JP3286820B2 - Earth drill - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an earth drill for drilling a pit in the ground.

[0002]

2. Description of the Related Art As shown in FIG. 1, a main body of a conventional earth drill is constituted by a traveling crane 1 having a boom 2 and a hoisting rope 8 of the crane 1 supports a drilling bucket 3. The excavating bucket 3 is attached to a lower end of a kelly bar 4, and the kelly bar 4 is attached to an upper frame 6 of a front frame 5 so as to be able to move up and down via a thrust cylinder 7.
Is inserted into the hole. The upper end of the kelly bar 4 is connected to a hoisting rope 8 via a joint fitting 9 such as a swivel joint. The hoisting rope 8 is paid out from a winch 10 installed on the main body, and is hung on a sheave 11 attached to the tip of the boom 2. By driving the kelly drive device 7, the kelly bar 4 and the excavation bucket 3 rotate.

[0003]

In such an earth drill, there is a problem that a so-called miso rubbing motion of a drilling bucket occurs during a drilling operation, and the center position of a pile hole cannot be determined.

The present invention has been made in view of the above, and has a structure in which a kelly bar is supported at two upper and lower portions of a kelly drive device and a guide device, and a hole for inserting the kelly bars of both devices, or a positioning of the hole and the key groove. It is an object of the present invention to provide an earth drill that can easily perform the above.

[0005]

SUMMARY OF THE INVENTION The present invention provides an earth drill body, a front frame supported on the earth drill body so as to be able to undulate, a kelly drive device mounted on the front frame via a thrust cylinder, and In the earth drill including a kelly bar rotatably and axially movably inserted into a kelly drive device and a drilling bucket attached to a lower end of the kelly bar, a guide device for receiving the kelly bar is provided on the front frame. characterized by being configured to support at upper and lower positions of the buttoned <br/> over drive device and the guide device in the front frame. At the lower part of the Kelly drive device, a guide pin and a positioning guide are attached, and the guide pin matches the positioning guide of the Kelly drive device with the positioning pin and the phase of the guide pin when both positioning guides match. Holes for inserting guide pins. Further, a receiving plate for receiving the lower end of the key of the kelly bar is provided on the upper portion of the guide device when the key grooves of the kelly drive device and the guide device do not match.

[0006]

[Function] When setting up the earth drill, lower the Kelly drive device so that the positioning guide of the device matches the positioning guide of the guide device, and the guide pins of the Kelly drive device and the pin holes of the guide device match. I do. When the Kelly drive device is further lowered in this state, the guide pin is inserted into the pin hole, and the hole for inserting the Kelly bar of the Kelly drive device and the guide device, or the hole and the keyway match. In that state, Keriba is inserted into both devices. During the excavation work, the kelly bar is supported at two upper and lower locations by the kelly drive device and the guide device.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of an earth drill having a round kelever will be described below with reference to FIGS.

Guide frames are formed on the left and right sides of the upper frame 6 of the front frame 5, and a Kelly drive device 7 is attached to the guide frames so as to be able to move up and down via a thrust cylinder (not shown). Have been. Kelly drive unit 7, like the conventional ones, equipped with a geared shaft which is thus driven to the hydraulic motor pinion, Its geared shaft, round Keriba 4
And a plurality of, for example, three key grooves 7b provided on the peripheral wall of the round kelly bar 4 in the longitudinal direction. The geared shaft is supported by the upper frame 6 via a bearing. A guide pin 12 and a positioning indicator 13 are attached to the periphery of the lower end of the kelly drive device 7.

In the lower portion of the upper frame 6, a guide device 1 is provided.
4 is rotatably supported. The lower plate 15 of the guide device 14, the torque transmitting piece 16 fixed on the lower plate 15 by bolts, and the upper plate 17 have a hole through which the round kelly bar 4 is inserted and a key groove 14a into which the key 4a is inserted. Is provided. Brackets 25 are mounted on the lower plate 15 at intervals in the circumferential direction. Each bracket 25 is mounted with a shaft 19 that supports a guide roller 18 that receives the round kelly bar 4. The guide roller 18 is for maintaining the vertical accuracy of the kerry bar 4 and does not receive a rotational force. A positioning indicator 20 for matching the positioning indicator 13 of the Kelly drive device 7 is attached to the upper plate 17, and a pin whose phase matches the guide pin 12 of the Kelly drive device 7 when the two indicators 13 and 20 match. A hole 21 is provided. In the inner peripheral edge portion between the respective key grooves 14a of the upper plate 17, when the key groove 7b of the Kelly drive device 7 and the key groove 14a of the guide device 14 do not match,
An arc-shaped receiving plate 22 for receiving the lower end of the key 4a of the round kelly bar 4 is attached.

At the lower part of the upper frame 6, a center joint 23 for sending pressure oil to the hydraulic cylinder of the bottom-extended excavating bucket is installed. At the lower part of the center joint 23, a reel table 24 having a hose reel and a cable reel mounted thereon. Is installed.

At the time of setting up the operation of the earth drill, the round kelly bar 4 is not inserted into the kelly drive device 7.
In order to make the work state, the kelly drive device 7 is lowered so that the guide pin 12 does not contact the guide device 14 and rotated, and the positioning pointer 13 is made to coincide with the positioning pointer 20 as shown in FIG. At this time, since the phases of the guide pin 12 and the pin hole 21 match, if the kelly drive device 7 is further lowered, the guide pin 12 is inserted into the pin hole 21. In this state, the key groove 7b of the kelly drive device 7 and the key groove 14a of the guide device 14 match, so that when inserting the round kelly bar 4 from above, the key 4a of the round kelly bar 4 and the key of the kelly drive device 7 are set. The alignment with the groove 7b can be easily performed by rotating the Kelly drive device 7. The alignment between the kelly drive device 7 and the guide device 14 can be performed by means such as a limit switch without using the hands, and in that case, further automation is achieved. As mentioned above,
Since the key groove 7b of the kelly drive device 7 and the key groove 14a of the guide device 14 match, the round kelly bar 4 can be inserted smoothly. After the Kelly drive device 7 and the guide device 14 are aligned, temporarily
As shown in the figure, the round kelly bar 4 can be inserted without any trouble even when the kelly drive device 7 is raised.

In the state of FIG. 5, when the phase of the key groove 7b of the kelly drive device 7 and the phase of the key groove 14a of the guide device 14 do not match, if the round kelly bar 4 is inserted,
The round kelly bar 4 comes into contact with the guide device 14 after passing through the kelly drive device 7, but the lower end of the key 4a is received by the receiving plate 22, and the round kelly bar 4 stops at that position. This can prevent the key 4a from being damaged by hitting the guide roller 18 or the like.

At the time of excavation work, the round kelly bar 4 is supported at two upper and lower locations of a kelly drive device 7 and a guide device 14.

[0014]

According to the first, second and third aspects of the present invention, the kelly bar is vertically supported at the two upper and lower portions of the kelly drive device and the guide device, so that the verticality of the kelly bar is maintained and the center of the pile hole is shifted. Can be prevented, and accurate pile construction can be performed. Further, the positioning of the kelly drive device and the guide device can be easily performed, and the kelly bar can be smoothly inserted into both devices. Furthermore, according to the third aspect, when the key grooves of the kelly drive device and the guide device do not match, the key of the round kelly bar is received by the receiving plate, and damage to the guide rollers and the like can be prevented.

[Brief description of the drawings]

FIG. 1 is a side view showing an embodiment of an earth drill according to the present invention;

FIG. 2 is an enlarged front view taken along line AA of FIG. 1;

FIG. 3 is a plan view of a cross section taken along line BB of FIG. 2;

FIG. 4 is an enlarged plan view taken along the line CC of FIG. 2;

FIG. 5 is a view showing a state where the Kelly drive device is raised from the state of FIG. 2;

FIG. 6 is an enlarged perspective view showing a matching state between a positioning indicator of the Kelly drive device and a positioning indicator of the guide device in FIG. 2;

FIG. 7 is an enlarged cross-sectional front view showing a state in which the lower end of the key of the round keriba is received by the receiving plate of the guide device according to the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 4 round kelly bar 4a key 5 front frame 6 upper frame 7 kelly drive device 7b key groove 12 guide pin 13 positioning guide 14 guide device 14a key groove 15 lower plate 16 torque transmitting piece 17 upper plate 18 guide roller 20 positioning guide 21 Pin hole 22 Receiving plate

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) E21B 11/00 E21B 17/10

Claims (3)

(57) [Claims] 1. An earth drill body, a front frame supported on the earth drill body so as to be able to undulate, a kelly drive device mounted on the front frame via a thrust cylinder, Keriba inserted movably in the axial direction,
In ground drill equipped with a bucket attached to the lower end of the Keriba, a guide device for receiving the Keriba said front frame, said Keriba furo
Ground drill, characterized by being configured to support the in cement frame Kelly drive the upper and lower two places of the gas <br/> id device. 2. An earth drill body, a front frame supported on the earth drill body so as to be able to undulate, a kelly drive device mounted on the front frame via a thrust cylinder, Keriba inserted movably in the axial direction,
In an earth drill having a drilling bucket attached to the lower end of the kelly bar, a guide device for receiving the kelly bar is provided on the front frame, and the kelly bar is configured to be supported at two upper and lower positions of a kelly drive device and a guide device, at the bottom of the Kelly drive device, fitted with a positioning guide with the guide pin, the guide device, said guide pin and the phase in the matched state of the positioning guidelines and both positioning guide to match the positioning guide kelly drive device An earth drill characterized by providing matching guide pin insertion holes. 3. An earth drill body, a front frame supported on the earth drill body so as to be able to be raised and lowered, a kelly drive device mounted on the front frame via a thrust cylinder, An earth drill having a keyed round kelly bar movably inserted in the axial direction and a drilling bucket attached to a lower end of the keyed round kelly bar, wherein a guide device for receiving the round kelly bar is provided on the front frame; Is supported at the upper and lower positions of the Kelly drive device and the guide device, and a guide pin and a positioning guide are attached to the lower part of the Kelly drive device, and the guide device matches the positioning guide of the Kelly drive device. The positioning pointer to be adjusted A guide pin insertion hole that matches the phase of the guide pin is provided, and a receiving plate that receives the lower end of the key of the kelly bar when the key groove between the kelly drive device and the guide device does not match is provided above the guide device. An earth drill characterized by being provided.