JPS58213919A - Pile drawer - Google Patents

Abstract

PURPOSE:To reduce shocks encountered when drawing out a pile by a method in which a vertically movable cylinder weight is acted on an arm having a chuck to grasp the weight receiver on its one end and a chuck to grasp a pile on its other end, and the pile is drawn out by moving the arm in a rocking manner. CONSTITUTION:A working liquid whose pressure is raised by a pump 17 enters from a port 19 into the upper chamber 2c of a weight 2, and thereby the weight 2 goes up along a guide pole 4. At this time, the buffer 12 side of the arm 8 is lifted up by a spring 15, the chuck 13 side is lowered, and a pile is clutched by claws facing each other. when switching a switch valve 18, the working liquid in the upper chamber 2c of the weight 2 is led to a tank 30, and the weight 2 goes down under its own weight. When the weight 2 drops to strike the buffer 12, the striking force acts as a drawing force on the chuck 13 at the supporting shaft 10 as a supporting point.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a pile extractor that uses hydraulic pressure to pull out piles by constant impact force.

As described in British Patent No. 826.490, conventional percussion type pile extractors convert the force raised from below using fluid pressure into pile extraction force against the weight of the ram. The disadvantage is that there is a lot of energy loss because the pile removal force is subtracted by the ram's own weight. In addition, in conventional pile extraction, the main body of the pile extraction machine is held by an auxiliary crane (1), which causes a shock to the auxiliary crane when pulling out by impact, and the upper end of the pile to be extracted must be clamped. Since this method uses an auxiliary crane to lift the pile, it has the disadvantage that as the pile becomes longer, a larger crane with a longer boom is required. Furthermore, since a gas such as steam is used as the working fluid, there is a drawback that the exhaust noise is loud.

SUMMARY OF THE INVENTION In view of the above-mentioned drawbacks, the present invention aims to provide a pile extractor that has low energy loss, does not require a large auxiliary crane, does not apply shock to the auxiliary crane during extraction, and produces less noise during work. .

In order to achieve this purpose, the pile extractor of the present invention includes a stationary main body that is placed on the ground into which the piles are driven, and a plurality of pipes that are movable up and down in the main body to supply working fluid. A cylindrical weight that rises and falls while discharging working fluid, and is swingably attached to a support shaft provided on the main body, with a receiving part for the weight at one end and a stake at the other end. and an arm provided with a chuck for grasping, and when the weight falls, the weight falling energy is applied to the receiving part of the arm, so that the arm swings and the pile grasped by the chuck at the other end of the arm is pulled out. It is characterized by being configured as follows.

An embodiment of the present invention will be described below with reference to the drawings.

Reference numeral 1 denotes the main body of a pile extractor, which is placed on the ground into which piles have been driven as shown in a of FIGS. 1 and 2. The main body 1 includes a base 21, left and right front pillars 4.4, left and right rear pillars 3,
3 are erected, an upper frame 22 is fixed to the top of these pillars, and a hanging ring 20 on the 2nd side of the main body is provided on the upper frame.

Reference numeral 2 denotes a cylindrical weight, in which a piston 5 integrated with a piston rod 6 is housed so as to be vertically movable, and guide shoes 2a, 2a protruding left and right have a U-shaped cross section and are formed into guide grooves. The upper end of the piston rod 6 is fitted into a bracket 23 fixed to the upper frame 22 with a pin 7.
are connected by.

At the top of the weight 2 is a boat 19 for supplying and discharging working fluids such as oil.
A high pressure generation pump 17 is connected to the boat 19 via a switching valve 18. Also,
An air inlet/outlet 2e is provided at the bottom of the weight 2. This air inlet/outlet 2e may be connected to a tank or an achievator.

Reference numeral 8 denotes an arm that is swingably attached by fitting an elongated hole 11 into a support shaft 10 provided on the main body 1, one end of which is located below the weight 2, and a weight receiving portion on the upper surface. A buffer material 12 forming a section is attached, and a U-shaped frame 9 is provided at the other end, and a chuck 13 for gripping the stake is attached to the frame 9.

The chuck 13 has a pair of left and right components that are symmetrical, and as shown in FIGS. 3 and 4, each of the left and right components includes a first gripper 24 and a second Kotta 25
, the claw 26 and the bearing 27 are removed. The first kettle 24 includes a round shaft 24a that is rotatably fitted into a round hole 28 provided in the frame 9, a second cock holding groove 24b provided vertically in the front and rear parts, and an inclined surface with a protruding lower part. 24c
and has. The second cotter 25 has a shoe 25a that fits into the holding groove 24b with some play at the front and rear, an inclined surface 25b that contacts the inclined surface 24c, and a second cotter 25 and a first cotter 24. It has a weight 25c integrally provided at the bottom to keep the handle in a constant direction at all times. The pawl 26 is rotatably attached to the second cock 25 via a bearing 27.

14 is a cushioning material placed on the base 21 in order to reduce the impact when one end of the arm 8 collides with the base 21 when the weight 2 falls, and also to limit the amount of swing of the arm 8; A spring 15 is attached between the rear columns 3, 3 of the main body 1 and the arm 8, and pushes down the chuck 13 by pushing up the opposite side of the chuck 13 and swinging the arm 8 when the weight 2 rises; Reference numeral 16 denotes a stopper installed between the left and right rear pillars 3.3 to limit the amount of descent of the arm 8 on the chuck 13 side.

Next, the operation of this device will be explained. First, hang the main body 1 on the hook of an auxiliary crane or the like on the crossbar 20, and set it so that the chuck 13 is positioned above the pile b (the illustrated example is a sheet pile) to be pulled out. Next, selector valve 1
8, the working fluid pressurized by the pump 17 enters the chamber 2c above the piston 5 of the weight 2 from the boat 19, and enters the air chamber 2 below the piston 5.
While pushing out the air d from the air inlet/outlet 2e, the weight 2 rises along the front pillars 4, 4 which act as guides. At this time, since the shock absorbing material 12 side of the arm 8 is pulled up by the spring 15, the chuck 13 side is lowered and the pile is held between the opposing claws 26 and 26. While the chuck 13 side is being lowered, a force is applied to the inclined surface 25b of the second saw blade 25 in a direction away from the inclined surface 24c of the first cock 24, so that the pile can be clamped. Next, when the switching valve 18 is switched to the right position, the working fluid in the chamber 2C of the weight 2 is communicated to the tank 30, and the weight 2 falls due to its own weight. When the weight 2 falls and hits the cushioning material 12, the impact force is applied to the arm 8 and the frame 9 using the support shaft 10 as a fulcrum.
A pulling force F (see FIG. 3) acts on the chuck 13 through the pull-out force F (see FIG. 3). At this time, the first cotter 24 and the second cotter 2
5 is in contact with the inclined surfaces 24c and 25b, and since gravity & is applied to the second cotter 25 by the weight 25c, a force P is generated that pushes the pawl 26 in the direction of the stake, and the stake is removed. It is pulled out by a predetermined distance while firmly gripping it. Next, by switching the switching pulp 18 to the 5th position again as described above, the chuck 13 side has the claws 26 on both sides of the pile.
While touching, descend and grab the lower part of the place you grabbed last time. The pile is pulled out by repeating these operations. It should be noted that the pull-out reaction force generated when the weight 2 is dropped and the pile sill is pulled out acts on the pile a next to the pile sill through the main body 1.

In this embodiment, the force of the spring 15 causes the chuck 1 to be
We created a force to push down the 3rd side, but the weight 2
The spring 15 may be eliminated by making 5c heavier.

As described above, the pile extractor of the present invention converts the energy of the free fall of the weight into pile extracting force, so that a large extracting force can be obtained with a small machine. Further, since the pile extractor of the present invention is a stationary type, an auxiliary crane is used when moving the pile, but since it is used separately from the main body when pulling out, no shock is applied to the auxiliary crane. The pile extractor of the present invention still has the following features:
Since the middle part of the pile is clamped instead of the upper end of the pile, the minimum crane needed to hang the main body or the pile is sufficient, and a long or large crane is not required. Still, since the present invention uses a hydraulic cylinder as the means for lifting the weight, noise is reduced.

[Brief explanation of the drawing]

Fig. 1 is a plan sectional view showing an embodiment of the pile extractor according to the present invention, Fig. 2 is a sectional view from the entrance side of Fig. 1, Fig. 3 is a BB sectional view of Fig. 1, and Fig. 4 is a sectional view of the pile extractor according to the present invention. FIG. 4 is a sectional view taken along line CC in FIG. 3; ]...Main body, 2 weights, 8 arms, 13 chucks Patent applicant Hitachi Construction Machinery Co., Ltd. Agent Patent attorney Tadashi Akimoto Actual agent Patent attorney Waka 1) Masaru -

Claims (1)

[Claims] A stationary main body, a cylindrical weight that can be freely attached to the main body up and down, rises when working fluid is supplied, and falls when working fluid is discharged, and a cylindrical weight that swings on a support shaft provided on the main body. an arm that is movably attached and has a receiving part for the weight at one end and a chuck for gripping the pile at the other end, and when the weight falls, weight falling energy is applied to the receiving part of the arm, A pile extractor characterized in that an arm swings to pull out a pile gripped by a chuck at the other end of the arm.