JPS6357561B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a mandrel driving device.

[Prior Art] Generally, mandrels are made as thin as possible in order to reduce driving resistance and not to disturb the ground, and because their slenderness ratio is extremely large, there is a risk that they will buckle easily.

Conventionally, in order to solve this problem,
As disclosed in the above publication, there is a technique for preventing buckling by holding a mandrel in the middle with a buckling prevention plate so that it can be inserted freely.

[Problems to be Solved by the Invention] However, since the above-mentioned conventional buckling prevention plate does not have any restriction on its movement in the horizontal and lateral directions, there is a risk that the buckling prevention plate may move in the horizontal and lateral directions while the mandrel is bent. It was hot.

In addition, in the conventional device described above, since the horizontal movement of the frame that fixes the upper end of the mandrel is not restricted in any way, the mandrel cannot be moved laterally with the mandrel bent in the same way as the buckling prevention plate described above. In the end, it was not possible to completely prevent buckling of the mandrel.

The present invention has been made in order to solve the above-mentioned conventional problems, and its purpose is to provide a mandrel driving device that completely prevents buckling of the mandrel and allows smooth and safe driving. This is what I am trying to do.

[Means for Solving the Problems] The mandrel driving device of the present invention includes a driving device main body that is installed directly or indirectly on the ground into which a mandrel is to be driven, and a driving device main body that is installed on the ground into which a mandrel is to be driven. two guide columns erected in parallel with a predetermined interval, a top boom that integrally connects the upper ends of the two guide columns to form a gate-shaped rigid structure as a whole; A push-in beam is suspended from the top boom so as to be able to move up and down while being guided through guide rollers between the book guide columns, and a push-in beam whose upper end is fixed to the push-in beam is suspended in the ground as the push-in beam moves downward. The slender mandrel pushed into the mandrel is guided via a guide roller between the two guide columns, and is suspended from the push beam so as to be movable up and down so as to be positioned approximately midway between the push beam and the ground surface. and a buckling-preventing movable beam that holds the mandrel so that it can be inserted freely.

[Example] Hereinafter, an example of the present invention will be described with reference to the drawings.

In the figure, reference numeral 1 denotes a driving device main body, which is installed on the ground into which a mandrel is to be driven.

Two guide columns 2, 2 are erected in parallel on the driving device main body 1 with a predetermined interval maintained therebetween.

The upper ends of the guide columns 2, 2 are connected to the top boom 3.
The structure is integrally connected to form a gate-shaped rigid structure as a whole.

Reference numeral 4 denotes a mandrel which is elongated and prone to buckling, and its upper end is attached and fixed to the pushing beam 5.

The pushing beam 5 is suspended by a lifting wire 6 and is lowered by a pushing wire 7 to drive the mandrel 4 into the ground.

Reference numeral 8 denotes a buckling prevention movable beam, through which the mandrel 4 passes through an insertion hole 8a, and the driving beam 5 passes between the guide columns 2 while maintaining the spacing between the plurality of mandrels 4. It is designed to move up and down approximately halfway between the ground surface.

The above-mentioned push-in beam 5 and buckling prevention moving beam 8
Guide rollers 5a and 8 are provided at both ends of the
b is attached and makes contact with the inner surface of the guide column 2, so that each beam 5, 8 can be easily moved up and down. 9 is a drain drum.

Next, a description will be given of a mandrel driving operation using the apparatus of the above embodiment.

First, a drain material is set on the mandrel 4 while the mandrel 4 is lifted up by the lifting wire 6 as shown in the figure. Next, when the lifting wire 6 is loosened, the mandrel 4 descends under its own weight, and its lower tip pierces the ground surface. Subsequently, when the push wire 7 is pulled by an appropriate winch (not shown), the push beam 5 is pulled downward and the mandrel 4 is pushed into the ground against the driving resistance.

When the mandrel 4 is pushed into the ground and the pushing force increases, a buckling load acts on the mandrel 4.

In this embodiment, the upper end of the mandrel 4 is fixed to the push-in beam 5, and the lower part is inserted into the ground, so the part where buckling is likely to occur is located approximately in the middle of these two parts. The position where this is likely to occur moves as the driving stroke of the mandrel 4 progresses and the driving beam 5 descends. Therefore, if the movable beam 8 for buckling prevention is always positioned at an intermediate position between the push-in beam 5 and the ground surface and is moved by appropriate control means, the mandrel 4 can be prevented from buckling. You can always drive in a stable state without any problems.

When the driving of the mandrel 4 is completed, the pushing beam 5 is raised by the lifting wire 6 to pull out the mandrel 4, and at the same time the buckling prevention moving beam 8 is lifted.
is also pulled up to the initial intermediate position.

Although the above embodiment has been described with respect to mandrel driving on land, the present invention is not limited thereto and can also be used at sea, and any number of mandrels and driving means may be used.

[Effects of the invention] (1) A pushing beam for pushing the mandrel;
The buckling prevention movable beam, which penetrates and holds the middle part of the mandrel during pushing, is guided up and down by two guide columns.
Horizontal lateral movement of both beams is completely restricted, so there is no risk of the mandrel bending and buckling.

(2) The upper ends of the two guide columns are integrally connected by the top boom to form a gate-shaped rigid structure as a whole, so the two guide columns are reinforced and stabilized and the push beam and Not only can the above-mentioned horizontal lateral movement regulation of the buckling prevention movable beam be more stabilized, but also the push-in beam can be directly suspended by using the top boom, and the buckling prevention movable beam can also be suspended indirectly. Since both beams can be suspended, there is no need for a special structure for suspending both beams.

[Brief explanation of the drawing]

The figure is a front view showing one embodiment of the present invention. 1... Driving device main body, 2, 2... Guide column,
3... Top boom, 4... Mandrel, 5...
Pushing beam, 5a... Guide roller, 6... Lifting wire, 7... Pushing wire, 8... Moving beam for preventing buckling, 8a... Insertion hole, 8b... Guide roller, 9... Drain drum.

Claims (1)

[Claims] 1. A driving device body installed directly or indirectly on the ground where the mandrel is to be driven, and two guide columns erected parallel to the driving device body at a predetermined distance. , a top boom that integrally connects the upper ends of the two guide columns to form a gate-shaped rigid structure as a whole; and a top boom that is guided between the two guide columns via a guide roller. A push-in beam is suspended so as to be movable up and down, an elongated mandrel whose upper end is fixed to the push-in beam and is pushed into the ground as the push-in beam moves downward, and a guide between the two guide columns. a movable beam for buckling prevention that is suspended from the push-in beam so as to be movable up and down so as to be positioned approximately midway between the push-in beam and the ground surface while being guided through rollers, and holds the mandrel so that it can be inserted therethrough; A mandrel driving device comprising: