JP2507556Y2 - Drilling rig - Google Patents

Description

[Detailed Description of the Invention] <Industrial field of application> The present invention relates to a clamshell type excavating device for excavating the ground by picking up earth and sand with a pair of openable and closable buckets.

<Prior Art> Conventionally, as a ground excavation device, it is known that a pair of openable and closable buckets pick up earth and sand for excavation, which is called a clamshell type. It is already publicly known as seen in publications such as No. That is, the description will be made with reference to FIG. 1 (a side view of the excavator) showing an embodiment of the present invention. In the clamshell excavator, the buckets 1 and 1 facing each other are paired. Each of them is rotated around its pivot shaft 12 by the hydraulic cylinders 3, 3 to be opened and closed, and when excavating a pile hole or the like, this is properly adjusted with the teeth of both buckets 1, 1 opened downward. Drop it from the height and let the tooth tip bite into the ground,
After that, by driving the hydraulic cylinders 3 and 3, the buckets 1 and 1 are strongly tightened, the earth and sand are grabbed, and the bucket is lifted as it is.

<Problems to be solved by the invention> By the way, when the bucket 1 is rotated around its pivot 12, the driving force for rotation is always tangential to the rotation locus of the bucket 1 considering the dispersion of the force. It is advantageous to act in the direction that becomes a large moment is obtained. However, the driving force acts on the connecting shaft 13 that connects the rod 30 of the hydraulic cylinder 3, and the other end of the hydraulic cylinder 3 is above the connecting shaft 13 as the point of action and on the pivot shaft 12 of the bucket 1.
Since it is arranged so as to be pivoted substantially vertically above, the action direction of the driving force is not always the above-mentioned tangential direction, and there is a disadvantage that the driving force is dispersed, and the moment fluctuates.

In particular, when the bucket 1 is in the open state, the connecting shaft 13 is above the pivot shaft 12 and the hydraulic cylinder 3 is substantially vertically erected, so that the displacement in the working direction is large (the moment is small). There is a problem that the tightening force of both buckets 1 and 1 becomes small in the initial stage of the closing operation from the open state, which originally requires the largest force when excavating the etc. However, even if the driving force is excessively increased, the displacement in the operating direction is large when the bucket 1 is in the open state, so the effective tightening force is not all but part of it, resulting in poor efficiency and equipment cost. There was a problem because I was angry.

The present invention has been made in view of the background as described above, and provides a drilling device capable of strongly closing and rotating an opened bucket and increasing the tightening force in the initial stage of the closing operation from the opened state. Is its purpose.

<Means for Solving the Problem> In order to achieve the above object, the present invention is a so-called clamshell in which opposed buckets are rotated around a pivot by driving means such as a hydraulic cylinder to be opened and closed. It is characterized by comprising auxiliary drive means for driving the bucket in the open state from a substantially horizontal direction so that the resultant force of the bucket with the drive means is in a substantially tangential direction to the rotation locus.

<< Operation >> With the above configuration, the auxiliary drive means is driven at the same time when the bucket in the open state is started to be closed. As a result, a driving force is applied to the bucket from a direction substantially tangential to the rotation locus, and the acting directions are substantially the same, so that the tightening force is increased.

<< Embodiment >> An embodiment of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a side view showing a preferred embodiment of the excavating device according to the present invention, in which a part of the device is cut away.

This excavator is basically of a so-called clamshell type that excavates the ground by picking up earth and sand with a pair of openable and closable buckets. That is, the grab frame 2 with the two buckets 1 and 1 facing each other is paired.
A hydraulic cylinder that is rotatably supported by the glove frame 2 and that serves as drive means between the grab frame 2 and both buckets 1 and 1.
Buckets 1,3 made up of 3 and 3 facing each other
Are rotated around their pivot shafts 12 and 12 by the driving of the hydraulic cylinders 3 and 3, respectively, and are opened and closed. Further, the grab frame 2 is fixed to the lower end of a Kelly bar or the like (not shown) and can be vertically moved freely.

A hydraulic cylinder 4 is provided below the grab frame 2 as an auxiliary drive means for driving the bucket 1 in the open state. The hydraulic cylinder 4 is provided for each bucket 1, and the grab frame 2 has the bucket 1
Is installed above the pivot shaft 12, but at this time, the tip of the rod 40 is brought into contact with the connecting portion 13 of the bucket 1 in the open state, and the other end is rotatably supported by the grab frame 2. Moreover, the main body is suspended by the spring 5 and held in a substantially horizontal state. That is, although the hydraulic cylinder 4 is installed in the grab frame 2 in a substantially horizontal state, the spring 5 holds the hydraulic cylinder 4 so that the hydraulic cylinder 4 can swing about the pivot shaft 42.

Here, if the rod 40 of the hydraulic cylinder 4 is extended, the abutting connecting portion 13 is pressed, so that the bucket 1 is rotated around its pivot shaft 12, and the closing operation is performed. Become a drive. At this time, since the extension of the rod 40 is performed in a substantially horizontal direction, the bucket 1 in the open state is pressed (driven) in a substantially tangential direction to the rotation locus by the resultant force of the driving means and the auxiliary driving means. Will be.

That is, according to such a configuration, the bucket 1 in the opened state is also driven by the hydraulic cylinder 4 that serves as an auxiliary drive means, and here, the driving force is applied from a substantially tangential direction with respect to the rotation locus. As a result, the operating directions are substantially the same, and the driving efficiency is good. Therefore, the bucket 1 in the open state can be strongly closed and rotated, and the bucket 1 in the open state can be strongly rotated.
Can be strongly closed and rotated, and the tightening force at the initial stage of the closing operation from the open state can be enhanced.

<< Effects of the Invention >> As described in detail in the above, according to the excavator according to the invention, the bucket in the open state is driven by the auxiliary drive means at the initial stage of the closing operation. Become. Here, since the driving force is applied from a tangential direction with respect to the rotation locus, the action directions are substantially the same, and the driving efficiency is excellent. Therefore, the bucket in the open state can be strongly closed and rotated, and the tightening force at the initial stage of the closing operation that requires the largest tightening force can be increased.

[Brief description of drawings]

 FIG. 1 is a side view showing an embodiment of the present invention. 1 ... Bucket 3 ... Hydraulic cylinder 4 ... Hydraulic cylinder (auxiliary driving means) 12 ... Pivot shaft

Claims (1)

(57) [Scope of utility model registration request] 1. A so-called clamshell type in which opposed and paired buckets are opened and closed by being rotated around a pivot by a driving means such as a hydraulic cylinder, and the buckets in an open state are driven by the driving means. An excavating device comprising: an auxiliary drive unit that drives from a substantially horizontal direction so that a resultant force with the unit becomes a substantially tangential direction with respect to a rotation locus.