JP2001269926A - Drilling machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a small and a compact drilling machine which can be appropriately used in order to lay down a post driving anchor on a concrete ceiling face. SOLUTION: A drill feed mechanism 3 is installed in an extensible support 2, coaxially, and a boring drill 4 is fed out by the drill feed mechanism 3. The boring drill 4 is also disposed coaxially with the support 2. A reaction force developed when the boring drill 4 drills a boring surface 12 is applied to the support 2, vertically, and is transmitted to a support surface 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for piercing concrete or the like, and more particularly to a piercing device which can be suitably used for providing an anchor hole in a ceiling surface of a building or the like after casting concrete.

[0002]

2. Description of the Related Art Generally, in order to lay a post-fixed anchor on a concrete ceiling surface, first, a hole having a diameter and a depth corresponding to the size of an anchor such as a stud bolt is drilled vertically in the ceiling surface. Next, a method of driving a metal material into a gap between the inserted anchor and the hole or filling a solidifying agent and curing the material is adopted. 2. Description of the Related Art Conventionally, when piercing a ceiling made of concrete, a temporary scaffold is set at a height at which an operator's hand can reach the ceiling, and a hole is drilled using the scaffold. In this case, the operator will support the gravity applied to the drill,
It is necessary to work while maintaining the upward feeding force of the drill, and also to the continuous intense vibration transmitted to the drill due to drilling, or the biting reaction force generated suddenly in the rotation direction of the drill. I have to endure. In addition, the work environment is the worst, because the work is performed on a scaffold at a high place, and intense noise and dust are generated at a short distance overhead.
Therefore, for example, when drilling a hole of about 20 mm,
About five people a day are the best.

In order to improve such a primitive drilling operation, the applicant of the present invention has a telescopic strut which is temporarily and rigidly set by first extending a telescopic upper end to a ceiling surface and a lower end to a floor surface. And a ceiling-only rear hitting anchor device provided with a feed mechanism attached to the support and a drill drill attached to and sent from the feed mechanism (Japanese Patent Laid-Open No. Hei 11-1999).
-262914). According to the above device, the column is temporarily and rigidly set between the ceiling surface and the floor surface, and the drilling drill is rotationally driven and is continuously fed upward by the feed mechanism, thereby achieving high efficiency on the ceiling surface. This has an effect that a hole having a relatively large diameter can be formed.

[0004]

However, in the device specifically described in the above publication, since a drill is attached to a feed mechanism provided to project from the side of the column, the drill is generated. The reaction force is transmitted from the lateral direction to the column, whereby a bending stress is generated in the column. Therefore, the columns are required to have structural strength and dimensions in consideration of the bending stress. Therefore, an object of the present invention is to improve such a problem, and to provide a perforation device that is configured so as not to generate bending stress on a column and that can be reduced in size and weight with a simpler structure while maintaining high efficiency. It is intended to provide.

[0005]

According to the first aspect of the present invention, there is provided a telescopic strut, a drill feed mechanism provided on the axis of the strut, and a drilling hole arranged on the axis of the strut. A drilling device comprising a drill, wherein the drilling drill is configured to be coaxially movable with respect to a column by a drill feed mechanism. In the above-described drilling device, the drill feed mechanism is provided on the axis of the column, and the drill is arranged on the axis of the column.For example, when drilling on a concrete ceiling surface, the reaction force of the drill is Directly transmitted along the axis to a support surface such as a floor.
Therefore, no bending stress is generated in the column, and its structural strength and dimensions can be designed to be small. In addition, since the drill feed mechanism and the drill do not protrude significantly in the lateral direction of the column, the entire drilling device can be made compact.

According to a second aspect of the present invention, in the above-mentioned drilling apparatus, a drill feed mechanism is provided in the column so as to be coaxially slidable on the column, and is provided in the column to drive the column in the axial direction. It has a drive part, and a drill is connected to the connection body. According to such a drill feed mechanism, the structure is simplified, and it can be easily provided on the axis of the column.

According to a third aspect of the present invention, in the above-described drilling device, the connecting body in the drill feed mechanism is driven in the axial direction by a driving unit via a compression spring. With this configuration, the compression spring effectively absorbs the difference between the unevenness of the drilling speed and the constant feed speed by the drill feed mechanism, so that a reasonable and smooth drilling operation can be performed. In addition, since the compression spring absorbs the vibration from the drill, the vibration generated by the drilling can be prevented from being directly transmitted to the support, and the magnitude of the reaction force from the support to the support surface such as the floor is constant. The following can be suppressed. Prior to the start of drilling, the drill tip is aligned with the drilling position while the drill is pressed slightly downward against the compression spring, and then the drill is returned to its original position. In addition to this, the support can be set upright at a predetermined position.

According to a fourth aspect of the present invention, in the drilling device, a compression spring in the drill feed mechanism is housed in a cylindrically formed coupling body, and a lifting / lowering nut member is screwed onto a long bolt that is rotationally driven by a driving unit. The lifting nut member compresses the compression spring by the rotation of the long bolt, so that the connecting body slides coaxially with the support. By configuring the drill feed mechanism in this way, the structure can be simplified and the whole apparatus can be made more compact.

According to a fifth aspect of the present invention, in the drilling apparatus, the lifting nut member in the drill feed mechanism is a split nut composed of a plurality of divided pieces, and moving means for moving each divided piece in the radial direction is provided. Further, the screwing of the lifting nut member to the long bolt can be released by the moving means. With this configuration, after the drilling, the screwing of the lifting nut member is released and the compression spring is returned to the state before the compression, and the drill is pushed down, so that the drill is more easily extracted from the drilled hole. be able to.

According to a sixth aspect of the present invention, in any one of the above-described drilling devices, a grip portion for gripping is provided on the column, and a drive switch for the drilling drill and a drive switch for the drill feed mechanism are provided on the grip portion. It is characterized by the following. When such a grip portion is provided, the drilling drill and the drill feed mechanism can be started, for example, in a state where the grip portion is gripped by hand and the column is stably stood. In addition, a stable punching operation can be performed by firmly grasping the grip portion with both hands during the punching operation. Further, the grip portion can be easily moved by grasping with one hand. According to a seventh aspect of the present invention, in any one of the above-described drilling apparatuses, the drill feed mechanism is a dust-proof type. With such a dustproof type, it is possible to prevent dust generated at the time of drilling from entering the drill feed mechanism.

The invention according to claim 8 is the perforation apparatus according to any one of the above, wherein a vibration isolator is provided at the bottom of the column, and the vibration isolator includes a flexible vibration isolating layer in contact with the support surface of the column, and a harder layer than that. It has a two-layer structure of a hard vibration isolating layer. By providing such a vibration isolator,
In addition to suppressing the transmission of vibration generated by drilling to the support surface such as the floor, for example, when drilling the anchor hole diagonally avoiding the buried reinforcing bar in the ceiling, the support columns should be installed diagonally accordingly. Also, the strut can be stably supported on the supporting surface by the action of the flexible vibration isolating layer. According to a ninth aspect of the present invention, in any one of the perforating apparatuses,
The strut is formed in a cylindrical shape, and a driving wire made of a spiral cable is inserted into the strut. With this configuration, the driving wires are housed in the support pillars to improve the operability and appearance of the device, and the use of the spiral cable makes it difficult for the internal cable to be damaged even if the device is repeatedly expanded and contracted. Properties can be further improved.

[0012]

Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a front view showing an example of the punching device of the present invention. The drilling device 1 includes a telescopic column 2, a drill feed mechanism 3 provided on the axis of the column 2, and a drill 4 arranged on the axis of the column 2. The drill 4 is a commercially available electric drill.
The column 2 has an outer cylinder 5 and an inner cylinder 6 that slide with respect to each other.
00 is attached, and a vibration isolator 7 also serving as a non-slip is provided at the bottom. A power cable 101 is extended from the control unit 100, and a plug provided at the end thereof is connected to a power supply unit (not shown) such as an outlet. Lower ends of a pair of U-shaped grip portions 8 are respectively fixed to upper portions of the inner cylindrical body 6, and a drive switch 9 of the drill 4 and a drive switch 10 of the drill feed mechanism 3 are provided on the grip portions 8. . The plug of the electric cable 4a extending from the drill 4 is connected to a socket (not shown) provided on the grip portion 8. The column 2 is made portable, and a vibration isolator 7 provided at the bottom thereof is erected on a support surface 11 such as a floor, and the drill tip of the drill 4 is attached to a perforated surface 12 such as a ceiling surface.
It is set for.

FIG. 2A is an enlarged perspective view of the column 2 and FIG.
(B) is a cross-sectional view in which it is further partially enlarged.
In these figures, a plurality of through-holes 6a are provided at equal intervals along the axial direction in an inner cylindrical body 6 constituting a column 2, and one through-hole corresponding to the through-hole 6a is formed in an outer cylindrical body 5. 5a are provided. The through-hole 5a and an arbitrary through-hole 6a are made to coincide with each other, and the insertion pin 13 is externally connected to the through-hole 5a
Can be adjusted to a predetermined length. The insertion pin 13 has an enlarged head and a shaft, and is engaged with a holding frame 15 attached to the outer cylindrical body 5 with a return spring 14 attached to the shaft so as not to fall off. . When the insertion pin 13 is inserted with the through holes 5a and 6a aligned, the insertion pin 13 is moved by the action of the return spring 14 into the through holes 5a and 6a.
It is automatically inserted into and keeps its state.

FIG. 3 is an enlarged front view of a peripheral portion of the drill feed mechanism 3, and a part thereof is shown in a sectional view so that the inside can be seen. The drill feed mechanism 3 is connected to a connecting body 16 formed in a cylindrical shape, a coiled compression spring 17 housed in the connecting body 16, a driving unit 18 such as a small motor, and an output shaft of the driving unit 18. And a lifting nut member 20 screwed to the long bolt 19. A drill 4 is detachably connected to an upper end of the connecting body 16 through a mounting bracket 4b with a thumb screw, and a lower end is inserted into the inner cylindrical body 6 of the support column 2, and a lower end is further attached to the lower end. A tip end of the bolt 19, a thick flange body 21 slidably inserted therein, a lifting nut member 20, and the like are inserted. The lower end of the compression spring 17 is pressed by the flange body 21, and the upper end of the compression spring 17 is pressed by a ring-shaped stopper body 16 a fixed inside the middle part of the connecting body 16.

FIGS. 4 to 6 are cross-sectional views showing a further enlarged portion of the long bolt 19 in the drill feed mechanism 3 and the lifting nut member 20 screwed thereto. The lifting nut member 20 is a split nut composed of a plurality of divided pieces 20a. As shown in FIG. 5, each divided piece 20a has an internal screw 20b for screwing to the long bolt 19 on its inner peripheral surface. A rod-shaped connecting member 20 extending in the radial direction is provided on the outer peripheral portion.
c is provided. Each connecting member 20c is connected to the connecting body 16
And penetrate through the inner cylindrical body 6 of the column 2, and their distal ends are connected to the operation lever 22. Further, between the connecting body 16 and the outer peripheral surface of the divided piece 20a, a coil-shaped compression spring 23 is mounted on each connecting member 20c.

A fulcrum portion 22a is provided at an intermediate portion of each operation lever 22 to be in contact with the outer peripheral surface of the inner cylinder 6, and when each of the operation levers 22 is operated as a fulcrum as shown by a dotted line in FIG. When the operation lever 22 is released, the operation of the compression spring 23 returns the operation lever 22 to the solid line state, and the long bolt 19 and the division piece 20a are again screwed. To wear.
The connecting member 20c, the operating lever 22, and the compression spring 23 constitute a moving unit 24 that moves each of the divided pieces 20a in the radial direction. FIG. 6 is a cross-sectional view showing a state in which the divided piece 20a and the long bolt 19 are screwed. The length of the arc of the divided piece 20a is preferably a dimension slightly smaller than １ ／ of the outer circumference of the long bolt 19.

FIG. 7 is an enlarged side view of a peripheral portion of the drill feed mechanism 3. A pair of elongated slits 25 are formed facing each other along the axial direction of the inner cylindrical body 6 of the support column 2, and the connecting members 20 c extending from the respective divided pieces 20 a penetrate through the respective slits 25. As described later, when the long bolt 19 is rotated by the driving unit 18, the connecting member 20 c of the lifting / lowering nut member 20 is guided by the slit 25 and moves in the axial direction of the inner cylindrical body 6 to compress the compression spring 17. Then, the connecting body 16 is slid coaxially with respect to the column 2.

FIG. 8 is a front view showing another example of the punching device of the present invention. This example differs from the example of FIG. 1 only in that the drill feed mechanism 3 is of a dust-proof type, and the other parts are configured similarly. The same parts as those in the example of FIG. 1 are denoted by the same reference numerals. 3 before, after and around the drill feed mechanism 3
Two bellows-type covers, namely an upper bellows cover 26, a middle bellows cover 27 and a lower bellows cover 28. The upper end of the upper bellows cover 26 is fixed to the lower part of the mounting bracket 4 b of the drill 4, and the lower end is fixed to the outside of the upper end of the grip 8. The upper end of the middle bellows cover 27 is fixed to the inside of the upper end of the grip portion 8, and the lower end is fixed to the outer peripheral surface of the inner cylindrical body 6 located above the connecting member 20 c of the lifting nut member. Is fixed to the outer peripheral surface of the inner cylindrical body 6 located below the connecting member 20c,
The lower end is fixed inside the lower end of the grip 8.

FIG. 8 shows a state in which the drilling drill 4 made of a spiral cable and the driving wires 29 of the drill feed mechanism 3 are inserted into the support column 2. The drive wiring 29 of the drill 4 is an outlet (not shown) of the grip portion 8 to which the plug of the electric cable 4a is connected.
And the control unit 100 are connected, and the drive wiring 29 of the drill feed mechanism 3 is connected to the drive unit 18 provided on the inner cylinder 6 and the control unit 1.
Connect between 00. The control unit 100 is provided with a safety device such as a power receiving unit and a breaker.

FIGS. 9A and 9B are enlarged sectional views of the vibration isolator 7 provided at the bottom of the column 2. FIG. 9A shows the column 2 set perpendicular to the support surface 11, and FIG. The state when inclined and set with respect to the support surface 11 is shown. The vibration isolator 7 has a two-layer structure including a flexible vibration isolating layer 30 that is in contact with the support surface 11 of the column 2 and a hard vibration isolating layer 31 that is harder than the flexible vibration isolating layer 30. For example, a soft rubber having a hardness of about 20 to 50 can be used for the flexible vibration isolating layer 30, and a hardness of 6
Hard rubber of about 0 to 90 can be used. The transmission of the vibration generated by the perforation to the support surface 11 is suppressed by both the soft vibration-proof layer 30 and the hard vibration-proof layer 31,
The anti-slip action for 1 is achieved by the flexible vibration isolating layer 30. Also, when the support 2 is set to be inclined with respect to the support surface 11 as shown in FIG.
Is stably supported.

Next, a method of perforating an anchor hole on a perforated surface such as a ceiling surface made of concrely by the perforating apparatus will be described. First, as shown in FIG. 1, the drilling device 1 is erected at a predetermined position on the support surface 11 by gripping the grip portion 8 with a hand, and the column 2 is positioned so that the drill tip of the drill 4 is almost in contact with the drilling surface 12. Adjust the length (see FIG. 2). Prior to the start of drilling, if necessary, with the drill 4 pressed slightly downward against the compression spring 17 (see FIG. 3), the tip of the drill is made to coincide with the drilling position (marking position). By returning the position of the drill 4 to the original position, the positioning of the drill can be performed accurately. Next, while holding the grip portion 8, the drive switches 9, 1
When the operator operates 0 to activate the drill 4 and the drill feed mechanism 3, the drill 4 is fed by the drill feed mechanism 3 while rotating, and drilling proceeds. The punching operation can be performed stably by firmly gripping the grip portion 8 with both hands. That is, the impact can be reduced even if the drill hits the embedded reinforcing bar during drilling, and the drill 4 and the drill feed mechanism 3 can be stopped immediately.

Next, the operation of the drill feed mechanism 3 itself will be described. When the drill switch mechanism 3 is started by operating the drive switch 10, the drive unit 18 rotates the long bolt 19, whereby the lifting / lowering nut member 20 is connected to the inner cylindrical body of the support column 2. 6 slit 25 (FIG. 7)
) And move in the axial direction. Then, the flange body 21 slidably inserted into the long bolt 19 is pushed up by the lifting nut member 20, whereby the compression spring 17 is compressed. Since the connecting body 16 presses the drill 4 in the direction of pressing against the drilling surface 12 by the compression of the compression spring 17, the drill 4 is automatically sent out as the drilling progresses. Then, even when perforation unevenness occurs, the effect of the compression spring 17 is effectively absorbed. After the completion of the drilling operation, drill 4
And the drill feed mechanism 3 is stopped. Next, each operating lever 22 is operated as shown by a chain line in FIG.
The screw connection between the 0 and the long bolt 19 is released. Then, the mechanical connection between the drill 4 and the drill feed mechanism 3 is substantially released, so that the drill 4 can be easily pulled out from the drilled hole. The drill 4 may be stopped after the drill 4 is pulled out from the drilled hole.

[0023]

As described above, according to the drilling device of the first aspect, the drill feed mechanism is provided on the axis of the column, and the drill is arranged on the axis of the column.
For example, when piercing a concrete ceiling surface, the reaction force of the piercing drill is transmitted directly to a support surface such as a floor along the axis of the column. For this reason, no bending stress is generated in the column, so that its structural strength and dimensions can be designed to be small. In addition, since the drill feed mechanism and the drill do not protrude significantly in the lateral direction of the column, the entire drilling device can be made compact. The invention according to claim 2 is the drilling device, wherein the drill feed mechanism is coaxially slidable on the column, and a driving unit provided in the column for driving the column in the axial direction. And a drill is connected to the connection body, whereby the structure of the drill feed mechanism is simplified, and it can be easily provided on the axis of the column.

According to a third aspect of the present invention, in the above-described drilling device, the connecting body in the drill feed mechanism is driven by a driving unit via a compression spring.
As a result, the compression spring effectively absorbs the difference between the unevenness of the drilling speed and the constant feed speed by the drill feed mechanism, so that a reasonable and smooth drilling operation can be performed. In addition, since the compression spring absorbs the vibration from the drill, the vibration generated by the drilling can be prevented from being directly transmitted to the support, and the magnitude of the reaction force from the support to the support surface such as the floor is constant. The following can be suppressed. Prior to the start of drilling, the drill tip is aligned with the drilling position while the drill is pressed slightly downward against the compression spring, and then the drill is returned to its original position. In addition, the support can be set upright at a predetermined position.

According to a fourth aspect of the present invention, in the drilling device, the compression spring in the drill feed mechanism is housed in a cylindrically connected body, and the elevating nut member is mounted on a long bolt rotated by a driving unit. It is screwed and the lifting nut member compresses the compression spring by the rotation of the long bolt so that the coupling body slides coaxially with the support column, thereby making the structure of the drill feed mechanism simpler. And the whole apparatus can be made more compact. The invention according to claim 5 is the drilling device, wherein the lifting nut member in the drill feed mechanism is a split nut composed of a plurality of divided pieces, and moving means for moving each divided piece in the radial direction is provided. The screw of the lifting nut member to the long bolt can be released by the means, whereby the screwing of the lifting nut member is released after drilling and the compression spring is returned to the state before compression. By pushing down the drill, the drill can be more easily extracted from the drilled hole.

According to a sixth aspect of the present invention, in any one of the above-described drilling apparatuses, the supporting pillar is provided with a grip portion for gripping, and the grip portion is provided with a driving switch for a drill and a drill feed mechanism. The feature is that when such a grip portion is provided, the drilling drill and the drill feed mechanism can be started in a state where the grip portion is gripped by hand and the support is stably stood. In addition, a stable punching operation can be performed by firmly grasping the grip portion with both hands during the punching operation. Further, the grip portion can be easily moved by grasping with one hand. According to a seventh aspect of the present invention, in any one of the above-described drilling devices, the drill feed mechanism is of a dust-proof type. Can be prevented from penetrating into the vehicle.

According to the invention of claim 8, in any one of the above-mentioned perforating apparatuses, a vibration isolator is provided at the bottom of the column, and the vibration isolator includes a flexible vibration isolating layer in contact with the support surface of the column, and a harder layer than that. It is characterized in that it has a two-layer structure of a hard vibration isolating layer. By providing such a vibration isolating body, transmission of vibration generated by perforation to a support surface such as a floor is suppressed, and for example, a ceiling portion is formed. In the case of obliquely drilling the hole for anchoring avoiding the buried reinforcing bar, even if the support is installed obliquely, the support of the support can be stably supported by the support surface by the action of the flexible vibration isolating layer . According to a ninth aspect of the present invention, in any one of the above-described perforating apparatuses, the column is formed in a cylindrical shape, and a driving wire made of a spiral cable is inserted into the column. The wiring is accommodated in the column to improve the operability and appearance of the device, and the use of the spiral cable makes it difficult for the internal cable to be damaged even if the device is repeatedly expanded and contracted, so that the reliability of the device can be further improved.

[Brief description of the drawings]

FIG. 1 is a partially cutaway front view showing an example of a punching device of the present invention.

FIG. 2 is an enlarged perspective view and an enlarged sectional view of a column 2 in FIG.

FIG. 3 is an enlarged cutaway front view of a peripheral portion of a drill feed mechanism 3 in FIG. 1;

4 is a long bolt 19 in the drill feed mechanism 3 of FIG.
Sectional drawing which expands and shows the nut member for raising / lowering screwed to it further.

FIG. 5 is a perspective view of a divided piece 20a in FIG.

FIG. 6 is a sectional view showing a state in which the divided piece 20a and the long bolt 19 in FIG. 4 are screwed together.

FIG. 7 is an enlarged side view of a peripheral portion of the drill feed mechanism 3 in FIG. 1;

FIG. 8 is an explanatory front view showing another example of the punching device of the present invention.

FIG. 9 is an enlarged sectional view of a vibration isolator 7 provided at the bottom of the column 2 in the drilling device of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Drilling apparatus 2 Prop 3 Drill feed mechanism 4 Drilling drill 4a Electrical cable 4b Mounting bracket 5 Outer cylinder 5a Through hole 6 Inner cylinder 6a Through hole 7 Vibration isolator 8 Grip section 9 Drive switch 10 Drive switch 11 Support surface 12 Drill Surface 13 Insertion pin 14 Return spring 15 Holding frame 16 Connecting body 16a Stopper body 17 Compression spring 18 Drive unit 19 Long bolt 20 Elevating nut member 20a Split piece 20b Internal screw 20c Connecting member 21 Flange body 22 Operating lever 22a Support point section 23 Compression spring 24 Moving means 25 Slit 26 Upper bellows cover 27 Middle bellows cover 28 Lower bellows cover 29 Wiring 30 Flexible vibration-proof layer 31 Hard vibration-proof layer 100 Control unit 101 Power cable

Claims (9)

[Claims] The present invention comprises a telescopic column, a drill feed mechanism provided on an axis of the column, and a drill 4 arranged on the axis of the column. A perforation device characterized in that it can be moved coaxially with respect to the support column 2 by a feed mechanism 3. 2. The drill feed mechanism 3 has a connecting member 16 slidable coaxially with respect to the column 2, and a driving portion 18 provided in the column 2 to drive the connecting member 16 in the axial direction. The drilling device according to claim 1, wherein the drilling drill (4) is connected to a tip of the connecting body (16). 3. The drilling device according to claim 2, wherein the connecting body is driven in the axial direction by a drive unit via a compression spring. 4. A compression spring 17 is accommodated in a tubular connecting body 16, and an elevating nut member 20 is screwed to a long bolt 19 which is rotationally driven by a driving unit 18.
The drilling device according to claim 3, wherein the lifting / lowering nut member (20) compresses the compression spring (17) by rotating the long bolt (19) to slide the connecting body (16) coaxially with the support (2). 5. The lifting nut member 20 includes a plurality of divided pieces 2.
A moving nut 24 is provided to move each divided piece 20a in the radial direction, and the moving nut 24 can release the screwing of the lifting nut member to the long bolt 19. Item 5. A perforation device according to item 4. 6. A grip portion 8 for gripping is provided on the column 2, and a drive switch 9 for the drill 4 is provided on the grip portion 8.
The drilling device according to any one of claims 1 to 5, further comprising a drive switch (10) for driving the drill feed mechanism (3). 7. The drilling device according to claim 1, wherein the drill feed mechanism 3 is of a dustproof type. 8. A vibration isolator 7, which also serves as a non-slip, is provided at the bottom of the column 2, and the vibration isolator 7 includes a flexible vibration isolating layer 30 which is in contact with the support surface 11 of the column 2, and a harder anti-skid layer. Vibration layer 3
The drilling device according to any one of claims 1 to 7, wherein the punching device has a two-layer structure. 9. The drilling device according to claim 1, wherein a driving wire 29 made of a spiral cable is inserted into the cylindrical support 2.