JP2892243B2 - Telescopic Keliva device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a telescopic type kelever device used for an earth drill.

[0002]

2. Description of the Related Art As this kind of conventional telescoping keriba apparatus, for example, one disclosed in Japanese Patent Application Laid-Open No. 2-256788 is known. This will be described with reference to FIG. FIG.
, The kelly bar main body is formed by sequentially extending and retracting the second kelly bar 32 and the outer kelly bar 33 to the inner kelly bar 31 in an extensible manner, and the upper end of the inner kelly bar 31 is connected to a wire rope hanging down from a boom of the earth drill body. A shock absorbing spring 35 is interposed between a spring seat 31a welded to a lower portion of the inner keleaver 31 and a spring seat 34 externally inserted into the inner keeliva 31 so as to be movable up and down. A buffer member 36 made of a non-ferrous metal is screwed with a bolt 41, and the second keriba 32 is placed on the upper surface of the buffer member 36. A nonferrous metal buffer material 38 is also screwed on the top surface of the lower large diameter portion 32a of the second kelly bar 32, and the outer kelly bar 33 is placed on the upper surface of the buffer material 38.

[0003] When a digging bucket (not shown) is connected to the lower end of the inner keriba 31 and the outer keriba 33 is rotated by a rotary drive device (not shown), the rotation is transmitted to the second keriba 32 and the inner keriba 31 in this order, and the digging bucket is rotated. Rotate. In this state,
Is lowered, the ground is excavated by the excavation bucket, and a hole is drilled. When the inner keriba 31 is further lowered, the inner and second keribas 31 and 32 are integrally extended from the outer keriba 33, and the second keriba 32 is extended.
Is extended, the inner keriba 31 extends with respect to the second keriba 32, whereby a hole is deeply formed.

[0004] When discharging the sediment accumulated in the excavation bucket, the inner keriba 31 is raised and contracted with respect to the second keriba 32, and the cushioning material 36 provided on the spring seat 34 becomes the second keriba large-diameter portion 32 a. Although it collides with the lower surface, since the cushioning member 36 is made of a non-ferrous metal material, no loud noise is generated at the time of collision. Further, at the time of collision between the two, the spring 35
Shrinkage absorbs the shock, and large vibration does not act on the earth drill body. Inna Keriva 31
Is raised further, the inner and second keriba 3
1 and 32 integrally contract with the outer keriba 33,
The cushioning material 38 provided on the upper surface of the large diameter portion 32 a collides with the lower surface of the outer keriba 33. Also at this time, the generation of a loud collision sound is prevented by the cushioning member 38. Further, when the both collide, the spring 35 is contracted via the second keriba 32 and the spring seat 34, so that the impact is absorbed as described above.

In the above-described kelly bar device shown in FIG. 9, an example is shown in which the large-diameter portion 32a is integrally formed at the lower end of the second kelly bar 32 in advance. For example, as shown in FIG. 10 and FIG. A kelly bar device of a type in which a split boss 37 is attached to the outer peripheral surface of the lower part of the helical member is also known.
As shown in FIG. 11B, the split boss 37 is composed of a plurality (three in the figure) of boss blocks 37A, and each boss block 37A is formed in a ring shape with a bolt 42 on the lower outer peripheral surface of the second keriba 32 '. It is screwed in. On the upper surface of each boss block 37A, a cushioning material 38 similar to the above is fixed by bolts 41 as shown in FIG.
The split boss 37 is formed with a drain hole HL for discharging muddy water inside the kelly bar device.

[0006]

However, in the two conventional examples described above, both of the cushioning member 38 and the large diameter portion 32 are used.
a, or the upper surface of the split boss 37 is screwed to the upper surface of the divided boss 37 with a bolt 41, so that the work of mounting the cushioning member 38 is troublesome.
In addition, the contact area between the cushioning material 38 and the outer keriba 33 is reduced by the amount of the bolt through hole provided in the cushioning material 38, the surface pressure is increased, and the cushioning material 38 is easily displaced and the replacement frequency is increased. is there. Further, when the upper surface of the cushioning member 38 is depressed, the lower surface of the outer keeliva 33 directly collides with the head of the bolt 41, and the bolt 41 may be damaged and the cushioning member 38 may come off.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a telescopic keriba device capable of attaching a cushioning material without using a bolt on the upper part of a split boss.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1 showing an embodiment, the present invention is directed to a first kelly bar (1 or 2) and an extrapolatedly stretched outside of the first kelly bar. A kelly bar main body having at least a second kelly bar (2 or 3) and a plurality of boss blocks 7A (FIG. 5) respectively screwed to a lower outer peripheral surface of the first kelly bar 2 are provided. A split type boss 7 to be supported, and a plurality of cushioning members 8 attached to each boss block 7A and directly receiving the lower end face of the second kelly bar 3 are provided. The present invention is applied to a telescoping kelly bar device that sequentially transmits the rotation of the outermost kelly bar driven by the above to the inner kelly bar to rotate the excavation bucket. And each boss block 7
A on the upper inner peripheral surface side of A and the lower outer peripheral surface side of each cushioning material 8,
Key-shaped engaging portions 7a and 8a (FIGS. 5 and 6) that can be engaged with each other are provided, and the boss block 7A is attached to the second Kelly bar 3 in a state where the engaging portions 7a and 8a are engaged with each other. , Which solves the above problem. In particular, in the second embodiment, the projection 8b inserted into the drain hole HL formed in the split boss 7 is formed in the cushioning material 8.

[0009]

The engagement portion 8a provided on the lower outer peripheral surface of the cushioning material 8 is engaged with the engaging portion 7a provided on the upper inner peripheral surface of each boss block 7A. Second
To Keriba 3 Since the engaging portions 7a and 8a are in the form of a key, the cushioning material 8 does not come off from the boss block 7A after the boss block 7A is screwed. In particular, in the second aspect, the protrusion 8b of the cushioning material 8 is inserted into the drainage hole HL formed in the split boss 7, so that the rotation of the cushioning material 8 with respect to the boss 7 can be prevented.

[0010] In the means and means for solving the above problems which explain the constitution of the present invention, the drawings of the embodiments are used to make the present invention easy to understand. However, the present invention is not limited to this.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a longitudinal sectional view of a telescopic type kelever device according to the present invention, and FIGS. 2 to 4 are its II-II line, III-III line and IV-
FIG. 4 is a sectional view taken along line IV. The main body of the telescopic keliever device is formed by extrapolating a second kerivar 2 and an outer keriever 3 sequentially to an inner keliver 1 so as to be freely extendable.
Is formed by fitting and connecting a joint part 1b to a lower part of a pipe part 1a.

As shown in FIGS. 2 to 4, three torque transmitting keys 11 are attached to the outer peripheral surface of the pipe portion 1 a of the inner keriba 1 over substantially the entire length thereof, and a lower inner peripheral portion of the second keriba 2 is provided. A square groove 12 with which the key 11 meshes is formed on the surface. Although not shown,
The key 11 is also formed on the outer peripheral surface of the second kelly bar 2, and a square groove 12 that meshes with the key 11 is formed on the lower end of the inner peripheral surface of the outer kelly bar 3. When the outer keriba 3 is rotated by a rotation driving device (not shown), the rotation is transmitted to the second keriba 2 and the inner keriba 1 in order by the engagement between the key 11 and the square groove 12.

The upper end of the pipe portion 1a of the inner keriba 1 is connected to a wire rope suspended from a boom of an earth drill body (not shown) via a swivel joint,
As a result, the entire kelly bar device is hung on the boom. An excavation bucket (not shown) is connected to the end of the joint portion 1b, and the excavation bucket rotates with the rotation of the inner keelver 1.

An annular spring seat 4 is externally slidably inserted into the joint 1b.
And a spring seat 1 previously formed integrally with the joint portion 1b
The spring 5 for shock absorption is interposed between the spring 5 and the spring c. The second seat 2 and the split boss 7 attached to the outer peripheral surface of the second seat 2 are supported by the spring seat 4 via the cushioning material 6.
On the lower surface of the cushioning member 6, a step 6a corresponding to the step 4a formed on the upper surface of the spring seat 4 is formed, and both step portions 4a, 6a are formed.
The bolts are screwed into the step portions 4a and 4b from the side surfaces of the cushioning material 6 in a state in which the cushioning members 6 are aligned, whereby the cushioning material 6 is fixed to the spring seat 4. As the material of the cushioning material 6, a material that absorbs sound and is resistant to wear, for example, a nylon material containing molybdenum disulfide is used.

As shown in FIG. 5, the split boss 7 comprises six boss blocks 7A having arcuate inner and outer peripheral surfaces.
As shown in FIG. 4, each boss block 7 </ b> A is screwed to the outer peripheral surface of the second keriba 2 with a bolt 21. As shown in FIG. 5, a key-shaped engaging portion 7a is formed on the upper inner peripheral surface side of each boss block 7A, and an engaging portion 8a of a cushioning material 8 described later is engaged with the engaging portion 7a. You. In addition, each boss block 7
Steps 7b are formed at both ends of the upper portion of the boss A, and when the boss 7 is assembled, the boss blocks 7A are formed by the steps 7b.
A drain hole HL is formed therebetween. Further boss block 7
A is formed with four bolt through holes 7c from the outer peripheral surface to the inner peripheral surface.

As shown in FIGS. 2 and 6, the cushioning material 8 has an arc-shaped inner and outer peripheral surface, and one cushioning material 8 is attached to two boss blocks 7A of the split type boss 7. Can be As the material of the cushioning material 8, for example, a nylon material containing molybdenum disulfide or the like is used in the same manner as described above. A protrusion 8b as shown in FIG. 6 is formed at the center on the outer peripheral surface side of each cushioning material 8, and a key-shaped engaging portion corresponding to the engaging portion 7a of the boss block 7A is formed on both sides of the projecting portion 8b. 8a are formed respectively. The shape of the protruding portion 8b is the water drain hole H
The shape is substantially the same as the shape of L, and the length of one engaging portion 8a is substantially the same as the length of the engaging portion 7a of the boss block 7A.

The split boss 7 and the cushioning member 8 formed as described above are attached to the second keriba 2 as follows. First, the engaging portions 7a of the two boss blocks 7A are respectively engaged with the pair of engaging portions 8a of one cushioning material 8 as shown in FIG. 7, thereby forming a composite block as shown in FIG. At this time, the projection 8b of the cushioning material 8 is inserted into the drain hole HL formed between the boss blocks. Next, the inner peripheral surface of the composite block configured as described above is brought into contact with the outer peripheral surface of the second kelly bar 2, and the bolt through hole 7c of the boss block 7A communicates with the bolt hole 2a of the second kelly bar 2 (FIG. 4). Align.
In this state, the bolt 21 is inserted into the bolt through hole 7c as shown in FIG.
When the tip is screwed into the bolt hole 2a, a composite block including a pair of boss blocks 7A and one cushioning material 8 is fixed to the second kelly bar 2.

Subsequently, the other two composite blocks are attached to the outer peripheral surface of the lower part of the second keriba 2 in the same manner as described above.
As a result, the lower outer peripheral surface of the second kelly bar 2 is covered over the entire circumference with the split type boss 7 composed of the six boss blocks 7A, and three cushioning members 8 are annularly arranged on the upper portion thereof. After each boss block 7A is screwed onto the second keriba 2 in this way, the key-shaped engaging portions 7a, 8a do not come off, and the cushioning material 8 does not come off from the split boss 7. In addition, six drain holes HL are formed between the boss blocks 7A, three of which have the projections 8b of the buffer material 8 inserted therein, and the other three function as original drain holes. . Since the protrusion 8b of the cushioning member 8 is inserted into the drainage hole HL of the split boss 7 in this manner, the cushioning member 8 does not rotate undesirably with respect to the split boss 7. The operation at the time of excavation and the functions of the cushioning members 6 and 8 are the same as those described in the related art, and the description is omitted here.

As described above, in the present embodiment, the cushioning member 8 can be undetachably attached to the split boss 7 without using bolts as in the prior art, so that the operation of attaching the cushioning member 8 is facilitated. In addition, the contact area between the cushioning member 8 and the lower surface of the outer kelly bar 3 is sufficient to reduce the surface pressure, the settling of the cushioning member 8 can be minimized, and the frequency of replacement of the cushioning member 8 can be reduced. Further, it is possible to prevent the cushion material from coming off due to the breakage of the bolt. Also, since the bolts are not exposed on the upper surface of the cushioning member 6 attached to the spring seat 4 as well, a sufficient contact area between the cushioning member 6 and the lower surfaces of the second keriba 2 and the split boss 7 is sufficient as described above. The pressure can be reduced, and sag of the cushioning material 6 can be suppressed. Here, in the above-described embodiment, the second keriba is constituted by the second keriba 2 and the outer keriba 3 is constituted by the second keriba.

Although the protrusion 8b of the buffer member 8 is inserted into the drain hole HL of the split boss 7 to prevent the rotation of the buffer member 8, the rotation preventing mechanism is not limited to this. Further, in the above-described embodiment, an example in which three cushioning members are attached to six boss blocks has been described. However, the number of these members is not limited to the embodiment. A configuration in which three or more cushioning members are attached may be used. Furthermore, an example in which three inner, second and outer kelivers are provided has been described, but the present invention can also be applied to a kellyba apparatus in which four or more kelivers are provided so as to be able to expand and contract with each other. In this case, the kelly bar on which the split boss is extrapolated forms the first kelly bar, and the kelly bar placed on the split boss forms the second kelly bar. Furthermore,
Although the description has been made with respect to the round-shaped keriba, the present invention can be similarly applied to the square-shaped keriba.

[0021]

According to the present invention, the key-shaped engaging portions are provided on the upper inner peripheral surface side of the boss block and the lower outer peripheral surface side of the cushioning material, and the boss block is engaged with the engaging portions. Is screwed to the second keriba, so that the cushioning material can be undetachably attached to the split boss without using bolts as in the conventional case. Therefore, the work of mounting the cushioning material is facilitated, and the contact pressure between the cushioning material and the first kelever can be sufficiently reduced to reduce the surface pressure, thereby reducing the settling of the cushioning material and reducing the frequency of replacement. It is possible to do. Further, it is possible to prevent inconveniences such as breakage of the bolt and detachment of the buffer. In particular, according to the second aspect of the present invention, since the projection is inserted into the drainage hole formed in the split boss on the buffer material, it is possible to prevent the buffer material from rotating undesirably with respect to the split boss.

[Brief description of the drawings]

FIG. 1 is a vertical cross-sectional view of a telescopic Keriva apparatus according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line II-II of FIG.

FIG. 3 is a sectional view taken along line III-III of FIG. 1;

FIG. 4 is a sectional view taken along line IV-IV of FIG. 1;

FIG. 5 is a perspective view showing a boss block of the split boss.

FIG. 6 is a perspective view showing a cushioning material.

FIG. 7 is a diagram showing an engagement state between a boss block and a cushioning material.

FIG. 8 is a perspective view showing a composite block in which one cushioning material and two boss blocks are combined.

FIG. 9 is a vertical cross-sectional view showing a conventional telescopic type kelever device.

FIG. 10 is a longitudinal sectional view showing another conventional example.

11A is a sectional view taken along line aa of FIG. 10, and FIG. 11B is a sectional view taken along line bb of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Inner keriba 2 Second keriba 3 Outer keriba 4 Spring seat 5 Impact buffer spring 6,8 Buffer material 7 Split type boss 7A Boss block 7a Engagement part 7b Projection part 8a Engagement part 8b Step 8c Bolt through hole 11 Key 12 Square groove 21 volts

Claims (2)

(57) [Claims] 1. A kerry bar body having at least a first kelly bar and a second kelly bar externally extended and retractably attached to the first kelly bar, and each of which is screwed to a lower outer peripheral surface of the first kelly bar. A split-type boss comprising a plurality of boss blocks and supporting the second kelly bar; and a plurality of cushioning members attached to each of the boss blocks and directly receiving a lower end surface of the second kelly bar. In the telescopic kelly bar device, which connects the digging bucket to the keriba and sequentially transmits the rotation of the outermost keriba driven by the driving means to the inner keriba to rotate the digging bucket, the upper part of each of the boss blocks Key-shaped engaging portions that can be engaged with each other are provided on the inner peripheral surface side and the lower outer peripheral surface side of each of the cushioning members, and these engaging portions are engaged with each other. Telescopic Keriba device has been the boss block state is characterized by being screwed into the second Keriba. 2. The telescopic kelly bar device according to claim 1, wherein the cushioning material has a projection inserted into a drain hole formed in the split boss.