JP2001303878A - Weight type excavator and excavation method for ground - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a weight type excavator and a ground excavation method capable of efficiently performing excavation with simple facilities. SOLUTION: This excavator comprises a weight having a through hole, a hydraulic cylinder equipped with a suspension means for suspending the weight at the tip of a piston rod, a suspension frame for suspending the hydraulic cylinder equipped with the hydraulic cylinder for directing the tip of the piston rod downward at the upper inner side, and a suspension frame at the lower inner side which is equipped with a falling impact cushioning member, and the weight is suspended from the suspension means through a coupling member and the weight is interlocked with the movement of the piston rod and moves up and down thereby giving impacts to the ground for excavation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic cylinder driven type weight excavator and a method for excavating ground.

[0002]

2. Description of the Related Art Conventionally, a ground excavation method using a weight type excavator has been carried out by winding up a weight with a winch, free-falling, and crushing the ground to excavate. The method of excavating the ground by lifting a ram with a hydraulic cylinder and causing the ram to collide with the pile head and dropping a weight connected to the ram via a wire is described in Japanese Unexamined Utility Model Publication No.
No. 22525.

[0003]

The conventional weight excavator and the method of excavating the ground have the following problems. <B> The method of hoisting the weight with a winch requires large-scale equipment such as a three-point pile driver, a gantry, and a turret. <B> When a winch is used, it takes time to wind up. For this reason, the number of hits per unit time depends on the winch hoisting speed. <C> Heat loss of the winch stop brake after free fall of the weight, and loss time due to slackening of the wire occur. This loss time reduces the number of hits per unit time. <D> The method using a hydraulic cylinder and a ram presupposes that a steel pipe pile is driven as a pile. For this reason,
If the pile driving speed and the rock excavation speed are not synchronized, there is a restriction on the use such as adjustment is not possible.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a weight excavator capable of efficiently excavating with simple equipment and a method for excavating a ground. Aim.

[0005]

In order to achieve the above object, a weight type excavator according to the present invention comprises a weight having a through hole, and a weight for suspending the weight at the tip of a piston rod. A hydraulic cylinder with a suspending device, a suspension frame for suspending the hydraulic cylinder, the hydraulic cylinder is provided on the upper inner side such that the tip of the piston rod faces downward, and a drop impact buffer is provided on the lower inner side. And a suspension frame provided with the weight. The weight is suspended from the suspension via a connecting member, and the weight moves up and down in conjunction with the movement of the piston rod to strike and excavate the ground. Here, it is desirable that the distance between the lower surface of the suspender at the uppermost position and the upper surface of the drop impact buffer at the time of the minimum contraction be shorter than the maximum stroke of the piston rod. Further, in the method of excavating the ground, in the method of excavating the ground using the above-mentioned weight type excavator, the casing is vertically built on the ground to be excavated, the weight is inserted into the casing, and the through hole of the weight is inserted into the through hole of the weight. Insert the sediment discharge pipe, fix the lower end of the sediment discharge pipe so as not to contact the ground near the ground, lift the suspension frame attached with the hydraulic cylinder with a crane via a suspension shock absorbing material, and lift the suspension frame to the weight The weight of the weight is hung by connecting the attached connecting member to the hanger, and the position of the hydraulic cylinder is adjusted so that the lower end of the weight contacts the ground before the stroke of the piston rod is maximized. By adjusting the stroke length of the piston rod and operating the hydraulic cylinder, the ground is crushed and the generated sediment is discharged through a sediment discharge pipe.

[0006]

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

<A> Hydraulic Cylinder As the hydraulic cylinder 1, a known hydraulic cylinder used for a hydraulic hammer, for example, is used. The hydraulic cylinder 1 includes a piston rod 11 therein, and reciprocates the piston rod 11 by hydraulic pressure. At the tip of the piston rod 11, a suspending tool 32 for suspending the weight 3 is attached. The hanging member 32 is wider than the diameter of the piston rod 11, and for example, a rod-shaped member or a flange-shaped member having hanging holes at both ends can be used.

<B> Drop impact buffering material and hanging impact buffering material When the pulling force acts on the connecting members (33, 34), the drop impact buffering material 21 is used for the piston rod 1 via the suspending tool 32.
And for damping the shock transmitted to the hydraulic cylinder 1. For example, a coil spring, rubber, or the like can be used. Before the stroke of the piston rod 11 is maximized, the hanging member 32 collides with the drop impact buffer 21. As a result, even when the weight is suspended in the air without reaching the ground, a failure such as the piston rod 11 falling out of the hydraulic cylinder 1 does not occur. FIG. 2 is a diagram illustrating the positional relationship between the hanging tool and the drop impact buffer. The suspension shock buffering member 22 is for buffering a shock transmitted to the crane via the suspension frame 2 when a tensile force acts on the connecting members (33, 34). The same material as the drop impact buffer 21 can be used as the suspension impact buffer 22.

<C> Weight The weight 3 is a weight having a through hole 31 at the center. In addition to the through hole 31, a water passage hole 35 can be provided so that water injected into the casing can move up and down the weight 3. The weight 3 is, for example, a double pipe consisting of an inner pipe 37 and an outer pipe 36, in which a gap between the inner pipe and the outer pipe is partitioned by a plurality of plate members 38, and penetrates vertically through a central portion of a columnar steel material and the periphery thereof. FIG. 3 shows a sectional view of one embodiment of the weight.

Hereinafter, a method for excavating ground according to the present invention will be described with reference to the drawings.

<A> Installation of Casing and Installation of Weight-Type Excavator A casing 5 is installed vertically on the ground to be excavated. The erection is performed by pushing the tip of the casing 5 into the ground using a vibratory hammer, a rotary push-in type pile driver, or the like. Thereafter, the weight 3 is inserted into the casing 5. The earth and sand discharge pipe 4 is inserted into the through hole 31 of the weight 3. The earth and sand discharge pipe 4 is fixed at a position where the lower end does not contact the ground near the ground by hanging from above. Then, the suspension frame 2 to which the hydraulic cylinder 1 is attached is lifted by a crane via the suspension shock absorbing material 22. Hanging device 32 and weight 3 attached to the lower end of piston rod 11
Is connected by connecting members (33, 34) such as wires and chains.

<B> Excavation and discharge of earth and sand Once the piston rod 11 is extended, the lower end of the weight 3 is brought into contact with the ground. Then, the position of the suspension frame 2 is adjusted so that a predetermined slack occurs in the connecting members (33, 34). Thereafter, the hydraulic cylinder 1 is operated. As a result, the weight 3 falls and collides with the ground, and the ground is crushed. here,
By adjusting the stroke length of the piston rod, a falling stroke of the weight according to the rock mass strength can be obtained. The earth and sand 61 generated by crushing the ground is discharged by the earth and sand discharge pipe 4. As a discharging method, a known method such as an air lift method and a pump-up method can be used.

[0013]

According to the weight excavator and the method for excavating the ground of the present invention, the following effects can be obtained. <B> The hydraulic cylinder that lifts the weight is suspended and fixed by a crane. Therefore, equipment such as a tower required for a conventional special winch and a large gantry for setting a dedicated excavator is not required. As a result, the preparation period before construction can be shortened, and the labor and cost required for the preparation work can be reduced. <B> A crane suspension system is applicable. For this reason, fine adjustment of the excavation position is facilitated, and the construction speed is increased. <C> The lifting speed of the weight by the hydraulic cylinder is faster than when a winch is used. Therefore, the number of hits per unit time can be increased. As a result, the excavation efficiency also increases. <D> A drop impact buffer is provided so that the piston rod does not extend to the maximum stroke. Therefore, the hydraulic cylinder is less likely to break down. <E> The casing is not driven by the operation of the hydraulic cylinder. For this reason, the casing can be removed after excavation. That is, the present invention can be used as an auxiliary construction method when driving a pile into a boulder layer or a bedrock.

[Brief description of the drawings]

FIG. 1 is a sectional view of an embodiment of a weight-type excavator according to the present invention.

FIG. 2 is an explanatory view of an embodiment of a weight type excavator.

FIG. 3 is a cross-sectional view of the weight.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Hydraulic cylinder 11 ... Piston rod 2 ... Hanging frame 22 ... Hanging shock absorbing material 3 ... Weight 31 ... Through hole 32 ... Hanging tool 33 ... Connecting material 34 ... Connecting material 4 ... sediment discharge pipe 5 ... casing

Claims (2)

[Claims] 1. A weight having a through hole, a hydraulic cylinder having a hanging member for hanging the weight at the tip of a piston rod, and a suspension frame for suspending the hydraulic cylinder. A suspension frame provided with the hydraulic cylinder such that the tip of the rod faces downward, and a suspension frame provided with a drop impact buffer on the lower inside thereof, and the weight is suspended from the suspension by a connecting member. A weight-type excavator that strikes and excavates the ground by moving the weight in conjunction with the movement of the piston rod. 2. A method for excavating a ground using a weight type excavator according to claim 1, wherein a casing is erected vertically on the ground to be excavated, the weight is inserted into the casing, and a through hole of the weight is provided. And the lower end of the sediment discharge pipe is fixed so as not to contact the ground in the vicinity of the ground, and the suspension frame to which the hydraulic cylinder is attached is suspended by a crane via a suspension shock-absorbing material. Connect the connecting material attached to the suspension to the lifting device and suspend the weight, adjust the position of the hydraulic cylinder so that the lower end of the weight contacts the ground before the stroke of the piston rod is maximized, according to the rock strength Ground excavation method in which the ground is crushed by adjusting the stroke length of the piston rod and operating the hydraulic cylinder, and the generated sediment is discharged through a sediment discharge pipe.