JP5593374B2 - Drilling tools - Google Patents

Description

  The present invention relates to a drilling tool capable of easily and accurately drilling at a drilling target position on a side surface of an object to be drilled.

  Conventionally, as this type of device, for example, the device described in Patent Document 1 below is known. The drilling device described in this document suspends a pair of V-shaped blocks that hold and fix a round bar as a drilled body from both sides, and a vertical drill disposed above the upper surface of the round bar to which a drill blade is applied. Holding means for holding and drill moving means for lowering the drill blade toward the round bar are provided. In this drilling device, the user lowers the drill by manually pulling down the operation lever of the drill moving means, and drills by hitting a drill blade at the drilling target position on the upper surface of the round bar.

JP-A-5-293706

By the way, the conventional perforating apparatus grips a round bar from both sides by a pair of V-shaped blocks. Therefore, when drilling on a round bar having a different outer diameter, a plurality of pairs of V-shaped blocks having different sizes are previously set. Since it is necessary to prepare, there is a problem that the cost of spare parts is increased. In addition, each time the V-shaped block must be replaced with a V-block moving screw, there is a problem that the replacement work takes time and effort.
On the other hand, since the drill held in the vertical posture moves up and down, drilling can be performed only on the upper surface of the rod-shaped body to be drilled. That is, there is a problem that the drilling cannot be performed at the target drilling position on the side surface of the rod-shaped drilled body installed sideways. In this case, it is conceivable to perform the drilling after turning the rod-shaped body to be drilled and rearranging the drilling target position on the upper surface, but some objects cannot be rotated and installed. For example, when there is a drilling target position on the side surface of a pipe that is curved in the horizontal direction, it is extremely difficult to support the pipe by arranging the bending direction up and down, and it is also difficult to align the drill blade.
On the other hand, a use mode in which a drilling device for vertically moving a drill in a vertical posture is horizontally arranged and moved horizontally can be considered, but such a use mode can be applied only to a comparatively lightweight small drill.

  The present invention has been made in view of the above-described conventional problems, and provides a drilling tool that can surely perforate the side surface of a rod-like body to be drilled that is disposed substantially horizontally. Objective.

In order to achieve the above object, a drilling tool according to the present invention comprises a main body casing, a drill blade that can be moved forward and backward in the front portion of the main body casing, a drill blade that is provided in the main body casing, A rotary drive source for rotational driving, a drill blade moving shaft that is arranged coaxially with the drill blade at the rear part of the main body casing and protrudes rearward from the casing rear end of the main body casing, and for moving the drill blade A shaft rotating operation portion for rotating a drill blade moving shaft provided at a portion projecting rearward from the shaft main body casing, and the drill blade is inserted into the main body casing by the rotation of the shaft rotating operation portion. The drill configured to protrude and retract from the front end of the drill is a drilling tool to be mounted, and supports the surface opposite to the surface where the drilling target position of the rod-shaped drilled body is located Therefore, the drill body casing is suspended by placing the drilled body support member wound around the opposite surface and the drill blade in a substantially horizontal direction and facing the drilling target position of the drilled body. A suspension member for lowering, a shaft support member for rotatably supporting the rear end portion of the drill blade moving shaft, and two connections for connecting the both end portions of the shaft support member and the both end portions of the drilled body support member , respectively. And the drilled body support member, the shaft support member, and the two connecting members are made of steel, and the drilled body support member, the shaft support member, and the two connection members are connected to each other. And when the drill blade drills a target drilling position of the body to be drilled, the rear end portion of the drill blade moving shaft is freely rotatable by the auxiliary shaft support member. the thrust supported Ru configuration in mind the direction To have.

Further, in the above configuration, the circular handle rotatably supported on the front surface of the shaft support member connected to the connecting member, and the rear end portion of the drill blade moving shaft fixed to the front surface of the circular handle. a secondary shaft supporting member, those that and a locking protrusion which is detachably attached to the shaft rotation operating portion of the drill is fixed to the front surface of a circular handle.

  In each of the above-described configurations, the connecting member supports the through hole formed in the vicinity of the drilled body support member in the vertical direction and the drilled body applied to the inner surface of the drilled body support member. In order to do so, a holding pin inserted through the through hole is provided.

  According to the drill hole drilling tool according to the present invention, since the hanging member suspends the horizontal drill, even a large drill having a relatively heavy weight can be applied. The drilled body support member supports the side surface of the drilled body, and the shaft support member supports the rear end portion of the drill blade moving shaft of the drill. Therefore, when the user rotates the shaft for moving the drill blade, the drill blade advances toward the side surface of the drilled body, so that the drill can be reliably drilled with a simple operation. Incidentally, even if the drilled body is curved in the horizontal direction, a hole toward the center of curvature of the drilled body can be drilled on the side surface of the drilled body. Moreover, this drilling tool can be realized with a simple and inexpensive configuration.

Further, a circular handle to be rotatably supported by the shaft support member, and the sub shaft support member for supporting the rear end of the drill bit movement axis, a locking projection which is detachably attached to the shaft rotation operating part of the drill, With this, it is possible to easily rotate the shaft rotating operation section and the drill blade moving shaft using a circular handle that is easy to operate. Thereby, it is possible to drill by making the drill blade advance to the drilling target position of the drilled body very easily.

  Since the holding pin inserted through the position adjusting hole of the connecting member supports the drilled body applied to the inner surface of the drilled body support member forward, the holding pin and the drilled body support member A to-be-punched body can be reliably held between. Thereby, it can prevent that a to-be-punched object leaves | separates from the inner surface of a to-be-drilled body support member with a drill blade at the time of extraction of the drill blade after drilling.

It is a figure which shows the drill drilling tool which concerns on one Embodiment of this invention, Comprising: (a) is a side view, (b) is a top view. It is a rear view of the drilling tool. It is a plane sectional view of the drill with which the said drill drilling tool is applied. It is a side view which shows the state at the time of mounting | wearing the said drill hole drilling tool with a drill and perforating a pipe. FIG. 5 is a plan view corresponding to FIG. 4 and partially cut away. It is the partial external view which looked at the state which mounted | worn the said drill hole drilling tool to the drill from diagonally forward. It is the external view which looked at the state just before drilling to a pipe with the drill with which the said drill hole drilling tool was mounted | worn from diagonally back.

Embodiments of the present invention will be described with reference to the drawings. The embodiment described below is merely an example embodying the present invention, and does not limit the technical scope of the present invention. FIG. 1 is a view showing a drilling tool according to an embodiment of the present invention, wherein (a) is a side view, (b) is a plan view, and FIG. 2 is a rear view of the drilling tool.
In each drawing, a drilling tool 1 according to this embodiment includes a drilled body support member 2 that is hung around a pipe (an example of a rod-shaped drilled body) described later, and a drill D that will be described in detail later. A suspension member 24 for suspending the main body casing 30, a shaft support member 4 having a shaft support portion 28 that rotatably supports a rear end portion 50 </ b> A of a drill blade moving shaft 50 as indicated by an arrow R <b> 1, and a vertical direction Two connecting members 3 and 3 for connecting the upper and lower tip portions 4C and 4C of the disposed shaft support member 4 and the upper and lower portions of the drilled body support member 2 and the shaft rotation of the drill D provided on the shaft support member 4 And a rotary operation unit 27 that is detachably hooked to the operation unit 51.

  The said to-be-punctured body support member 2 is comprised, for example with the steel plate etc., and is formed in the shape of the roll-over U shape seeing from the side surface. The inner surface 2A on the back side of the perforated body support member 2 is for supporting the surface P2 on the opposite side of the surface P1 where the drilling target position T is located in the pipe P. A cylindrical portion 6 extending in the left-right direction is formed at the upper and lower rear ends of the perforated body support member 2. On the other hand, on the upper and lower sides of the perforated body support member 2, connecting members 3 and 3 made of, for example, long steel plates are provided. A cylindrical portion 6 is also formed at the front end portions of the connecting members 3 and 3. The cylindrical portion 6 of each connecting member 3 and the cylindrical portion 6 of the drilled body support member 2 are arranged in series in the left-right direction, and a pin 7 is inserted into the series of cylindrical portions 6, 6. Thereby, the upper and lower connecting members 3 are swingable up and down as shown by the arrows R2 with respect to the perforated body support member 2. That is, the hinge part 5 is comprised from the cylinder part 6 of each connection member 3, the cylinder part 6 of the to-be-punctured body support member 2, and the pin 7. FIG. A rear end hook 11 on which a hanging rope 26 (see FIG. 4) is hung is projected from the rear end portion of the upper connecting member 3.

In each connecting member 3, rod holes 9 are formed vertically penetrating to the left and right of the rear position in the vicinity of the cylindrical portion 6. The holding rod 22 (see FIG. 4) is inserted into the rod holes 9 and 9 facing vertically. The holding pin 23 prevents the pipe P applied to the inner surface 2A of the drilled body support member 2 from escaping backward. In the vicinity of the rod hole 9, a plurality of holding position adjusting holes 8 are formed vertically penetrating at appropriate intervals. In the upper and lower connecting members 3, 3, the holding rod 22 is inserted into the set of rod holes 9 , 9 facing vertically. The holding rod 22 fixes the angle of the upper and lower connecting members 3, 3 that swing up and down via the hinge portion 5, and a male screw portion is formed on the rod outer peripheral surface. The female screw portion of the nut 14 is screwed into the male screw portion of the holding rod 22, and each connecting member 3 is positioned and held by two nuts 14 and 14 sandwiched from above and below. As the set of the holding position adjusting holes 8 and 8 facing vertically, an appropriate set corresponding to the pipe diameter of the pipe P is selected.

  The shaft support member 4 is made of, for example, L-shaped steel, and is integrally formed from a member main body 4A arranged in the vertical direction and a reinforcing portion 4B protruding rearward at a right angle from the member main body 4A. Has been. On the other hand, in the vicinity of the rear end of each connecting member 3, a plurality of position adjusting holes 10, 10, 10 are formed penetrating up and down at appropriate intervals in the front-rear direction. In the upper and lower connecting members 3, 3, the upper and lower tip portions 4 </ b> C of the member main body 4 </ b> A are inserted into sets of the position adjusting holes 10 that face vertically. The shaft support member 4 is retained by a nut 14 screwed onto a bolt 13 that is passed through a bolt hole (not shown) in the vicinity of the upper and lower tip portions 4C of the member main body 4A.

A shaft plate 12 is fixed with bolts 13 on the front surface of the member main body 4 </ b> A, which is a substantially central portion of the shaft support member 4. A pivot shaft 15 protrudes forward from the front surface of the shaft plate 12. The pivot shaft 15 is mounted in a pivot hole 17 of the pivot member 16, and pivotally supports the pivot member 16 as indicated by an arrow R1. A central portion of a circular ring-shaped handle 18 is fixed to the front surface of the pivot member 16 in a front view. Further, on the front surface of the circular handle 18 central, sub-shaft support member 19 having a bearing hole 20 in which the front is open is fixed. On the front surface of the sub-shaft support member 19, a pair of locking protrusions 21, 21 in the hook-shaped is projected. The pair of locking protrusions 21 and 21 are detachably hooked to the shaft rotation operating portion 51 of the drill D. That is, a circular handle 18, a sub-shaft support member 19 having a bearing hole 20, a pair of locking projections 21, 21 Prefecture, rotation operating part 27 of the is formed.
The suspension member 24 is made of, for example, a rope or a steel wire, and is suspended from a suspension frame 25 disposed at an upper position of the drilling tool 1 to suspend the drill D. ing.

  As shown in FIG. 3, the drill D in which the drilling tool 1 is used includes a main body casing 30 having a bearing hole 31 penetrating in the front-rear direction, and a drill blade rotation disposed at the front portion in the bearing hole 31. A shaft 37, an air motor (an example of a rotational drive source) 38 that is disposed in the main body casing 30 to rotationally drive the drill blade rotation shaft 37, and a drill blade movement shaft 50 that is disposed in the rear part in the bearing hole 31. A blade feeding sleeve 49 interposed between the bearing hole 31 and the drill blade moving shaft 50; a sleeve moving mechanism 59 provided between the drill blade moving shaft 50 and the blade feeding sleeve 49; A shaft rotation operating portion 51 provided on a drill blade moving shaft 50 protruding rearward from the casing rear end portion 30B of the casing 30 is configured. A drill blade mounting hole 47 for mounting the drill blade 48 is formed in the front portion of the drill blade rotation shaft 37. A chuck portion 58 for fixing the drill blade 48 mounted in the drill blade mounting hole 47 to the drill blade rotation shaft 37 is provided at the front end portion of the drill blade rotation shaft 37.

  The main casing 30 includes a cylindrical main case 32 that is open at the front and rear, a rear lid portion 33 that seals the rear opening of the main case 32, an intermediate case 34 that is attached to the front opening of the main case 32, The front case 35 is attached to the front opening of the middle case 34, and the cap portion 36 is attached to the front opening of the front case 35. A series of bearing holes 31 are formed from the main case 32 to the cap portion 36 constituting the main body casing 30. That is, the bearing hole 31 is formed to penetrate from the casing front end 30 </ b> A of the main body casing 30 to the casing rear end 30 </ b> B.

  The drill blade rotating shaft 37 is mounted at the front portion in the bearing hole 31 and is rotatably supported by the ball bearing 57 and the inner peripheral wall of the front case 35 around the hole center C of the bearing hole 31. A fourth gear 45 is fixed to the outer peripheral surface of the rear portion of the drill blade rotation shaft 37. Further, the drill blade rotation shaft 37 is configured to be movable back and forth along the hole center C of the bearing hole 31. A blade feeding sleeve 49 is mounted on the rear portion in the bearing hole 31 so as to be movable along the hole center C of the bearing hole 31. A female screw portion 49 </ b> A is formed on the inner peripheral surface of the blade feeding sleeve 49. A drill blade moving shaft 50 is mounted in the blade feeding sleeve 49 so as to be rotatable around the hole center C of the bearing hole 31. However, since the drill blade moving shaft 50 is thrust supported with respect to the main body casing 30, it does not move in the direction of the hole core C. On the outer peripheral surface of the drill blade moving shaft 50, a male screw portion 50B that is screwed with the female screw portion 49A of the blade feeding sleeve 49 is formed. That is, the sleeve moving mechanism 59 is constituted by the male screw portion 50B of the drill blade moving shaft 50 and the female screw portion 49A of the blade feeding sleeve 49. This sleeve moving mechanism 59 moves the blade feeding sleeve 49 along the hole center C of the bearing hole 31 by the rotation of the drill blade moving shaft 50.

  A handle portion 53 protrudes from one side surface of the main case 32, and an air supply pipe 52 that also serves as the handle portion protrudes from the other side surface. The air supply pipe 52 includes a connection nozzle 54 to which a hose from an air compressor (not shown) is connected, an air supply valve 55, an operation lever (not shown), and the like. The air supply pipe 52 is connected to the air motor 38. The air motor 38 includes a cylinder 39 formed in the main case 32, a driving blade 40 that is rotatably disposed in the cylinder 39, and a rotary shaft 41 that is fixedly disposed at the rotation center of the blade 40. It is configured. The blade 40 is rotatably supported by front and rear ball bearings 56 and 56. A first gear 42 is provided at the front end of the rotating shaft 41. The first gear 42 meshes with a second gear 43 that is rotatably supported by front and rear ball bearings 56 and 56. A front portion of the second gear 43 is a third gear 44. The third gear 44 meshes with the fourth gear 45 described above.

The operation of the drilling tool 1 configured as described above will be described below. In this case, the nut 14 is loosened by the user, the holding rod 22 is removed from the rod holes 9 of the upper and lower connecting members 3, 3, and the shaft support member 4 is also adjusted in position of the upper and lower connecting members 3, 3. A description will be given from a state in which the connecting members 3 and 3 are detached from the service hole 10 and can swing up and down via the hinge portions 5 and 5 with respect to the drilled body support member 2. As shown in FIG. 5 and FIG. 7, the pipe P to be perforated is curved in the horizontal direction, and is placed in a stable state on the floor of the work place or on the work table.
First, the user opens one of the upper and lower connecting members 3 and hangs the drilled body support member 2 around the surface P2 of the pipe P opposite to the plane P1 where the drilling target position T is located. The inner surface 2A of the member 2 is applied to the surface P2 of the pipe P. Then, the rear end hook 11 of the upper connecting member 3 is hung on a suspension rope 26 suspended from an upper frame (not shown). At this time, by adjusting the length of the hanging rope 26 as appropriate, drilled hole as the sub-shaft supporting member 19 and the line connecting the tube mind pipe P drill drilling tool 1 is substantially horizontal The posture of the tool 1 can be determined.

Subsequently, the main body casing 30 is suspended by inserting the air supply pipe 52 and the handle portion 53 of the drill D into the lower ring portion of the suspension member 24 suspended from the suspension frame 25. Then, the rear end portion 50 </ b> A of the drill blade moving shaft 50 of the drill D is inserted into the bearing hole 20 of the auxiliary shaft support member 19 of the shaft support portion 28. At this time, the locking projections 21 and 21 are locked to the two shaft rotation operation portions 51 and 51. Next, by adjusting the suspension lengths of the suspension member 24 and the suspension rope 26 and the positions of the suspension member 24 and the suspension frame 25, the drill blade 48 of the drill D is directed in a substantially horizontal direction. In addition, the drill D is arranged so as to face the drilling target position T of the pipe P. In this state, a set of upper and lower position adjusting holes 10 and 10 to which the tip portions 4C and 4C of the shaft support member 4 are mounted is selected. In this case, the position of the set of the position adjusting holes 10 and 10 is selected so that the tip of the drill blade 48 is as close as possible to the drilling target position T. In this example, for example, the upper and lower set of the position adjusting holes 10 and 10 in the middle in the front-rear direction is selected (see FIG. 1).

After the upper and lower tip portions 4C and 4C of the shaft support member 4 are inserted into the selected upper and lower set position adjusting holes 10 and 10, the bolts 13 are passed through the bolt holes of the tip portions 4C and 4C. It is prevented from coming off by screwing (see FIG. 4). Thereafter, the holding rods 22 and 22 are passed through the left and right and upper and lower rod holes 9, 9, 9 and 9, and then tightened and fixed by the nut 14. With the holding rods 22 and 22 tightened in this way, the pipe P is held in close contact with the upper and lower surfaces 2 </ b> A of the drilled body support member 2. Furthermore, the holding pin 23 is inserted into the set of the holding position adjusting holes 8 , 8 either before or after the upper and lower connecting members 3, 3. With the holding pins 23 inserted in this way, escape of the pipe P in the direction of the drill P is avoided.
Therefore, when the user operates the drive lever of the drill D, the compressed air from the air compressor is guided to the air supply pipe 52 and further flows into the cylinder 39 through the air supply valve 55. Thereby, the rotary blade 40 is rotationally driven. The rotation of the rotary blade 40 is transmitted from the first gear 42 integrated with the rotary shaft 41 to the second gear 43 and further transmitted from the third gear 44 to the fourth gear 45 so that the drill blade rotary shaft 37 and the drill blade 48 are integrated. Rotate to The drill blade 48 rotates at a position immediately before contacting the pipe P.

Subsequently, as shown in FIG. 7, when the user rotates the circular handle 18 of the rotation operation unit 27 as indicated by an arrow R <b> 3, the shaft rotation operation unit 51 of the drill D is moved via the locking projection 21. The drill blade moving shaft 50 is rotated. As a result, the blade feeding sleeve 49 screwed with the drill blade moving shaft 50 advances in the direction (arrow F) toward the pipe P to push the drill blade rotating shaft 37, and the drill blade 48 is moved to the pipe P. Advance toward the drilling target position T. Among them, the tip of the drill blade 48 comes into contact with the drilling target position T. While the reaction force in the opposite direction of the time arrow F is applied to the drill bit 48, and the rear end portion 50A of the drill bit moving shaft 50 is thrust supported by the bearing hole 20 of the sub-shaft support member 19 of the drill drilling tool 1 Therefore, the drill blade 48 is not returned in the direction opposite to the arrow F. Then, when the drill blade 48 further advances, the pipe P is drilled. After the drilling at the drilling target position T is completed, the user turns the circular handle 18 of the rotary operation unit 27 in the direction of the arrow R4, so that the drill blade 48 moves backward in the direction opposite to the arrow F and the pipe P It is extracted from the perforated part. At this time, a force in the direction opposite to the arrow F is applied to the pipe P due to the frictional force between the perforated portion of the pipe P and the outer peripheral surface of the drill blade 48, but the pipe P is opposite to the arrow F due to the presence of the holding pin 23. It is held in that position without moving in the direction.

As described above, according to the drilling tool 1 of this embodiment, the hanging member 24 suspends the horizontal drill D arranged in the drilling tool 1, and the drilled object support member 2 is The surface P2 of the pipe P is supported rearward, and the shaft support portion 28 of the shaft support member 4 supports the rear end portion 50A of the drill blade moving shaft 50 of the drill D forward. That is, the pipe P is to be supported by the piercing member supporting member 2 and the holding pin 23 of the drill drilling tool 1, the rear end of the drill D is a fixed point supported by the sub-shaft supporting member 19 of the drill drilling tool 1 Therefore, the centering operation of the tip of the drill blade 48 can be performed easily and accurately by adjusting the length and position of the suspension member 24 and the suspension frame 25 as appropriate. Thus, the pipe P and the drill D are supported from the front and rear in the drilling tool 1. Therefore, by rotating the circular handle 18 of the rotation operation unit 27, the drill blade 48 can be advanced to the surface P1 of the pipe P to perform drilling. Incidentally, even in the case of the pipe P curved in the horizontal direction, the hole toward the center of curvature of the pipe P can be surely drilled in the side surface (surface P1) of the pipe P by a simple operation.

Further, a drill blade moving shaft 50 for advancing the drill blade 48 is pivotally supported by the shaft support portion 28 of the drilling tool 1, and the locking projection 21 of the rotation operation portion 27 is detachably attached to the shaft rotation operation portion. 51, and the locking protrusion 21 is connected to the circular handle 18, so that the shaft rotating operation portion 51 and the drill blade moving shaft 50 are rotated very easily using the circular handle 18 that is easy to operate. Can be perforated.
And since the holding pin 23 inserted through the position adjusting holes 8 and 8 of the connecting members 3 and 3 supports the pipe P applied to the inner surface 2A of the drilled body support member 2 forward, The pipe P can be reliably held between the pin 23 and the inner surface 2A of the drilled body support member 2. Thereby, at the time of extracting the drill blade 48 after drilling, it is possible to prevent the pipe P from being separated from the inner surface 2 </ b> A of the drilled body support member 2 along with the drill blade 48. Thus, the drilling tool 1 of the present embodiment can be suitably used for drilling curved pipes used for spherical tanks for LPG and LNG in oil refineries.

In the above embodiment, the upper and lower ends of the perforated body support member 2 are provided with hinge portions 5 and 5 so that the upper and lower connecting members 3 and 3 can swing up and down with respect to the perforated body support member 2. Although configured, the drilling tool of the present invention is not limited thereto. For example, it is possible to omit either the upper or lower hinge 5 and integrally form the omitted connecting member 3 and the drilled body support member 2.
In addition, the rod-shaped perforated body to which the present invention is applied is not limited to the above-described pipe (steel pipe), and may be, for example, a rod made of metal or synthetic resin.

DESCRIPTION OF SYMBOLS 1 Drilling tool 2 Drilled body support member 3 Connection member 4 Shaft support member 5 Hinge
8 Holding position adjustment hole (through hole)
15 pivot 16 pivot member 17 pivot support hole 18 circular handle 19 sub shaft support member 20 bearing hole 21 hanging locking projection 23 holding pin 24 member 25 for hanging the frame 27 rotation operation portion 28 the shaft support 29 rotating operation unit 30 Main Body Casing 30A Casing Front End 30B Casing Rear End 37 Drill Blade Rotary Shaft 38 Air Motor (Rotation Drive Source)
48 Drill Blade 49 Blade Feeding Sleeve 49A Female Threaded Port 50 Drill Blade Moving Shaft 50A Rear End 50B Male Threaded Portion 51 Shaft Rotating Operation Unit 59 Sleeve Moving Mechanism C Core D Drill P Pipe (Bar-shaped Drilled Body)
P1, P2 surface T Drilling target position

Claims (3)

A main body casing, a drill blade that can be moved forward and backward at the front of the main body casing, a rotational drive source that is disposed in the main body casing and rotationally drives the drill blade, and a drill blade coaxial with the drill blade at the rear of the main body casing The drill blade moving shaft that is arranged in a freely rotatable manner and protrudes rearward from the rear end of the casing of the main body casing, and the drill blade movement that is provided in a portion protruding rearward from the main body casing of the shaft for drill blade movement A drill having a shaft rotating operation portion for rotating the shaft, and configured to cause the drill blade to protrude and retract from the front end portion of the main body casing by the rotation of the shaft rotating operation portion. A drilling tool,
A to-be-pierced body support member that is hung around the opposite surface to support the surface opposite to the surface on which the drilling target position of the rod-shaped object is to be drilled;
A suspension member that suspends the drill's main body casing in such a manner that the drill blade is arranged in a substantially horizontal direction and is directed to the drilling target position of the drilled body,
A shaft support member that rotatably supports the rear end portion of the drill blade moving shaft;
Two connecting members for connecting the both ends of the shaft support member and the both ends of the perforated body support member , respectively ,
The perforated body support member, the shaft support member and the two connecting members are made of steel, and the perforated body support member, the shaft support member and the two connecting members are connected to form a frame shape. with, when the drill bit is drilling a drilling target position of the object to be perforated body, the rear end portion of the drill bit movement shaft is thrust supported rotatably and axially in the secondary shaft support Rukoto Drilling tool characterized by. A circular handle to be rotatably supported on the front of the shaft support member connected with the connecting member, and the secondary shaft support member for supporting the rear end of the drill bit movement axis fixed to the front face of the circular wheel The drilling tool according to claim 1, further comprising: a locking projection fixedly attached to a front surface of the circular handle and detachably attached to a shaft rotation operation portion of the drill. The connecting member is inserted through the through hole formed in the vicinity of the drilled body support member in the vertical direction and the drilled body applied to the inner surface of the drilled body support member forwardly. The drilling tool according to claim 1 or 2, further comprising a holding pin to be operated.

Images