JP2002180466A - Chucking device for buried column member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To clamp the outer peripheral surface of a column member with a uniform force by means of a very simple structure without separately providing a large-scale actuator exclusively for clamping. SOLUTION: A casing 17 which is held by a hydraulic cylinder 16 is provided with a pressing cam surface 19 facing the center of clamping and titled outwardly and divergently in the direction in which thrust is imparted. A plurality of chuck pawls 20 for clamping the outer peripheral surface of the column member 11 are each provided with a clamping surface 23 which abuts against the outer peripheral surface of the column member 11 and a cam receiving surface 21 which is tilted by the same angle as the pressing cam surface 19 of the casing 17 and slidably abuts against the cam surface 19. The chuck pawls 20 are held against the casing 17 in such a way as to be movable along the cam surface 19. The thrust transmitted from the hydraulic cylinder 16 to the casing 17 acts as a component of force going radially inwards toward the chuck pawl 20 through the portion of contact between the cam surface 19 and the cam receiving surface 21 and the column member 11 is clamped by the component of force.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for press-fitting a column made of concrete, steel pipe or the like, a column made of cylindrical pipe for excavation, etc. into the ground, or for pulling out the column from the ground. The present invention relates to a chucking device for an underground pillar material to be buried.

[0002]

2. Description of the Related Art At construction sites and civil engineering sites, a method of pressing a pile into the ground using a large hydraulic cylinder or the like has been adopted instead of the conventional pile driving. This method does not cause the problem of vibration noise compared to pile driving, and is considered to be the mainstream method in the future.

[0003] When this press-fitting method is used, thrust is applied to the head of the pile. However, when thrust is applied to the head of the pile, the entire equipment may become large. A method is employed in which the outer peripheral surface of a pile is gripped by a chucking device and thrust is applied to the pile through the chucking device.

As a chucking device, for example, a device as shown in FIGS. 17 and 18 has been used.

The chucking device 1 is supported on a base 2 fixedly installed on the ground by a weight or the like (not shown) via a hydraulic cylinder 3 which is a thrust applying means, and has shafts 4a, 4b, 4c. A plurality of arc-shaped gripping arms 5a to 5d pivotally connected to each other, and a tightening band 6 disposed around the periphery of these gripping arms 5a to 5d;
It has a schematic configuration including a tightening cylinder 7 that pulls both ends of the tightening band 6 to narrow the entire circumference of the gripping arms 5a to 4d.

When the chucking apparatus 1 is used, the pile 8 is inserted and set inside the gripping arms 5a to 5d in a state where the gripping arms 5a to 5d are spread, and the clamping band 6 is pulled by the clamping cylinder 6 to grasp the arm. The outer circumference of the pile 8 is gripped by the gripping arms 5a to 5d by reducing the entire circumference of the arms 5a to 5d. When press-fitting the pile 8, the hydraulic cylinder 3, which is a thrust applying means, is operated in this state to displace the pile 8 together with the chucking device 1 downward (underground direction).

The chucking device 1 is used not only at the time of press-fitting the pile 8 but also at the time of pulling-out of the pile or at the time of press-fitting and pulling-out of a column material other than the pile.

[0008]

However, in the case of the conventional chucking device 1, a dedicated large-sized tightening cylinder 7 must be provided in order to reduce the entire circumference of the gripping arms 5a to 5d during chucking. Therefore, there is a problem that the whole apparatus becomes large and heavy, the structure becomes complicated, and the manufacturing cost rises.

Further, in the conventional chucking device 1, since a plurality of gripping arms 5a to 5d are hingedly connected by the shafts 4a to 4c, the outer peripheral side of the pillar member such as the pile 8 is located. It is difficult to apply a uniform pressing force from the large, and a large load acts on a part of the outer periphery of the column material,
The outer peripheral surface of the column is likely to be deformed or damaged. In particular, the deformation of the column material due to the variation in the pressing force tends to occur when the column material is a pipe material such as a steel pipe.

Accordingly, the present invention provides an extremely simple structure capable of gripping the outer peripheral surface of a column member with an equal force without separately providing a large-scale dedicated actuator, thereby reducing the size and weight of the apparatus. , To reduce manufacturing costs,
Moreover, it is an object of the present invention to provide a chucking device for an underground buried pillar which can eliminate deformation and breakage of the pillar to be gripped.

[0011]

Means for Solving the Problems As means for solving the above-mentioned problems, the invention according to claim 1 is a substantially cylindrical shape which is held by a thrust applying means and into which a pillar is inserted and set. A casing, a plurality of chuck claws that are disposed inside the casing and grip an outer peripheral surface of a column material inserted and set in the casing, and a chucking device for an underground pillar material having an underground burial, The casing has a pressing cam surface facing the gripping center side and inclined outwardly in the thrust applying direction, while the chucking pawl has a gripping surface that abuts against an outer peripheral surface of a pillar material; And a cam receiving surface that is inclined at the same angle as the pressing cam surface and slidably abuts the pressing cam surface.
The casing is movably held along the pressing cam surface.

In the case of this invention, when the column is inserted into the casing and a thrust along the axial direction of the column is applied to the housing by the thrust applying means in this state, the thrust passes through the pressing cam surface of the housing to each chuck claw. At this time, a component force toward the inside in the radial direction and a component force along the thrust applying direction act on each chuck claw. Here, until the chuck pawl completely engages between the column member and the pressing cam surface, the chuck pawl moves radially inward while sliding the pressing cam surface and the cam receiving surface. Then, when the chuck pawl completely engages between the column member and the pressing cam surface, the gripping surface is firmly pressed against the column member by a component force directed inward in the radial direction. At this time, the component force acting on the gripping surface of each chuck claw is a uniform force determined by the inclination angle between the pressing cam surface and the cam receiving surface.

[0013] According to a second aspect of the present invention, the casing includes:
An initial load applying means for bringing the cam receiving surface of the chuck pawl into contact with the pressing cam surface is provided.

In the case of the present invention, since the contact between the pressing cam surface and the cam receiving surface is maintained by the initial load applying means, the chuck pawl is completely held until the chuck pawl is completely engaged between the column member and the pressing cam surface. Moves smoothly along the pressing cam surface.

According to a third aspect of the present invention, the initial load applying means is constituted by a spring for urging the chuck pawl toward the pressing cam surface of the casing. Was constituted by a hydraulic cylinder that displaces the chuck claw with respect to the casing in the thrust applying direction.

When the initial load applying means is constituted by a spring, the structure itself is simplified, and when the initial load applying means is constituted by a hydraulic cylinder, the chuck pawl can be accurately moved over a long stroke.

According to a fifth aspect of the present invention, the cam receiving surface of the chuck pawl is formed longer than the pressing cam surface, and the contact position of the chuck pawl against the pressing cam surface is maintained between the chuck pawl and the casing. A guide structure is provided.

In the present invention, since the cam receiving surface of the chuck pawl can be brought into contact with the pressing cam surface for a long stroke, the movable width of the chuck pawl in the radial direction can be increased. In addition, when the chuck pawl contacts the pressing cam surface near the end of the cam receiving surface, the pressing force of the pressing cam surface may act to break the posture of the chuck pawl. The posture is kept constant.

According to a sixth aspect of the present invention, the chuck pawl is
The structure includes a claw main body having a cam receiving surface and a separate shoe having a gripping surface for the column material, and the shoe is replaceably attached to the claw main body.

In the case of the present invention, it is possible to easily cope with a column material having a different inclination of the outer peripheral surface by replacing only the shoes.

[0021]

Next, embodiments of the present invention will be described with reference to the drawings.

First, a first embodiment shown in FIGS. 1 to 6 will be described.

FIGS. 2 and 3 show an example of a press-fitting facility for a column material 11 for underground burial employing the chucking device 10 according to the present invention. In FIG. A base frame 14 fixedly installed on the ground is a base plate attached to the base frame 12.

The base plate 14 is formed with a through hole 15 into which the pillar 11 is inserted.
5, a plurality of hydraulic cylinders 1 as thrust applying means
6 is installed in an inverted state. A casing 17 of the chucking device 10 according to the present invention is supported and fixed above the plurality of hydraulic cylinders 16 as shown in FIG.

The casing 17 is formed in a substantially cylindrical shape, and has an annular concave portion 18 as shown in FIG.
A pressing cam surface 19 is formed in the concave portion 18 and faces the gripping center side and is inclined outwardly in the thrust applying direction (the direction of arrow F). In this embodiment,
The pressing cam surface 19 is formed over the entire inner peripheral area of the concave portion of the casing 17 and has a conical inner surface shape as a whole.

The concave portion 18 accommodates three arc-shaped chuck claws 20. This chuck claw 20
As shown in FIG. 5, each of the chuck claws 20 has a pressing cam surface 1 of a casing 17 as shown in FIGS.
A cam receiving surface 21 is formed which has the same inclination angle as 9 and slidably abuts against the pressing cam surface 19. A gripping surface 23 having a plurality of corrugated irregularities is formed on the inner peripheral surface side of each chuck claw 20.
To come into contact with the outer peripheral surface.

On the other hand, a guide rod 24 is screwed to the lower end of the casing 17, and a spring 25, which is an initial load applying means, is supported on the guide rod 24 and a bracket urged upward by the spring 25. 26 is supported so as to be able to move up and down. Bracket 2
Numeral 6 is formed so as to be bent in a substantially L-shaped section, and the lower surface of each of the chuck claws 20 is slidably supported on the upper end surface thereof. Therefore, each chuck claw 20 is spring-biased upward through the bracket 26, and thereby the cam receiving surface 21 and the pressing cam surface 19 are maintained in a contact state.

In the above configuration, when the column 11 is pressed into the ground using this facility, the column 11 is first inserted into the substantially cylindrical casing 17 from above the chucking device 10. Then, the column material 11 is set at a predetermined gripping position. At this time, each chuck claw 20 is urged by the spring 25 to be displaced radially inward along the pressing cam surface 19 of the casing 17.
When the outer peripheral surface of the column material 11 comes into contact with the gripping surface 23 and is inserted into the inside, each chuck claw 20 is displaced in the radially expanding direction against the force of the spring 25 due to the frictional resistance at this time. Therefore, when the pillar 11 is inserted, the diameter of each of the chuck claws 20 is automatically increased, and the smooth insertion of the pillar 11 is allowed.

Next, when the hydraulic cylinder 16 serving as the thrust applying means descends from this state, a downward thrust F is transmitted to the casing 17 of the chucking device 10, and this thrust F is transmitted to the pressing cam surface 19 and the cam receiving surface. 21 and the component force F _r directed radially inward through the contact portion of, acting on the chuck jaws 20 as a component force F _s along the thrust-imparting direction. In this case the chuck jaws 20 receives the component force F _r directed radially inward, until caught completely between the outer peripheral surface and the pressure cam surface 19 of the pillar 11, so as to follow the pressing cam surface 19 Moves radially inward.

[0030] Then, the chuck claws 20 bites completely between pillar 11 and the pressing cam surface 19, the outer peripheral surface of the gripping surface 23 pillar 11 of the chuck claws 20 by the component force F _r toward the radially inner side firmly pressed against the with it the component force F _s along the thrust-imparting direction is transmitted to the pillar member 11 through the chuck claws 20. Therefore, at this time, the pillar 11 operates integrally with the casing 17 of the chucking device 10,
Upon receiving the thrust, it is pressed into the ground for a specified stroke.

When the hydraulic cylinder 16 lowers by the specified stroke in this way, the hydraulic cylinder 16 then rises again, returning the casing 17 of the chucking device 10 to the initial position, and the same repetitive operation is repeated thereafter. still,
When the hydraulic cylinder 16 is raised, the chuck jaws 20 are automatically expanded by receiving the contact resistance with the column material 11 in the same manner as when the column material 11 is first inserted into the casing 17. The raising operation of the casing 17 to the grip position is allowed.

The chucking device 10 according to this embodiment includes:
As described above, since each chuck claw 20 functions as a wedge through the contact portion between the pressing cam surface 19 and the cam receiving surface 21, it is possible to securely grip the column member 11 without providing a special actuator for providing gripping force. can be, moreover, a component force F _r of the radial direction acting on the chuck jaws 20 is pressing cam face 1
9 and the inclination angle θ of the cam receiving surface 21, the gripping force of all the chuck claws 20 can be made uniform.
Therefore, when the column material 11 is gripped, a large load does not act on a part of the outer peripheral surface of the column material 11 in a biased manner, and it is possible to reliably prevent the deformation and breakage of the column material 11 at the time of gripping. it can.

In the above description, an example was described in which the base plate 14 on which the chucking device 10 was installed and the base frame 12 were fixed on the ground by weights 13. However, the present invention is not limited to this. As shown in FIG. 8, the anchor may be fixed by anchor posts 27 buried underground.

Next, a second embodiment shown in FIGS. 9 to 16 will be described.

FIGS. 9 and 10 show the entire structure of a press-fitting facility employing the chucking device 30 according to the present invention.
And the base frame 12
A casing 31 of the chucking device 30 is mounted and supported at a substantially central portion of the casing 30 via a pair of hydraulic cylinders 16 serving as thrust applying means.

As shown in FIG. 11, the casing 31 has an overall shape in which an annular upper wall and a lower wall are attached to the upper and lower sides of a cylindrical body. A guide mechanism 33 connected to the cylinder 16 and engaged with the bracket 32 as shown in FIG.
Is to be guided up and down.

The casing 31 is formed longer in the axial direction than that of the first embodiment, and
A plurality of pressing cam surfaces 34 are provided at equal intervals in the circumferential direction on the inner peripheral surface of the upper wall. Specifically, a plurality of guide grooves 36 each having a substantially rectangular cross section having a constricted wall 35 (see FIG. 13) at the opening are formed on the inner peripheral surface of the upper wall, and the bottom surface of each guide groove 36 is pressed. A cam surface 34 is provided. Each pressing cam surface 34 faces the gripping center side and is inclined so as to open outward in the thrust applying direction (the direction of arrow F in FIG. 11).

A chuck claw 37 is slidably fitted in each guide groove 36 as shown in FIGS. As shown in FIGS. 11 and 14, each of the chuck claws 37 has a claw main body 3 formed in a substantially right-angled triangular shape in side view.
8 and a shoe 39 screwed to a surface of the claw body 38 along the vertical direction.
Is a cam receiving surface 40 whose oblique side has the same inclination angle as the pressing cam surface 34.
It has been. The surface of the shoe 39 facing the gripping center side is a gripping surface 42 in contact with the outer peripheral surface of the column 41, and the gripping surface 42 is formed with a cross section curved in an arc shape as shown in FIG. At the same time, corrugated irregularities are formed in the longitudinal direction.

In this example, since a pillar 41 such as a utility pole whose outer diameter continuously changes is handled, as shown in FIG. 14, the gripping surface 42 of the shoe 39 has a small angle α toward the upper side. It only opens and slopes.

The oblique side of the claw body 38 is a caning 3
It is formed sufficiently longer than one guide groove 36 and is slidably fitted in the guide groove 36. A restricting groove 44 is formed on a side edge of the claw body 38 along the cam receiving surface 40, and the constricted wall 35 (see FIG. 13) on the guide groove 36 side is fitted into the restricting groove 44. Therefore, in the case of this embodiment, when the guide groove 36 including the constricted wall 35 and the oblique side portion of the claw body 38 including the restriction groove 44 are fitted, the contact posture between the pressing cam surface 34 and the cam receiving surface 40. Are always kept constant, and these portions constitute the guide structure in the present invention.

On the other hand, on the lower wall of the casing 31, FIG.
As shown in FIG. 1, a plurality of hydraulic cylinders 45 are provided as initial load applying means, and a ring-shaped bracket 46 is attached to an upper end of the hydraulic cylinder 45. The ring-shaped bracket 46 has a cylindrical portion 47 that is slidably fitted to the inner peripheral surface of the casing 31, and the claw main bodies 38 of the chuck claws 37 are slidably mounted on the upper surface thereof. ing.

When press-fitting the column material 41 tapered downward in the downward direction by using this equipment, the column material is inserted into the casing 31 with the hydraulic cylinder 45 of the chucking device 30 lowered. After the insertion of the column 41 and the insertion of the column member 41 by the set amount, the hydraulic cylinder 45 is raised to such a height that the gripping surface 42 of each chuck claw 37 slightly contacts the outer peripheral surface of the column member 41. At this time, each chuck pawl 37 is pressed by the cam receiving surface 40 on the pressing cam surface 34 of the casing 31.
The claw 37 moves along the pressing cam surface 34 in the gripping center direction (radially inward).

At the beginning of the press-in operation of the column member 41, since the diameter of the holding position of the column member 41 is small as shown in the right half of FIGS. 11 and 12 and FIG. And the amount of displacement of each chuck claw 37 in the gripping center direction also increases.

Next, from this state, the thrust applying means oil
The pressure cylinder 16 is lowered, and
When the thrust F in the direction is given, the thrust F is applied to the pressing cam surface 3.
4 through the contact portion between the cam receiving surface 40 and each chuck pawl 37.
Component F toward the inside in the radial direction _rAnd along the thrust application direction
Component F_sAt this time, each chuck claw 37
Until it completely bites between the column member 41 and the pressing cam surface 34
During this, it moves radially inward along the pressing cam surface 34. So
Then, when each chuck claw 37 is completely engaged, the chuck
Component force F in which gripping surface 42 of claw 37 is directed radially inward_rBy
Therefore, the column 41 is firmly gripped, and the column 41 is
Downward component force F applied to chuck jaw 37_sUnderground by
Pressed into.

Here, while the diameter of the column member 41 is small, FIG.
As shown in the right half of FIG.
However, in this embodiment, since the contact posture between the pressing cam surface 34 and the cam receiving surface 40 is regulated by the above-described guide structure, the grip surface 42 of the chuck pawl 37 is in a stable posture. The column 41 can be abutted, and as a result, the column 41 can be firmly gripped.

After the hydraulic cylinder 16 has been lowered by the prescribed stroke, the hydraulic cylinder 16 is raised again to the initial position while the hydraulic cylinder 45 in the casing 31 is lowered. At this time, each chuck claw 37 descends relatively to the casing 31, and the gripping surface 42 is separated from the outer peripheral surface of the column 41.

Thereafter, the holding and press-fitting of the column material 41 are repeatedly performed in the same manner as described above.
Since the gripping diameter of the column member 41 increases with this, each chuck claw 37 is, as shown in the left half of FIGS.
The outer peripheral surface of the column member 41 is gripped at a position gradually lowered with respect to the pressing cam surface 34 of the casing 31. However, this does not cause any problem in terms of gripping force with respect to the column member 41, and the gripping can be similarly firmly performed from the small diameter portion on the lower side to the large diameter portion on the upper side.

Further, the chucking device 3 of this embodiment
0 indicates that each of the chuck claws 3 is the same as in the first embodiment.
Although the outer peripheral surface of the column member 41 can be stably gripped with a uniform force by the wedge effect of No. 7, since the width per one chuck jaw 37 is narrow and the length in the vertical direction is set long,
It is possible to flexibly cope with a wide range of changes in the diameter of the column 41, to avoid an increase in the contact surface pressure on the column 41, and to further reduce the possibility of deformation or breakage of the column 41.

Further, in the chucking device 30 of this embodiment, the chuck pawls 37 are separately formed on the pawl main body 38 on which the cam receiving surface 45 is formed and the shoe 39 on which the gripping surface 40 is formed. Since the connection is made by screwing, it is only necessary to replace only the shoe 39 when replacing the component when the gripping surface 40 is worn out or when press-fitting the column 41 having a different inclination of the outer peripheral surface. it can. Therefore, the single chucking device 30 can be applied to press-fitting of various types of pillars 41 having different specifications, etc., so that the device can be used efficiently and maintenance can be easily performed. It can be done at low cost.

In the above description, an example was described in which the chucking device according to the present invention was used for press-fitting a pillar. However, by using the chucking device upside down,
It can also be used for pulling out column materials.

[0051]

As described above, according to the present invention, part of the thrust of the thrust applying means is reduced by the action of the pressing cam surface of the housing and the cam receiving surface of the chuck claw in the radially inward direction of each chuck claw. After the conversion, the outer peripheral surface of the pillar can be gripped by the pressing force. Therefore, it is not necessary to separately provide a large-scale dedicated actuator for gripping the pillar, and the entire apparatus is reduced in size and weight. And a reduction in manufacturing cost.

Further, according to the present invention, since the pressing force of each chuck claw against the column material can be applied as a uniform component force by the function of the pressing cam surface and the cam receiving surface, an excessive force is applied to a part of the column material. The load does not act unevenly, and therefore, deformation, breakage, and the like of the pillar material to be gripped can be reliably prevented.

According to the second aspect of the present invention, since the initial load applying means is further provided, the chuck pawl is held on the pressing cam surface until the chuck pawl is completely engaged between the column member and the pressing cam surface. The chucking operation can be performed more smoothly along with the chucking operation.

According to the third aspect of the present invention, since the initial load applying means is constituted by a spring, there is an advantage that the structure can be simplified and the production at lower cost can be realized, and the fourth aspect of the present invention. Since the initial load applying means is constituted by a hydraulic cylinder so that the chuck pawl can be accurately moved for a long stroke, a column member whose outer diameter changes greatly in the axial direction, or a plurality of column members whose outer diameters differ greatly There is an advantage that it can easily cope with the column material.

According to a fifth aspect of the present invention, the length of the cam receiving surface of the chuck pawl can be made sufficiently long by maintaining the contact position of the chuck pawl against the pressing cam surface by the guide mechanism. Thus, the outer diameter width of the column material that can be gripped by the chuck claws can be further increased.

According to the sixth aspect of the present invention, it is possible to cope with various pillars only by exchanging shoes, so that the apparatus can be used efficiently. Further, since only the shoe can be replaced, it is advantageous in terms of maintenance.

[Brief description of the drawings]

FIG. 1 is an enlarged sectional view of a main part of FIG. 3 showing a first embodiment of the present invention.

FIG. 2 is a plan view showing the embodiment.

FIG. 3 is an exemplary sectional view taken along the line AA of FIG. 2 showing the embodiment;

FIG. 4 is an enlarged view of a main part of FIG. 2 showing the same embodiment.

FIG. 5 is an exemplary plan view of the shoe showing the embodiment;

FIG. 6 is an exemplary sectional view of the same embodiment taken along line BB of FIG. 5;

FIG. 7 is an exemplary plan view showing a modification of the embodiment;

FIG. 8 is a sectional view taken along the line CC of FIG. 7 showing the modification.

FIG. 9 is a plan view showing a second embodiment of the present invention.

FIG. 10 is a side view showing the same embodiment.

FIG. 11 is an enlarged cross-sectional view of the same embodiment, taken along the line DD in FIG. 9;

FIG. 12 is a plan view of FIG. 11 showing the same embodiment.

FIG. 13 is a sectional view of the same embodiment, taken along line EE of FIG. 11;

FIG. 14 is a partially cutaway side view of the chuck pawl showing the same embodiment.

FIG. 15 is a view of the same embodiment as viewed in the direction of arrow F in FIG. 14;

FIG. 16 is a view of the same embodiment as viewed in the direction of the arrow G in FIG. 14;

FIG. 17 is a plan view showing a conventional technique.

FIG. 18 is a side view showing the same technique.

[Explanation of symbols]

 10, 30 chucking device 11, 41 pillar member 16 hydraulic cylinder (thrust applying means) 17, 31 casing 19, 34 pressing cam surface 20, 37 chuck chuck 21, 40 cam receiving surface 23, 42 ... Grip surface 25 ... Spring (initial load applying means) 38 ... Claw body 39 ... Shoe 45 ... Hydraulic cylinder (Thrust applying means)

Claims (6)

[Claims] 1. A substantially cylindrical casing which is held by a thrust applying means and into which a pillar is inserted and set, and an outer peripheral surface of the pillar which is disposed inside the casing and inserted and set in the casing A plurality of chuck claws for gripping the underground column material for underground burying, comprising: a pressing unit that faces the holding center side of the casing, and is inclined to open outward in a thrust applying direction. While providing a cam surface, a gripping surface that contacts the outer peripheral surface of the column material,
A cam receiving surface that is inclined at the same angle as the pressing cam surface of the casing and slidably contacts the pressing cam surface is provided, and the chuck claw is held by the casing so as to be movable along the pressing cam surface. A chucking device for underground buried pillars. 2. The chucking device for underground buried pillars according to claim 1, wherein the casing is provided with initial load applying means for bringing the cam receiving surface of the chuck pawl into contact with the pressing cam surface. 3. The chucking device for underground buried pillars according to claim 2, wherein the initial load applying means is a spring that urges the chuck pawl toward the pressing cam surface of the casing. 4. The chucking method for an underground pillar according to claim 2, wherein the initial load applying means is a hydraulic cylinder for displacing the chuck pawl relative to the casing in a thrust applying direction. apparatus. 5. A guide structure in which a cam receiving surface of a chuck claw is formed longer than a pressing cam surface, and a guide structure is provided between the chuck claw and a casing to maintain a constant contact posture of the chuck claw with the pressing cam surface. The chucking device for a column material for underground burial according to any one of claims 1 to 4, characterized in that: 6. A chuck comprising: a claw main body having a cam receiving surface; and a separate shoe having a gripping surface for a column member, wherein the shoe is replaceably attached to the claw main body. The chucking device for a column material for underground burial according to claim 1.