing piles are pulled out with a wire and then removed.

[0003] Patent Document 1 discloses that an upper claw having one end pivotally supported is provided on an outer cylindrical portion formed on a peripheral wall near the lower end of a casing, a lower claw having one end pivotally supported is provided on an outer peripheral wall portion of the casing below the outer cylindrical portion, the other end of the upper claw and the other end of the lower claw are pivotally connected, and the outer cylindrical portion is moved toward the tip end of the casing by a hydraulic cylinder, whereby the other end of the upper claw and the other end of the lower claw stand up toward the center side of the cross-section of the casing to support the lower end of the existing pile and pull out the existing pile. A configuration is described therein. [Prior Art Documents] [Patent Documents]

[0004] Patent Document 1: Japanese Patent No. 6465511 [Summary of the Invention] [Problems to be Solved by the Invention]

[0005] However, the device described in Patent Document 1 has a complicated structure because it must be provided with the upper claw and the lower claw, and there has been a problem that when pulling out a heavy existing pile, the pivotally supporting portions at one end and the other end of the lower claw cannot bear the weight of the existing pile and may be damaged.

[0006] The present invention aims to solve the above problems and enable the extraction of heavy existing piles with a simple structure. [Means for solving the problem]

[0007] To solve the above problems, the present invention provides a chucking mechanism for a pile extraction machine that extracts existing piles, It is possible to excavate the soil and dig into the ground. A cylindrical casing, An outer cylindrical portion is provided on the outer circumferential side concentric with the casing and is movable along the casing, One end of the outer cylindrical portion is pivotally supported, and the other end of the claw is able to stand upright on the side of the cross-sectional center of the casing through an uprighting window provided in the casing, A hydraulic cylinder provided in the casing, Equipped with, As the hydraulic cylinder extends, the outer cylindrical portion moves toward the tip of the casing, allowing the claw to be raised toward the center of the cross-section of the casing. The present invention provides a chucking mechanism for a pile extraction machine, characterized in that the surface of the upright window facing the casing tip can support the surface of the upright claw facing the casing tip.

[0008] This configuration allows the claws to support existing piles independently, and the upright windows in the casing can support the claws under heavy loads, making it possible to extract even heavy existing piles with a simple structure.

[0009] A chucking mechanism for a pile extraction machine, The hydraulic cylinder compresses, causing the outer cylindrical portion to move in the opposite direction to the casing tip. The aforementioned claw The tip points downwards The casing may be configured to be able to collapse toward the inner circumferential wall.

[0010] With this configuration, when the casing is buried in the ground... Kini In a direction that does not resist the pressure of the soil. By hydraulic cylinder The outer cylindrical section can be positioned, allowing for easy extraction of existing piles.

[0013] Furthermore, in order to solve the above problems, the present invention provides a pile extraction method for pulling out existing piles, A cylindrical casing with an outer cylindrical section on its outer surface is positioned around the existing pile. Excavate the soil and dig deeper into the ground.A casing embedding step, Extend the hydraulic cylinder moving said outer cylindrical portion toward the distal end of said casing; height, a claw erecting step of erecting, toward the cross-sectional center side of said casing through an erection window provided in said casing, a claw having one end pivotally supported on said outer cylindrical portion, and supporting the surface, on the distal end side of said casing, of the erected claw with the surface, on the distal end side of said casing, of said erection window; and a casing pulling step of pulling out said casing so that an existing pile is supported by said claws and pulled out, wherein a pile pulling method is provided.

[0014] With this configuration, the existing pile can be supported by the claws alone, and the claws bearing heavy loads can be supported by the erection window provided in the casing, so that even heavy existing piles can be pulled out with a simple structure.

[0015] A pile pulling method, wherein before said casing embedding step, said Compress the hydraulic cylinder moving said outer cylindrical portion in a direction opposite to the distal end direction of said casing; height, said claw The tip points downwards may be configured to execute a claw laying step of laying said claw down on the inner peripheral wall side of said casing.

[0016] With this configuration, the claws are laid down on the inner peripheral wall side of the casing, thereby reducing soil resistance and allowing the casing to be embedded into the ground. [Effects of the Invention]

[0017] According to the chucking mechanism of a pile puller and the pile pulling method of the present invention, even heavy existing piles can be pulled out with a simple structure. [Brief Description of the Drawings]

[0018] [Figure 1] It is a side view explaining the chucking mechanism of the pile puller in Example 1 of the present invention. [Figure 2] It is a bottom view explaining the chucking mechanism of the pile puller in Example 1 of the present invention. [Figure 3] It is a diagram illustrating the operation of the claws of the chucking mechanism of the pile extractor in Example 1 of the present invention. [Figure 4] It is a diagram illustrating the preparation step of the pile extraction method in Example 1 of the present invention. [Figure 5] It is a diagram illustrating the first half of the casing embedding step and the casing pulling step in Example 1 of the present invention. [Figure 6] It is a diagram illustrating the second half of the casing pulling step in Example 1 of the present invention. MODE FOR CARRYING OUT THE INVENTION EXAMPLES

[0019] Example 1 of the present invention will be described. FIG. 1 is a side view illustrating the chucking mechanism of the pile extractor in Example 1 of the present invention. FIG. 2 is a bottom view illustrating the chucking mechanism of the pile extractor in Example 1 of the present invention. FIG. 3 is a diagram illustrating the operation of the claws of the chucking mechanism of the pile extractor in Example 1 of the present invention. FIG. 4 is a diagram illustrating the preparation step of the pile extraction method in Example 1 of the present invention. FIG. 5 is a diagram illustrating the first half of the casing embedding step and the casing pulling step in Example 1 of the present invention. FIG. 6 is a diagram illustrating the second half of the casing pulling step in Example 1 of the present invention.

[0020] (Chucking Mechanism) Example 1 of the present invention, as shown in FIG. 4, is to extract an existing pile P buried in the ground by a telescopic crawler-type pile extractor 10 that is capable of caterpillar movement and easy to assemble. This telescopic crawler-type pile extractor 10 includes a cylindrical casing 3 formed by joining five cylindrical split casings. Each split casing is joined to another by bolts.

[0021] In addition, although the number of split casings is set to five in Example 1, it is not necessarily limited to this, and can be appropriately changed depending on circumstances such as the length of the existing pile. For example, the number may be four or less, or six or more.

[0022] Existing piles P buried underground have a diameter of approximately 150 mm to 650 mm and a length of 6 m to 22 m. Their materials include cement (PC piles), pine (pine piles), and steel pipes (steel pipe piles). The casing 3 is selected to match the diameter and length of the existing pile. Specifically, the inner diameter of the casing 3 is larger than the diameter of the existing pile P, and its length is longer than the length of the existing pile P.

[0023] In this invention, the direction D (-Z direction) shown in Figures 1 and 3 is defined as the tip direction D of the casing.

[0024] As shown in Figures 1-3, an outer cylindrical portion 4 is provided concentrically on the outer circumferential surface near the tip of the casing 3. The outer cylindrical portion 4 can be moved along the casing 3 by a hydraulic cylinder (not shown). Furthermore, a tip cylindrical portion 5 is fixed to the casing 3 at the very tip D of the casing 3, beyond the outer cylindrical portion 4. Claw support portions 6 are fixed to the outer circumferential wall of this tip cylindrical portion 5 at 120° intervals.

[0025] Let me explain in detail. The outer circumferential wall of the outer cylindrical portion 4 is provided with claw shaft support portions 12 (12a, 12b, 12c) at 120° intervals corresponding to the claw support portions 6 (6a, 6b, 6c), and one end of the claw 1 (1a, 1b, 1c) is pivotally supported by the claw shaft support portions 12 (12a, 12b, 12c) in a direction perpendicular to the tip direction D of the casing 3. The outer cylindrical portion 4 is connected to a hydraulic cylinder (not shown), and when this hydraulic cylinder extends, the outer cylindrical portion 4 can be moved along the casing 3 in the tip direction D of the casing, and when the hydraulic cylinder compresses, the outer cylindrical portion 4 can be moved in the opposite direction to the tip direction D of the casing. Then, by moving the outer cylindrical portion 4 toward the tip direction D of the casing 3, the claws 1 (1a, 1b, 1c) can be erected toward the center of the cross-section of the casing 3, and by moving the outer cylindrical portion 4 in the opposite direction to the tip direction D of the casing 3, the claws 1 (1a, 1b, 1c) can be folded toward the inner circumferential wall of the casing 3.

[0026] At the lower end of the casing 3, the claws 1 (1a, 1b, 1c) are positioned upright, and upright windows 14 (14a, 14b, 14c) are cut out for each claw 1 (1a, 1b, 1c) to allow them to fall over. The lower end T1 (the end in the direction D towards the casing tip) is capable of supporting the face F of the claws 1 (1a, 1b, 1c) on the D side towards the casing tip when the claws 1 (1a, 1b, 1c) are upright. This allows the lower end T1 to support the face F of the upright claws 1 (1a, 1b, 1c) on the D side towards the casing tip, enabling the claws 1 (1a, 1b, 1c) to firmly support heavy existing piles P.

[0027] Multiple drilling blades 11 are provided at the lowest end of the casing 3, allowing the casing 3 to be embedded in the ground by using these drilling blades 11 to excavate the soil and dig deeper into the ground.

[0028] The claws 1 (1a, 1b, 1c) are made primarily of iron, capable of withstanding the weight of the existing pile P to be pulled out, and have dimensions to contact the existing pile P. In Example 1, the claws are approximately 200-300 mm long, 100 mm wide, and 50 mm thick.

[0029] In Example 1, the claws 1 (1a, 1b, 1c) were configured to tilt toward the inner circumferential wall, but more preferably they are configured to tilt outward from the inner circumferential wall. This reduces the effect of soil pressure during the casing embedding process described later.

[0030] In Example 1, the number of claws was set to three, but this is not necessarily limited to this, and can be changed as appropriate depending on the weight of the existing pile to be pulled out. For example, the number of claws may be four or more, or it may be two. Also, in Example 1, the number of hydraulic cylinders can be changed as appropriate depending on the weight of the existing pile. For example, there may be three or more hydraulic cylinders.

[0031] Furthermore, in Example 1, the tips of the claws 1 (1a, 1b, 1c) are formed in a rounded shape, but this is not necessarily limited to this and can be modified as appropriate. For example, the tips may be formed at an acute angle to enable the holding or crushing of existing piles P.

[0032] (Pile extraction method) First, a preparation step is performed to prepare a cylindrical casing 3 with an outer cylindrical section 4 concentrically located near the tip. In this preparation step, a casing 3 is prepared by joining together multiple segmented casings, and the lowest segmented casing has multiple drilling blades 11. More specifically, as shown in Figure 4, a telescopic crawler type pile extractor 10 that can move on caterpillar tracks and is easy to assemble is prepared. This telescopic crawler type pile extractor 10 has a casing 3 made by joining together five segmented casings. Each segmented casing is joined together with bolts, and near the lower end of the lowest segmented casing has an outer cylindrical section 4 that pivotally supports three claws 1 (1a, 1b, 1c), and also has a tip cylindrical section 5 fixed to the tip side of the casing 3 from the outer cylindrical section 4, and a claw support section 6 fixed to this tip cylindrical section 5. The casing 3 has a cutout for uprighting, and the surface T1 of this uprighting window 14, which is in the opposite direction to the casing tip direction D, can support the surface F of the upright claws 1 (1a, 1b, 1c) in the casing tip direction D.

[0033] In Example 1, a telescopic crawler-type pile extractor was used, but this is not necessarily limited to this configuration and can be modified as appropriate. For example, a rough terrain crane-type pile extractor may be used. Also, the pile extractor does not necessarily have to be a caterpillar-type machine. Furthermore, although the number of segmented casings was set to five, this is not necessarily limited to this and can be changed as appropriate depending on the length of the existing pile, etc. For example, it may be four or fewer, or six or more.

[0034] Existing piles P are buried underground. These existing piles P have a diameter of approximately 150 mmφ to 650 mmφ and a length of 6 m to 22 m, and are made of materials such as cement (PC piles), pine (pine piles), or steel pipes (steel pipe piles). In this invention, as shown in Figure 4, the underground end of the existing pile P is defined as tip P1, and the end closer to the surface is defined as end P2.

[0035] Casing 3 is selected to match the diameter and length of the existing pile. That is, the inner diameter of casing 3 is larger than the diameter of the existing pile P, and the length is longer than the length of the existing pile P. The soil is excavated in advance so that the end P2 of the existing pile P closest to the ground surface is visible.

[0036] Next, a hydraulic cylinder (not shown) is compressed to move the outer cylindrical portion 4 in the opposite direction to the tip direction D of the casing 3, and a claw-folding process is performed to cause the claws 1 (1a, 1b, 1c) pivotally supported on the outer peripheral wall of the outer cylindrical portion 4 to bend toward the inner peripheral wall of the casing 3.

[0037] Next, a casing embedding process is performed in which the casing 3 is embedded in the ground deeper than the existing pile P so that it is positioned around the existing pile P. To explain in more detail, first, as shown in Figure 5(a), the casing 3 is positioned around the existing pile P, and then the soil is dug with multiple excavation blades 11 while the casing 3 is rotated in the forward direction, and the claws 1 (1a, 1b, 1c) are embedded deeper than the tip P1 of the existing pile P. At this time, the claws 1 (1a, 1b, 1c) are bent toward the inner circumferential wall side of the casing 3, so there is less resistance from the soil and it can be embedded smoothly.

[0038] Next, the claw erection process is performed to extend a hydraulic cylinder (not shown) and move the outer cylindrical portion 4 toward the tip of the casing 3, thereby erecting the claws 1 (1a, 1b, 1c), one end of which is pivotally supported by the outer cylindrical portion 4, toward the center of the cross-section of the casing 3 through the erection windows 14 (14a, 14b, 14c), and supporting the lower end surface F of the claws 1 (1a, 1b, 1c) on the lower end T1 of the erection windows 14 (14a, 14b, 14c). This allows the claws 1 (1a, 1b, 1c) to support the heavy existing pile P.

[0039] Then, the casing extraction process is performed to extract the existing pile P together with the casing 3 (see Figures 5(b) and 5(c)). In other words, when the casing 3 is extracted while the claws 1 (1a, 1b, 1c) are standing upright towards the center of the cross-section of the casing 3, the upright claws 1 (1a, 1b, 1c) support the existing pile P, and the lower end surfaces F of the claws 1 (1a, 1b, 1c) come into contact with the lower end T1 of the upright windows 14 (14a, 14b, 14c), withstanding the weight of the existing pile P and allowing the existing pile P to be extracted.

[0040] In this way, the claws 1 (1a, 1b, 1c) support the tip P1 of the existing pile P and pull out the casing 3, so that even if the existing pile P is broken in the middle, the entire existing pile P can be pulled out together with the casing 3.

[0041] Finally, the claw lowering process is performed again to lower the claws 1 (1a, 1b, 1c) toward the inner circumferential wall of the casing 3, releasing the support for the tip P1 of the existing pile P, thereby causing the existing pile P to fall and land. Specifically, as shown in Figure 6(a), at the location where the existing pile P is to be lowered, the hydraulic cylinder is compressed to lower the claws 1 (1a, 1b, 1c), and the casing 3 is pulled up, thereby lowering the existing pile P to the ground and completing the extraction of the existing pile P (see Figure 6(b)).

[0042] In Example 1, the claw-folding process was performed first, but this is not necessarily the only option and can be modified as appropriate. If the claws 1 (1a, 1b, 1c) have already folded towards the inner circumferential wall of the casing 3, the claw-folding process does not need to be performed.

[0043] Furthermore, in Embodiment 1, a hydraulic cylinder was used for the raising and lowering of the claws 1 (1a, 1b, 1c), but this is not necessarily limited and can be changed as appropriate depending on the circumstances. For example, a mechanism may be provided that lowers and raises the claws 1 (1a, 1b, 1c) by forward and reverse rotation of the casing 3 without relying on a hydraulic cylinder. In that case, when raising the claws 1 (1a, 1b, 1c) to the center side of the cross-section of the casing 3, the casing 3 should be reversed, and when lowering the claws 1 (1a, 1b, 1c) toward the inner circumferential wall side of the casing 3, the casing 3 should be rotated forward. At a minimum, when raising, the claws 1 (1a, 1b, 1c) should be raised in a direction perpendicular to the tip direction D of the casing 3. This makes it possible to withstand the weight of even heavy existing piles P and pull them out.

[0044] Furthermore, in Example 1, the casing 3 was embedded in the casing embedding process so that the claws 1 (1a, 1b, 1c) were deeper than the tip P1 of the existing pile P. However, this is not necessarily limited to this and can be modified as appropriate. For example, the claw erection process may be performed at a point shallower than the tip P1 of the existing pile P to support the middle of the existing pile P (between the tip P1 and the end P2) and then the casing extraction process may be performed. In this case, it is preferable to form the tips of the claws 1 (1a, 1b, 1c) at an acute angle.

[0045] Thus, in Embodiment 1 of the present invention, the chucking mechanism of a pile extraction machine for extracting existing piles is as follows: A cylindrical casing, An outer cylindrical portion is provided on the outer circumferential side concentric with the casing and is movable along the casing, One end of the outer cylindrical portion is pivotally supported, and the other end of the claw is able to stand upright on the side of the cross-sectional center of the casing through an uprighting window provided in the casing, Equipped with, The chucking mechanism of the pile extraction machine is characterized in that the surface of the upright window facing the casing tip can support the surface of the upright claw facing the casing tip, allowing the claw to support the existing pile by itself, and the upright window provided in the casing can support the claw with a heavy load, thus enabling the extraction of even heavy existing piles with a simple structure.

[0046] Furthermore, in Embodiment 1 of the present invention, the pile extraction method involves pulling out existing piles, The casing embedding process involves embedding a cylindrical casing, which has an outer cylindrical section on its outer surface, into the ground so that it is positioned around the existing pile. A claw erection step is performed by moving the outer cylindrical portion toward the tip of the casing, thereby erecting the claw, one end of which is pivotally supported by the outer cylindrical portion, toward the center of the cross-section of the casing through an erection window provided in the casing, and supporting the surface of the erected claw toward the tip of the casing with the surface of the erection window toward the tip of the casing, This pile extraction method is characterized by performing a casing extraction step, in which the casing is pulled out so that the claws support and pull out the existing pile. As a result, the claws can support the existing pile by themselves, and the upright windows provided in the casing can support the claws with heavy loads, making it possible to extract even heavy existing piles with a simple structure. [Industrial applicability]

[0047] The chucking mechanism for the pile extraction machine and the pile extraction method in the present invention can be widely used in the field of extracting existing piles. [Explanation of Symbols]

[0048] 1(1a, 1b, 1c): Nail 3: Casing 4: Outer cylindrical part 5: Cylindrical tip 6 (6a, 6b, 6c): Claw support part 10: Pile extractor 11: Drill bit 12(12a, 12b, 12c): Claw shaft support 14 (14a, 14b, 14c): Standing window 20: Chucking mechanism D: Direction of the casing tip P: Existing pile P1: Tip P2: End

Claims

1. A chucking mechanism for a pile extraction machine that extracts existing piles, A cylindrical casing that can excavate soil and dig into the ground, An outer cylindrical portion is provided on the outer circumferential side concentric with the casing and is movable along the casing, One end of the outer cylindrical portion is pivotally supported, and the other end of the claw is able to stand upright on the side of the cross-sectional center of the casing through an uprighting window provided in the casing, The casing includes a hydraulic cylinder, As the hydraulic cylinder extends, the outer cylindrical portion moves toward the tip of the casing, allowing the claw to be raised toward the center of the cross-section of the casing. A chucking mechanism for a pile extraction machine, characterized in that the surface of the upright window facing the casing tip can support the surface of the upright claw facing the casing tip.

2. The chucking mechanism for a pile extractor according to Claim 1, characterized in that the hydraulic cylinder compresses the outer cylindrical portion, causing it to move in the opposite direction to the casing tip, so that the tip of the claw can be tilted downward toward the inner circumferential wall of the casing.

3. This is a pile extraction method that involves pulling out existing piles. The casing embedding process involves excavating the soil around the existing pile and drilling downwards into the ground to embed a cylindrical casing, which has an outer cylindrical section on its outer surface, and A claw erection step is performed by extending the hydraulic cylinder to move the outer cylindrical portion toward the tip of the casing, erecting the claw, one end of which is pivotally supported on the outer cylindrical portion, toward the center of the cross-section of the casing through an erection window provided in the casing, and supporting the surface of the erected claw toward the tip of the casing with the surface of the erection window toward the tip of the casing, A pile extraction method characterized by performing a casing extraction step, in which the claws support and extract the existing pile by pulling out the casing.

4. The pile extraction method according to claim 3, characterized in that, prior to the casing embedding step, a claw tilting step is performed in which the hydraulic cylinder is compressed to move the outer cylindrical portion in the opposite direction to the tip of the casing, so that the tip of the claw points downward and tilts toward the inner circumferential wall of the casing.

Images