JP3366611B2 - Keriba equipment - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a kelly bar apparatus for a construction machine used in a ground drilling method or the like, and more specifically, a kelly bar having a high strength quality at the tip of the inner kelly bar and easy to disassemble and assemble. It relates to the device.

[0002]

2. Description of the Related Art A construction machine used for an earth drill method or the like is provided with a kerry bar device for rotating a bucket for excavation. FIG. 6 shows a conventional example of this type of kelly bar apparatus. This kelly bar device is a cylindrical outer kelly bar A that is rotationally driven by a kelly bar drive device that is composed of a hydraulic motor and a gear reducer (not shown), and is engaged with the outer kelly bar A in the rotational direction so that it can move back and forth in the axial direction. A solid shaft-shaped inner kelly bar B to be inserted is provided. Then, a pin insertion hole for detachably connecting a bucket for excavation (not shown) with a connecting pin to a connecting portion C formed in a rectangular cross section of the tip portion of the inner kelly bar B protruding from the tip of the outer kelly bar A. D is formed.

The inner kelly bar B is rotationally driven by the kelly bar drive device via the outer kerry bar A and advances downward with respect to the outer kerry bar A to impart an excavating force to the bucket (not shown). After drilling
When the bucket is wound up, the inner kelly bar B is retracted into the outer kelly bar A and holds the outer kelly bar A. Therefore, the outer kelly bar A is caught by the inner kelly bar B due to the inclusion of foreign matters and the like, and rises up together when the kelly bar is vibrated to release the catch. An impact force acts on the tip of the kelly bar B. Therefore, in order to reduce this impact force, a buffer coil spring E is provided between the tip of the inner kelly bar B and the tip of the outer kelly bar A.

The coil spring E is a loose spring receiver F which is loosely fitted to the tip of the inner kelly bar B and arranged on the tip side of the outer kelly bar A, and an inner kelly bar B.
It is arranged between a fixed spring receiver G that is welded and fixed to the tip of the inner kelly bar B, and is wound around the tip of the inner kelly bar B. Such a mounting structure of the coil spring E is disclosed in JP-A-7-
This is as seen in Japanese Patent No. 48982.

[0005]

By the way, in the conventional kelly bar apparatus, one fixed spring receiver G of the coil spring E is welded and fixed to the outer periphery of the tip portion of the inner kelly bar B. For this reason, the tip of the inner kelly bar B may be deteriorated in material or weld cracked by the welding heat, and if a shock is applied, the tip of the inner kelly bar B may be deformed or damaged at the welded part. Further, since the fixed spring receiver G cannot be removed from the tip portion of the inner kelly bar B, there is a problem that it is difficult to disassemble and assemble the kerry bar device during work such as repair.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a kelly bar apparatus in which the tip end portion of the inner kelly bar has high strength quality and which is easy to disassemble and assemble. .

[0007]

As a means for solving the above-mentioned problems, the kelly bar apparatus according to the present invention has a tip portion of an inner kelly bar protruding from a tip of a cylindrical outer kerry bar. A kelly bar device in which a cushioning coil spring is interposed between a floating spring receiver that is loosely fitted to the outer periphery and is capable of contacting the tip of the outer kelly bar, and a fixed spring bearing that is fixed to the outer periphery of the tip part of the inner kelly bar. In the above, the fixed spring receiver is divided into an annular groove formed on the outer circumference of the tip portion of the inner kelly bar so as to be engageable in the radial direction, and is integrally detachably fastened to the divided ring member. And a ring member.

In the kelly bar device of the present invention, the split ring member is engaged with the annular groove formed on the outer circumference of the tip of the inner kelly bar so that the fixed spring receiver is fixed to the tip of the inner kelly bar. For this reason, the tip of the inner kelly bar does not undergo material alteration or cracking due to the heat effect of welding heat and the like, and has high strength quality. Also, by removing the ring member from the split ring member, the split ring member can be removed from the tip of the inner kelly bar,
Easy to disassemble and assemble the kelly bar device.

In the kelly bar apparatus of the present invention, the split ring member and the ring member are usually detachably fastened via bolts and nuts.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a kelly bar apparatus according to the present invention will be described below with reference to the drawings. In the drawings to be referred to, FIG. 1 is a half cross-sectional view of a tip portion of a kelly bar device according to an embodiment, FIG. 2 is a front view of a split ring member of a kelly bar device according to an embodiment, and FIG. 3 is a kerry bar according to an embodiment. FIG. 4 is a vertical cross-sectional view of a split ring member of the device, FIG. 4 is a front view of a ring member of the kelly bar device according to one embodiment, and FIG. 5 is a vertical cross-sectional view of the ring member of the kelly bar device according to one embodiment.

As shown in FIG. 1, a kelly bar device according to one embodiment is a cylindrical outer kelly bar 1 which is rotatably driven by a kerry bar drive device composed of a hydraulic motor and a gear reducer (not shown). On the other hand, it is provided with a solid shaft-shaped inner kelly bar 2 which is engaged in the rotational direction and is inserted so as to be able to advance and retreat in the axial direction. The tip of the inner kelly bar 2 projects from the tip of the outer kelly bar 1.

At the tip of the inner kelly bar 2 protruding from the tip of the outer kelly bar 1, a connecting portion 2A having a square cross section is formed.
And a coil spring mounting portion 2B having a circular cross section are formed, and a pin insertion hole 2C for detachably connecting an unillustrated bucket for excavation with a connecting pin is formed in the tip end side connecting portion 2A. There is.

A buffer coil spring 3 is wound around the coil spring mounting portion 2B of the inner kelly bar 2. The coil spring 3 is provided between a floating spring receiver 4 which is loosely fitted to the coil spring mounting portion 2B and abuts on the tip of the outer kelly bar 1 and a fixed spring receiver 5 which is fixed to the tip side of the coil spring mounting portion 2B. It is located in.

The floating spring receiver 4 is in the shape of a perforated ring, and an inverted taper surface 4A capable of contacting the tip of the outer kelly bar 1 is formed on one surface thereof.

On the other hand, the fixed spring receiver 5 has a split ring member 6 which is split in two so as to be radially engageable with an annular mounting groove 2D formed on the tip side of the coil spring mounting portion 2B of the inner kelly bar 2. The ring member 7 is detachably fastened to the split ring member 6 to be integrated therewith.

The split ring member 6 is, as shown in FIG.
It is composed of half ring members 6A and 6B divided into two in the diameter direction, and the inner diameter dimension and the width dimension thereof are the same as those of the annular mounting groove 2 described above.
It is set so that it can be engaged with D without slack. As shown in FIG. 3, the split ring member 6 is formed with a small diameter portion 6C into which the inner circumference of the ring member 7 is fitted and a large diameter portion 6D into which the end surface of the ring member 7 is joined. There is. The large-diameter portion 6D is provided with bolt insertion holes 6E for inserting fastening bolts 8 (see FIG. 1) at four locations in the circumferential direction at equal intervals.

The ring member 7 is the inner kelly bar 2 described above.
Of the split ring member 6 has an inner diameter dimension that fits loosely into the coil spring mounting portion 2B of the split ring member 6 and the outer diameter dimension of the large diameter portion 6D of the split ring member 6.
Is formed to have a size substantially equal to the outer diameter of the. As shown in FIGS. 4 and 5, the ring member 7 is formed with four bolt insertion holes 7A that match the respective bolt insertion holes 6E of the split ring member 6. Further, on one surface of the ring member 7, a nut receiving seat that can receive the nut 9 (see FIG. 1) from the outer peripheral portion of the ring member 7 by radially extending from each bolt insertion hole 7A portion and opening to the outer peripheral portion. 7B is formed.

In order to wind the coil spring 3 around the coil spring mounting portion 2B of the inner kelly bar 2 in the kelly bar apparatus of the present invention constructed as described above, first,
The tip of the inner kelly bar 2 is made to sufficiently project from the tip of the outer kelly bar 1. In this state, the floating spring receiver 4, the coil spring 3, and the ring member 7 are sequentially inserted into the coil spring mounting portion 2B of the inner kelly bar 2.

Next, the inner circumferences of the half ring members 6A and 6B constituting the split ring member 6 are engaged with the annular mounting groove 2D of the coil spring mounting portion 2B in the radial direction. Then, the ring member 7 is fitted into the small diameter portion 6C of the split ring member 6, and the bolt insertion hole 6E of the split ring member 6 and the bolt insertion hole 7A of the ring member 7 are aligned with each other. Further, the nut 9 is inserted into each nut seat 7B from the outer peripheral portion of the ring member 7. Then, the bolt 8 is inserted from the split ring member 6 side into the bolt insertion hole 6E and the bolt insertion hole 7A of the ring member 7 and screwed into the nut 9.

By the above work, the half ring members 6A and 6B of the split ring member 6 are integrated with the ring member 7,
It is held in a fixed state by engaging with the annular mounting groove 2D of the coil spring mounting portion 2B of the inner kelly bar 2. That is, the fixed spring receiver 5 is configured by a combination of the split ring member 6 and the ring member 7. The fixed spring receiver 5 can be removed from the coil spring mounting portion 2B in the reverse order of the above procedure.

In the kelly bar apparatus of one embodiment, the fixed spring receiver 5 fixed to the coil spring mounting portion 2B of the inner kelly bar 2 is detachably constructed by the bolt 8 and the nut 9, so that the kerry bar apparatus is disassembled and assembled. Work can be performed easily. Further, even if the fixed spring receiver 5 is defective due to some impact or the like, it can be easily repaired. In addition, the coil spring mounting portion 2B of the inner kelly bar 2 and the fixed spring receiver 5
Since is not affected by heat such as welding heat at all, high strength quality can be obtained without causing material deterioration or cracking.
As a result, the cushioning effect of the coil spring 3 can be maintained for a long period of time.

[0022]

As described above, according to the kelly bar device of the present invention, the split ring member is engaged with the annular groove formed on the outer periphery of the tip of the inner kelly bar so that the fixed spring receiver is attached to the inner kelly bar. It is fixed to the tip. Therefore, the tip portion of the inner kelly bar does not undergo material alteration or cracking due to the influence of welding heat or the like, and high strength quality can be obtained. Further, by removing the ring member from the split ring member, the split ring member can be removed from the tip portion of the inner kelly bar, so that the disassembling and assembling work of the kelly bar device and the repair of the fixed spring receiver can be easily performed.

[Brief description of drawings]

FIG. 1 is a half cross-sectional view of a tip portion of a kelly bar device according to an embodiment.

FIG. 2 is a front view of a split ring member of the kelly bar device according to one embodiment.

FIG. 3 is a vertical cross-sectional view of a split ring member of the kelly bar device according to one embodiment.

FIG. 4 is a front view of a ring member of the kelly bar apparatus according to the embodiment.

FIG. 5 is a vertical cross-sectional view of a ring member of the kelly bar device according to one embodiment.

FIG. 6 is a half cross-sectional view of a portion corresponding to FIG. 1 of a kelly bar device according to a conventional example.

[Explanation of symbols]

1 ... Outer Keriba 2… Inner Kelly bar 2A ... connecting part 2B ... Coil spring mounting part 2C ... Pin insertion hole 2D ... annular mounting groove 3 ... Coil spring 4 ... Floating spring support 4A ... Inverse taper surface 5: Fixed spring receiver 6 ... Split ring member 6A ... Half ring member 6B ... Half ring member 6C ... Small diameter part 6D ... Large diameter part 6E ... Bolt insertion hole 7 ... Ring member 7A ... Bolt insertion hole 7B ... Nut seat 8 ... bolt 9 ... Nut

Claims (2)

(57) [Claims] 1. A tip of an inner kelly bar protrudes from a tip of a cylindrical outer kelly bar, and a floating spring receiver which is loosely fitted to the outer periphery of the tip of the inner kerry bar and can come into contact with the tip of the outer kerry bar. In a kelly bar device in which a buffering coil spring is interposed between a fixed spring receiver fixed to the outer circumference of the inner kelly bar tip, the fixed spring receiver is provided in an annular groove formed on the outer circumference of the inner kerry bar tip. A kerry bar device comprising: a split ring member that is split so as to be engageable in the radial direction, and a ring member that is detachably fastened to and integrated with the split ring member. 2. The split ring member and the ring member are
The kelly bar device according to claim 1, wherein the kerry bar device is detachably fastened via bolts and nuts.