JPH10131227A - Multi-stage expansion arm for deep-hole excavator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase the expansion speed and improve the work efficiency in a deep-hole excavator expanding a multi-stage expansion arm via the action of two cylinders. SOLUTION: In this multi-stage expansion arm 3 for a deep-hole excavator, the outer tube 3a and intermediate tube 3b of the expansion arm 3 are connected by the first cylinder 6, and the intermediate tube 3b and an inner tube 3c are connected by the second cylinder 7. A chamber A on the rod side of the first cylinder 6 and a chamber B on the tube side of the second cylinder 7 are communicated by a pipe 8. The pressure receiving area of the chamber A and the pressure receiving area of the chamber B are made equal, and the hydraulic oil is filled in the chambers A, B and the pipe 8. The first cylinder 6 and the second cylinder 7 are concurrently operated at the same expansion stoke, the inner tube 3c is moved against the outer tube 3a at the speed two times that of the intermediate tube 3b, and the expansion speed of the expansion arm 3 is increased.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multistage telescopic arm of a deep hole excavator, and more particularly to an improvement in the telescopic speed of a telescopic arm comprising an outer cylinder, an intermediate cylinder and an inner cylinder.

[0002]

2. Description of the Related Art As shown in FIG. 4, a general configuration of a deep hole excavator having a multi-stage telescopic arm is as follows. Is pivoted. The telescopic arm 3 can be turned up and down by the operation of an arm cylinder 4, and a clam bucket 5 is attached to the tip of the telescopic arm 3.

The telescopic arm 3 comprises an outer cylinder 3a, an intermediate cylinder 3b, and an inner cylinder 3c, and the two cylinders 6, 7 extend and retract to extend and contract the intermediate cylinder 3b and the inner cylinder 3c from the outer cylinder 3a. The total length of the arm 3 changes.

When excavating a vertical hole, as shown by a two-dot chain line, the arm cylinder 4 is extended to bring the telescopic arm 3 upright. If the telescopic arm 3 is extended downward while excavating with the clam bucket 5, the position of the clam bucket 5 is lowered and excavation can be performed from the ground surface to a deep position.

[0005]

A conventional deep hole excavator is:
The total length of the telescopic arm is changed by the operation of the two cylinders. For example, when the telescopic arm is extended, the first cylinder starts operation and the intermediate cylinder is extended from the outer cylinder. After the stroke to the position, the second cylinder is operated to draw out the inner cylinder from the intermediate cylinder. Similarly, when the telescopic arm is contracted, one cylinder completes the contraction operation and then the other cylinder contracts. As described above, since the two cylinders are sequentially operated, the expansion and contraction speed of the expansion and contraction arm is low.

Therefore, in a deep hole excavator that expands and contracts a multi-stage telescopic arm by operating two cylinders, there is a technical problem to be solved in order to increase the telescopic speed and improve work efficiency. Therefore, the present invention aims to solve this problem.

[0007]

SUMMARY OF THE INVENTION The present invention has been proposed to achieve the above-mentioned object, and is directed to a deep hole excavator having a multistage telescopic arm comprising an outer cylinder, an intermediate cylinder and an inner cylinder. The outer cylinder and the intermediate cylinder are connected by a first cylinder, the intermediate cylinder and the inner cylinder are connected by a second cylinder, and the rod-side pressure receiving area of the first cylinder and the tube of the second cylinder are connected. And a multi-stage deep hole excavator filled with hydraulic oil by connecting a rod-side port of the first cylinder and a tube-side port of the second cylinder through a conduit. A telescopic arm is provided.

[0008]

Embodiments of the present invention will be described below in detail with reference to the drawings. The same components as those of the general deep hole excavator shown in FIG. 4 are denoted by the same reference numerals, and description thereof will be omitted. FIG. 1 shows a telescopic mechanism of the telescopic arm 3, in which a first cylinder 6 is provided between an outer cylinder 3a and an intermediate cylinder 3b, and a rod 6a of the first cylinder 6 is connected to the outer cylinder 3a. The tube 6b of the first cylinder 6 is connected to the intermediate cylinder 3b. Also, a second cylinder 7 is provided between the intermediate cylinder 3b and the inner cylinder 3c, the rod 7a of the second cylinder 7 is connected to the inner cylinder 3c, and the tube 7b of the second cylinder 7 is connected to the intermediate cylinder 3b. connect.

Here, the pressure receiving area of the chamber A (rod side) of the first cylinder 6 and the pressure receiving area of the chamber B (tube side) of the second cylinder 7 are formed to be equal. The port and the port of the chamber B are communicated with each other through the pipe 8, and the hydraulic oil is filled in the chambers A and B and the pipe 8 in advance. Therefore, A
When the hydraulic oil in the chamber and the chamber B moves, the first cylinder 6 and the second cylinder 7 expand and contract simultaneously, and the first and second cylinders 6 and 7 have the same pressure receiving area in the chambers A and B. Have the same expansion / contraction stroke.

Further, a pipeline 10 extending from a hydraulic operating section 9 provided on the body 1 side of the deep hole excavator and a pipeline 11 contracting from a hydraulic operation section 9 are provided.
And connect the extension-side pipe 10 to the C chamber (tube side) of the first cylinder 6 and the contraction-side pipe 11
Is connected to the D chamber (rod side) of the second cylinder 7. Further, a hose sheave 12 is pivotally mounted on the intermediate cylinder 3b, and the contraction side pipe 11 is wound around the hose sheave 12.

Thus, when the telescopic arm 3 is extended,
If hydraulic oil is supplied to the C chamber of the first cylinder 6 through the extension side pipe line 10, the volume of the C chamber increases and the first cylinder 6 expands. At this time, the hydraulic oil discharged from the A chamber of the first cylinder 6 passes through the pipeline 8 and is led out to the B chamber of the second cylinder 7, and the volume of the B chamber increases to increase the volume of the second cylinder. 7 elongates.

As described above, since the pressure receiving areas of the chambers A and B are equal, the first cylinder 6 and the second cylinder 7 extend simultaneously with the same stroke. Therefore, as shown in FIG. 2, the moving distance of the intermediate cylinder 3b with respect to the outer cylinder 3a and the moving distance of the inner cylinder 3c with respect to the intermediate cylinder 3b are equal. That is, the amount of movement of the inner cylinder 3c with respect to the outer cylinder 3a is twice that of the intermediate cylinder 3b, and the inner cylinder 3c moves in the direction of extension at twice the speed of the intermediate cylinder 3b.

Since the movement amount of the intermediate cylinder 3b with respect to the outer cylinder 3a and the movement amount of the inner cylinder 3c with respect to the intermediate cylinder 3b are equal, the hose sheave 1
There is no need to adjust the length of the conduit 11 on the contraction side wound around 2, and the length of the hose may be constant.

On the other hand, when the telescopic arm 3 is contracted, the operating oil is supplied to the D chamber of the second cylinder 7 from the state shown in FIG. The volume increases and the second cylinder 7 contracts. At this time, the second
Hydraulic oil discharged from the B chamber of the cylinder 7 passes through the pipeline 8 and is led out to the A chamber of the first cylinder 6, and the volume of the A chamber increases and the first cylinder 6 contracts.

The first cylinder 6 and the second cylinder 7
Contracts simultaneously with the same stroke, as shown in FIG. 1, the amount of movement of the inner cylinder 3c with respect to the intermediate cylinder 3b and the amount of movement of the intermediate cylinder 3b with respect to the outer cylinder 3a become equal. It moves in the contraction direction at twice the speed.

As described above, regardless of whether the telescopic arm 3 is extended or contracted, the first and second cylinders 6 and 7 operate simultaneously and the intermediate cylinder 3b and the inner cylinder 3c move simultaneously. The expansion and contraction speed of the expansion and contraction arm 3 is increased.

In the present embodiment, the first cylinder 6
Is connected to the outer cylinder 3a and the rod 7a of the second cylinder 7 is connected to the inner cylinder 3c. However, the cylinder may be mounted with the rod direction reversed. For example, FIG.
Has the rod 7a connected to the intermediate cylinder 3b with the second cylinder 7 turned in the opposite direction.
When the telescopic arm 3 is extended and retracted, the first and second cylinders 6,
7 operate at the same time, and the telescopic arm 3 expands and contracts faster.

Thus, the present invention can be variously modified without departing from the spirit of the present invention, and it goes without saying that the present invention extends to the modified ones.

[0019]

As described above, according to the present invention, the rod side of the first cylinder and the tube side of the second cylinder communicate with each other through the pipeline, and the return oil when one cylinder is operated is used for the other. By leading the cylinder to the working side, both cylinders are simultaneously operated. Therefore, the intermediate cylinder and the inner cylinder move at the same time, and the inner cylinder moves at twice the speed of the intermediate cylinder, so that the expansion / contraction speed of the telescopic arm is increased and the work efficiency can be improved.

[Brief description of the drawings]

 The figure shows an embodiment of the present invention.

FIG. 1 is an explanatory view showing a telescopic mechanism of a telescopic arm during contraction.

FIG. 2 is an explanatory view showing a telescopic mechanism of a telescopic arm at the time of extension.

FIG. 3 is an explanatory view showing a telescopic mechanism of a telescopic arm when a mounting direction of a cylinder is changed.

FIG. 4 is a side view of a general deep hole excavator having a multi-stage telescopic arm.

[Explanation of symbols]

 3 Telescopic arm 3a Outer cylinder 3b Intermediate cylinder 3c Inner cylinder 6 First cylinder 7 Second cylinder 6a, 7a Rod 6b, 7b Tube 8 Pipe

Claims (1)

[Claims] In a deep hole excavator provided with a multi-stage telescopic arm comprising an outer cylinder, an intermediate cylinder and an inner cylinder, the outer cylinder and the intermediate cylinder are connected by a first cylinder, and the intermediate cylinder and the intermediate cylinder are connected to each other. The inner cylinder is connected by a second cylinder, the rod-side pressure receiving area of the first cylinder and the tube-side pressure receiving area of the second cylinder are made equal, and the rod-side port of the first cylinder is further formed. A multi-stage telescopic arm for a deep hole excavator, characterized in that a hydraulic fluid is filled by connecting a pipe line with a port on the tube side of the second cylinder.