JP4714724B2 - Hammer grab - Google Patents

Description

  The present invention relates to a hammer grab used for excavating and excavating the inside of a casing in a cast-in-place pile method or other foundation work or for picking up a ready-made pile cut or crushed by an appropriate means.

  Conventionally, in the cast-in-place pile method and other foundation works, means for excavating a steel pipe as a casing driven into the ground using a hammer grab has been used. For example, as shown in the working state diagram of FIG. 12, a casing (steel pipe) C is driven into the ground G by using an all-round rotation drive device A, and a hammer grab is suspended by a suspension wire E hanging from the tip of a jib D of a crane B. H is suspended and lowered into the casing C, and the shell F is opened and closed to perform underground excavation and earth removal work.

Although the details of the conventional hammer grab are omitted, a plurality of (typically a pair) curved scoop-shaped shells as a bucket are pivotally attached to the lower end so as to be openable and closable. By dropping, push the shell into the earth and sand layer, then change the shell to the closed position, scoop up the earth and sand, hold the earth and sand between the closed shells, pull up the whole, and make the shell open position on the ground The earth and sand are discharged (for example, Patent Documents 1 to 3). In addition, for obstacles such as rocks in the casing and existing piles that have been cut or crushed by appropriate means, a hammer grab is used to grip the shell inwardly from the open position to the closed position. In this state, a method is adopted in which the hammer grab is pulled up to the ground by pulling up.
JP-A-7-11859 JP 2004-76361 A JP 2006-348469 A

  However, with a conventional hammer grab, in parallel to the rotary excavation of the cylindrical casing, the inner obstacle such as excavated soil and rock is grasped, or the rotary cylinder is cut into the driven casing. Inserting together with the machine and crushing machine, cutting the embedded obstacles such as existing piles with the cutting machine, and crushing underground concrete structures with the crushing machine, etc. In many cases, the hammer grab rotates in contact with the rotating casing, cutting machine, and crusher, and the hydraulic piping tube and power connected to the shell drive mechanism from the ground side by this rotation. Cables, wires, etc. could be twisted and cut.

  In view of the circumstances as described above, the present invention, as a hammer grab, grasps excavated soil and buried obstacles in parallel with the rotary excavation of the casing, or rotates the cylindrical cutter or crushing in the casing. When loading together with the machine and grabbing the cut or crushed material, even if it comes into contact with the rotating casing, cutting machine, or crusher, it will not rotate as a whole. It is an object of the present invention to provide a hammer grab that can surely prevent a connected hydraulic piping tube, power cable, wire, etc. from being twisted and cut.

  Means for solving the above problems will be described with reference numerals of the embodiments described later. The invention according to claim 1 is configured such that the shell mounting frame 3 is fixed to the lower end portion of the cylindrical base frame 2, and the shell A plurality of shells 4 are pivotally attached to the mounting frame 3, and a cylinder 5 for opening and closing the shell is concentrically disposed in the cylindrical base frame 2, and the elevating frame 6 is moved up and down at the lower part in the cylindrical base frame 2. The lower end side of the cylinder 5 is connected to a connecting rod 8 concentrically mounted in the elevating frame 6 via a bearing 7 so as to be relatively rotatable, and an inner shaft body 9 a is connected to the upper end side of the cylinder 5. And the inner shaft body 9a of the swivel mechanism 9 consisting of an outer cylinder body 9b that is rotatably fitted to the outer cylinder body 9b, and concentrically connects the outer cylinder body 9b to the cylindrical base frame 2 side, A suspension connection portion 10 is provided on the upper end side of the inner shaft body 9a, and the lifting frame 6 and the shells 4 and 4 are connected to each other. Interlocking connected by click mechanism 12, and characterized by being so as to open and close the shell 4,4 by the lifting of the lifting frame 6 by stretching operation of the cylinder 5.

  A second aspect of the present invention is the hammer grab according to the first aspect, wherein the cylindrical base frame 2 can move forward and backward in the outward radial direction from the center side with respect to the inner peripheral surface of the casing C driven into the ground. A stabilizer 29 having a pusher 28 for integrating the cylindrical base frame 2 with the casing C in pressure contact with the inner peripheral surface of the casing C during forward movement is integrally provided.

  According to a third aspect of the present invention, in the hammer grab according to the first or second aspect, a plurality of sheaves 26 are juxtaposed on the suspension connection portion 10, and suspension wires 27 are hung on the sheaves 26. It is characterized by becoming like this.

  The hammer grab according to claim 4 has a shell mounting frame 3 fixed to the lower end of the cylindrical base frame 2, a plurality of shells 4 are pivotally attached to the shell mounting frame 3, and the shell is opened and closed in the cylindrical base frame 2. The driving cylinder 5 is arranged concentrically, and an elevating frame 6 is provided at the lower part of the cylindrical base frame 2 so as to be movable up and down, and the elevating frame 6 is concentrically connected to the lower end side of the cylinder 5. An inner shaft body 9a of a swivel mechanism 9 comprising an inner shaft body 9a and an outer cylinder body 9b rotatably fitted to the inner shaft body 9a is concentrically connected to the upper end side of the cylinder 5, and the upper end side of the cylinder 5 is connected to the cylinder. The suspension frame 10 is fixed to the side of the base frame 2, a hanging connection portion 10 is provided on the outer cylinder body 9 b of the swivel mechanism 9, the lifting frame 6 and the shell 4 are interlocked and connected by a link mechanism 12, The shell 4 is opened and closed by raising and lowering the lifting frame 6 by And features.

  According to a fifth aspect of the present invention, in the hammer grab according to the fourth aspect, the cylindrical base frame 2 can move forward and backward in the outward radial direction from the center side with respect to the inner peripheral surface of the casing C driven into the ground. A stabilizer 49 having a pusher 28 for integrating the cylindrical base frame 2 with the casing C while being pressed against the inner peripheral surface of the casing C at the time of forward movement is integrally provided.

  A sixth aspect of the present invention is the hammer grab according to the fourth or fifth aspect, wherein a plurality of sheaves 26 are juxtaposed on the suspension connecting portion 10 and suspension wires 27 are hung on the sheaves 26. It is characterized by becoming like this.

  The effect of the invention by the above-described solution means will be described with reference numerals of the embodiments described later. According to the invention according to claim 1, the cylindrical base frame 2, the shell mounting frame 3, the shell 4, and the lifting frame 6 An inner shaft of the swivel mechanism 9 connected to the upper end side of the cylinder 5 for connecting and closing the cylinder opening and closing drive cylinder 5, the connecting rod 8 disposed in the cylindrical base frame 2. The other series of members 5, 8, 9 a composed of the body 9 a can be rotated relative to each other, and by holding the suspension connection portion 10 provided at the upper end of the inner shaft body 9 a of the swivel mechanism 9 in a fixed state, Since the series of members 2, 3, 4 and 6 of the cylindrical base frame 2, the shell mounting frame 3, the shell 4 and the lifting frame 6 are free of rotation, it is parallel to the rotary excavation of the casing in the cast-in-place pile method and other foundation works Then excavation and earth removal work inside the casing Even when the shell 4 or the shell mounting frame 3 comes into contact with the rotating casing C when the cut or crushed ready-made pile is picked up, the cylindrical base frame 2, the shell mounting frame 3, the shell 4 and the lifting and lowering are performed. By simply rotating the series of members of the frame 6 together, the suspension connection portion 10 is held in a non-rotating state, and there is no possibility that the hydraulic piping tube, power cable, wire, or the like is twisted and damaged.

  According to the invention of claim 2, a series of members 2, 3, 4, 6, 29 comprising the cylindrical base frame 2, the shell mounting frame 3, the shell 4, the elevating frame 6 and the stabilizer 29, and the cylindrical base frame 2 is a series of other members including a shell opening / closing drive cylinder 5 disposed in the cylinder 2, a connecting rod 8 connected to the lower end side of the cylinder 5, and an inner shaft body 9a of the swivel mechanism 9 connected to the upper end side of the cylinder 5. 5, 8, 9 a can rotate relative to each other, so that when the existing pile buried in the ground is pulled out, the upper end of the existing pile is grasped by the shells 4, 4 and the inside of the casing C penetrated The pusher 28 of the stabilizer 29 is brought into pressure contact with the peripheral surface, and the cylindrical base frame 2 is integrated with the casing C, and the casing C is rotated and pulled out by the all-round rotation driving device, thereby being gripped by the shells 4 and 4. The existing pile It can be pulled out in easily.

  If a plurality of sheaves 26 are juxtaposed to the suspension connection portion 10 and the suspension wires 27 are hung on these sheaves 26 as in the invention according to claim 3, the suspension is thereby suspended. Since the rotation of the connecting portion 10 can be prevented, no special rotation preventing means is required, and the equipment is simplified.

  According to the fourth aspect of the present invention, the cylindrical base frame 2, the shell mounting frame 3, the shell 4, the shell opening / closing drive hydraulic cylinder 5, the lifting frame 6, and the inner shaft body 9 a of the swivel mechanism 9 are integrally formed. The series of members 2, 3, 4, 5, 6, 9 a and the outer cylinder body 9 b of the swivel mechanism 9 are rotatable relative to each other and are integrated with the outer cylinder body 9 b of the swivel mechanism 9. By holding the suspension connection portion 10 provided in the fixed state, the series of members 2, 3, 4, 5, 6, and 9a are free to rotate. Therefore, the casing is rotated in the cast-in-place pile method or other foundation work. Even when the shell 4 or the shell mounting frame 3 contacts the rotating casing C when performing excavation and earthing work inside the casing in parallel with excavation or gripping work such as a ready-made pile cut or crushed in the middle, A cylindrical base frame 2 and a shell mounting frame 3; A series of members 2, 3, 4, 5, 6, 9a consisting of the pressure cylinder 5, the lifting frame 6, and the inner shaft body 9a of the swivel mechanism 9 rotate together, and the suspension connection portion 10 is held in a non-rotating state. Therefore, there is no possibility that the suspension wire 27, the hydraulic piping tube, the power cable, and other wires are twisted and damaged.

  As in the invention according to claim 5, the cylindrical base frame 2, the shell mounting frame 3, the shell 4, the shell opening / closing driving hydraulic cylinder 5, the lifting frame 6, the inner shaft body 9a of the swivel mechanism 9, and the stabilizer 49 are mutually connected. The series of members 2, 3, 4, 5, 6, 9a, 29 and the outer cylinder 9b of the swivel mechanism 9 are rotatable relative to each other, and the outer cylinder of the swivel mechanism 9 is connected. By holding the suspended connection part 10 provided integrally with the body 9b in a fixed state, the series of members 2,3,4,5,6,9a, 29 are free to rotate, so that they are buried in the ground. When the existing pile is pulled out, the upper end of the existing pile is grasped by the shells 4 and 4, and the pusher 28 of the stabilizer 49 is pressed against the inner peripheral surface of the casing C penetrated into the ground. The base frame 2 is integrated with the casing C. In state, by pulling while rotating the casing C by the entire circumference rotary drive, it may draw existing pile grabbed the shell 4,4 ground f easily.

  According to the invention of claim 6, if a plurality of sheaves 26 are arranged in parallel on the suspension connection portion 10 and the suspension wires 27 are hung on these sheaves 26, the suspension is thereby suspended. Since the rotation of the connecting portion 10 can be prevented, no special rotation preventing means is required, and the equipment is simplified.

  Embodiments of the present invention will be described below with reference to the drawings. First, (a) of FIG. 1 is a longitudinal sectional view showing the entire hammer grab 1 according to the present invention, and (b) is a hanging connection of the hammer grab 1. FIG. 2 is an enlarged view of the upper part of the hammer grab 1, and FIG. 3 is an enlarged view of the lower part.

  The hammer grab 1 has a shell mounting frame 3 fixed to a lower end portion of a cylindrical base frame 2, and a pair of shells 4 and 4 are pivotally attached to the shell mounting frame 3. The drive hydraulic cylinder 5 is concentrically arranged, and the lifting frame 6 is attached to the lower part of the cylindrical base frame 2 so that it can only be lifted and lowered, and concentric with the bearing 7 in the lifting frame 6 only for relative rotation. The connecting rod 8, which is attached to the hydraulic cylinder 5, is integrally connected to the piston rod 5 b of the hydraulic cylinder 5. The cylinder body 5 a of the hydraulic cylinder 5 has an inner shaft body 9 a and an outer cylinder that is externally fitted so as to be rotatable only. The inner shaft body 9a of the swivel mechanism 9 composed of the body 9b is concentrically connected, and the outer cylinder body 9b is fixed to the cylindrical base frame 2 side, and is suspended from the upper end side of the inner shaft body 9a. And the elevating frame 6 and the shell 4 are linked and linked by the link mechanism 12 It is obtained by so as to open and close the shell 4 by the lifting of the elevator frame 6 Thus due to the expansion and contraction operation of the hydraulic cylinder 5.

  The structure of the hammer grab 1 will be described in more detail. The cylindrical base frame 2 includes a cylindrical main body 2a having flanges a and b at both upper and lower ends, and an outer peripheral surface of the cylindrical main body 2a at regular intervals in the circumferential direction. The reinforcing rib 2b is disposed. The elevating frame 6 disposed at the lower part of the cylindrical base frame 2 in the cylindrical main body 2a has a predetermined stroke from the lower limit position indicated by the solid line in FIG. As shown in FIG. 3, it is composed of an inner cylinder member 6a, an outer cylinder member 6b, and a connecting member 6c that connects both members 6a and 6b. As shown in FIG. 3, the outer periphery of the outer cylinder member 6b is omitted. A convex strip extending in the axial direction is formed on one of the side and the inner peripheral side of the cylindrical main body 2a, and a concave strip that is slidably fitted to the convex strip is formed on the other side. The elevating frame 6 moves up and down along the cylindrical main body 2a of the cylindrical base frame 2 in a state where it can rotate integrally with the cylindrical base frame 2 by the concave-convex fitting between the strips and the convex strips. .

  As can be seen from FIG. 3, the connecting rod 8 is inserted into the inner cylinder member 6 a of the elevating frame 6 via the bearing 7 so as to be capable of relative rotation only. In FIG. 3, 52 and 53 show the upper and lower cover members fixed to the upper and lower ends of the inner cylinder member 6a.

  Further, as shown in FIG. 3, a pair of connecting rods 14, 14 are provided at both ends of the rod mounting member 13 that is integrally provided at the lower end portion of the inner cylinder member 6 a of the elevating frame 6 via the lower lid member 53. One end of each is pivotally attached by a pin 54. On the other hand, a pair of shells 4 and 4 are pivotally attached to the shell mounting frame 3 integrally attached and fixed to the lower end portion of the cylindrical base frame 2 by pins 55, and the swing levers of both shells 4 and 4 are connected. The leading ends of 4a and 4a and the other ends of the connecting rods 14 and 14 are pivotally connected by pins 56, respectively. The rod attachment member 13, the pair of connecting rods 14, 14, the swing levers 4 a, 4 a of both shells 4, 4 and the pins 54, 55, 56 constitute the link mechanism 12.

  Therefore, as shown in FIG. 1, when the piston rod 5b of the shell opening / closing hydraulic cylinder 5 is extended and the elevating frame 6 is in the lower limit position as shown by the solid line, both shells 4 and 4 are in the open posture. However, when the piston rod 5b of the hydraulic cylinder 5 contracts from this state and the elevating frame 6 rises from the lower limit position to the upper limit position shown in the phantom line, both shells 4, 4 are opened by the link mechanism 12. From the posture, it becomes a closed posture as illustrated in a virtual line.

  As can be seen from FIG. 2, the swivel mechanism 9 includes an inner shaft body 9 a and an outer cylinder body 9 b that is externally fitted to the inner shaft body 9 a through bearings 15 and 16 so as to allow only relative rotation. The lower end flange portion 17 of the inner shaft body 9a and the upper end flange portion 18 of the cylinder body 5a of the hydraulic cylinder 5 are joined by a bolt 19, so that the inner shaft body 9a is concentrically integrated with the upper end portion of the cylinder body 5a. It is connected to. The outer cylindrical body 9 b is fixed to the upper end portion of the cylindrical base frame 2 via a fixing bracket 20.

  On the inner shaft body 9a side of the swivel mechanism 9, supply and discharge oil ports 22 and 23 for supplying and discharging pressure oil to and from the cylinder body 5a of the hydraulic cylinder 5 are provided. The oil passages 24 and 25 provided in the inner shaft body 9a communicate with the oil supply / discharge port of the cylinder body 5a. Although not shown in the drawings, the oil supply / discharge ports 22 and 23 of the inner shaft body 9a are connected to a hydraulic pressure source via hydraulic piping tubes. The hanging connection portion 10 is composed of a horizontal base plate 10a fixed in a horizontal posture on the upper end of the inner shaft body 9a. Two sheaves 26, 26 are provided on both ends of the horizontal base plate 10a. A shaft 27 is attached to the sheaves 26 and 26. A suspension wire 27 is hung from a jib tip of a crane (not shown). Thus, by hanging the suspension wire 27 on the two sheaves 26, 26 arranged side by side on the horizontal base plate 10a of the suspension connection portion 10, the suspension connection portion 10 is suspended when the hammer grab 1 is suspended. Can be held in a fixed state.

  In the hammer grab 1 configured as described above, a series of members 2, 3, 4, 6 comprising a cylindrical base frame 2, a shell mounting frame 3, a shell 4 and a lifting frame 6, and a cylindrical base frame 2 is a series of shell opening / closing drive cylinders 5 arranged in 2, a connecting rod 8 connected to the lower end side of the cylinder 5, and an inner shaft body 9 a of a swivel mechanism 9 connected to the upper end side of the cylinder 5. Since the members 5, 8, 9a of the swivel mechanism 9 are relatively rotatable, the tubular base frame 2 and the shell mounting are secured by holding the suspension connection portion 10 provided at the upper end of the inner shaft body 9a of the swivel mechanism 9 in a fixed state. A series of members 2, 3, 4, and 6 including the frame 3, the shell 4, and the lifting frame 6 are free to rotate.

  In the cast-in-place pile method using the hammer grab 1, as in the case of using the conventional hammer grab H shown in FIG. 12, the casing C is driven into the ground while rotating the casing C using the all-around rotation drive device. The hammer grab 1 is suspended by a suspension wire 27 suspended from the tip of the jib of the crane, the shells 4 and 4 are lowered into the casing C with the open posture, and thrust into the earth and sand. Change to the closed position, scoop up the earth and sand, hold the earth and sand between the closed shells 4 and 4 and pull up the entire hammer grab 1 to open the shells 4 and 4 to open the earth and sand. Discharge. Even if the shell 4 and the shell mounting frame 3 come into contact with the rotating casing C in this process, a series of members of the cylindrical base frame 2, the shell mounting frame 3, the shell 4 and the lifting frame 6 rotate together. Therefore, since the suspension connection part 10 is held in a non-rotating state, there is no possibility that the hydraulic piping tube, the power cable, the suspension wire 27 and other wires are twisted and damaged.

  In this embodiment, two sheaves 26, 26 are juxtaposed on the suspension connection portion 10, and the hammer grab 1 is suspended by a suspension wire 27 that is hung on both sheaves 26, 26. The hammer grab 1 may be suspended using a kelly bar. However, as in this embodiment, if two sheaves 26, 26 are provided side by side on the suspension connection portion 10 and the suspension wires 27 are hung on both sheaves 26, 26, the suspension is thereby suspended. Since the rotation of the lower connection portion 10 can be prevented, no special rotation preventing means is required, and the equipment is simplified. In this embodiment, two sheaves 26, 26 are installed on the horizontal base plate 10a. However, two or more sheaves 26 may be installed.

  4A is a longitudinal sectional view showing the whole of another hammer grab 11 according to the present invention, FIG. 4B is a sectional view taken along the line XX of FIG. 4A, and FIG. FIG. The hammer grab 11 is almost the same as the hammer grab 1 described with reference to FIGS. 1 to 3, but can move forward and backward in the outward radial direction from the center side with respect to the inner peripheral surface of the casing C driven into the ground. The difference is that a stabilizer 29 having a plurality of pushers 28 for integrating the cylindrical base frame 2 with the casing C by being pressed against the inner peripheral surface of the casing C when moving forward is provided integrally with the cylindrical base frame 2. .

  The stabilizer 29 has a machine frame 30 provided with a peripheral wall 30 a having an outer diameter substantially the same as the outer diameter of the shell mounting frame 3 and the shell 4. As can be seen from FIGS. 4 (a) and 4 (b), a pair of pushers 28 and 28 are disposed in the machine frame 30 on the lower side and the upper side, respectively. For example, FIG. Referring to the left and right pushers 28 and 28 disposed on the left and right sides of the inner shaft body 9a of the swivel mechanism 9, the left and right slides can be moved forward and backward in the outward radial direction along the lower left and right guide frames 32 and 32, respectively. The left and right slide members 33, 33 are attached to the respective distal ends of the members 33, 33, and the hydraulic return type double cylinders 34, 34 disposed on both sides along the lower left and right guide frames 32, 32. 4 and the pushers 28, 28 disposed on both front and rear sides of the inner shaft body 9a with respect to FIG. 4 (b) are radially outward along the front and rear guide frames 35, 35, respectively. Front / rear slide member 3 The front and rear slide members 36 and 36 are attached to the front end portions of the front and rear guide frames 35 and 35 at the same time by return-type double hydraulic cylinders 37 and 37 disposed on both sides thereof. It is designed to be driven forward and backward.

  Thus, the four pushers 28, which are the combination of the two lower pushers 28, 28 and the two upper pushers 28, 28, are composed of two lower double return cylinders 34, 34 and two upper pushers. The double hydraulic cylinders 37 and 37 are simultaneously driven forward and backward in the outward radial direction, and at the time of the forward drive, they protrude from the four front and rear four openings 38 provided on the peripheral wall 30a of the machine frame 30, and are shown in FIG. As shown in the phantom line, the inner peripheral surface of the casing C is pressed into contact with the casing C, so that the cylindrical base frame 2 is integrated with the casing C via the machine frame 30. ... retracted inside and cuts the edge with the casing C.

  The swivel mechanism 9 of the hammer grab 11 is almost the same as the hammer grab 1 shown in FIGS. 1 to 3 except that the inner shaft body 9a protrudes upward from the outer cylinder body 9b. And the stabilizer 29 is provided concentrically so that the outer cylinder 9b of this swivel mechanism 9 which protruded long may be enclosed. That is, the outer cylindrical body 9 b of the swivel mechanism 9 is integrally fixed to the upper end portion of the cylindrical base frame 2 via the fixing bracket 39, and the machine frame 30 of the stabilizer 29 is integrated with the fixing bracket 39. Accordingly, the machine frame 30 of the stabilizer 29 is integrally attached and fixed to the cylindrical base frame 2.

  Further, as shown in FIG. 5, at the upper end portion of the inner shaft body 9a of the swivel mechanism 9, there are supply / discharge oil ports 22 and 23 for supplying and discharging pressure oil to / from the cylinder body 5a of the shell opening / closing hydraulic cylinder 5. These oil supply / discharge ports 22 and 23 communicate with oil passages 24 and 25 provided in the inner shaft 9a, and these oil passages 24 and 25 are connected to the oil supply / discharge ports of the cylinder body 5a, respectively. ing. The upper end portion of the inner shaft body 9a is provided with a supply / discharge oil port 40 (only one supply / discharge oil port is shown) for supplying and discharging pressure oil to and from the pusher drive hydraulic cylinders 34 and 37 of the stabilizer 29. The oil supply and discharge ports 40 are connected to the hydraulic cylinders 34 and 37 of the stabilizer 29 from the branch ports 42 and 43 through hydraulic passages 41 and hydraulic piping tubes (not shown), respectively.

  According to the hammer grab 11 having the stabilizer 29 as described above, a series of members 2, 3, 4, 6, 29 comprising the cylindrical base frame 2, the shell mounting frame 3, the shell 4, the elevating frame 6, and the stabilizer 29 are provided. And a shell opening / closing driving cylinder 5 arranged in the cylindrical base frame 2, a connecting rod 8 connected to the lower end side of the cylinder 5, and an inner shaft body 9 a of the swivel mechanism 9 connected to the upper end side of the cylinder 5. Since the other series of members 5, 8, 9 a can be rotated relative to each other, when pulling out an existing pile embedded in the ground, the upper end of the existing pile is grasped by the shells 4, 4, As shown in FIG. 4 (b), the pusher 28 of the stabilizer 29 is brought into pressure contact with the inner peripheral surface of the penetrated casing C, and the cylindrical base frame 2 is integrated with the casing C. Turn casing C By pulling out while rolling, the existing piles grasped by the shells 4 and 4 can be easily pulled out. The pulling force of the casing C in this case is several times that of the case where the hammer grab 11 is lifted with a wire and pulled out, and is extremely strong.

  FIG. 6 is a longitudinal sectional view showing the entirety of still another hammer grab 21 according to the present invention. FIG. 7A is a side view of the upper end portion of the hammer grab 21 and FIG. FIG. FIG. 8 is an enlarged cross-sectional view of the swivel mechanism 9 portion of the hammer grab 21.

  The hammer grab 21 fixes the shell mounting frame 3 to the lower end portion of the cylindrical base frame 2, and a pair of shells 4, 4 are pivotally attached to the shell mounting frame 3, and the shell opening / closing drive is provided in the cylindrical base frame 2. The cylinder 5 is arranged concentrically, and an elevating frame 6 is provided at the lower part of the cylindrical base frame 2 so as to be movable up and down. The elevating frame 6 is concentrically connected to the piston rod 5b of the cylinder 5 to An inner shaft body 9a of a swivel mechanism 9 comprising an inner shaft body 9a and an outer cylinder body 9b rotatably fitted on the inner shaft body 9a is concentrically connected to the cylinder body 5a, and the cylinder 5 The cylinder main body 5a is fixed to the cylindrical base frame 2 side, the suspension connecting portion 10 is provided on the outer cylindrical body 9b of the swivel mechanism 9, and the elevating frame 6 and the shells 4 and 4 are interlocked and connected by the link mechanism 12. By raising and lowering the lifting frame 6 by the expansion and contraction operation of the cylinder 5 Those made as to open and close the shell 4,4 Te.

  The cylindrical base frame 2 has the same structure as that of the hammer grabs 1 and 11 described above, and the elevating frame 6 disposed at the lower part in the cylindrical main body 2 a of the cylindrical base frame 2 is provided with the hydraulic cylinder 5. A predetermined stroke is raised and lowered by an expansion / contraction operation, and is composed of a cylindrical member as schematically shown in FIG. 6, and although not shown, the outer peripheral side of the cylindrical lifting frame 6 and the cylinder of the cylindrical base frame 2 A convex strip extending in the axial direction is formed on one of the inner peripheral sides of the main body 2a, and a concave strip that is slidably fitted to the convex strip is formed on the other side. Due to the concavo-convex fitting with the ridges, the elevating frame 6 moves up and down along the cylindrical main body 2a of the cylindrical base frame 2 in a state where it can rotate integrally with the cylindrical base frame 2.

  A rod mounting member 13 is integrally provided at the lower end of the lifting frame 6, and one end of each of the pair of connecting rods 14, 14 is pivotally attached to both ends of the rod mounting member 13. Similarly to the hammer grabs 1, 11, a pair of shells 4, 4 are pivotally attached to the shell mounting frame 3 that is integrally attached to the lower end portion of the cylindrical base frame 2. , 4 are respectively pivotally attached to the leading ends of the swing levers 4a, 4a and the other ends of the connecting rods 14, 14. As shown in FIG. 6, when the piston rod 5b of the hydraulic cylinder 5 for opening and closing the shell is extended and the elevating frame 6 is at the lower limit position as shown by the solid line, both the shells 4 and 4 are in the open posture, When the piston rod 5b of the hydraulic cylinder 5 contracts from this state and the elevating frame 6 rises from the lower limit position to the upper limit position (not shown), the shells 4 and 4 are changed from the open position to the closed position by the link mechanism 12.

  As can be seen from FIG. 8, the swivel mechanism 9 includes an inner shaft body 9a coaxially and integrally connected to the upper end side of the cylinder body 5a of the hydraulic cylinder 5, and bearings 15 and 16 connected to the inner shaft body 9a. The outer ring body 9b is externally fitted so that only relative rotation is possible, and the outer ring body 9b is fixed to the outer ring body 9b in a concentrically externally fitted state. At the same time, a plurality of support pieces 10b are suspended from the lower surface side of the mounting ring 10a, and are fixed to the outer peripheral surface of the outer cylindrical body 9b at regular intervals in the circumferential direction. Two sheaves 26, 26 are juxtaposed, and a suspension wire 27 is hung on both sheaves 26, 26. 6-8, 44 shows the upper end support frame of the cylindrical base frame 2. As shown in FIG.

  As shown in FIG. 8, the outer cylinder 9b of the swivel mechanism 9 is provided with supply / discharge oil ports 45 and 46 for supplying and discharging pressure oil to / from the cylinder body 5a of the hydraulic cylinder 5, and these supply / discharge oil ports 45 and 46 communicate with oil passages 47 and 48 provided in the inner shaft body 9a of the swivel mechanism 9, respectively. These oil passages 47 and 48 are cylinders for opening and closing the shell through a hydraulic pipe tube (not shown). 5 is connected to the oil supply / discharge port.

  According to the hammer grab 21 configured as described above, the cylindrical base frame 2, the shell mounting frame 3, the shell 4, the shell opening / closing driving hydraulic cylinder 5, the lifting frame 6, and the inner shaft body 9a of the swivel mechanism 9 are provided. Since the series of members 2, 3, 4, 5, 6, 9a and the outer cylinder body 9b of the swivel mechanism 9 are relatively rotatable with each other, the outer cylinder body of the swivel mechanism 9 is connected. By holding the suspended connection portion 10 provided integrally with 9b in a fixed state, the series of members 2, 3, 4, 5, 6, and 9a are free to rotate.

  In the cast-in-place pile method using the hammer grab 21, the casing C is driven into the ground while rotating the casing C by using an all-around rotation drive device, and the hammer grab is suspended by a suspension wire 27 suspended from a jib tip of a crane (not shown). 1 was suspended and lowered into the casing C with the shells 4 and 4 in the open posture, and pushed into the earth and sand. Then, the shells 4 and 4 were changed to the closed posture and the earth and sand were scooped and closed. With the earth and sand held between the shells 4 and 4, the entire hammer grab 1 is pulled up, and the shells 4 and 4 are opened on the ground to discharge the earth and sand. Even if the shell 4 and the shell mounting frame 3 come into contact with the rotating casing C in this process, the cylindrical base frame 2, the shell mounting frame 3, the shell 4, the shell opening / closing drive hydraulic cylinder 5, and the lifting frame 6 are used. And a series of members 2, 3, 4, 5, 6 and 9a comprising the swivel mechanism 9 and the inner shaft body 9a rotate together, so that the suspension connecting portion 10 is held in a non-rotating state. There is no fear that the wire 27, the hydraulic piping tube, the power cable, and other wires will be twisted and damaged.

  9 is a longitudinal sectional view showing the whole of another hammer grab 31 according to the present invention, FIG. 10 (a) is a side view of the upper side of the hammer grab 31, and FIG. 9 (b) is a YY line in FIG. FIG. 11 is a partially enlarged view of FIG. 9. The hammer grab 31 shown here is almost the same as the hammer grab 21 described with reference to FIGS. 6 to 8, but advances and retreats in the outward radial direction from the center side with respect to the inner peripheral surface of the casing C driven into the ground. A stabilizer 49 having a plurality of pushers 28 that are movable and are pressed against the inner peripheral surface of the casing C when moving forward to integrate the cylindrical base frame 2 with the casing C is provided integrally with the cylindrical base frame 2. Is different.

  The stabilizer 49 is similar to the stabilizer 29 of the hammer grab 11 described with reference to FIGS. 4 and 5, and includes a machine frame 50 including a peripheral wall 30 a having an outer diameter substantially the same as the outer diameter of the shell mounting frame 3 and the shell 4. Have As can be seen from FIGS. 9 and 10, a pair of pushers 28, 28 are disposed on the lower stage side and the upper stage side in the machine casing 50, and the two lower pushers 28, 28 are arranged in the diametrical direction. Are attached to the tip ends of the slide members 33 and 33 on both ends of the lower guide frame 32 provided along the slide guide 33, and are provided between the slide members 33 and 33. The two upper pushers 28 and 28 are simultaneously moved forward and backward by the slide members 36 and 36 on both ends of the upper guide frame 35 provided in the diametrical direction so as to be orthogonal to the lower guide frame 32. It is attached to the tip and is driven forward and backward simultaneously by a return double hydraulic cylinder 37 interposed between the slide members 36 and 36.

  Thus, the four pushers 28, which are the two lower pushers 28, 28 and the upper two pushers 28, 28, are composed of a lower return double hydraulic cylinder 34 and an upper return double hydraulic cylinder 34. 37 are simultaneously driven forward and backward in the outward radial direction, and projecting from the front, rear, left and right four openings 38 provided on the peripheral wall 50a of the machine frame 50 at the time of the forward drive, FIG. 9, FIG. 10 (a), FIG. As shown in the phantom line, the inner peripheral surface of the casing C is pressed into contact with the casing C, thereby integrating the cylindrical base frame 2 with the casing C via the machine frame 50, and the opening 38 of the cylindrical base frame 2 is retracted. ... retracted inside and cuts the edge with the casing C.

  The stabilizer 49 attaches and fixes the machine frame 50 to the upper end portion of the cylindrical base frame 2 concentrically with the cylindrical base frame 2 via the attachment frame 59. An inner shaft body 9 a of the mechanism 9 is erected and fixed concentrically with the cylindrical base frame 2.

  The swivel mechanism 9 of the hammer grab 31 is integrally connected coaxially to the upper end side of the cylinder body 5a of the hydraulic cylinder 5 via a stabilizer 49, like the hammer grab 21 described in FIGS. An inner shaft body 9a and an outer cylinder body 9b externally fitted to the inner shaft body 9a via bearings 15 and 16 so as to allow only relative rotation are provided, and a suspended connection portion 10 is provided on the outer cylinder body 9b. Therefore, the outer cylinder body 9b of the swivel mechanism 9 is provided with supply / discharge oil ports 45, 46 for supplying and discharging pressure oil to / from the cylinder body 5a of the shell opening / closing drive hydraulic cylinder 5. , 46 communicate with oil passages 47, 48 provided in the inner shaft body 9a, respectively, and these oil passages 47, 48 are connected to an oil supply / discharge port of the cylinder body 5a via an oil passage (not shown). Yes.

  In addition, the outer cylinder body 9b of the swivel mechanism 9 is provided with supply and discharge oil ports 57 and 58 for supplying and discharging pressure oil to and from the hydraulic cylinders 34 and 37 of the stabilizer 49. Although not shown, the oil passages are respectively connected to oil passages provided in the inner shaft body 9a, and these oil passages are connected to the respective oil supply and discharge ports of the hydraulic cylinders 34 and 37 through oil passage pipes. .

  According to the hammer grab 31 provided with the stabilizer 49 as described above, the cylindrical base frame 2, the shell mounting frame 3, the shell 4, the shell opening / closing drive hydraulic cylinder 5, the lifting frame 6, and the inner shaft body 9 a of the swivel mechanism 9. And the stabilizer 49 are integrally connected to each other, and the series of members 2, 3, 4, 5, 6, 9a, 29 and the outer cylindrical body 9b of the swivel mechanism 9 are relatively rotatable. By holding the suspension connection portion 10 provided integrally with the outer cylindrical body 9b of the swivel mechanism 9 in a fixed state, the series of members 2, 3, 4, 5, 6, 9a, and 29 are free to rotate. .

  Therefore, when pulling out an existing pile buried in the ground, the upper end of the existing pile is grasped by the shells 4 and 4 and the pusher of the stabilizer 49 is placed on the inner peripheral surface of the casing C penetrating into the ground. 28, with the cylindrical base frame 2 being integrated with the casing C, with the cylindrical base frame 2 being integrated with the casing C, the existing piles gripped by the shells 4 and 4 can be easily pulled to the ground by pulling out the casing C while rotating the casing C. Can be pulled out.

  In the embodiment described above, hydraulic cylinders are used as the shell opening / closing driving cylinder 5 and the pusher driving cylinders 34 and 37 of the stabilizers 29 and 49, respectively, but an air cylinder may be used instead of the hydraulic cylinder. .

(a) is a longitudinal sectional view showing the entirety of the hammer grab according to the present invention, and (b) is a plan view of a hanging connection part of the hammer grab. It is an enlarged view of the upper part side of the hammer grab shown in FIG. It is an enlarged view of the lower part side of the hammer grab shown in FIG. (a) is the longitudinal cross-sectional view which shows the whole other hammer grab based on this invention, (b) is XX sectional view taken on the line of (a). FIG. 5 is a partially enlarged view of FIG. It is a longitudinal cross-sectional view which shows the whole other hammer grab which concerns on this invention. (a) is a side view of the upper end portion of the hammer grab shown in FIG. 6, and (b) is a plan view of the upper end portion of the hammer grab. It is an expanded sectional view of the swivel mechanism part of the hammer grab shown in FIG. It is a longitudinal cross-sectional view which shows the whole other hammer grab which concerns on this invention. (a) is (a) a side view of the upper side of the hammer grab shown in FIG. 9, (b) is a cross-sectional view taken along line YY of FIG. FIG. 10 is a partially enlarged view of FIG. 9. It is explanatory drawing of the state which is excavating using the conventional hammer grab.

Explanation of symbols

C Casing 1 Hammer grab 2 Cylindrical base frame 3 Shell mounting frame 4 Shell 5 Shell opening / closing drive cylinder 6 Lifting frame 8 Connecting rod 9 Swivel mechanism 9a Inner shaft body 9b Outer cylinder body 10 Hanging connection portion 11 Hammer grab 12 Link Mechanism 21 Hammer grab 26 Sheave 28 Pusher 29 Stabilizer 27 Hanging wire 31 Hammer grab 49 Stabilizer

Claims (6)

  A shell mounting frame is fixed to the lower end portion of the cylindrical base frame, a plurality of shells are pivotally attached to the shell mounting frame, and a cylinder for opening and closing the shell is concentrically disposed in the cylindrical base frame, and is cylindrical. An elevating frame is provided in the lower part of the base frame so as to be movable up and down, and the lower end side of the cylinder is connected to a connecting rod that is concentrically mounted in the elevating frame via a bearing so as to be relatively rotatable. Is connected concentrically to the inner shaft body of a swivel mechanism comprising an inner shaft body and an outer cylinder body rotatably fitted on the inner shaft body, and the outer cylinder body is fixed to the cylindrical base frame side, A hammer grab provided with a hanging connection part on the upper end side of the shaft body, interlockingly connecting the elevating frame and the shell by a link mechanism, and opening and closing the shell by elevating the elevating frame by the expansion and contraction operation of the cylinder .   The cylindrical base frame can move forward and backward in the radial direction outward from the center side with respect to the inner peripheral surface of the casing that is driven into the ground, and is pressed against the inner peripheral surface of the casing when moving forward. The hammer grab according to claim 1, wherein a stabilizer having a pusher for integration is integrally provided.   The hammer grab according to claim 1 or 2, wherein a plurality of sheaves are arranged in parallel on the suspension connection portion, and suspension wires are hung on the sheaves.   A shell mounting frame is fixed to the lower end portion of the cylindrical base frame, a plurality of shells are pivotally attached to the shell mounting frame, and a cylinder for opening and closing the shell is concentrically disposed in the cylindrical base frame, and is cylindrical. An elevating frame is provided at the lower part of the base frame so as to be movable up and down, and the elevating frame is concentrically connected to the lower end side of the cylinder, and an outer shaft that is rotatably fitted to the inner shaft body on the upper end side of the cylinder. An inner shaft body of a swivel mechanism composed of a cylindrical body is concentrically connected, an upper end side of the cylinder is fixed to a cylindrical base frame side, a suspension connection portion is provided on an outer cylindrical body of the swivel mechanism, and the lifting frame A hammer grab in which the shell and the shell are interlocked and connected by a link mechanism, and the shell is opened and closed by raising and lowering the lifting frame by the expansion and contraction operation of the cylinder.   The cylindrical base frame can move forward and backward in the radial direction outward from the center side with respect to the inner peripheral surface of the casing that is driven into the ground, and is pressed against the inner peripheral surface of the casing when moving forward. The hammer grab according to claim 4, wherein a stabilizer having a pusher for integration is integrally provided.   The hammer grab according to claim 4 or 5, wherein a plurality of sheaves are arranged side by side on the suspension connection portion, and suspension wires are hung on the sheaves.

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