JPH10220155A - Driving equipment for casing excavating type earth drill - Google Patents

Abstract

PROBLEM TO BE SOLVED: To optimize the quantity of rotation torque for each of kelly-bar and tube by fixing a casing tube rotating gear to a kelley bar drive shaft and arranging a rotating cylinder having an internal gear interlocking with a planetary gear interlocking with the gear stated above. SOLUTION: A kelley-bar drive shaft 19 is rotated and driven by a hydraulic motor 24, and the rotation torque of a casing tube 15 is made higher than the rotation torque of the kelley-bar 14. Then, even though the hydraulic motor 24 is made smaller, it is possible to generate an adequate amount of the rotation torque of the kelley-bar 14 and also of the casing tube 15 respectively. Thus, during excavation work by kelley-bar 14 and during push-in work by the casing tube 15, the transfer of the speed of rotation of the hydraulic motor 24 becomes unnecessary, thereby making the running operation much easier. Also, when performing the excavation work by the kelly-bar 14 and the push-in work by the casing tube 15 at the same time, breaking accidents of the kelly-bar can be prevented. In this way, the work efficiency and total performance can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a casing drilling type earth drill driving apparatus for rotating a kelly bar and a casing tube with a kelly bar drive shaft.

[0002]

2. Description of the Related Art A casing drilling type earth drill performs a pushing operation of a casing tube and a drilling operation in a casing tube by a kelly bar by a single machine. As shown in FIG. 3, the casing tube rotary cylinder 2 is integrally formed with the kellyver drive shaft 1, and the gear 6 fixed to the output shaft 4 of the hydraulic motor 3 meshes with the gear 6 fixed to the kellyver drive shaft 1. Thus, the kelly bar 7 inserted into the kelly bar drive shaft 1 and the casing tube 8 attached to the casing tube rotating cylinder 2 are driven to rotate.

[0003]

However, in the above arrangement, the rotational speed of the kelly bar and the rotational speed of the casing tube are the same, so that the rotational torques of both are the same.
Since the torque for rotating the casing tube is required to be two to three times or more than the torque for rotating the kelly bar, when the casing tube is pushed in, the hydraulic motor is rotated at a low speed to generate a high torque. In addition, it is required to perform an operation switching operation for reducing the torque by rotating the hydraulic motor at a high speed.

In some cases, excavation work and pushing work of the casing tube by the kelly bar are performed at the same time. In this case, a torque larger than the allowable kerry bar is applied, which may lead to a breakage accident of the kelly bar. Furthermore, a kelly bar that can withstand the torque required for the operation of pushing the casing tube is not practical in terms of weight and cost.

Accordingly, the present invention provides a casing which can generate the rotational torque of the kelly bar and the rotational torque of the casing tube as appropriate amounts even with a small hydraulic motor without performing an operation for switching the rotational speed of the hydraulic motor. An object of the present invention is to provide a driving device for a drilling type earth drill.

[0006]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a casing drilling type earth drill driving apparatus for rotating a kelly bar and a casing tube with a kelly bar driving shaft. A casing tube rotating gear is fixedly provided, and a casing tube rotating cylinder having a planetary gear meshing with the casing tube rotating gear and an internal gear meshing with the planetary gear is provided.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on an embodiment shown in FIGS. The earth drill 10 supports a leader 12 erected at a front portion of a main body 11 by a pair of back stays 13 so as to be able to raise and lower, and disposes a kelly bar 14 and a driving device 16 of a casing tube 15 on the leader 12 so as to be able to move up and down. Has been established.

The kelly bar 14 is formed in a shape in which a plurality of keys are provided on the peripheral surface of a square or round cross section, and is hung up and down by a wire rope 18 hung down from a top sheave 17 of the reader 12. The kelly bar driving shaft 19 of the driving device 16 is vertically slidable into a kelly bar insertion hole 20 formed in a kelly bar driving shaft 19, and is rotatably inserted in a restricted relationship.

The driving device 16 is provided with the kerry bar driving shaft 19 rotatably disposed in a vertical direction substantially at the center of a case 22, and a gear 23 fixed above the kelly bar driving shaft 19.
And a gear 26 fixedly mounted on an output shaft 25 of a hydraulic motor 24 disposed above the case 22.

A casing tube rotating gear 27 is fixed to a lower portion of the Kellyver drive shaft 19 protruding from a lower portion of the case 22.
Further, a planetary gear 29 rotatably provided on a shaft 28 protruding from the lower portion of the case 22 is meshed.

A casing tube rotating cylinder 30 is rotatably provided at a lower portion of the case 22, and an internal gear 31 is formed at an upper inner periphery of the casing tube rotating cylinder 30. , And meshes with the internal gear 31. The casing tube 15 is attached to the lower part of the casing tube rotating cylinder 30 so as to be integrally rotatable.

With this configuration, when the kelly bar drive shaft 19 is driven to rotate by the hydraulic motor 24, the rotation torque of the casing tube 15 becomes several times higher than the rotation torque of the kelly bar 14, so that the hydraulic motor 24 is reduced in size. However, the rotational torque of the kelly bar 14 and the rotational torque of the casing tube 15 can be respectively generated as appropriate amounts.

Therefore, it is not necessary to switch the rotation speed of the hydraulic motor 24 during the excavation work by the kerry bar 14 and the pushing work of the casing tube 15, so that the driving operation is facilitated. Further, when the excavation work by the kelly bar 14 and the pushing work of the casing tube 15 are performed at the same time, a breakage accident of the kelly bar 14 can be prevented, so that work efficiency and total performance can be improved. If the shaft 28 has a structure that can be fixed to and released from the case 22, only the excavation work by the kelly bar 14 can be performed without rotating the casing tube 15.

[0014]

As described above, in the casing drilling type earth drill driving device of the present invention, the casing tube rotating gear is fixedly mounted on the kelly bar driving shaft for rotating the kelly bar, and meshed with the casing tube rotating gear. Since the casing tube rotating cylinder having the planetary gear that rotates and the internal gear that meshes with the planetary gear is provided, the rotating torque of the casing tube can be several times higher than the rotating torque of the kelly bar. And the rotating torque of the casing tube can be respectively generated as appropriate amounts.

Therefore, it is not necessary to switch the rotational speed of the hydraulic motor between the excavating operation by the kelever and the pushing operation of the casing tube, so that the driving operation is facilitated. In addition, when the excavation work by the kelly bar and the pushing operation of the casing tube are performed at the same time, the breakage accident of the kelly bar can be prevented, so that the working efficiency and the total performance can be improved.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a driving device according to an embodiment of the present invention.

FIG. 2 is a front view of the earth drill.

FIG. 3 is a cross-sectional view of a conventional driving device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Earth drill, 14 ... Keriba, 15 ... Casing tube, 16 ... Driver, 19 ... Keriba drive shaft,
24: Hydraulic motor, 27: Casing tube rotating gear, 29: Planetary gear, 30: Casing tube rotating cylinder, 31: Internal gear

Claims (1)

[Claims] 1. A casing drilling type earth drill drive device for rotating a kelly bar and a casing tube with a kelly bar drive shaft, wherein a casing tube rotation gear is fixed to the kelly bar drive shaft, and the casing tube rotation gear is provided. And a planetary gear meshing with the planetary gear, and a casing tube rotary cylinder having an internal gear engaged with the planetary gear.