JPH0988470A - Telescopic drill rod - Google Patents

Abstract

PROBLEM TO BE SOLVED: To lengthen the excavation length per rod, reduce the number of loading and unloading times of rods and to promote efficiency of excavation work by fitting the rods to each other in a movable manner in the direction of the axis to make them as expansible multiple-rods. SOLUTION: Rods 1-5 are fitted to each other in the axial direction, and a drill rod 10 is constituted of expansible multiple-rods. In this constitution, coupling devices consisting of a coupling bar 6 and a coupling pipe 8 are provided to the ends in opposition to each other of the outermost rod 1 and innermost rod 5. Inside thick sections 11 having a plurality of groves extended in the direction of the axis are provided to the inside circumferences of the rods 1-4 except the innermost rod 5. Then, kelleys 13 and 14 extended in the direction of the axis are provided to the circumferences of the rods 2-5 except the outermost rod 1. The kelleys 13 and 14 are capable of moving inside the grooves of the inside thickness sections 11 and are capable of interlocking with the inside thickness sections 11, and torque and axial force are transferred between the inside and outside rods adjacent to each other.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a telescope type drill rod. More particularly, it relates to a telescopic drill rod used as a tool for large diameter excavators.

[0002]

2. Description of the Related Art Conventionally, for example, when excavating a large-diameter hole for cast-in-place piles, a drilling bucket or an auger is attached to the tip of a kelly bar for excavation. Kelly bar is a telescope type that generally expands and contracts in a few steps.
Due to the expansion and contraction operation, the drilling bucket and auger are repeatedly moved up and down to perform earth removal work.

If the excavation depth is less than the maximum extension length of the kelly bar, efficient excavation work is performed. However, if the drilling depth is more than the maximum extension length of the kelly bar, the drill rods must be sequentially connected to the kerry bar. For this reason, the drill rod must be frequently attached and detached every time soil is removed, and efficient excavation work cannot be performed. In particular, when the height of the excavation site is limited, it is not possible to use a long telescope type kelly bar or a long drill rod, so a large number of short drill rods are used. As a result, the number of times the drill rod is attached and detached increases.

[0004]

SUMMARY OF THE INVENTION The present invention has been made on the basis of the above technical background, and has the following objects.

An object of the present invention is to provide a telescope type drill rod which can reduce the number of times of attaching and detaching the rod and can perform an efficient excavation work.

[0006]

The present invention employs the following means in order to achieve the above object.

That is, the present invention is a drill rod composed of multiple rods in which the rods are fitted to each other so as to be movable in the axial direction, and the rods are arranged at opposite ends of the outermost rod and the innermost rod. Provided connecting means,
An inner thick portion provided on the inner circumference of each rod except the innermost rod and having a plurality of grooves extending in the axial direction, and an axially extending portion provided on the outer circumference of each rod except the outermost rod, wherein the groove is formed. A telescope type drill rod movable inside and engageable with the inner thick portion, comprising a kerry for transmitting a rotational force and an axial force between adjacent inner and outer rods. is there.

Further, according to the present invention, there is provided a telescope type drill rod provided on the outer circumference of the lower end of each rod except the outermost rod and provided with an outer thick portion capable of engaging with the inner thick portion when the rod is extended. It is in.

Further, according to the present invention, the first kelly which can be engaged with the inner thick portion when the rods are shortened,
A telescope type drill rod characterized by comprising a second kelly capable of engaging with the thick inside portion when each rod is extended.

Further, according to the present invention, upper and lower ends of the first kelly are formed with shoulder portions which are respectively engageable with upper and lower ends of the inner thick part, and upper ends of the second kelly are upper ends of the inner thick part. A telescopic drill rod is characterized in that a shoulder portion capable of engaging with is formed.

Further, the present invention provides the first kelly and the second kelly.
The telescope type drill rod is characterized in that a gap for supporting the rod holder is formed between the kelly and the kelly.

According to the present invention, the telescope type drill rod is used by being sequentially extended as the digging depth becomes deeper. Therefore, the excavation length per rod becomes long, and the required number of rods is reduced, so that the number of attachments and detachments is reduced and the efficiency of excavation work can be increased.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an axial sectional view showing a fully shortened state of a telescopic drill rod according to the present invention,
2 is a sectional view taken along the line AA of FIG. 1 showing the shortened locked state, FIG. 3 is a sectional view taken along the line BB of FIG. 1, and FIG. 4 is a sectional view taken along the line AA of FIG. 1 showing the fully extended state. .

The telescope type drill rod 10 has a quintuple pipe structure in this embodiment, and each of the rods 1 to
5 are fitted to each other so as to be movable in the axial direction. The lower end of the outermost rod 1 is closed, and a connecting bar 6 having a square cross section is provided at the closed end. A pin insertion hole 7 is formed in the connecting bar 6. At the upper end of the innermost rod 5, a connecting cylinder 8 into which the connecting bar 6 is fitted is provided. A pin insertion hole 9 is formed in the connecting cylinder 8.

On the inner circumferences of the rods 1 to 4 excluding the innermost rod 5, an annular thick inner wall portion 11 having a predetermined axial length is provided. The inner thick portion 11 is formed with a plurality of grooves 12 extending in the axial direction at equal angular intervals (see FIGS. 2 to 4). On the other hand, a first kelly 13 and a second kelly 14 extending in the axial direction are provided corresponding to the groove 12 on the outer circumferences of the rods 2 to 4 except the outermost rod 1. In addition, each rod 2 except the outermost rod 1
An annular outer thick portion 15 is provided on the outer periphery of the tip of the ring 5. The outer thick portion 15 is engageable with the lower end of the inner thick portion 11 when the rod is extended.

The first kelly 13 and the second kelly 14 are grooves 1.
It is possible to move in 2 in the axial direction. The first kelly 13 is formed with a notch 16 extending in the axial direction, and thereby shoulders 17 and 18 are formed at both ends. The cutout 16 is engageable with the wall portion of the groove 12 when the rod is in the shortened state, and the shoulder portions 17 and 18 are engageable with the upper and lower ends of the inner thick portion 11, respectively, when engaged.

The second kelly 14 is also formed with a notch 19 extending in the same direction, and a shoulder portion 20 is formed only at the upper end. The notch 19 is engageable with the wall portion of the groove 12 in the extended state of the rod, and the shoulder portion 20 is engageable with the upper end of the inner thick portion 11 when engaged.

A gap 21 is formed between the first kelly 13 and the second kelly 14, and the rod holder 22 of the excavator is formed in the gap 21 when the rod is extended or shortened or when the telescopic rod 10 is connected. Is inserted. That is, the shoulder portion 18 of the first kelly 13 has the telescopic rod 10
Has a function of a holder seat for supporting the rod holder 22 on the rod holder 22. Since no kelly is provided on the outermost rod 1, a dedicated annular holder seat 23 is provided. The hole 2 provided in the upper peripheral wall of the innermost rod 5
Reference numeral 4 is for inserting a bar (not shown) for rotating the rods 1 to 5 at the time of extension / shortening operation.

State of Use The telescopic rod 10 is suspended by connecting a kelly bar (not shown) to the connecting tube 8 of the innermost rod 5. A drilling bucket (not shown) or the like is connected to the connecting bar 6 of the outermost rod 1.

When the telescope type rod 10 is in the contracted state, the notches 16 of the first kelly 13 are formed in the groove 12 by rotating the rods 2 to 5 clockwise in FIGS.
Is engaged with the wall portion of the sheet (see the development view of FIG. 6). In this state, the shoulder portion 18 of the first kelly 13 of each rod 2 to 5 engages with the lower end of the inner thick portion 11 of each of the rods 1 to 4 on the outside thereof, and each rod 1 to 4 moves vertically. Supported. Then, due to the engagement between the first kelly 13 and the wall portion of the groove 12, the rotational force of the innermost rod 5 is sequentially transmitted to the outer rods 1 to 4. Further, the axial force applied to the innermost rod 5 is generated by engaging the shoulder portion 17 of the first kelly 13 with the upper ends of the thick inner portions 11 of the rods 1 to 4 on the outer sides thereof. It is sequentially transmitted to the rods 1 to 4. In this way, excavation in a shortened state is performed.

In the shortened state, the stopper 2 as shown in FIG.
5 is used. The stopper 25 is an elongated member having a shoulder portion 26 and a handle 27 on the upper portion. The stopper 25 is inserted into the groove 12 until the shoulder 26 abuts the shoulder 17 of the first kelly 13 with the first kelly 13 engaged with the wall of the groove 12, whereby the respective rods 1 to 5 of the rods 1 to 5 are inserted. Relative rotation is blocked and locked in the shortened state (see Figure 2).

The extension operation of the first stage is performed as follows. The rod holder 22 has a holder seat 2 for the outermost rod 1.
3 is set, and the stopper 25 between the outermost rod 1 and the rod 2 inside thereof is removed. And the innermost rod 5
A bar for rotation is inserted into the hole 23 of and the innermost rod 5 is rotated counterclockwise in FIGS. As a result, the engagement between the wall portion of the groove 12 of the outermost rod 1 and the notch 16 of the first kelly 13 of the rod 2 inside thereof is released, and the first and second
The kerry 13 and 14 can move in the groove 12. When the innermost rod 5 is lifted in this state, the innermost rod 5 is pulled out from the outermost rod 1 along with the outer rods 2 to 4 (see FIG. 8).

Then, when the innermost rod 5 is rotated clockwise in FIGS. 2 and 3, the notch 19 of the second kelly 14 is engaged with the wall portion of the groove 12 of the outermost rod 1 (expansion of FIG. 7). See figure). During excavation, the rotational force is transmitted between the outermost rod 1 and the rod 2 inside thereof by the engagement of the second kelly 14 and the groove 12, and the shoulder portion 2 of the second kelly 14 is transmitted.
The axial force is transmitted by the engagement between 0 and the inner thick portion 11.

When extending the second stage, as shown in FIG. 8, the first kelly 13 and the second kelly 14 of the rod 2 are operated.
The rod holder 22 is set in the gap 21 between the and, and the same operation as described above is performed. Hereinafter, as the excavation depth becomes deeper, the same extension operation is repeated. FIG. 9 shows a state in which all stages are extended.

To shorten from the extended state, for example, when shortening from the all-stage extended state, the rod 4 outside the innermost rod 5 is set in the rod holder 22 as shown in FIG. Then, the innermost rod 5 is rotated clockwise to release the engagement between the second kelly 14 and the groove 12, and then the innermost rod 5 is hung down and rotated counterclockwise so that the first kelly 13 is grooved. 12 is engaged and the stopper 25 is set. Thereafter, similarly, the rods on the inner side are sequentially accommodated in the rods on the outer side and shortened. The extension / shortening operation as described above is repeated every time the earth removing work is performed.

When the digging depth becomes deeper, a new telescope type drill rod 10 is connected to the telescope type drill rod 10. FIG. 10 shows a state in which the telescopic drill rods 10 are connected to each other. At that time, the innermost rod 5 of the preceding telescope type drill rod 10 is set in the rod holder. The connecting bar 6 of the following telescope type rod 10 is inserted into the connecting cylinder 8 and the connecting pin 30 is inserted into the pin insertion holes 7 and 9 to connect both telescope type rods 10 and 10.

The above embodiment is merely an example, and the present invention can be modified in various ways. For example, in the above embodiment, the innermost rod is on the upper side and the outermost rod is on the lower side during extension, but it may be upside down.
Further, the structure is not limited to the quintuple pipe structure, and other multi-tube structure may be used.

[0028]

As described above, according to the present invention, since the excavation length per rod becomes long, it is possible to reduce the number of times of attaching and detaching the rod and to perform an efficient excavation work.

[Brief description of drawings]

FIG. 1 is an axial sectional view showing a fully shortened state of a telescope type drill rod according to the present invention.

FIG. 2 is a sectional view taken along the line AA of FIG. 1 showing a shortened lock state.

3 is a sectional view taken along line BB of FIG.

FIG. 4 is a cross-sectional view taken along the line AA of FIG. 1 showing a fully extended state.

FIG. 5 is a perspective view showing a stopper.

FIG. 6 is a development view showing an engaged state of the kelly at the time of shortening.

FIG. 7 is a development view showing an engaged state of the kelly at the time of extension.

FIG. 8 is a cross-sectional view showing the extended state of the first stage.

FIG. 9 is a cross-sectional view showing a fully extended state.

FIG. 10 is a cross-sectional view showing a connected state of telescopic rods.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Outermost rod 5 ... Innermost rod 6 ... Connection bar 8 ... Connection cylinder 10 ... Telescope type rod 11 ... Inner thick part 12 ... Groove 13 ... 1st kelly 14 ... 2nd kelly 15 ... Outer thick part 16 , 19 ... Notches 17, 18, 20 ... Shoulder 21 ... Gap 22 ... Rod holder 23 ... Holder seat

Claims (5)

[Claims] 1. A drill rod composed of multiple rods, in which each rod is fitted to each other so as to be movable in the axial direction and is expandable and contractible, and the drill rods are provided at opposite ends of an outermost rod and an innermost rod. A connecting means, an inner thick part provided on the inner circumference of each rod except the innermost rod and having a plurality of grooves extending in the axial direction, and an outer peripheral surface of each rod excluding the outermost rod extending in the axial direction. And a kelly movable in the groove and engageable with the inner thick part, and including a kelly for transmitting a rotational force and an axial force between the inner and outer rods adjacent to each other. Shaped drill rod. 2. The telescope type according to claim 1, further comprising an outer thick portion provided on the outer periphery of the lower end of each rod except the outermost rod and engageable with the inner thick portion when the rod is extended. Drill rod. 3. The kelly comprises a first kelly that can be engaged with the inner thick portion when the rods are shortened, and a second kelly that can be engaged with the inner thick portion when the rods are extended. The telescope type drill rod according to claim 1 or 2, characterized in that. 4. Upper and lower ends of the first kelly are formed with shoulders that can be respectively engaged with upper and lower ends of the inner thick part, and upper ends of the second kelly are engaged with upper ends of the inner thick parts. 4. Telescopic drill rod according to claim 3, characterized in that a possible shoulder is formed. 5. The telescope type drill rod according to claim 3, wherein a gap for supporting a rod holder is formed between the first kelly and the second kelly.