Pile driver

Abstract

To provide a pile driver equipped with an outrigger device that can prevent rattling during construction while ensuring transportability.SOLUTION: A pile driver comprises: a lower running body; an upper rotating body rotatably mounted on an upper part of the lower running body; a leader erected at a front of the upper rotating body; and an outrigger device 18 mounted at a rear of the upper rotating body. The outrigger device includes: an outrigger bracket 29; a pair of outrigger beams 32 connected to both left and right ends of the outrigger bracket via outrigger beam pivot pins 35 so as to be rotatable horizontally; outrigger jacks 17 mounted on each of the pair of outrigger beams; and a connecting portion 33 detachably bolting the outrigger bracket and the outrigger beam together.SELECTED DRAWING: Figure 8

Description

[Technical field]

[0001] The present invention relates to a pile driver, and more particularly to a pile driver equipped with an outrigger device at the rear of a base machine. [Background technology]

[0002] Generally, the outrigger device used in large three-point support pile drivers comprises an outrigger beam that can rotate around a support axis, an outrigger jack and a backstay fixing section, and when the pile driver is moved to the site, the outrigger beam is folded to ensure transportability (see, for example, Patent Documents 1 and 2). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 9-177074 [Patent Document 2] JP 2019-210703 A Summary of the Invention [Problem to be solved by the invention]

[0004] The above-mentioned outrigger device is used by extending the outrigger beam during pile driving construction, but when the load from the backstay is applied, the support shaft of the outrigger beam becomes loose, which can lead to the backstay and the leader supported by it becoming loose and unstable.

[0005] SUMMARY OF THE PRESENT EMBODIMENT An object of the present invention is to provide a pile driver equipped with an outrigger device that can prevent rattling during construction while ensuring transportability. [Means for solving the problem]

[0006] In order to achieve the above-mentioned object, the pile driver of the present invention is a pile driver comprising a lower running body, an upper rotating body rotatably mounted on the upper part of the lower running body, a leader erected on the front part of the upper rotating body, and an outrigger device mounted on the rear part of the upper rotating body, wherein the outrigger device has an outrigger bracket, a pair of outrigger beams connected to both left and right ends of the outrigger bracket via outrigger beam pivot pins so as to be rotatable horizontally, outrigger jacks mounted on each of the pair of outrigger beams, and a connecting portion for detachably bolting the outrigger bracket and the outrigger beam.

[0007] The connecting portion is formed by fastening opposing plate portions of the outrigger bracket and the outrigger beam together with a bolt, and in a bolt-fastened state, an axial direction of the fastening bolt is aligned with the left-right direction of the outrigger bracket. The outrigger device further includes a four-bar link mechanism having left-right ends of the outrigger bracket as fixed links, and a hydraulic cylinder for applying power to the four-bar link mechanism, the outrigger beam pivot pin forms one fulcrum of the fixed link, and the four-bar link mechanism includes a swing link that is passed between a connecting pin that forms the other fulcrum of the fixed link and the connecting pin of the hydraulic cylinder, and the outrigger bracket is provided with a swing restricting member that restricts the swing of the swing link against which it comes into contact.

[0008] In addition, the outrigger device is characterized by including a fixing member that connects and fixes the outrigger bracket and the outrigger beam when the swing of the swing link is restricted. Effect of the Invention

[0009] According to the pile driver of the present invention, the outrigger device is provided with a pair of outrigger beams rotatably connected to both left and right ends of the outrigger bracket via pivot pins, and a connecting portion for detachably fastening the outrigger bracket and the outrigger beam with bolts, so that transportability can be ensured by releasing the bolts of the connecting portion to put it in a folded state, while rattle can be prevented during construction by fastening the bolts of the connecting portion to put it in an extended state. Also, since the axial direction of the fastening bolts is aligned with the left and right direction of the outrigger bracket when the outrigger jack is in the grounded state, it is possible to effectively withstand the bending force transmitted from the outrigger beam, and the outrigger bracket and the outrigger beam can be more firmly connected to each other and put into an extended state during construction. [Brief description of the drawings]

[0010] [Figure 1] 1 is a side view of a pile driver showing one embodiment of the present invention. [Diagram 2] FIG. [Diagram 3] FIG. [Figure 4] FIG. [Diagram 5] FIG. 4 is a rear view of the main part showing the outrigger device in an extended state. [Figure 6] FIG. [Figure 7] FIG. 11 is a plan view of the main parts showing a state in which the outrigger device is in the middle of transitioning from an extended state to a folded state. [Figure 8] FIG. 4 is a plan view of the main parts showing the folded state of the outrigger device. [Figure 9] FIG. 4 is an enlarged rear view of the main part showing the outrigger device in an extended state. [Figure 10] XX cross-sectional view of Figure 9. [Figure 11] 10 is a cross-sectional view taken along line XI-XI of FIG. 9. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] 1 to 11 show an example of the present invention applied to a large pile driver of a three-point support type. As shown in Figs. 1 to 4, the pile driver 11 has a base machine (machine body) formed by mounting an upper rotating body 13 on a lower traveling body 12 equipped with crawlers so that the upper rotating body 13 can rotate. A leader bracket 16 to which a leader 14 and front jacks 15, 15 are attached is provided at the front of the upper rotating body 13, and an outrigger device 18 equipped with a pair of left and right outrigger jacks 17, 17 and a counterweight 19 mounted on the outrigger device 18 are provided at the rear end of the upper rotating body 13. Furthermore, a cab 20 and a power unit 21 equipped with a hydraulic pump driven by an engine are provided on the machine frame of the upper rotating body 13, and a gantry 22 that can be raised and lowered is provided above the rear of the upper rotating body 13.

[0012] The leader 14 is formed by connecting a plurality of leader members to the upper part of a leader base member that is attached to the leader bracket 16 so as to be tiltable in all directions, and a leader holder 23 that rotatably holds the leader 14 is provided in the middle of the leader 14. The upper ends of a pair of left and right backstays 24, 24 that are erected with their lower ends connected via stay cylinders to both ends of the outrigger unit 18 in the width direction of the machine body are connected to the rear part of the leader holder 23, and the leader 14 is supported from the rear by the backstays 24, 24.

[0013] The front side of the leader 14 is provided with a pair of guide pipes 25, 25 on the left and right, which are provided in parallel to the longitudinal direction of the leader 14, and an auger 27 which is provided so as to be able to move up and down along the front surface of the leader 14 via a guide gib 26 which slidably holds the outer surface side of each guide pipe 25, 25 in the width direction of the machine body. In the working position (FIG. 1) in which the leader 14 is erected in the vertical direction, the auger 27 grips construction members such as steel pipe piles and screw rods 28, and rotates them while burying them in the ground, thereby carrying out pile driving construction. On the other hand, in the transportation position (not shown) in which large parts such as the leader 14, the gantry 22, and the backstay 24 are disassembled, the base machine is loaded on the platform of a transport vehicle with its overall height and width reduced.

[0014] The outrigger unit 18 mainly has a rectangular box-shaped frame structure that extends in the width direction of the machine body (width direction of the upper rotating body 13) when in use, and as shown in Figure 4 etc., is configured symmetrically for stabilizing the pile driver 11, and its components (e.g. outrigger jacks 17) form a pair on the left and right. The following description will be mainly based on the figures (Figures 5 to 11) showing the right side, and an individual description of the left side will be omitted.

[0015] As shown in Figures 5 to 11, the outrigger device 18 is roughly composed of a central outrigger bracket 29, an outrigger beam 32 rotatably connected to the outrigger bracket 29 via a four-bar link mechanism 31 having a fixed link 30 at the widthwise end (right end) of the outrigger bracket 29, an outrigger jack 17 provided at the rotation base of the outrigger beam 32, a flange-type connecting portion 33 that detachably fastens the outrigger bracket 29 and the outrigger beam 32 with bolts, an outrigger beam pivot pin 35 that forms one of the fulcrums of the fixed link 30 and is provided on a vertical plane 34 that passes through the mating surfaces (hereinafter referred to as the flange mating surfaces) of the flanges (plate portions) 33a, 33b that constitute the connecting portion 33, and a hydraulic cylinder 36 that applies power to the four-bar link mechanism 31 to rotate the outrigger beam 32 horizontally around the outrigger beam pivot pin 35.

[0016] The connecting portion 33 is configured to use a plurality of fastening bolts 33c and fastening nuts 33d to bolt together the opposing flanges 33a, 33b of the outrigger bracket 29 and the outrigger beam 32, and as shown in Figure 6 and other figures, the axial direction of the fastening bolts 33c in the bolt-fastened state is aligned with the left-right direction of the outrigger bracket 29 (left-right direction in Figure 6). As a result, although not shown in the figures, when the outrigger jack 17 is in the grounded state and receives a bending force from the outrigger beam 32, a tensile force mainly in the axial direction acts on the fastening bolt 33c. Then, with the bolts at the connection parts 33 released, the hydraulic cylinder 36 is extended or retracted to rotate the outrigger beam 32, moving the outrigger jack 17 to an extended state (Figure 6) in which the outrigger bracket 29 and the outrigger beam 32 extend in a straight line in the width direction of the aircraft, or to a folded state (Figure 8) in which the outrigger jack 17 is positioned on the inside of the vertical plane 34 and the outrigger bracket 29 and the outrigger beam 32 are adjacent in the fore-aft direction.

[0017] In this embodiment, the outrigger beam 32, which displaces between the extended state and the folded state, has a rotation angle θ set to, for example, a maximum of 175 degrees (FIG. 8). Also, as shown in FIG. 5 and other figures, the position of the joint 33, in other words, the position of the vertical plane 34 defined by the flange mating surface, corresponds to the position of the outermost side surface 19a of the counterweight 19 (the position that defines the transport width). As a result, when the extended state is changed to the folded state, the outrigger beam 32 rotates nearly 180 degrees around the outrigger beam rotation pin 35, and most of the outrigger beam 32 is positioned inside the vertical plane 34, although the operating principle will be described later. At this time, the backstay fixing portion 32a provided on the upper surface of the rotating end portion (upper surface of the tip portion) of the outrigger beam 32 is replaced with the outrigger jack 17 in the machine width direction as it rotates, and is positioned from the outermost side to the innermost side beyond the vertical plane 34 (FIG. 8).

[0018] In order to make it easier to understand, the four-bar link mechanism 31 will be described with reference to Figure 7, which shows the state in which the rotation angle θ of the outrigger beam 32 from the extended state (Figure 6) is 90 degrees (an intermediate rotation angle state), and with reference to various figures including cross-sectional views as necessary (Figures 9 to 11, etc.).

[0019] As shown in FIG. 7, the four-bar link mechanism 31 is disposed at the end (right end) in the width direction of the aircraft on the rear side of the outrigger bracket 29, and basically includes an outrigger beam pivot pin 35 as a first connecting pin provided on the fixed link 30 (first fixed rib 30a) of the outrigger bracket 29, and a fixed link 30 (second fixed rib 30b) of the outrigger bracket 29, which is slightly closer to the base of the outrigger bracket 29 than the outrigger beam pivot pin 35, That is, it is composed of a second connecting pin 37 arranged slightly inward from the vertical plane 34, a rotating link 39 (first rotating rib 39a and second rotating rib 39b) having one end connected to the outrigger beam pivot pin 35 and the other end connected to the third connecting pin 38, a swing link 41 having one end connected to the second connecting pin 37 and the other end connected to the fourth connecting pin 40, and a connecting link 42 having one end connected to the third connecting pin 38 and the other end connected to the fourth connecting pin 40.

[0020] That is, the four-bar link mechanism 31 includes, as its constituent elements, a fixed link 30 formed integrally with the outrigger bracket 29, a rotating link 39 formed integrally with the outrigger beam 32, a swing link 41 and a connecting link 42 which are independent components, and first to fourth connecting pins 35, 37, 38, and 40 which serve as fulcrums for connecting these four links 30, 39, 41, and 42 via pin connections. A hydraulic cylinder 36 is attached to the rear surface of the outrigger bracket 29 via an attachment pin 43, and has an end portion (tip portion) 36a of its piston rod connected to the fourth connecting pin 40 of the four-bar link mechanism 31.

[0021] These links 30, 39, 41, 42 have differences in length and thickness, but generally have a laminated structure (a bifurcated structure on the outside) in which plates are nested vertically, and each has a pin hole at both ends. The four links 30, 39, 41, 42 are directly or indirectly connected by inserting the connecting pins 35, 37, 38, 40 into these pin holes. The pin holes of the links 30, 39, 41, 42 are indicated by the symbols 35Ha, 35Hb, 37Ha, 37Hb, 38Ha, 38Hb, 40Ha, 40Hb, corresponding to the symbols of the corresponding pins, as shown in Figures 9 and 10.

[0022] 11, the length of the line segment L1 connecting the first connecting pin 35 and the second connecting pin 37 is equal to the length of the line segment L2 connecting the first connecting pin 35 and the third connecting pin 38, and the length of the line segment L3 connecting the second connecting pin 37 and the fourth connecting pin 40 is equal to the length of the line segment L4 connecting the third connecting pin 38 and the fourth connecting pin 40. Comparing the lengths of the line segments L1 to L4, the line segments L3 and L4 are about twice as long as the line segments L1 and L2. That is, the four-bar link mechanism 31 forms a four-bar link with the links 30, 39, 41, and 42 and the connecting pins 35, 37, 38, and 40, but does not form a so-called parallel link.

[0023] 7, when the rotation angle θ of the outrigger beam 32 is 90 degrees, the links 30, 39, 41, 42 form a quadrangle with four line segments L1 to L4 as sides, the outrigger beam pivot pin 35 and the fourth connecting pin 40 are disposed diagonally, and the second connecting pin 37 and the third connecting pin 38 are disposed diagonally. When the hydraulic cylinder 36 expands and contracts, the swing link 41 swings about the second connecting pin 37 in accordance with the operation, the connecting link 42 is displaced in the direction in which the hydraulic cylinder 36 expands or contracts, and the pivot link 39 pivots about the outrigger beam pivot pin 35. As a result, the outrigger beam 32 pivots about the outrigger beam pivot pin 35 relative to the outrigger bracket 29 in response to the expansion and contraction operation of the hydraulic cylinder 36.

[0024] In this way, based on the setting of the lengths of the line segments L1 to L4 above, as shown in Figure 7, the positional relationship between the outrigger beam pivot pin 35 and the second connecting pin 37 remains unchanged, but the swing angle α of the hydraulic cylinder 36 guided by the swing of the swing link 41 is greatly increased via the pivot link 39 and the connecting link 42, and is transmitted to the outrigger beam 32 as an increased rotation angle θ.

[0025] Here, in the direction in which the hydraulic cylinder 36 extends from the intermediate rotation state (Fig. 7), as shown in Fig. 6, when the flanges 33a, 33b of the joint portion 33 come into contact with each other, the flange mating surfaces are brought into close contact with each other by obtaining relief pressure on the hydraulic circuit, and the bolt tightening work for flange connection can be performed smoothly. On the other hand, in the direction in which the hydraulic cylinder 36 contracts, as shown in Fig. 8, when the swing link 41 comes into contact with the abutment bolt (swing restricting member) 44 provided on the rear surface of the outrigger bracket 29, its swing is restricted. In this way, after the hydraulic pressure relief state is reached, a fixing member 45 is set between the outrigger bracket 29 and the outrigger beam 32, making it possible to maintain the folded state at a desired position.

[0026] In this embodiment, as shown in Fig. 11, the swing link 41 has an apex 41a on a vertical line (perpendicular bisector) that approximately bisects the line segment L3, and is formed into a generally triangular shape in plan view protruding toward the hydraulic cylinder 36, and is incorporated as a component of the four-bar link mechanism 31 in pairs (Fig. 9). On the other hand, the abutment bolts 44 serving as swing restriction members are provided in pairs (Fig. 9) at positions corresponding to the swing link 41, and the position of the bolt head can be adjusted in the front-rear direction (up-down direction in Fig. 11) by adjusting the amount of screw tightening in a block-shaped bolt attachment portion 46 that also serves to reinforce the fixed link 30 (second fixed rib 30b). The position of the abutment bolts 44 in the machine body width direction (left-right direction in Fig. 11) corresponds to the arc-shaped locus K drawn by the apex 41a of the swing link 41. As a result, as shown in FIG. 8, by adjusting the position of the abutment bolt 44 in the front-rear direction, the rotation angle θ of the outrigger beam 32 accompanying the contraction operation of the hydraulic cylinder 36 is restricted to a desired angle (for example, 175 degrees).

[0027] When the swing link 41 is in such a swing-restricted state, i.e., when the outrigger unit 18 is in a folded state, the outrigger bracket 29 and the outrigger beam 32 are connected in the front-rear direction using a rod-shaped fixing member 45. The fixing member 45 has, for example, pin holes at both bifurcated ends, and one end is attached to the central rear surface portion of the outrigger bracket 29 (the first plate piece 29a having the pin hole) via a mounting pin 47. The other end can be selectively attached via an operating pin 48 to the rear surface of the outrigger bracket 29 and to the outer side relative to the position of the first plate piece 29a (the second plate piece 29b having the pin hole) in the extended state, or to the rotating end portion of the outrigger beam 32 (the third plate piece 32b having the pin hole) in the folded state.

[0028] 5 and other figures, the fixing member 45 is held unrotatably in a position aligned along the rear surface of the outrigger bracket 29 when not in use (when the outrigger device 18 is in an extended state), whereas when in use (when the outrigger device 18 is in a folded state), it is rotated rearward about the mounting pin 47. Accompanying this rotation operation, the operating pin 48 is displaced from the outrigger bracket 29 (second plate piece 29b) to the outrigger beam 32 (third plate piece 32b). As a result, even in a situation where hydraulic retention cannot be obtained (for example, during transportation), the fixing function of the fixing member 45 is exerted and the outrigger beam 32 is fixed in that position, and outward rotation toward the extended state is restricted.

[0029] As described above, according to the pile driver 11 of the present invention, the outrigger device 18 includes a pair of outrigger beams 32 rotatably connected to both left and right ends of the outrigger bracket 29 via the pivot pins 35, and a connecting portion 33 that detachably fastens the outrigger bracket 29 and the outrigger beam 32 with bolts, so that transportability can be ensured by releasing the bolts of the connecting portion 33 to put it in a folded state, while rattle during construction can be prevented by fastening the bolts of the connecting portion 33 to put it in an extended state. Also, since the axial direction of the fastening bolts 33c is aligned with the left and right direction of the outrigger bracket 29 when the outrigger jack 17 is in the grounded state, it is possible to favorably withstand the bending force transmitted from the outrigger beam 32, and the outrigger bracket 29 and the outrigger beam 32 can be more firmly connected to each other and put in an extended state during construction.

[0030] Furthermore, since the four-bar link mechanism 31 is provided, the outrigger beam 32 can be configured to have a wide range of rotation, and can be easily powered by providing the hydraulic cylinder 36, ensuring good transportability, for example, when the outrigger beam 32 is in a folded state rotated nearly 180 degrees. Moreover, the four-bar link mechanism 31 includes a swing link 41 that is stretched between the connecting pin (second connecting pin) 37 that forms the other fulcrum of the fixed link 30 and the connecting pin (fourth connecting pin) 40 of the hydraulic cylinder 36, and the outrigger bracket 29 is provided with a swing restriction member (e.g., abutment bolt) 44 that the swing link 41 abuts against to restrict its swing, so that the outrigger beam 32, which operates using hydraulic pressure, can be accurately positioned.

[0031] Furthermore, since the fixing member 45 that connects and fixes the outrigger bracket 29 and the outrigger beam 32 is provided in a state in which the swing of the swing link 41 is restricted by the swing restricting member 44, the stability of the folded state can be improved. In particular, by applying an abutment bolt to the swing restricting member 44 and a pin connection structure to the fixing member 45, the adjustment of the rotation angle θ of the outrigger beam 32 and the fixing work can be performed efficiently by simple means, which also contributes to improving operability.

[0032] The present invention is not limited to the above-mentioned embodiment, and the configuration and arrangement of the outrigger device can be appropriately changed according to the specifications of the pile driver. In the embodiment, the position of the joint corresponds to the outer surface of the counterweight to improve the workability of fastening and releasing the bolt, but the present invention is not limited to this, and the position of the joint may be changed within a range that ensures transportability. Furthermore, the number of fastening bolts used and their arrangement (direction) that constitute the joint can be determined arbitrarily. In addition, various configurations can be adopted for the specific configuration of the four-bar link mechanism and the configuration of each member such as the swing restricting member and the fixing member as long as they are suitable for the operation and purpose. [Explanation of symbols]

[0033] 11...pile driver, 12...lower running body, 13...upper rotating body, 14...leader, 15...front jack, 16...leader bracket, 17...outrigger jack, 18...outrigger device, 19...counterweight, 19a...outermost surface, 20...operator cab, 21...power section, 22...gantry, 23...leader holder, 24...backstay, 25...guide pipe, 26...guide gib, 27...auger, 28...screw rod, 29...outrigger bracket, 29a...first plate piece, 29b...second plate piece, 30...fixed link, 30a...first fixed rib, 30b...second fixed rib, 31...four-section link mechanism, 32...outrigger beam, 32a...backstay fixing section, 32b... Third plate portion, 33...connecting portion, 33a, 33b...flange, 33c...fastening bolt, 33d...fastening nut, 34...vertical surface, 35...outrigger beam pivot pin (first connecting pin), 35Ha, 35Hb...pin hole, 36...hydraulic cylinder, 36a...terminal portion, 37...second connecting pin, 37Ha, 37Hb...pin hole, 38...third connecting pin, 38Ha, 38Hb...pin hole, 39...rotating link, 39a...first pivot rib, 39b...second pivot rib, 40...fourth connecting pin, 40Ha, 40Hb...pin hole, 41...swinging link, 41a...top portion, 42...connecting link, 43...mounting pin, 44...contact bolt, 45...fixing member, 46...bolt mounting portion, 47...mounting pin, 48...operating pin

Claims

1. A pile driver including a lower traveling body, an upper rotating body rotatably provided on an upper portion of the lower traveling body, a leader provided in an upright position on a front portion of the upper rotating body, and an outrigger device provided on a rear portion of the upper rotating body, The outrigger device is a pile driver characterized in that it comprises an outrigger bracket, a pair of outrigger beams connected to both left and right ends of the outrigger bracket via outrigger beam pivot pins so that they can rotate horizontally, outrigger jacks provided on each of the pair of outrigger beams, and a connecting portion that bolts together the outrigger bracket and the outrigger beam in a detachable manner.

2. The pile driver described in claim 1, characterized in that the connection portion is formed by bolting together the facing plate portions of the outrigger bracket and the outrigger beam, and when in the bolt-fastened state, the axial direction of the fastening bolts is aligned with the left-right direction of the outrigger bracket.

3. The outrigger device includes a four-bar link mechanism having left and right ends of the outrigger bracket as fixed links, and a hydraulic cylinder for applying power to the four-bar link mechanism, The four-bar link mechanism includes a swing link that is stretched between a connecting pin that forms one fulcrum of the fixed link and a connecting pin of the hydraulic cylinder, the outrigger beam pivot pin forming one fulcrum of the fixed link, and the connecting pin of the hydraulic cylinder, 3. The pile driver according to claim 1, wherein the outrigger bracket is provided with a swing restricting member that restricts the swing of the swing link against which the swing link abuts.

4. 4. The pile driver according to claim 3, wherein the outrigger device includes a fixing member that connects and fixes the outrigger bracket and the outrigger beam when the swinging of the swing link is restricted.

Images