Hangzhou Games

Abstract

To provide a pile driver comprising a vibration preventing member capable of coping with a plurality of pipe diameters by a simple arrangement change.SOLUTION: A vibration preventing member 22 comprises a pair of rotation arms 32, 33 having large diameter arcuate recessed portions 34, 35 capable of being in contact with an outer peripheral surface of a large diameter steel pipe pile. The pair of rotation arms are provided with a plurality of collars 39, 40, 41, 42 which face with each other in a closed state and which can be replaced according to outer diameters of small diameter steel pipe piles 71 to 76. The collar includes: a small diameter arcuate recessed portion 47 provided inside the large diameter arcuate recessed portion in a concentric manner; a support arm 48 penetrating the large diameter arcuate recessed portion in a radial direction and supporting the small diameter arcuate recessed portion so as to be movable forward / backward with respect to an arcuate center C of the large diameter arcuate recessed portion; and fixing means 49 comprising key engagement fixing the small diameter arcuate recessed portion at a moving position.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a pile driver, and more particularly to a pile driver equipped with an anti-vibration member that supports a steel pipe pile attached to a working device so that the pile can rotate and move axially. [Background technology]

[0002] Pile drivers that install steel pipe piles are equipped with anti-vibration members that prevent the steel pipe piles from tilting or becoming misaligned during installation. These anti-vibration members include a pair of left and right rotating arms that are attached to the lower part of the leader in an openable and closable manner. The tips of both rotating arms are provided with connecting parts that connect the two tips together, and by rotating the arms to connect the connecting parts and holding the steel pipe pile in the arc-shaped recesses provided in the arms, the steel pipe pile attached to the work device can be supported so that it can rotate and move axially (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-218538 Summary of the Invention [Problem to be solved by the invention]

[0004] The anti-vibration members mentioned above are available in a variety of collars with different dimensions to accommodate piles with different diameters. However, as the number of collar types increases, it becomes more time-consuming to rearrange them, and there are also management issues, such as where to store unused collars.

[0005] Therefore, an object of the present invention is to provide a pile driver equipped with an anti-vibration member that can accommodate a plurality of pile diameters with a simple setup change. [Means for solving the problem]

[0006] In order to achieve the above object, the pile driver of the present invention is a pile driver in which a working device is provided so as to be able to rise and fall along a leader erected at the front of a base machine, and an anti-vibration member is provided at the bottom of the leader to embrace the outer circumferential surface of a steel pipe pile that is rotationally driven by the working device, and the anti-vibration member has a pair of rotating arms having a large-diameter arc-shaped recess that can abut against the outer circumferential surface of the steel pipe pile, and the rotating ends of the pair of rotating arms approach each other and close together around a pair of rotating shafts provided at the bottom of the leader. and an open state in which the steel pipe pile is spaced apart, and the pair of rotating arms are provided with a plurality of collars that are arranged opposite each other in the closed state and that can be rearranged according to the outer diameter of the steel pipe pile, and the collars have a small-diameter arc-shaped recess that is concentrically provided inside the large-diameter arc-shaped recess, a support arm that penetrates the large-diameter arc-shaped recess in the radial direction and supports the small-diameter arc-shaped recess so that it can advance and retreat with respect to the arc center of the large-diameter arc-shaped recess, and a fixing means that fixes the small-diameter arc-shaped recess at a moving position. The support arm is rod-shaped with a rectangular cross section, and a plurality of key grooves are formed on the upper surface thereof. The large-diameter arc-shaped recess has an arm through-hole that matches the cross-sectional width of the support arm. The fixing means is a key engagement that is fixed by fitting a key plate into the key groove. It is characterized by the following.

[0007] Furthermore, the pair of pivot arms are characterized in that, in the closed state, an opening is provided between the large-diameter arc-shaped recesses on the pivot base side, and the position of the small-diameter arc-shaped recess relative to the support arm is eccentric to one circumferential side toward the pivot end. [Effects of the Invention]

[0009] According to the pile driver of the present invention, the multiple collars of the anti-vibration member have small-diameter arc-shaped recesses that can move forward and backward relative to the center of the large-diameter arc-shaped recess, making it possible to provide an adjustment range that can accommodate multiple pile diameters with the same type of collar. This reduces the number of types of collars compared to the conventional method of providing collars for each pile diameter, and minimizes the storage space for unused collars. Furthermore, since the collars can be held in their new position simply by operating the fixing means, it also contributes to reducing the labor and time required for setup changes.

[0010] Furthermore, because the small-diameter arc-shaped recesses are eccentric to one side in the circumferential direction toward the rotation end with respect to the support arms that radially penetrate the large-diameter arc-shaped recesses, it is possible to create openings between the small-diameter arc-shaped recesses that are the same type as the openings created between the large-diameter arc-shaped recesses, eliminating unnecessary interference between the collars and the steel pipe pile when opening and closing the anti-vibration member.In particular, even in the closed state with openings created between the collars, the arrangement space for the support arms is not obstructed, and a well-balanced support state can be achieved with four support arms arranged at equal intervals in the circumferential direction.

[0011] Furthermore, the large-diameter arc-shaped recess has an arm through-hole that matches the cross-sectional width of the support arm, and the small-diameter arc-shaped recess uses a key engagement as a fastening mechanism. Therefore, the rotational force of the impact applied to the support arm by the rotating steel pipe pile is absorbed by the wall of the arm through-hole, and the direction of force transmission from the steel pipe pile is limited to the axial direction of the arm. This allows for stable key engagement through simple surface contact, despite the unique behavior of rotating piles, which are prone to fluctuations in force direction and magnitude. In particular, the structure uses multiple key grooves into which the key plates selectively fit, allowing for a wide range of pile diameters to be easily accommodated. In other words, this anti-vibration member achieves both maintaining the collar connection and improving reassembly workability. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a side view of a pile driver showing an example of an embodiment of the present invention. [Figure 2] FIG. [Figure 3] FIG. [Figure 4] FIG. [Figure 5] FIG. 10 is a plan view showing the assembled state of the collar corresponding to the first steel pipe pile. [Figure 6] 6 is a cross-sectional view taken along the line VI-VI in FIG. 5. [Figure 7] FIG. 7 is a cross-sectional view taken along line VII-VII in FIG. 6. [Figure 8]FIG. 8 is a cross-sectional view taken along line VIII-VIII in FIG. 6. [Figure 9] FIG. [Figure 10] FIG. 10 is a plan view showing the assembled state of the collar corresponding to the second steel pipe pile. [Figure 11] 11 is a cross-sectional view taken along the line XI-XI in FIG. [Figure 12] FIG. 10 is a plan view showing the assembled state of the collar corresponding to the third steel pipe pile. [Figure 13] 13 is a cross-sectional view taken along the line XIII-XIII in FIG. 12. [Figure 14] FIG. 10 is a plan view showing the assembled state of the collar corresponding to the fourth steel pipe pile. [Figure 15] 15 is a cross-sectional view taken along the line XV-XV in FIG. 14. [Figure 16] FIG. 10 is a plan view showing the assembled state of the collar corresponding to the fifth steel pipe pile. [Figure 17] 17 is a cross-sectional view taken along the line XVII-XVII in FIG. 16. [Figure 18] FIG. 10 is a plan view showing the assembled state of the collar corresponding to the sixth steel pipe pile. [Figure 19] 19 is a cross-sectional view taken along the line XIX-XIX in FIG. 10. DETAILED DESCRIPTION OF THE INVENTION

[0013] Figures 1 to 19 show one embodiment of a pile driver of the present invention. As shown in Figure 1, the pile driver 11 is a dual-purpose machine that can switch between steel pipe pile construction and ground improvement construction, and is equipped with a base machine 14 consisting of a lower track body 12 equipped with crawlers and an upper rotating body 13 rotatably mounted on the lower track body 12, a leader 15 mounted to the front of the upper rotating body 13 so that it can be raised and lowered, and a hoisting cylinder 16 that supports the leader 15 from the rear. A leader support 17 that supports the leader 15 so that it can be raised and lowered is provided at the front of the upper rotating body 13, and a driver's cab 18 is provided on the right side of the upper rotating body 13, and an equipment room 19 that houses an engine and hydraulic unit is provided on the left side.

[0014] The leader 15 is made up of multiple leader members connected together, each with a rectangular cylindrical cross section, and is rotatably attached to a support shaft in the vehicle width direction provided on the leader support 17. A top sheave 20 around which a lifting rope is wound is disposed at the upper end of the leader 15, and an anti-vibration member 22 that prevents the steel pipe pile 21, which is driven to rotate, from vibrating is disposed at the front lower part. A pair of left and right guide pipes 23, 23 are continuously provided at the front end of both sides of the leader 15 over the entire length of the leader 15.

[0015] An auger 24, which is a working device, is attached to the front of the leader 15. The auger 24 can connect steel pipe piles 21 of a plurality of sizes (different diameters) via an adapter 25, and a pair of left and right guide gibs 24a, 24a that slide against the guide pipes 23, 23 are provided protruding rearward. The auger 24 can be raised and lowered along the front of the leader 15 by a lifting chain 28 that is stretched across a driving sprocket 26 and a driven sprocket 27 that are provided above and below the leader 15.

[0016] 2 to 4, the anti-vibration member 22 is attached via a bracket 29 provided at the lower end of the leader 15, and a first rotating shaft 30 and a second rotating shaft 31 are provided on both sides of the bracket 29 in the vertical direction, and a first rotating arm 32 is rotatably attached to the first rotating shaft 30, and a second rotating arm 33 is rotatably attached to the second rotating shaft 31. The first rotating shaft 30 and the second rotating shaft 31 are located in front of both sides in the width direction of the leader 15, and the distance between the two rotating shafts 30, 31 is larger than the outer diameter of the steel pipe pile 21.

[0017] Each of the pivoting arms 32, 33 has a substantially bilaterally symmetrical shape, and is flat with two arm-shaped plates arranged at a fixed interval facing each other above and below. The pivoting arms 32, 33 are equipped with a first pivoting base 32a and a second pivoting base 33a that are rotatably connected to the first pivoting shaft 30 and the second pivoting shaft 31, respectively, a first pile-holding portion 32b and a second pile-holding portion 33b that are formed at the tip side of the pivoting bases 32a, 33a and have a first large-diameter arc-shaped recess 34 and a second large-diameter arc-shaped recess 35 on the inside that embrace the outer peripheral surface of the steel pipe pile 21, and a first connecting portion 32c and a second connecting portion 33c that are provided at the tip ends of the pile-holding portions 32b, 33b, i.e., at the pivot ends of each pivoting arm 32, 33, that overlap each other and through which a connecting pin 36 is inserted.

[0018] Each of the pivot arms 32, 33 can be rotated about the first pivot shaft 30 and the second pivot shaft 31 between a closed state in which the pivot ends are close to each other and pin-coupled, as shown by the solid lines in Fig. 3, and an open state in which the pin coupling is released and the pivot ends are separated, as shown by the imaginary lines in Fig. 3. During the opening operation, an attached fixing pin 37 is inserted or removed, so that the fixing pin 37 engages with the overlapping portion with the bracket 29, thereby maintaining each of the pivot arms 32, 33 in the open state.

[0019] In this open state, the first large-diameter arc-shaped recess 34 and the second large-diameter arc-shaped recess 35 are separated from each other by the greatest distance on both sides of the bracket 29, so that they do not come into contact with the outer circumferential surface of the buried steel pipe pile 21 even when the upper rotating body 13 is rotated in place. On the other hand, in the closed state, the rotation end sides 34a, 35a of the large-diameter arc-shaped recesses 34, 35 are abutted against each other, while the rotation base sides 34b, 35b are spaced apart, with a large-diameter opening 38 provided therebetween. As a result, the rotation base sides of the large-diameter arc-shaped recesses 34, 35 do not come into contact with the steel pipe pile 21 when the anti-vibration member 22 is opened or closed.

[0020] When using the pile driver 11 configured in this manner to install, for example, a large-diameter steel pipe pile 21 (outer diameter 355.6 mm), after connecting the upper end of the steel pipe pile 21 to the adapter 25, as shown in FIG. 3, the anti-vibration member 22 is closed, and the rotating ends of both pivoting arms 32, 33 are pin-connected to each other so that the lower part of the steel pipe pile 21 is embraced by both large-diameter arc-shaped recesses 34, 35. In this closed state, the steel pipe pile 21 is buried in the ground by rotating and lowering the auger 24. At this time, the outer circumferential surface of the steel pipe pile 21 abuts against the inner arc-shaped circumferential surfaces 34c, 35c of the large-diameter arc-shaped recesses 34, 35, thereby suppressing vibration due to rotation.

[0021] When extending the steel pipe pile 21, the upper end of the buried steel pipe pile 21 is separated from the adapter 25, and the anti-vibration member 22 is opened in the reverse order of the above, while the upper rotating body 13 is rotated in place. Here, the prepared steel pipe pile 21 to be extended is connected at its upper end to the adapter 25 at a position to the side of the base machine 14 (lifting work position), and is carried to the construction position (pile core) by a rotation operation in the opposite direction.

[0022] When installing a variety of steel pipe piles with different outer diameters at the same site, it would be wasteful to prepare different sized collars to match the pile diameter, and it would also be a hassle to attach and detach collars every time the pile diameter changes. Therefore, the anti-vibration member 22 is equipped with an adjustment member that can accommodate multiple pile diameters with a simple setup change. This adjustment member consists of four retractable collars that can be rearranged according to the outer diameter of the steel pipe pile.

[0023] The retractable collars, which will be described in detail later, are compatible with six types of small-diameter steel pipe piles 71 to 76, each with a different outer diameter. In descending order of outer diameter, a set of four collars 39, 40, 41, and 42 is used for the first steel pipe pile 71 (outer diameter 318.5 mm), the second steel pipe pile 72 (outer diameter 267.4 mm), and the third steel pipe pile 73 (outer diameter 216.3 mm). A set of four collars 43, 44, 45, and 46 is used for the fourth steel pipe pile 74 (outer diameter 190.7 mm), the fifth steel pipe pile 75 (outer diameter 165.2 mm), and the sixth steel pipe pile 76 (outer diameter 139.8 mm). In other words, the retractable collars can be interchanged with each other or by rearranging the installation positions within the same set to accommodate six different pile diameters.

[0024] 5 to 13 show the assembled state of a first set of retractable collars corresponding to the first steel pipe pile 71, second steel pipe pile 72, and third steel pipe pile 73, which have relatively large outer diameters among the small-diameter steel pipe piles 71 to 76. As shown in Fig. 5, the four collars 39, 40, 41, 42 are arranged opposite each other at equal intervals (every 90 degrees) in the circumferential direction when the anti-vibration member 22 is closed, and basically all four are made of the same material, and when assembled to each rotating arm 32, 33, they are symmetrical in the left-right direction (up-down direction in Fig. 5).

[0025] Each collar 39, 40, 41, 42 has a small diameter arc-shaped recess 47 that is concentrically arranged inside the large diameter arc-shaped recess 34, 35, a support arm 48 that radially penetrates the large diameter arc-shaped recess 34, 35 and supports the small diameter arc-shaped recess 47 so that it can move back and forth relative to the arc center C of the large diameter arc-shaped recess 34, 35, i.e., the axis of the steel pipe pile 71, 72, 73, and a fixing means 49 that fixes the small diameter arc-shaped recess 47 to a moving position.

[0026] The small-diameter arc-shaped recess 47 is made of a steel plate having a size (thickness and circumferential length) that does not impair the adjustment allowance, and as shown in FIG. 9 and other figures, has an inner arc-shaped circumferential surface 47a that can abut against the outer circumferential surfaces of the steel pipe piles 71-73 and an outer arc-shaped circumferential surface (not shown) that is fixed to the tip of the support arm 48, and both circumferential ends of the inner arc-shaped circumferential surface 47a are chamfered. Furthermore, the position of the small-diameter arc-shaped recess 47 relative to the support arm 48 is eccentric to one circumferential side toward the pivot end, as shown in FIG. 5. As a result, on the pivot base side, between the plate ends 47b of the small-diameter arc-shaped recesses 47, 47, a small-diameter opening 50 corresponding to the first steel pipe pile 71, which is the same type as the large-diameter opening 38 corresponding to the large-diameter steel pipe pile 21, is provided, for example, in a state where a collar corresponding to the first steel pipe pile 71 is assembled.

[0027] The support arm 48 is shaped like a solid rod with a rectangular cross section, and has a key groove 48a formed on its upper surface. The key groove 48a is arranged in three stages in the arm axial direction, specifically, three key grooves 48a: a front stage, a middle stage, and a rear stage, in that order from the side closest to the small-diameter arc-shaped recess 47 (the left side in FIG. 6). When the support arm 48 is inserted into the arm through-holes 34d, 35d that pass through the large-diameter arc-shaped recesses 34, 35, the support arm 48 is positioned inside the pivot arms 32, 33, that is, as shown in the cross section of FIG. 6, in the space S between the upper and lower arm plates, extending to the full extent in the vertical direction.

[0028] 7, the arm through-holes 34d, 35d are aligned with the cross-sectional width (horizontal width) of the support arm 48, and relief grooves R are formed at the four corners. As a result, when the support arm 48 advances or retreats through the small-diameter arc-shaped recess 47, the support arm 48 can move linearly within the space S while sliding on its lower surface (sliding surface) 48c, with its side surface 48b slidably arranged on the side wall of the arm through-holes 34d, 35d.

[0029] As shown in Figures 6 and 8, the fixing means 49 is a key engagement that is fixed by fitting a key plate 49a into a key groove 48a of the support arm 48 from above. The key plate 49a has a plate width corresponding to the cross-sectional width of the support arm 48 and a plate thickness corresponding to the groove width of the key groove 48a, and as shown in Figure 9, etc., it can be engaged with the key groove 48a of each stage by selecting one of two key insertion holes 32d, 33d provided side by side in the arm-shaped upper plates of the rotating arms 32, 33. The key insertion holes 32d, 33d consist of two, front and rear, in order from the side closest to the large-diameter arc-shaped recesses 34, 35 (the left side in Figure 6).

[0030] With the key plate 49a fitted into the key groove 48a, the flange-shaped mounting plate 49b abuts against the arm-shaped upper plate, determining its position in the vertical direction, and the required overlap (lapping amount) in the arm axial direction is obtained between the collars 39, 40, 41, 42 and the key groove 48a. Thus, when the collars 39, 40, 41, 42 are keyed, they are fixed in the set positions of the pivot arms 32, 33 by tightening two mounting bolts 51 for the mounting plate 49b and one pressing bolt 52, the tip of which contacts the upper surface of the support arm 48.

[0031] When installing the first steel pipe pile 71 (outer diameter 318.5 mm), the first set of retractable collars 39, 40, 41, 42 thus formed is attached to the anti-vibration member 22 by key engagement between the front key groove 48a and the rear key insertion holes 32d, 33d, as shown in Figures 5 and 6. As a result, in the closed state, the inner arc-shaped circumferential surface 47a of the small-diameter arc-shaped recess 47 and the outer circumferential surface of the steel pipe pile 71 are positioned at a substantially uniform radial distance, and a small-diameter opening 50 is formed in a predetermined shape on the pivot base side. Thus, the outer circumferential surface of the first steel pipe pile 71 abuts substantially the entire inner arc-shaped circumferential surface 47a of the small-diameter arc-shaped recess 47, thereby suppressing vibration due to rotation. Meanwhile, when extending the steel pipe pile 71, the small-diameter opening 50 ensures a smooth movement path for opening and closing the anti-vibration member 22. Furthermore, by providing a plurality of key insertion holes 32d, 33d, the key grooves 48a can be spaced apart sufficiently, so that the strength of the support arm 48 does not become a problem.

[0032] When installing the second steel pipe pile 72 (outer diameter 267.4 mm), as shown in Figures 10 and 11, the middle key groove 48a is reassembled into key engagement with the rear key insertion holes 32d and 33d. As a result, in the closed state, the inner arc-shaped circumferential surface 47a of the small-diameter arc-shaped recess 47 and the outer circumferential surface of the steel pipe pile 72 are arranged with a gap G that is slightly wider on one circumferential side toward the rotation end due to the difference in curvature between them, which is smaller in diameter than the first steel pipe pile 71. However, even if such an uneven gap occurs, a necessary and sufficient contact area for holding the steel pipe pile 72 is ensured. A small-diameter opening 53 is provided in a predetermined shape on the rotation base side. Thus, the outer circumferential surface of the second steel pipe pile 72 abuts against most of the inner arc-shaped circumferential surface 47a of the small-diameter arc-shaped recess 47, thereby suppressing swing due to rotation. On the other hand, when the steel pipe pile 72 is extended, the small diameter opening 53 ensures a clear path for opening and closing the pile.

[0033] When installing the third steel pipe pile 73 (outer diameter 216.3 mm), the rear key groove 48a is reassembled to key engagement with the rear key insertion holes 32d, 33d, as shown in Figures 12 and 13. In this case, the gap G between the inner arc-shaped circumferential surface 47a of the small-diameter arc-shaped recess 47 and the outer circumferential surface of the steel pipe pile 73 is larger because the diameter of the small-diameter arc-shaped recess 47 is smaller than that of the second steel pipe pile 72, but a necessary and sufficient contact area is still ensured. A small-diameter opening 54 is provided in a predetermined shape on the rotation base side. In this way, the outer circumferential surface of the third steel pipe pile 73 abuts most of the inner arc-shaped circumferential surface 47a of the small-diameter arc-shaped recess 47, thereby suppressing vibration due to rotation. On the other hand, when extending the steel pipe pile 73, the small-diameter opening 54 ensures a sufficient flow path for opening and closing the pile.

[0034] As described above, the first set of retractable collars 39, 40, 41, 42 has an adjustment range that can accommodate the three types of steel pipe piles 71, 72, 73 with relatively large outer diameters among the six types of small-diameter steel pipe piles 71 to 76. Therefore, the adjustment range is exceeded for the three types of steel pipe piles 74, 75, 76 with smaller outer diameters, and they cannot be used as is. Therefore, the anti-vibration member 22 is provided with a second set of retractable collars 43, 44, 45, 46.

[0035] 14 to 19 show the assembled state of a second set of retractable collars corresponding to the fourth steel pipe pile 74, the fifth steel pipe pile 75, and the sixth steel pipe pile 76, which have relatively small outer diameters. The four collars 43, 44, 45, and 46 have the same shape as the first set of retractable collars but are different in length. The main difference is that they have a small-diameter arc-shaped recess 55 that is shorter in the circumferential direction and a support arm 56 that is longer in the axial direction. Furthermore, the assembly method (key engagement, etc.) is the same as that of the first set of retractable collars, and although a detailed description will be omitted, the small-diameter arc-shaped recess 55 is provided concentrically inside the large-diameter arc-shaped recess 34, 35, and the support arm 56 supports the small-diameter arc-shaped recess 55 so that it can advance and retreat relative to the arc center C of the large-diameter arc-shaped recess 34, 35, i.e., the axis of the steel pipe piles 74, 75, and 76.

[0036] When installing the fourth steel pipe pile 74 (outer diameter 190.7 mm), the second set of retractable collars 43, 44, 45, 46 thus formed is assembled to the anti-vibration member 22 by key engagement between the middle key groove 56a and the rear key insertion holes 32d, 33d, as shown in Figures 14 and 15. As a result, in the closed state, the inner arc-shaped circumferential surface 55a of the small-diameter arc-shaped recess 55 and the outer circumferential surface of the steel pipe pile 74 are positioned at a substantially uniform radial distance, and a small-diameter opening 57 is formed in a predetermined shape on the pivot base side. Thus, the outer circumferential surface of the fourth steel pipe pile 74 abuts substantially the entire inner arc-shaped circumferential surface 55a of the small-diameter arc-shaped recess 55, thereby suppressing vibration due to rotation. Meanwhile, when extending the steel pipe pile 74, the small-diameter opening 57 ensures a smooth movement path for opening and closing the anti-vibration member 22. Furthermore, by providing a plurality of key insertion holes 32d, 33d, the key grooves 56a can be spaced apart sufficiently, so that the strength of the support arm 56 does not become a problem.

[0037] When installing the fifth steel pipe pile 75 (outer diameter 165.2 mm), as shown in Figures 16 and 17, the front key groove 56a is reassembled into key engagement with the front key insertion holes 32d and 33d. As a result, in the closed state, the inner arc-shaped circumferential surface 55a of the small-diameter arc-shaped recess 55 and the outer circumferential surface of the steel pipe pile 75 are arranged with a gap G that is slightly wider on one circumferential side toward the rotation end due to the difference in curvature between them, which is smaller in diameter than the fourth steel pipe pile 74. However, even if such an uneven gap occurs, a necessary and sufficient contact area for holding the steel pipe pile 75 is ensured. A small-diameter opening 58 is provided in a predetermined shape on the rotation base side. Thus, the outer circumferential surface of the fifth steel pipe pile 75 abuts most of the inner arc-shaped circumferential surface 55a of the small-diameter arc-shaped recess 55, thereby suppressing swing due to rotation. On the other hand, when the steel pipe pile 75 is extended, the small diameter opening 58 ensures a clear path for opening and closing the pile.

[0038] When installing the sixth steel pipe pile 76 (outer diameter 139.8 mm), as shown in Figures 18 and 19, the rear key groove 56a is reassembled to key engagement with the rear key insertion holes 32d and 33d. In this case, the inner arc-shaped circumferential surface 55a of the small-diameter arc-shaped recess 55 and the outer circumferential surface of the steel pipe pile 76 are positioned with a larger gap G because the diameter is even smaller than that of the fifth steel pipe pile 75, but a necessary and sufficient contact area is still ensured. A small-diameter opening 59 is provided in a predetermined shape on the rotation base side. In this way, the outer circumferential surface of the sixth steel pipe pile 76 abuts most of the inner arc-shaped circumferential surface 55a of the small-diameter arc-shaped recess 55, thereby suppressing vibration due to rotation. On the other hand, when extending the steel pipe pile 76, the small-diameter opening 59 ensures a smooth flow of traffic for opening and closing the pile.

[0039] Thus, according to the pile driver 11 of the present invention, the multiple collars 39-46 provided on the anti-vibration member 22 have small-diameter arc-shaped recesses 47, 55 that can move forward and backward relative to the arc center C of the large-diameter arc-shaped recesses 34, 35, making it possible to provide an adjustment range that can accommodate multiple pile diameters with the same type of collar. This reduces the number of types of collars compared to the conventional method, which required a collar for each pile diameter, and minimizes the storage space for unused collars. Furthermore, simply operating the fixing means 49 allows the collars 39-46 to be held in their new positions, contributing to a reduction in the labor and time required for setup changes.

[0040] Furthermore, because the small-diameter arc-shaped recesses 47, 55 are eccentric to one side in the circumferential direction toward the rotation end with respect to the support arms 48, 56 that radially penetrate the large-diameter arc-shaped recesses 34, 35, it is possible to form openings 50, 53, 54, 57, 58, 59 between the small-diameter arc-shaped recesses 47, 55 that are the same type as the opening 38 formed between the large-diameter arc-shaped recesses 34, 35, eliminating unnecessary interference between the collars 39-46 and the steel pipe piles 71-76 when opening and closing the anti-vibration member 22. In particular, even in the closed state with openings formed between the collars, the arrangement space for the support arms 48, 56 is not obstructed, and a well-balanced support state can be achieved with the four support arms 48, 56 arranged at equal intervals in the circumferential direction.

[0041] Furthermore, the large-diameter arc-shaped recesses 34, 35 have arm through-holes 34d, 35d that match the cross-sectional width of the support arms 48, 56, and the small-diameter arc-shaped recesses 47, 55 use key engagement as the fastening means 49. Therefore, the rotational force of the impact applied to the support arms 48, 56 by the rotating steel pipe piles 71-76 is absorbed and mitigated by the walls of the arm through-holes 34d, 35d, limiting the direction of force transmission from the steel pipe piles 71-76 to the arm axial direction. This allows for stable key engagement through simple surface contact, despite the unique behavior of rotary piles, which are prone to fluctuations in force direction and magnitude. In particular, the structure uses multiple key grooves 48a, 56a into which the key plate 49a selectively fits, allowing for a wide range of pile diameters to be easily accommodated. In other words, the anti-vibration member 22 achieves both maintaining the connection state of the collars 39-46 and improving reassembly workability.

[0042] The present invention is not limited to the above-described embodiment, and the shape and number of retractable collars can be set as desired as long as they can hold the pile with highly stable surface contact, and modifications can be made as appropriate to the specifications of the anti-vibration members, such as configuring a set of two in addition to a set of four. Also, although the fixing means in the embodiment is key engagement, a simple pin connection or the like can also be used. [Explanation of symbols]

[0043] 11...pile driver, 12...lower running body, 13...upper rotating body, 14...base machine, 15...leader, 16...derailing cylinder, 17...leader support, 18...operator's cab, 19...equipment room, 20...top sheave, 21...steel pipe pile, 22...anti-vibration member, 23...guide pipe, 24...auger, 24a...guide gib, 25...adapter, 26...drive sprocket, 27...follower sprocket Procket, 28...lifting chain, 29...bracket, 30...first pivot shaft, 31...second pivot shaft, 32...first pivot arm, 32a...first pivot base, 32b...first pile holding portion, 32c...first connecting portion, 32d...key insertion hole, 33...second pivot arm, 33a...second pivot base, 33b...second pile holding portion, 33c...second connecting portion, 33d...key insertion hole, 34...first large diameter Arc-shaped recess, 34a...one end, 34b...other end, 34c...inner arc-shaped circumferential surface, 34d...arm through-hole, 35...second large-diameter arc-shaped recess, 35a...one end, 35b...other end, 35c...inner arc-shaped circumferential surface, 35d...arm through-hole, 36...connecting pin, 37...fixing pin, 38...large-diameter opening, 39-46...collar, 47...small-diameter arc-shaped recess, 47a...inner arc-shaped circumferential surface, 47b...plate end, 4 8...Support arm, 48a...Key groove, 48b...Side surface, 48c...Bottom surface, 49...Fixing means, 49a...Key plate, 49b...Mounting plate, 50...Small diameter opening, 51...Mounting bolt, 52...Push bolt, 53, 54...Small diameter opening, 55...Small diameter arc-shaped recess, 55a...Inner arc peripheral surface, 56...Support arm, 56a...Key groove, 57, 58, 59...Small diameter opening, 71 to 76...Steel pipe pile

Claims

1. A pile driver in which a working device is provided so as to be able to rise and fall along a leader erected at the front of a base machine, and a vibration-proof member is provided at the bottom of the leader to hold the outer peripheral surface of a steel pipe pile rotated by the working device, The anti-vibration member is provided with a pair of pivot arms having a large-diameter arc-shaped recess that can abut against the outer peripheral surface of the steel pipe pile, and is formed to be rotatable around a pair of pivot axes provided at the bottom of the leader between a closed state in which the pivot ends of the pair of pivot arms are close to each other and an open state in which they are separated, The pair of rotating arms are provided with a plurality of collars that are arranged opposite each other in the closed state and can be reassembled according to the outer diameter of the steel pipe pile, the collar has a small-diameter arc-shaped recess provided concentrically inside the large-diameter arc-shaped recess, a support arm that radially penetrates the large-diameter arc-shaped recess and supports the small-diameter arc-shaped recess so that it can advance and retreat relative to the arc center of the large-diameter arc-shaped recess, and a fixing means that fixes the small-diameter arc-shaped recess at a moving position, The support arm is rod-shaped with a rectangular cross section, and a plurality of key grooves are formed on the upper surface thereof. the large-diameter arc-shaped recess has an arm through-hole that matches the cross-sectional width of the support arm; The pile driver is characterized in that the fixing means comprises a key engagement that is fixed by fitting a key plate into the key groove.

2. In the closed state, the pair of pivot arms have an opening between the large-diameter arc-shaped recesses on the pivot base side, 2. The pile driver according to claim 1, wherein the position of the small-diameter arc-shaped recess relative to the support arm is offset toward one circumferential side toward the rotation end.

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