Pile driver

Abstract

To provide a pile driver capable of achieving improvement in workability at the time of assembly and disassembly of a leader, while securing cable wiring to a leader apex.SOLUTION: In a pile driver in which at an apex of a leader 15, a detection part 38 for detecting an operation state of a work device 37 is provided, the leader comprises a plurality of leader members 27c that are detachably connected with each other. In a leader lifting ladder 21 provided on a side surface of the leader, a plurality of ladder members 22 is provided continuously by having an interval with each other on the side surface of the leader, in a state where the plurality of leader members is connected. The ladder member includes a muntin comprising a pair of cylindrical members 22a, 22a provided along the longer direction of the leader. A cable 40 from the detection part is held receiving an elastic force acting in the cylindrical member radial direction from an elastic member 43 press-fitted in an opening of the cylindrical member, in a state of being passed through the cylindrical member.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a pile driver, and more particularly to a pile driver equipped with a detection unit at the top of a leader that detects the operating state of a working implement. [Background technology]

[0002] In pile drivers equipped with a leader that guides the lifting and lowering of the working equipment, the lifting range of the working equipment is limited for safety reasons. For example, on the rising side, a switch that detects the operating state of the working equipment is attached to the top of the leader, and when this switch detects the lifting operation of the working equipment, the working equipment is stopped by cutting off the hydraulic circuit (for example, see Patent Documents 1 and 2). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2011-149189 A [Patent Document 2] JP 2015-121071 A Summary of the Invention [Problem to be solved by the invention]

[0004] The pile driver described above uses a ladder on the side of the leader as a place to place and secure the cable (electric wire) from the switch. However, if the cable is placed along the ladder that serves as the scaffold, the number of cable ties increases excessively in terms of the safety of the worker in ascending and descending and the protection of the cable, which results in a problem of reduced workability when assembling or disassembling to change the leader length.

[0005] SUMMARY OF THE PRESENT EMBODIMENT An object of the present invention is to provide a pile driver that can improve workability when assembling and disassembling the leader while ensuring cable wiring to the top of the leader. [Means for solving the problem]

[0006] In order to achieve the above-mentioned object, the pile driver of the present invention comprises a leader that is arranged to be able to rise and fall on the front of a base machine, a working device that is attached to the front of the leader so that it can be raised and lowered, and a leader climbing ladder that is arranged on the side of the leader, and a detection unit that detects the operating state of the working device is provided on the top of the leader, wherein the leader is formed by removably connecting a plurality of leader members to each other, and the leader climbing ladder is arranged such that, when the plurality of leader members are connected, a plurality of ladder members are arranged in a row at intervals from each other on the side of the leader, the ladder members have vertical bars consisting of a pair of tubular members arranged along the longitudinal direction of the leader, and a cable from the detection unit is passed through the tubular member and held in place by an elastic force acting in the radial direction of the tubular member from an elastic member pressed into an opening of the tubular member.

[0007] The elastic member is characterized in that it has a hole to which the cable is tightly attached and a notch that communicates with the hole from the side surface. Furthermore, the elastic member is characterized in that the outer diameter of the inner end portion in the press-fitting direction relative to the opening is smaller than the diameter of the opening, and the outer diameter of the inner end portion in the press-fitting direction is larger than the diameter.

[0008] The side surface of the elastic member is inclined so that the diameter gradually increases from the rear end toward the front end in the press-fitting direction. The cable is provided with a connector that connects the cable in the space between the ladder members, and the outer diameter of the connector is smaller than the inner diameter of the tubular member. Effect of the Invention

[0009] According to the pile driver of the present invention, when a detector for detecting the operating state of the working device is provided at the top of the leader, the cable from the detector is passed through the tubular member constituting the vertical rail of the leader climbing ladder, and in this state, the cable is held by the elastic force acting in the radial direction of the tubular member from the elastic member pressed into the opening of the tubular member, so that a fixing method that is simple yet preferable in terms of cable protection and has a good appearance can be obtained. In particular, compared to the conventional method using cable ties, the number of fixing points of the cable can be reduced, and the cable can be held corresponding to the connection parts between the leader members, so that the workability can be improved when assembling or disassembling for the purpose of changing the leader length.

[0010] In addition, the elastic member has a hole where the cable fits tightly and a notch that connects from the side to the hole, so that the cable can be easily inserted and removed from the hole through the notch.Furthermore, the outer diameter of the end at the back side in the press-fitting direction is smaller than the diameter of the opening of the tubular member, and the outer diameter of the end at the front side in the press-fitting direction is larger.This prevents the elastic member from becoming buried in the opening, thereby further improving workability and quality stability.

[0011] In addition, because the side of the elastic member is inclined, the elastic force acting in the radial direction of the tubular member when subjected to a force in the pressing direction is greatly increased, improving the adhesion of the cable to the hole. Furthermore, a connector is provided to relay the cable in the space between the ladder members, and the outer diameter of this connector is made smaller than the inner diameter of the tubular member, so the amount of work required to hold the cable can be reduced when disassembling and transporting the pile driver or changing specifications by rearranging the leader members. Moreover, even if it becomes necessary to relocate the connector for just one leader member, this can be done simply by passing the connector through the tubular member, which is highly efficient and can be widely applied to a variety of environments at pile construction sites. [Brief description of the drawings]

[0012] [Figure 1] 1 is a side view of a pile driver showing one embodiment of the present invention. [Diagram 2] FIG. [Diagram 3] This is an oblique view showing the space between the ladder members in the leader ladder. [Figure 4] FIG. [Diagram 5] FIG. [Figure 6] FIG. [Figure 7] FIG. 11 is a cross-sectional side view of a main portion showing a state in which a cable is held by an elastic member. [Figure 8] FIG. 11 is a perspective view showing the space between the ladder members with the cable held by the elastic member. [Figure 9] FIG. 11 is a perspective view showing the state in which a cable connector is arranged in the space between the ladder members. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] 1 to 9 are diagrams showing the pile driver of the present invention. As shown in FIG. 1, the pile driver 11 includes a base machine 14 including a lower traveling body 12 equipped with crawlers and an upper rotating body 13 rotatably mounted on the lower traveling body 12, a leader 15 erected at the front of the upper rotating body 13, and a hoisting cylinder 16 supporting the leader 15 from the rear. A leader support 17 supporting the leader 15 so that it can be raised and lowered is provided at the front of the upper rotating body 13, and a piping support member 18 supporting hydraulic piping and the like at the rear of the leader 15 is provided above the front of the upper rotating body 13. Stabilizing jacks 19 are provided at four locations on the front, rear, left and right of the upper rotating body 13, and a counterweight 20 for balancing the pile driver 11 is mounted at the rear end of the upper rotating body 13.

[0014] The leader 15 is made up of multiple leader members each having a rectangular cylindrical cross section that are detachably connected to each other, and is provided with a leader ladder 21 on the left and right sides (the opposite right side is not shown) which is made up of multiple ladder members 22 spaced apart from one another. A cylinder bracket 23 is provided on the rear side of the leader 15, and the cylinder rod of the hoisting cylinder 16 is connected to the cylinder bracket 23. This allows the hoisting cylinder 16 to be extended and retracted to change the position of the leader 15 between a vertically standing position in front of the base machine 14 (FIG. 1) and a position where the leader 15 and the hoisting cylinder 16 are both laid down on the base machine 14 (not shown).

[0015] In addition, the leader 15 is divided into a lower leader 25 rotatably attached to a support shaft 24 in the base machine width direction provided on the leader support 17, an intermediate leader 26 connected to the upper part of the lower leader 25, and an upper leader 27 connected to the upper part of the intermediate leader 26, and further, the lower leader 25 is divided into a lower first leader member 25a and a lower second leader member 25b, the intermediate leader 26 is divided into an intermediate first leader member 26a and an intermediate second leader member 26b, and the upper leader 27 is divided into an upper first leader member 27a, an upper second leader member 27b, and an upper third leader member 27c.

[0016] As an example of the leader member, Fig. 2 shows the upper first leader member 27a in a component state, and Fig. 3 shows the connection portion between the upper first leader member 27a and the upper second leader member 27b. Each leader member has a flange connection portion 28 in which the connecting flanges 28a, 28a of a substantially rectangular ring shape corresponding to the cross-sectional shape of the leader 15 are abutted against each other at the adjacent portion and connected to each other with a plurality of bolts 29 and nuts 30. Each flange connection portion 28 has the same structure with the same shape of the connecting flanges 28a, the size of the bolt holes, the arrangement pitch, etc., and by removing the bolts 29 and nuts 30 to release the flange connection, it is possible to reassemble the leader members into a long specification (Fig. 1) consisting of a large number of leader members, for example, the upper leader 27 consisting of three members, the upper first leader member 27a, the upper second leader member 27b, and the upper third leader member 27c, and a short specification (not shown) consisting of a small number of leader members, for example, excluding the upper leader 27.

[0017] As can be seen from Fig. 1, each ladder member 22 basically has a length corresponding to the length of each leader member, and as shown in Fig. 2, a pair of vertical bars 22a, 22a arranged parallel to each other along the longitudinal direction of the leader member 27a (the vertical direction in Fig. 2) and a plurality of horizontal bars 22b connecting the pair of vertical bars 22a, 22a constitute the ladder body, and the ladder body has a plurality of fixing members 22c for fixing the ladder body to the side of the leader member 27a. The ladder body (vertical bars 22a and horizontal bars 22b) is made of a cylindrical member (hollow round pipe) having a circular cross section to reduce weight. Also, as shown in Fig. 3, when the leader members 27a, 27b are connected to each other, a space S is created between the ladder members 22, 22, and in this state, all of the cylindrical members 22a, 22a extending in a row in the longitudinal direction are arranged on the same axis. That is, one opening (upper end opening) 31 and the other opening (lower end opening) 32 of the cylindrical members 22a, 22a adjacent in the longitudinal direction are disposed facing each other. Furthermore, since the length of the fixing member 22c (the distance between the side surface of the leader member 27a and the vertical bar 22a) is formed longer than the width of the connecting flange 28a (the distance between the side surface of the leader member 27a and the outer end of the connecting flange 28a), there is nothing to obstruct between the opposing openings, and the cables 40, 41 described later can be smoothly arranged.

[0018] A top sheave block 33 is attached to the top (upper end) of the upper leader 27, and although not shown, a rope for hoisting construction piles and the like is hung over the sheave. Meanwhile, a vibration-proof member 34 is attached to the lower front of the lower leader 25 to prevent the rotating construction piles and the like from vibrating. In addition, a rack gear 35 consisting of multiple rack gear members 35a is provided in the center of the front surface of the leader 15 as a component of the rack and pinion type lifting device, and a pair of left and right guide pipes 36, 36 consisting of multiple guide pipe members 36a are provided continuously over the entire length of the leader 15 at the front ends of both sides.

[0019] The auger 37, which is an example of a working device, has a pair of left and right guide gibs 37a, 37a that slide against the guide pipes 36, 36 and are provided protruding rearward, and a pair of left and right pinions that mesh with tooth rows provided on both sides of the rack gear 35 are rotated by an auger lifting hydraulic motor (not shown), so that the auger 37 moves up and down along the front surface of the leader 15. When the pile driver 11 is used at a construction site, for example, a steel pipe pile is used as the construction member. Although not shown, the steel pipe pile is connected to the lower end of the output shaft of the auger 37 via an adapter, and rotates when driven by the auger drive hydraulic motor 37b. In this rotating state, the auger 37 is lowered to be buried in the ground.

[0020] For safety reasons, the pile driver 11 configured in this manner has a limit set on the lifting range of the auger 37. For example, on the rising side, a switch is attached to the top of the leader 15 as a detector for detecting the operating state of the auger 37 so that the auger 37 does not collide with the top sheave block 33. When this switch detects the rising movement of the auger 37, it cuts off the hydraulic circuit to stop the auger 37.

[0021] 4 and 5, the switch 38 is a normally closed limit switch, and is provided with a dog plate 39 that is pushed up by the upward movement of the auger 37, and transmits the movement of the dog plate 39 acting on a roller arm type actuator (not shown) to the built-in switch. The switch 38 and its related parts are attached integrally to the flange-shaped mounting plate 33a of the top sheave block 33, and the specific mounting structure is substantially the same as that described in Patent Document 2.

[0022] The switch 38 uses a cab-tire cable 40 (hereinafter simply referred to as cable) in which two electric wires (signal wires) connected to the terminals are covered with a protective tube, and is connected to a cable 41 drawn from the main frame of the upper rotating body 13 via a relay connector (male side 42a, female side 42b) 42. The cable length is set according to the long length specification of the reader 15, and the cable 40 from the switch 38 is, for example, 7.5 m, and the cable 41 from the main frame is, for example, 15 m.

[0023] Incidentally, the leader ladder 21 has been used conventionally as a place to arrange and fix the cables 40, 41. However, if the cables 40, 41 are placed along the ladder body that serves as the scaffolding, the number of cable ties increases excessively from the viewpoint of the safety of the worker ascent and descent and the protection of the cables, resulting in a problem of reduced workability when assembling and disassembling the leader 15.

[0024] Therefore, in the pile driver 11 of the present invention, the cables 40, 41 of the switch 38 are passed through the tubular members (vertical bars) 22a of the ladder body as shown in Figures 4, 8, and 9, and are held in this wiring state by elastic members (rubber) 43 pressed into the openings (upper end openings) 31 of each tubular member 22a. For example, five elastic members 43 are used, one for each of the leader members 26a, 26b, 27a, 27b, and 27c of the intermediate leader 26 and the upper leader 27. In addition, the tubular member 22a to which the cable is wired is the right hand side of the pair of tubular members 22a, 22a in the ladder member 22 on the left side of the leader 15, that is, the side farthest from the auger 37. This allows the free portion of the cable 40 to be separated from the guide gib 37a when the auger 37 is at the upper limit position (FIG. 4) while ensuring the safety of the worker using the leader climbing ladder 21.

[0025] The elastic member 43 is a rubber molded product in a truncated cone shape, and as shown in Fig. 6 and Fig. 7, each dimension including the height H corresponding to the press-fitting direction (downward in Fig. 7) is determined in consideration of elastic deformation due to press-fitting, adhesion with the cables 40, 41, and the influence of mechanical vibration. In relation to the upper end opening 31 of the cylindrical member 22a, the outer diameter d1 of the press-fitting direction back end 43a relative to the opening 31 is smaller than the aperture of the opening 31 (the inner diameter of the cylindrical member 22a), and the outer diameter d2 of the press-fitting direction front end 43b is larger than the aperture. Based on such outer diameter dimensions, the side surface (outer peripheral surface) 43c of the elastic member 43 is inclined so that the diameter gradually increases from the press-fitting direction back end 43a toward the press-fitting direction front end 43b.

[0026] The elastic member 43 is provided with a hole 43d penetrating the center and a notch 43e communicating from the side surface 43c to the hole 43d. The hole 43d is formed slightly larger than the outer diameter of the cables 40, 41, and when the cables 40, 41 are inserted through the notch 43e, the peripheral surfaces of the hole 43d and the cables 40, 41 are lightly in contact with each other. Then, when the elastic member 43 is slid relative to the cables 40, 41 to adjust the position, the elastic member 43 is pressed into the opening 31, and the cables 40, 41 are brought into close contact with the hole 43d by the elastic force acting from the elastic member 43 in the radial direction of the cylindrical member (the left-right direction in FIG. 7), and as a result, the cables 40, 41 are stably held in the opening 31. At this time, the front end 43b in the press-in direction is positioned outside the opening 31 by the amount of protrusion L, and a fingertip hold is provided when removing the elastic member 43 from the opening 31.

[0027] Here, the connector 42 used in this embodiment is a general waterproof wiring connector, but has an outer diameter (maximum diameter) smaller than the inner diameter of the cylindrical member 22a, and by making it this size, the cables 40, 41 and the connector 42 can pass through the cylindrical member 22a as a unit. In addition, the arrangement of the connector 42 corresponds to any position of a plurality of flange coupling parts 28 belonging to the upper leader 27, for example, the position of the flange coupling part 28 between the upper first leader member 27a and the upper second leader member 27b as shown in FIG. 9. In other words, the connector 42 relays the cables 40, 41 in the space S between the ladder members 22, 22.

[0028] When transporting the pile driver 11 configured in this manner, heavy objects such as the auger 37 and the counterweight 20 are removed as necessary. In addition, for example, the upper second leader member 27b and the upper third leader member 27c of the long leader 15 are disassembled from the components of the upper leader 27, and transported in their component states. In this case, the connector 42 is released from the connection state, and the cable 40 from the switch 38 is pulled out from the hollow cylindrical member 22a from which the elastic member 43 has been removed, and then bundled up at an appropriate position of the top sheave block 33. On the other hand, the cable 41 from the main frame is cabled to the ladder member 22 at the tip of the upper first leader member 27a, and the connector (male side 42a) 42 is left behind. Then, after each leader member 27b, 27c is disassembled in a predetermined procedure, each leader member 27b, 27c and the base machine 14 are transported separately. The series of operations is basically performed with the reader 15 laid horizontally on the base machine 14.

[0029] When assembling the pile driver 11 at the site, the above-mentioned disassembly procedure is performed in reverse. In this case, the leader 15 is kept in a horizontal state, and the upper second leader member 27b is connected to the upper first leader member 27a, and then the upper third leader member 27c and the top sheave block 33 are connected in this order. Here, in each leader member 27b, 27c, a cable 40 from a switch 38 is passed through a cylindrical member (vertical crosspiece) 22a of the ladder body, and a connector 42 is connected in a space S between the ladder members 22, 22. The excess length of the cable 40 is gathered in the top sheave block 33. Finally, when an elastic member 43 is pressed into the upper end opening 31 of each cylindrical member 22a, the cable wiring work in the leader 15 is completed. When the leader 15 is placed vertically upright (FIG. 1), as shown in FIGS. 8 and 9, the elastic member 43 exerts a clamping function to hold the cables 40, 41, thereby preventing the cables 40, 41 from falling or becoming displaced.

[0030] In this way, according to the pile driver 11 of the present invention, when a detector (switch) 38 for detecting the operating state of the working device is provided at the top of the leader 15, the cables 40, 41 from the detector 38 are passed through the cylindrical member 22a constituting the vertical rail of the leader climbing ladder 21, and in this state, the cables are held by receiving an elastic force acting in the radial direction of the cylindrical member from the elastic member (rubber) 43 pressed into the opening 31 of the cylindrical member 22a, so that a fixing method that is simple yet preferable in terms of cable protection and has a good appearance can be obtained. In particular, compared to the conventional method using cable ties, the number of fixing points of the cables 40, 41 can be reduced, and cable holding corresponding to the connection part (flange connection part) 28 between the leader members can be performed, so that the workability can be improved when assembling or disassembling for the purpose of changing the leader length.

[0031] Furthermore, the elastic member 43 is provided with a hole 43d to which the cables 40, 41 are in close contact, and a notch 43e that connects from the side surface 43c to the hole 43d, so that the cables 40, 41 can be easily inserted and removed from the hole 43d through the notch 43e. Furthermore, the outer diameter of the rear end 43a in the press-fitting direction is made smaller and the outer diameter of the front end 43b in the press-fitting direction is made larger than the diameter of the opening 31 of the tubular member 22a, so that the elastic member 43 can be prevented from becoming buried in the opening 31, thereby further improving workability and quality stability.

[0032] In addition, since the side surface 43c of the elastic member 43 is inclined, the elastic force acting in the radial direction of the cylindrical member when receiving the force in the press-in direction is greatly increased, and the adhesion of the cables 40, 41 to the hole 43d can be improved. Furthermore, a connector 42 is provided to relay the cables 40, 41 in the space S between the ladder members 22, 22, and the outer diameter of this connector 42 is formed smaller than the inner diameter of the cylindrical member 22a, so that the amount of work required to hold the cables can be reduced when disassembling and transporting the pile driver 11 or changing the specifications by rearranging the leader members. Moreover, even if it becomes necessary to relocate the connector 42 for only one leader member, this can be achieved by a simple method of passing the connector 42 through the cylindrical member 22a, which provides excellent work efficiency and can be widely applied to various environments at pile construction sites.

[0033] The present invention is not limited to the above-mentioned embodiment, and the detector for detecting the operating state of the working device may be a limit switch or a potentiometer for detecting the rotation angle, and may be modified as appropriate according to the driving method of the working device and the purpose of construction management. The cable wiring is not particularly limited as long as the hollow part of the ladder body is used, and the connector may be arranged arbitrarily. The elastic member may be made of other materials having rubber elasticity, and if the cylindrical member is made of a square pipe, it may be a block body corresponding to the square pipe. In particular, the elastic member of the embodiment has a very simple shape and is easy to manufacture, but it can be made into various shapes as follows. For example, it can be formed by combining two symmetrical half bodies. In addition, if the front end in the press-in direction (corresponding to the protrusion amount L in the embodiment) is made into a flange shape that is widened in the radial direction and matched to the outer diameter of the cylindrical member, it is possible to reliably prevent it from being buried in the opening and to make it easy to attach and detach. Furthermore, it is possible to eliminate the inclination of the side surface, provide a rib (protruding portion), or widen the width of the cut. [Explanation of symbols]

[0034] Reference Signs List 11...pile driver, 12...lower running body, 13...upper rotating body, 14...base machine, 15...leader, 16...dering cylinder, 17...leader support, 18...pipe support member, 19...jack, 20...counterweight, 21...leader climbing ladder, 22...ladder member, 22a...vertical crosspiece (cylindrical member), 22b...horizontal crosspiece, 22c...fixing member, 23...cylinder bracket, 24...support shaft, 25...lower leader, 25a...lower first leader member, 25b...lower second leader member, 26...middle leader, 26a...middle first leader member, 26b...middle second leader member, 27...upper leader, 27a...upper first leader member, 27b...upper second leader member, 27c...upper Third leader member, 28... flange joint portion, 28a... connecting flange, 29... bolt, 30... nut, 31, 32... opening, 33... top sheave block, 33a... mounting plate, 34... anti-vibration member, 35... rack gear, 35a... rack gear member, 36... guide pipe, 36a... guide pipe member, 37... auger, 37a... guide gib, 37b... hydraulic motor for driving auger, 38... switch, 39... dog plate, 40, 41... cable, 42... connector, 42a... male connector, 42b... female connector, 43... elastic member, 43a... rear end in press-fit direction, 43b... front end in press-fit direction, 43c... side surface, 43d... hole, 43e... notch

Claims

1. A pile driver including a leader that is provided at the front of a base machine so as to be able to rise and fall, a work device that is attached to the front of the leader so as to be able to rise and fall, and a leader climbing ladder that is provided on the side of the leader, and a detection unit that detects the operating state of the work device is provided at the top of the leader, The leader is formed by detachably connecting a plurality of leader members to each other, The leader climbing ladder is provided with a plurality of ladder members arranged at intervals on the side surface of the leader with the leader members connected together, The ladder member has a pair of vertical bars formed of cylindrical members arranged along the longitudinal direction of the leader, This pile driver is characterized in that the cable from the detection unit is passed through the tubular member and held therein by an elastic force acting in the radial direction of the tubular member from an elastic member pressed into the opening of the tubular member.

2. 2. The pile driver according to claim 1, wherein the elastic member is provided with a hole into which the cable is tightly fitted and a notch that communicates with the hole from a side surface.

3. The pile driver according to claim 2, characterized in that the outer diameter of the elastic member at the rear end in the pressing-in direction relative to the opening is smaller than the diameter of the opening, and the outer diameter of the elastic member at the front end in the pressing-in direction is larger than the diameter.

4. 4. The pile driver according to claim 3, wherein the side surface of the elastic member is inclined so that the diameter gradually increases from the rear end in the pressing-in direction to the front end in the pressing-in direction.

5. The cable is provided with a connector that relays the cable in the space between the ladder members, 5. The pile driver according to claim 1, wherein an outer diameter of the connector is smaller than an inner diameter of the tubular member.

Images