JP2005144568A - Drilling tool - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a drilling tool in which a center shaft part of a center drill or the like can be made into a irrotational state with respect to a body and a freely extendable/contractible state with a simple structure without working the center shaft part of the center drill or the like, and consequently, the whole tool can be inexpensively manufactured. <P>SOLUTION: The drilling tool is provided with the body 10 having a shaft body 20, a cutting blade 30, which is extended from the body 10 and rotates integrally together with the body 10 so as to drill a through-hole to a body to be drilled, the center drill 40, which is extended from the body 10 and becomes the rotational center of the cutting blade 30, and holding members 50, 60, 70, and 80 in which one end side is mounted in the irrotational state with respect to the body 10 and which hold the center drill 40 in the rotation stopped state by the other end side and make the center drill 40 to rotate integrally together with the body 10. The holding members urges the center drill to a first position by a leaf spring 50 and allow the center drill 40 to elastically retract to a second position during drilling. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a punching tool for drilling a circular hole in a plate material such as a plywood or a gypsum board used for a wall of a building.

Conventionally, as a punching tool for penetrating and forming a circular hole in an object to be punched such as a plate material, for example, there are techniques described in Patent Document 1, Patent Document 2, or Patent Document 3.
Japanese Patent Laid-Open No. 10-23063 Japanese Utility Model Publication No. 63-97411 Japanese Utility Model Publication No. 1-74009

  Each of the techniques described in Patent Documents 1 to 3 has a center shaft, a center drill, or a center pin at the rotation center position of a drilling blade for forming a circular hole. The center shaft, the center drill, or the center pin provides a rotation center of the drilling blade by penetrating the tip of the drilled body into the drilled body when the drilled body is drilled by the drilling blade. In this document (Claims, Description and Abstract), when drilling a drilled body with a drilling blade, such as a center shaft, center drill, center pin, etc., the tip enters the drilled body, A member that provides the center of rotation of the drilling blade is referred to as a center shaft portion for convenience. In the techniques described in Patent Document 1 and Patent Document 2, the center shaft or the center drill advances (projects) from the tip of the drilling blade, and the retracted position retracts (immerses) from the tip of the drilling blade. It can be stretched between. On the other hand, in the technique described in Patent Document 3, unlike the techniques described in Patent Document 1 and Patent Document 2, the center drill is not telescopic with respect to the drilling blade and is always fixed at a position protruding from the drilling blade. .

  According to the drilling tool according to Patent Document 1 or Patent Document 2, when the drilled body such as a wall plate material is drilled by the drilling blade, the center shaft or the center drill moves backward with the advancement of the drilling blade. The center shaft or center drill does not penetrate the drilled body. For this reason, for example, since the opening of the wiring box installed on the back side (the back side of the wall) of the building faces the front side of the wall, the center drill uses the wall material when drilling a through hole in the wall material. It is possible to prevent the wiring box behind the wall and the contents in the wiring box from being damaged. On the other hand, in the technique described in Patent Document 3, a center pin can be replaced and attached instead of the center drill, and the type of the drilled body can be handled.

  Here, in the drilling tool of the type provided with the center drill as described in Patent Document 2, the center drill is prevented from rotating with respect to the main body so as to rotate integrally with the main body of the drilling tool that fixedly supports the drilling blade. It must be mounted in a heated state and urged so as to be telescopic. However, in the conventional drilling tool, it is indispensable to process the center drill itself in order to make the center drill non-rotating and extendable with respect to the main body. For example, in the technique described in Patent Document 2, a non-circular section having a cross section corresponding to a stroke necessary for expansion and contraction of the center drill is cut into the base end portion of the center drill.

  For this reason, the conventional punch has the following problems. First, since the processing of the center drill requires accuracy, the center drill itself greatly increases in cost, and the drilling tool itself cannot be provided at a low cost. Moreover, processing the center drill itself may weaken the strength of the center drill or cause damage. In addition, making the center drill non-rotatable and telescopic by processing the center drill causes a runout of the center drill. That is, if the center drill is held in a non-rotatable and telescopic manner by the center drill structure itself, there is a possibility that rattling occurs on the proximal end side of the center drill in the held state. Furthermore, in order to hold the center drill in a non-rotating state and extendably and contractably, a holding portion is provided at a position on the main body side corresponding to the base end side of the center drill. However, in order to secure a stroke necessary for the expansion and contraction of the center drill, the holding part becomes larger correspondingly, and the drilling tool itself becomes large and difficult to handle. Furthermore, for example, when a non-circular cross section is formed on the base end side of a center shaft portion such as a center drill as in Patent Document 2, the base end side of the center shaft portion is inserted into a hole in the center of the main body. It will guide the expansion and contraction of the shaft. At this time, both the means (part) for preventing the center shaft from rotating relative to the main body and the means (part) for expanding and contracting both are holes in the center of the main body into which the base end side of the center shaft is inserted. Part. Therefore, when the center shaft portion is expanded and contracted in the axial direction while rotating integrally with the main body, the center shaft portion has a flat portion of the cross-sectional non-circular portion on the base end side and both corner portions of the flat portion are holes of the main body. Will be pressed against the corresponding flat part or corner of the shaft, and will be prevented from rotating. In the expansion and contraction direction (stroke direction) of the center shaft part, a large resistance will be generated between the center shaft part and the hole part of the main body. There is a possibility that the expansion / contraction operation (stroke operation) of the shaft portion is not performed smoothly and troubles occur.

  Therefore, the present invention can make the center shaft portion such as the center drill non-rotating and extendable with respect to the main body with a simple structure without processing the center shaft portion such as the center drill, and as a result, It is an object of the present invention to provide a punching tool that can be manufactured as a whole at low cost.

  A punching tool according to claim 1 is provided with a main body having a connecting portion that can be connected to a rotating shaft of a driving portion of a rotating tool, and the main body extending from the main body so as to drill a through hole in a drilled body. A drilling blade that rotates integrally, a center shaft portion that serves as a rotation center of the drilling blade, and one end side that is attached to the main body in a non-rotating state, and the other end side prevents the center shaft portion from rotating. A holding member that holds the center shaft portion together with the main body so that the tip end of the center shaft portion is always more than the tip end of the drilling blade. It has elasticity to urge the center shaft portion in the direction from the proximal end side to the distal end side to the protruding first position, and in the direction from the distal end side to the proximal end side of the center shaft portion. Depending on the external force, the tip of the center shaft To a second position to retracted from the tip of the cutting head, the center shaft portion is allowed to elastically retract in the axial direction.

  According to a second aspect of the present invention, in the configuration of the first aspect, the piercing tool includes a plate-like member extending between the one end side and the other end side, and the one end side of the plate-like member. Is attached to the main body in a non-rotating state, and the center shaft portion is held in a non-rotating state by the other end side of the plate-like member, and the plate-like member has the center shaft portion and the first position. The holding member can be bent or bent between one end side and the other end side so as to be stretchable between the second position and the second position.

  According to a third aspect of the present invention, in the configuration of the second aspect, the perforating tool itself has elasticity that expands so that the plate-like member always has a maximum length between one end side and the other end side of the holding member. In the extended state, the center shaft portion is biased to the first position, and the center shaft portion contracts from the first position to the second position in response to the extension. It bends or curves elastically from the state.

  According to a fourth aspect of the present invention, in the configuration of the second or third aspect, the punch has a substantially plate-like base portion in which the punching blade is disposed on the outer periphery, and the connecting portion has a thickness of the base portion. The plate-shaped member has a shaft body integrally fixed to one side in the direction, and the one end side is fixed to the shaft body, penetrates the base portion in the thickness direction, and the center is formed by the other end side. Secure the shaft.

  According to a fifth aspect of the present invention, in the configuration according to any one of the first to fourth aspects, the projecting length of the center shaft portion held by the holding portion from the holding portion is such that the center shaft portion is to be drilled. The thickness is set to be less than the thickness of the perforated body so as not to penetrate.

  According to a sixth aspect of the present invention, in the configuration of the fifth aspect, the protruding length of the center shaft portion held by the holding portion from the holding portion can be changed according to the thickness of the drilled body. .

  According to a seventh aspect of the present invention, in the structure according to any one of the first to sixth aspects, the holding member further holds the center shaft portion in a state where the tip end portion of the center shaft portion protrudes by a predetermined length. A contact portion, and when the center shaft portion is drilled into the body to be drilled for the predetermined length, the tip of the contact portion contacts the surface of the body to be drilled, and more than the center shaft portion. The center shaft portion is retracted toward the second position against the elasticity of the holding member.

  According to an eighth aspect of the present invention, in the configuration of the fourth aspect, the drilling tool further includes an adjustment screw that is screwed into the base portion of the main body, passes through the base portion, and extends toward the other end side of the holding member; A regulating piece provided on the other end side of the member and disposed opposite to the tip of the adjusting screw, and when the center shaft portion is in the second position, the tip of the adjusting screw is placed on the regulating piece. The center shaft portion is prevented from further retracting from the second position by abutting.

  According to a ninth aspect of the present invention, in the configuration of the fourth aspect, when the center shaft portion is in the second position, the bent or curved portion of the plate-shaped member contacts the outer peripheral portion of the base portion of the main body. In contact therewith, the plate-like member is prevented from further bending or bending, and the center shaft portion is prevented from further retracting from the second position.

According to a tenth aspect of the present invention, there is provided a punching tool according to a tenth aspect, comprising: a main body having a connecting portion connectable to a rotating shaft of a driving portion of a rotating tool; A drilling blade that rotates integrally, a center shaft portion that serves as a rotation center of the drilling blade, and one end side that is attached to the main body in a non-rotating state, and the other end side prevents the center shaft portion from rotating. A holding member that is held in a state so that the center shaft portion rotates together with the main body, and the tip of the center shaft portion is always provided between the holding member and the main body. The center shaft portion is urged in the direction from the proximal end side to the distal end side to the first position protruding from the distal end of the drilling blade, and is directed from the distal end side to the proximal end side of the center shaft portion. Depending on the external force in the direction, To a second position where the end is retracted from the tip of the cutting head, the center shaft portion and an elastic member to allow the resiliently retracted in the axial direction.
The elastic member may be provided between the holding member and the main body inside the main body, or provided between the holding member and the main body outside the main body. Also good.

  A punching tool according to an eleventh aspect includes a main body having a connecting portion that can be connected to a rotating shaft of a driving portion of a rotating tool, and the main body extending from the main body to punch a through-hole in a drilled body. The piercing blade that rotates integrally, the center shaft portion that is the center of rotation of the piercing blade, and one end side attached to the piercing blade in a non-rotating state, and the other end side that rotates around the center shaft portion. The center shaft portion is held in a stopped state so that the center shaft portion rotates together with the main body, and the center shaft portion held by the other end side moves along the extending direction of the drilling blade. The one end side is provided between the holding member attached to the drilling blade and the holding member and the main body so as to be free, and the tip of the center shaft portion always protrudes from the tip of the drilling blade. The center shaft portion is moved to the first position. Urging in the direction from the proximal end side to the distal end side, and in response to an external force in the direction from the distal end side to the proximal end side of the center shaft portion, the distal end of the center shaft portion is And an elastic member that allows the center shaft portion to elastically retreat in the axial direction from the tip to a second position where the center shaft is retracted.

  According to a twelfth aspect of the present invention, in the configuration of any one of the first to eleventh aspects, the main body has a guide hole extending in the axial direction of the connecting portion, and the tip end side of the center shaft portion is the tip side. While being held in a non-rotating state by the other end side of the holding member so as to rotate integrally with the main body, its base end side is inserted into the guide hole of the connecting portion so as to be slidable in the axial direction. And is supported in a state in which movement in the radial direction is restricted by the guide hole of the connecting portion, and the expansion and contraction operation between the first position and the second position of the center shaft portion is guided by the guide hole of the connecting portion. Is done.

  According to a thirteenth aspect of the present invention, in the configuration of the twelfth aspect, the guide hole is provided through the connecting portion in the axial direction.

  According to a fourteenth aspect of the present invention, in the configuration according to any one of the first to thirteenth aspects, the drilling blade has a saw blade shape that is continuous in the circumferential direction of the main body.

  According to the punching device of the first aspect, the center shaft portion can be prevented from rotating with respect to the main body and can be expanded and contracted with a simple structure without processing the center shaft portion. Can be produced. In other words, by eliminating the processing of the center shaft portion, there is no core blurring of the center shaft portion, and the drilling can be performed reliably. In addition, the holding structure of the center shaft portion can be simplified, so that the punching tool itself can be reduced in size, and the handleability can be improved.

  According to the punching device of the second aspect, in addition to the effect of the first aspect, the center shaft portion can be rotated integrally with the main body with a simple configuration of a plate-like member, and the center shaft portion is It can be made to expand and contract between the first and second positions.

  According to the third aspect of the present invention, in addition to the effect of the second aspect, the plate-like member is extended from the bent state by its own elasticity, and the center shaft portion is returned from the second position to the first position. Therefore, it is not necessary to provide a separate elastic member, the total number of parts can be reduced, the assembly work efficiency can be improved, and the cost can be reduced.

  According to the punching tool of claim 4, in addition to the effect of claim 2 or 3, the plate-shaped member penetrates the main body, so that the overall structure can be made compact, and the stroke of the center shaft portion Can be secured greatly.

  According to the punching tool of claim 5, in addition to the effect of any one of claims 1 to 4, the center shaft portion does not penetrate the drilled body during drilling, and damages a device or the like in the drilled body. Can be reliably prevented.

  According to the punching tool of claim 6, in addition to the effect of claim 5, even when the thickness of the drilled body to be drilled is different, the protrusion length of the center shaft portion is changed in accordance with the thickness of the drilled body. Can be adjusted.

  According to the piercing tool of the seventh aspect, in addition to the effects of the first to sixth aspects, at the time of piercing, first, the abutting portion rotates and comes into contact with the drilled body, and the center shaft portion further drills into the drilled body. In addition to preventing the material from entering or penetrating the perforated body, the influence of friction such as frictional heat generated with the perforated body is absorbed.

  According to the punching tool according to the eighth aspect, in addition to the effect of the fourth aspect, it is possible to easily confirm that the center shaft portion has arrived at the second position by the adjustment screw coming into contact with the restriction piece. .

  According to the punching tool of claim 9, in addition to the effect of claim 4, the bent portion or the curved portion of the plate-shaped member abuts on the outer peripheral portion of the base portion of the main body, so that the center shaft portion is in the second position. It can be easily confirmed that it has arrived.

  According to the punching tool of the tenth aspect, the center shaft portion can be made non-rotating and extendable with respect to the main body with a simple structure without processing the center shaft portion, and as a result, inexpensively. Can be produced. In other words, by eliminating the processing of the center shaft portion, there is no core blurring of the center shaft portion, and the drilling can be performed reliably. In addition, the holding structure of the center shaft portion can be simplified, so that the punching tool itself can be reduced in size, and the handleability can be improved.

  According to the punching tool of the eleventh aspect, the center shaft portion can be prevented from rotating and retractable with respect to the main body with a simple structure without processing the center shaft portion. Can be produced. In other words, by eliminating the processing of the center shaft portion, there is no core blurring of the center shaft portion, and the drilling can be performed reliably. In addition, the holding structure of the center shaft portion can be simplified, so that the punching tool itself can be reduced in size, and the handleability can be improved.

  According to the punching tool of the twelfth aspect, in addition to the effect of any one of the first to eleventh aspects, the center shaft portion is guided by the guide hole of the connecting portion, and the axial movement of the center shaft portion is smoothed. be able to. Further, the center shaft portion rotates integrally with the main body in a state where the tip end side of the center shaft portion is held by the other end side of the holding member. That is, as compared with the prior art, the center shaft portion rotates integrally with the main body in a state where the distal end side is held. Therefore, the stability at the time of rotation of the center shaft portion is increased, and the core blur can be effectively prevented. At the same time, the base end side of the center shaft portion is inserted into the guide hole of the connecting portion of the main body so as to be slidable in the axial direction, and supported in a state in which movement in the radial direction is restricted by the guide hole of the connecting portion. . Therefore, the center shaft portion is supported on the main body at two points, that is, the base end side and the tip end side, and the stability at the time of rotation is further increased, thereby preventing the core blurring more effectively. Can do. In addition, since the center blur can be prevented, when the center shaft portion is rotated integrally with the main body, the outer peripheral surface of the base end side of the center shaft portion is the inner peripheral surface of the guide hole of the connecting portion. Therefore, the expansion / contraction operation (stroke operation) is not hindered and the expansion / contraction operation can be performed smoothly.

  Further, at this time, the center shaft portion can be used without being processed, and in this case, the base end side of the center shaft portion has a circular cross section when not processed. Therefore, compared to the case where the non-circular section is formed on the base end side of the center shaft portion as in the prior art, when the center shaft portion is expanded and contracted in the axial direction while rotating integrally with the main body. Even if the outer peripheral surface of the base end side of the center shaft portion is slightly pressed against the inner peripheral surface of the guide hole of the connecting portion, the circular peripheral surface of the cross section of the base end side is the corresponding circular peripheral surface of the guide hole of the connecting portion. The pressing force is evenly distributed in the radial direction, and no great resistance is generated between the center shaft portion and the guide hole of the connecting portion. As a result, the center shaft can be extended and contracted extremely smoothly. In particular, at this time, the portion where the center shaft portion is prevented from rotating with respect to the main body is the other end side of the holding member, and the portion where the center shaft portion is telescopic with respect to the main body is the base of the center shaft portion. The end side becomes a guide hole portion of the connecting portion inserted, and these become separate portions. Therefore, as compared with the case where the center shaft portion is prevented from rotating and expanding and contracting by the hole portion of the main body as in the prior art, the center axis direction is rotated while the center shaft portion is rotated integrally with the main body. When extending and contracting to the center shaft, there is no large resistance between the center shaft portion and the guide hole portion of the connecting portion of the main body in the direction of expansion and contraction of the center shaft. It can be carried out.

  According to the punching tool of claim 13, in addition to the effect of claim 12, even when the punched piece (piercing scrap) of the drilled body by the punching blade enters between the center shaft portion and the guide hole of the connecting portion. Since the guide hole is a through hole, the perforated piece can be smoothly discharged from the end opening opposite to the center shaft portion of the guide hole.

  According to the punching tool of the fourteenth aspect, in addition to the effect of any one of the first to thirteenth aspects, the drilling blade can have a simple configuration and the drilling efficiency can be improved.

  The best mode for carrying out the present invention (hereinafter referred to as an embodiment) will be described below. Throughout each embodiment, the same members, elements, or parts are denoted by the same reference numerals, and the description thereof is omitted.

Embodiment 1
FIG. 1 is an exploded perspective view showing a punching device according to Embodiment 1 of the present invention. FIG. 2 is a perspective view showing the punching tool according to Embodiment 1 of the present invention. FIG. 3 is a front view showing the left half part of the punching tool according to Embodiment 1 of the present invention in a cross-section and a part of the right half part broken away. FIG. 4 is a plan view showing the drilling tool according to Embodiment 1 of the present invention. FIG. 5 is a developed view showing a developed state of the drilling blade of the drilling tool according to Embodiment 1 of the present invention. FIG. 6 is an exploded perspective view showing the relationship between the holding member of the punch and the center drill according to Embodiment 1 of the present invention. FIG. 7 is a front view showing a state in which a roll pin is attached to the center drill of the drilling tool according to Embodiment 1 of the present invention. FIG. 8 is a perspective view showing a state in which a roll pin is attached to the center drill of the drilling tool according to Embodiment 1 of the present invention.

  The punching tool of Embodiment 1 is for drilling a perfect circular through hole in a drilled body such as a wall plate. As shown in FIGS. 1 and 2, the drilling tool according to Embodiment 1 includes main bodies 10, 20, a cutting blade 30, a center drill 40, and holding members 50, 60, 70, 80. Specifically, the main body 10 includes a substantially short cylindrical base portion 11 that opens at the lower end side, and a boss portion 12 that is integrally formed at the center of the base portion 11. The base 11 is formed integrally with an outer peripheral edge of a disk portion 11a having a substantially disk shape so that a short cylindrical flange portion 11b is suspended substantially orthogonally. Further, the boss portion 12 is erected upward in a state of being orthogonal to the center of the disk portion 11a. Further, as shown in FIG. 3, a mounting groove 11c extending from the lower end to the vicinity of the upper end is formed over the entire circumference of the flange portion 11b. On the other hand, a pair of left and right through-holes 13 are formed through the disk portion 11a at opposing positions on both the left and right sides of the boss portion 12. Each through-hole 13 has a substantially quadrangular shape extending from the vicinity of the boss portion 12 to the vicinity of the outer peripheral edge of the disk portion 11a. In addition, reinforcing ribs 14 are integrally formed on the upper surface of the disk portion 11a so as to extend in the front-rear and left-right directions. Further, a screw hole 15 penetrating the reinforcing rib 14 and the disk portion 11a is formed at a position behind the boss portion 12 in the reinforcing rib 14.

  As shown in FIG. 4, latching claws 16 are integrally formed in the mounting groove 11 c in the flange portion 11 b of the base portion 11 at a predetermined interval. In the first embodiment, the three latching claws 16 are arranged at a constant angular interval (120 degree interval). More specifically, each latching claw 16 has a substantially rectangular protrusion shape integrally formed on the lower end side of the mounting groove 11c of the flange portion 11b. A predetermined gap is provided between each latching claw 16 and the upper end of the mounting groove 11c of the flange portion 11b. A small hole 17 is formed through the flange portion 11b at a position facing the hooking claw 16 so that the hooking claw 16 in the mounting groove 11c can be visually recognized through the small hole 17. Further, in the flange portion 11b, a screw hole 18 penetrating from the upper surface of the flange portion 11b into the mounting groove 11c is formed at a position near the right side of the latching claw 16 located on the front (front side) right side. . A tapped screw 19 is screwed into the screw hole 18 so that the tip thereof protrudes into the mounting groove 11c.

  The boss portion 12 has a cylindrical shape, and a shaft body 20 composed of a hexagonal shaft is inserted and fixed therein. More specifically, the shaft body 20 has step portions 21 formed near the lower end and approximately the center. The shaft body 20 is mounted in a non-rotating state so that the lower end side of the shaft body 20 is closely fitted in the boss portion 12 and cannot be rotated in the circumferential direction around the shaft center. Further, at this time, the shaft body 20 has the stepped portion 21 closely fitted to the corresponding stepped portion of the boss portion 12 and cannot move in the axial direction. On the other hand, a guide hole 22 having a perfectly circular cross section is formed at the axial center position of the shaft body 20 and extends along the axial center. The guide hole 22 is a through hole that penetrates the entire axial length of the shaft body 20, and opens at both upper and lower ends of the shaft body 20. In the first embodiment, the shaft body 20 constitutes a connecting portion that can be connected to a rotating shaft (not shown) of a driving portion of the rotating tool. That is, the main body 10 is driven via the shaft body 20 to the rotating shaft (shaft) of the driving portion of the rotating tool by gripping the shaft body 20 as the connecting portion by the chuck portion of the rotating tool such as an electric drill. The main body 10 can be integrally rotated synchronously (forward / reverse rotation) via the shaft body 20 by rotating the rotation shaft of the drive unit of the rotation tool. The main body 10 can be integrally formed as a whole by using a predetermined synthetic resin material such as glass fiber reinforced polyamide resin (PA). The shaft body 20 can be insert-molded into the boss portion 12 when the main body 10 is molded.

  The cutting blade 30 as a whole has a substantially cylindrical shape having substantially the same diameter as the mounting groove 11c of the flange portion 11b, is mounted in the mounting groove 11c of the flange portion 11b, and rotates synchronously integrally with the main body 10. It is like that. More specifically, as shown in FIG. 5, the cutting blade 30 has a single rectangular saw blade shape. The overall length of the cutting blade 30 is slightly shorter than the entire circumference of the mounting groove 11c of the flange portion 11b. The cutting blade 30 is curved into a cylindrical shape corresponding to the mounting groove 11c of the flange portion 11b, and the upper end thereof When the part is mounted in the mounting groove 11c, an opening 31 extending in the entire vertical direction is formed at the front center. Further, the upper end of the cutting blade 30 is formed with a latching hole 32 at a position corresponding to the three latching claws 16 integrally formed in the mounting groove 11c of the flange 11b. That is, at the upper end of the cutting blade 30, three retaining holes 32 are formed at regular angular intervals (120 degree intervals). Each hooking hole 32 has a substantially bowl shape composed of a fitting part 32a and a hooking part 32b. And the cutting blade 30 is made into the said cylindrical shape, and the upper end of the cutting blade 30 is inserted in the mounting groove 11c of the flange part 11b in the state which made the latching hole 32 of the cutting blade 30 correspond to the latching claw 16 by the side of the main body 10. When moving upward as much as possible, first, the latching claws 16 are fitted into the fitting portions 32 a of the corresponding latching holes 32. When the main body 10 is rotated in the clockwise direction in FIG. 4 with respect to the cutting blade 30 from this state, each latching claw 16 moves from the fitting portion 32a of each corresponding latching hole 32 to the latching portion 32b. And is tightly fitted to the latching portion 32b. Thereby, the cutting blade 30 can be fixed to the flange portion 11 b of the main body 10. In addition, the fitting part 32a of the latching hole 32 is made into the left-right dimension which can insert the said latching claw 16, and the latching part 32b is made into the up-down dimension which can fit the latching claw 16 closely. Further, a large number of saw blades 33 are formed on the entire length of the lower end of the cutting blade 30. Each saw blade 33 can have an arbitrary saw blade shape, but the saw blade 34 located at the drilling start position at the time of drilling (at the time of cutting), that is, the saw blade 34 located on the right side of the opening 31 is covered. The inclined edge on the side of the opening 31 is inclined at an angle larger than that of the other saw blade 33 (for example, about 45 degrees) so as to make it easier to cut into the perforated body.

  Here, in a state where the cutting blade 30 is mounted in the mounting groove 11c of the flange portion 11b and fixed by the latching claw 16, a rotating tool is connected to the shaft body 20 of the main body 10, and the main body 10 is rotated by the rotating tool. When moved, the cutting blade 30 rotates integrally with the main body 10. At this time, the rotating shaft of the rotating tool rotates in the clockwise direction in FIG. 4 by its normal rotation, so the main body 10 also rotates in the clockwise direction, and the cutting blade 30 also rotates in the clockwise direction. Therefore, during rotation, the latching claw 16 on the main body 10 side is always urged in a direction in which the latching claw 16 is closely fitted in the latching portion 32 b of the latching hole 32 of the cutting blade 30. The cutting blade 30 is not detached from the mounting groove 11c of the flange portion 11b by separating from the stop hole 32. Further, the tap screw 19 is screwed into the screw hole 18 of the main body 10 in a state where the cutting blade 30 is mounted in the mounting groove 11 c of the flange portion 11 b and fixed by the latching claw 16. The shaft portion of the tap screw 19 protrudes into the mounting groove 11c of the flange portion 11b and is positioned in the fitting portion 32a of the fitting hole 32 of the cutting blade 30. Thereby, even when the rotating shaft of the rotating tool is rotated in the reverse direction and rotated counterclockwise in FIG. 4, the engaging portion 32b of the engaging hole 32 of the cutting blade 30 is biased from the engaging portion 32a. The tap screw 19 prevents the hooking claw 16 to be moved. Therefore, for example, when the saw blade 33 of the cutting blade 30 bites into the drilled body and the cutting blade 30 cannot be removed from the drilled body, the cutting blade 30 is drilled by rotating the rotating shaft of the rotating tool reversely. Although it may be necessary to remove from the body, even in this case, the latching claw 16 is not detached from the latching hole 32 of the cutting blade 30, and the cutting blade 30 is not dropped from the mounting groove 11c of the flange portion 11b. .

  Further, two discharge holes 35 and 36 having a concave shape larger than the valley shape between the saw blades 33 are formed at predetermined positions at the lower end of the cutting blade 30. One discharge hole 35 has a wide, substantially rectangular shape corresponding to a valley shape formed between the saw blades 33 on both the left and right sides by omitting (deleting) one saw blade 33. Further, the other discharge hole 36 has a substantially rectangular shape with a narrow width obtained by expanding the valley shape of two adjacent saw blades 33 to the left and right. Accordingly, saw blades 37 narrower than the saw blade 33 are formed on the left and right sides of the discharge hole 35. Note that only one of the discharge holes 35 and 36 can be provided in the cutting blade 30. Alternatively, other shapes of discharge holes can be formed in the cutting blade 30. Alternatively, the cutting blade 30 can be entirely formed with the saw blade 33 without providing a discharge hole. Here, the discharge holes 35 and 36 are for discharging a chip-like cutting piece coming out of the drilled body from the inside of the cutting blade 30 to the outside when the drilled body is drilled by the cutting blade 30. . In the first embodiment, the cutting blade 30 extends from the main body 10 in parallel with the axial direction (axial center) of the main body 10 and is integrated with the main body 10 so as to drill a through hole in the drilled body. A rotating drilling blade is formed.

  The upper end of the center drill 40 is inserted into the inside from the lower end opening of the guide hole 22 of the shaft body 20 fixed to the boss portion 12 of the main body 10. The holding portions 50, 60, 70, 80 include a plate spring 50 as a pair of left and right plate members, a pair of front and rear upper holders 60 that hold the upper ends of the plate springs 50, and the plate springs 50. It has a pair of front and rear lower holders 70 that hold the lower end portion, and a substantially cylindrical roll pin 80 that is housed in the lower holder 60 and holds the lower end portion of the center drill 40. The left and right leaf springs 50 have a bent portion 51 at the center, and are bent outward (left and right) at the bent portion 51, respectively. In addition, the leaf spring 50 has a mounting shaft 52 integrally formed at both upper and lower ends. The mounting shaft 52 protrudes from both sides of the leaf spring 50 in the width direction. The leaf spring 50 can be integrally formed of a synthetic resin material such as polyoxymethylene resin (POM). In addition, the leaf | plate spring 50 can also integrally form the linear rib extended in the up-down direction substantially whole in the center of the width direction. Thus, the spring strength (spring elasticity) of the leaf spring 50 can be adjusted by adjusting the width and height (projection height) of the rib. On the other hand, in the first embodiment, the upper holders 60 having the same configuration are joined to each other so as to form a pair in the front and rear, and the shaft body 20 is sandwiched between the upper holders 60. Further, the lower holders 70 having the same configuration are joined to each other so as to form a pair in the front and rear, and the tip portion of the center drill 40 is sandwiched between the lower holders 70 via the roll pins 80. Further, at this time, the upper mounting shaft 52 of the pair of left and right leaf springs 50 is supported between the pair of front and rear upper holders 60 and the lower side of the pair of left and right leaf springs 50 is interposed between the pair of front and rear lower holders 70. The mounting shaft 52 is pivotally supported.

  Specifically, first, in Embodiment 1, two pieces of the same configuration are used as the pair of front and rear upper holders 60. Each upper holder 60 has a substantially rectangular block shape extending in the left-right direction, and a stepped groove 61 extending in the entire vertical direction is formed at the left-right center on the inner surface side (opposing surface side). Further, the stepped groove 61 of the upper holder 60 has an inner surface shape that matches the step portion 21 of the shaft body 20 and the front half or the rear half of the upper and lower side portions thereof. Then, by joining the upper holders 60 so as to make a pair in front and rear, through the stepped grooves 61 of both the upper holders 60, a through hole having a stepped hole shape that matches the stepped portion 21 portion of the shaft body 20 is formed. The Accordingly, when the stepped portion 21 portion of the shaft body 20 is sandwiched from the front and rear by the pair of front and rear upper holders 60, the stepped portion 21 portion of the shaft body 20 is closely fitted between the stepped grooves 61 (through holes) of both the upper holders 60. Held in. In addition, on both the left and right sides of each upper holder 60, a notch 62 having a thickness about half that of the upper holder 60 is formed. Furthermore, a shaft support hole 63 into which the upper mounting shaft 52 of the leaf spring 50 is rotatably inserted is formed on the upper end side of each notch 62 so as to extend in the thickness direction. Furthermore, an insertion hole 64 and an insertion hole 65 are formed in the portion between the stepped groove 61 and the notches 62 of the upper holder 60 so as to penetrate in the thickness direction. The insertion hole 64 includes a large-diameter portion that accommodates the head of the screw 66 and a small-diameter portion that penetrates the proximal half of the shaft portion of the screw 66. The insertion hole 65 includes a large-diameter portion that accommodates the hexagon nut 67 in a non-rotating state, and a small-diameter portion that passes through the tip half of the shaft portion of the screw 66. And the direction which mutually opposes the large diameter hole part of each insertion hole 64 of a pair of upper holder 60 in the state which clamped the step part 21 part of the shaft body 20 between the stepped groove | channels 61 of a pair of upper holder 60. The heads of the pair of screws 66 are accommodated and held, the shaft portions of the screws 66 are inserted into the small diameter hole portions of the insertion holes 64, and the shaft portions of the screws 66 are inserted into the insertion holes of the counterpart upper holder 60. The pair of front and rear upper holders 60 can be fastened and joined to each other by being inserted into the small-diameter hole portion 65 and screwed into the hexagon nut 67 accommodated in the large-diameter hole portion of the insertion hole 65. Further, the upper holder 60 can be firmly fitted on the outer periphery of the shaft body 20 and fixed to the shaft body 20 so as to prevent rotation about the shaft and not to move up and down along the shaft.

  As shown in FIG. 6, in Embodiment 1, two pieces of the same configuration are used as the pair of front and rear lower holders 70. Like the upper holder 60, each lower holder 70 has a substantially rectangular block shape extending in the left-right direction, and a stepped groove 71 extending in the entire vertical direction is formed in the left-right center on the inner surface side (opposing surface side). The stepped groove 71 of the lower holder 70 has an inner shape in which the upper end portion is a small-diameter semicircular hole, the central portion and the lower end portion are large-diameter semicircular holes, and the semicircular holes are arranged coaxially. Have. Then, by joining the lower holder 70 to each other so as to form a pair in front and rear, a stepped hole-shaped through hole is formed by the stepped groove 71 of both the lower holders 70. In addition, on the upper end sides of the left and right sides of each lower holder 70, a notch 72 having a half thickness is formed. Further, a shaft support hole 73 into which the lower mounting shaft 52 of the leaf spring 50 is rotatably inserted is formed at the approximate center of each notch 72 so as to extend in the thickness direction. Furthermore, an insertion hole 74 and an insertion hole 75 having the same configuration as the insertion hole 64 and the insertion hole 65 of the upper holder 60 are formed in a portion between the stepped groove 71 and the notches 72 of the lower holder 70. It is formed penetrating in the thickness direction. That is, the insertion hole 74 includes a large-diameter portion that accommodates the head portion of the screw 76 and a small-diameter portion that passes through the proximal half of the shaft portion of the screw 76. The insertion hole 75 includes a large-diameter portion that accommodates the hexagon nut 77 in a non-rotating state, and a small-diameter portion that passes through the tip half of the shaft portion of the screw 76. In addition, a small protrusion-like restricting piece 78 protruding substantially orthogonal to the outer surface is integrally formed at the center (between the insertion hole 74 and the insertion hole 75) on the outer surface side of the lower holder 70. The upper holder 60, the lower holder 70, and a synthetic resin material such as polyoxymethylene resin (POM) can be integrally formed.

  On the other hand, as shown in FIGS. 7 and 8, the cylindrical roll pin 80 has a sleeve shape, is cut along a central position in the circumferential direction (for example, the front position), and extends in the entire vertical direction. A split groove 81 is formed. The opposing edge of the split groove 81 portion of the roll pin 80 may be a sawtooth or wave-shaped edge that meshes with each other as shown in FIG. 7, or a simple linear edge as shown in FIG. It is good also as an edge. The roll pin 80 is closely fitted and held at a position spaced a predetermined distance from the tip of the center drill 40, and in this state, the roll pin 80 is formed in the large-diameter hole portion of the stepped groove 71 of the pair of front and rear lower holders 70. It is tightly fitted and pressed. That is, the roll pin 80 is inserted from the front end of the center drill 40 and fitted with the predetermined protrusion length left at the front end of the center drill 40. At this time, if the inner diameter of the roll pin 80 is set slightly smaller than the outer diameter of the center drill 40, the roll pin 80 can be held by the center drill 40 by the elasticity of the split groove 81. And in the state which pinched the front-end | tip part of the center drill 40, and the roll pin 80 between the stepped groove | channel 71 of a pair of lower holder 70, it opposes each other at the large diameter hole part of each penetration hole 74 of a pair of lower holder 70. The heads of the pair of screws 76 are accommodated and held from the direction, the shaft portions of the screws 76 are inserted into the small-diameter hole portions of the insertion holes 74, and the shaft portions of the screws 76 are inserted into the counterpart lower holder 70. The pair of front and rear lower holders 70 can be fastened and joined to each other by being inserted into the small diameter hole portion of the hole 75 and screwed into the hexagon nut 77 accommodated in the large diameter hole portion of the insertion hole 75. . This also allows the roll pin 80 to be clamped between the pair of front and rear lower holders 70 so that the center drill 40 can be held via the roll pin 80 in a non-rotating state with the axis as the center.

  At this time, the roll pin 80 has an outer diameter slightly larger than the lower large-diameter hole portion of the stepped hole-shaped through holes formed by the stepped grooves 71 of the lower holders 70, With the pinching by 70, the roll pin 80 is pressed inward by the peripheral surface of the stepped groove 71, and the center drill 40 is pressed and held via the roll pin 80. As a result, the roll pin 80 can be firmly held between the lower holders 70 in a detent state around the axis, and the center drill 40 can be firmly held via the roll pin 80 in a detent state around the axis. can do. Further, the roll pin 80 is not displaced in the axial direction with respect to the stepped groove 71 of the lower holder 70, and the center drill 40 is not displaced in the axial direction with respect to the roll pin 80. And thereby, the center drill 40 can be integrally rotated via the upper holder 60, the leaf | plate spring 50, the lower holder 70, and the roll pin 80 synchronizing with rotation of the main body 10 by a rotation tool. . At this time, the length of the roll pin 80 is such that the upper end thereof is in contact with the stepped portion of the stepped groove 71 of the lower holder 70 (the boundary line between the small diameter hole and the large diameter hole), and the lower end is from the lower surface of the lower holder 70. The length is set to slightly protrude downward. In this way, when the center drill 40 is drilled into the body to be drilled for a predetermined length (the protruding length), the tip (lower end) of the roll pin 80 comes into contact with the surface of the body to be drilled, and the center drill 40 is further moved to the body to be drilled. To prevent penetration. At this time, the roll pin 80 absorbs the influence (friction heat, etc.) caused by the friction with the drilled body due to the rotation of the center drill 40, and effectively exerts the direct influence caused by the friction on the lower holder 70. To prevent. Therefore, the roll pin 80 is preferably made of metal such as carbon tool steel from the viewpoint of strength, heat resistance, durability, and the like. In the first embodiment, the protruding length of the tip of the center drill 40 held by the lower holder 70 of the holding portion from the lower holder 70, more precisely, the protruding length from the tip of the roll pin 80 is the center. It is preferable to set the thickness to be less than the thickness of the drilled body so that the drill 40 does not penetrate the drilled body. The protrusion length of the tip of the center drill 40 held by the lower holder 70 of the holding part via the roll pin 80 varies in thickness by changing the holding position of the center drill 40 by the roll pin 80 in the axial direction. It can be freely changed according to the thickness of the drilled body.

  Here, the relative positional relationship between the cutting blade 30 and the center drill 40 and the roll pin will be described. In the first embodiment, the tip of the roll pin 80 is in the released state where no external force is applied to the leaf spring 50. It is located on substantially the same plane as the tip, and the tip of the center drill 40 protrudes from the tip of the cutting blade 30 by the protruding length. In this way, when the center drill 40 is drilled into the drilled body and the tip of the roll pin 80 comes into contact with the surface of the drilled body, the cutting blade 30 starts drilling the drilled body. However, in a released state where no external force is applied to the leaf spring 50, the tip of the roll pin 80 is positioned to protrude outward from the tip of the cutting blade 30, and the tip of the center drill 40 protrudes from the tip of the cutting blade 30 by the protrusion length or more. You can also do it. In this way, when the center drill 40 is drilled into the body to be drilled and the tip of the roll pin 80 comes into contact with the surface of the body to be drilled, the cutting blade 30 is still separated from the front of the body to be drilled. Further, when the cutting blade 30 is advanced toward the drilled body by a predetermined distance (projection distance of the roll pin 80 from the cutting blade 30), the cutting blade 30 starts drilling of the drilled body. Or, conversely, in a released state where no external force is applied to the leaf spring 50, the tip of the roll pin 80 is located inwardly from the tip of the cutting blade 30, and the tip of the center drill 40 extends from the tip of the cutting blade 30. It is also possible to project less than the projecting length. In this way, the center drill 40 is drilled into the drilled body, and the cutting blade 30 starts drilling the drilled body before the tip of the roll pin 80 comes into contact with the surface of the drilled body. In any case, before the cutting blade 30 starts drilling of the drilled body, the center drill 40 drills into the center position and performs center positioning. Therefore, the cutting blade 30 smoothly drills the drilled body. Can be done.

  In the first embodiment, the center drill 40 is extended from the main body 10 in the opposite direction to the shaft body 20 at the same position as the shaft body 20 as the connecting portion, and the cutting blade 30 as the drilling blade is provided. A substantially rod-shaped center shaft portion serving as a rotation center is configured. The leaf spring 50, the upper holder 60, the lower holder 70, and the roll pin 80 are attached to one end side of the main body in a detent state around the shaft, and the other end side serves as a center shaft portion as the center shaft portion. A holding member is configured to hold the drill 40 in a non-rotating state around the axis so that the center drill 40 rotates together with the main body 10 around the axis. Furthermore, the roll pin 80 of the holding member constitutes a contact portion that holds the center drill 40 in a state where the tip end portion of the center drill 40 protrudes by a predetermined length (the protruding length).

Operation and Effect Next, the usage method, operation and effect of the punching tool according to Embodiment 1 will be described. FIG. 9 shows a drilling operation of the drilled body by the drilling tool according to Embodiment 1 of the present invention, (a) is a cross-sectional view showing the center drill positioned at the drilled body, and (b) is a drilling blade. It is sectional drawing which shows the state which perforated the to-be-pierced body by.
The punching tool according to the first embodiment is used for drilling a circular or daruma-shaped through-hole in a wall material so that a device such as a wiring box arranged inside a building wall or the like faces indoors. Is done. First, for example, when the opening of a wiring box disposed on the back of the wall is faced to the front side of the wall, the operator can connect the wiring box (illustrated) disposed inside the wall material W (wall plate) as the perforated body. Is detected using a dedicated detection device (not shown), and the position of the detection is determined. Next, a rotating shaft of a rotating tool such as an electric tool is connected to the shaft body 20 of the main body 10. Next, the center position where the center drill 40 is to be inserted is determined at the detected position of the wiring box, and the tip of the center drill 40 is brought into contact with the center position as shown in FIG. The rotation axis of the rotation tool is rotated forward (rotated clockwise in FIG. 4), and the main body 10 is rotated forward via the shaft body 20. Then, the center drill 40 rotates positively integrally with the main body 10 via the upper holder 60, the leaf spring 50, the lower holder 70 and the roll pin 80. At this time, since the cutting blade 30 is also mounted and fixed in the mounting groove 11c of the flange portion 11b, the cutting blade 30 rotates positively integrally with the main body 10. At the same time, when the turning tool is pressed toward the wall material W and the center drill 40 is pressed toward the wall material W through the main body 10, the center drill 40 is drilled into the wall material W at the center position. Enter. Then, as shown in FIG. 9B, when the center drill 40 penetrates the wall material W by a predetermined length (projection length), the tip of the roll pin 80 comes into contact with the surface of the wall material W. Thereby, the center drill 40 does not penetrate further into the wall material W, and the center drill 40 idles with respect to the wall material W in the penetration state. At substantially the same time, the cutting blade 30 starts drilling the wall material W with the saw blades 33, 34, and 37.

  Here, as described above, the holding members 50, 60, 70, 80 are elastic by the leaf spring 50, and are always at the first position where the tip of the center drill 40 protrudes from the tip of the cutting blade 30. The center drill 40 is urged in a direction (first axial direction) from the proximal end side to the distal end side until (the center drill distal end position in FIG. 9A). Further, the holding members 50, 60, 70, 80 are configured so that the tip of the center drill 40 has the cutting blade 30 in accordance with an external force in a direction (second axial direction) from the tip side to the base side of the center drill 40. The center drill 40 is allowed to elastically contract in the axial direction against the elasticity of the leaf spring 50 up to the second position (the center drill tip position in FIG. 9B) that is recessed from the tip of the center. Furthermore, the holding members 50, 60, 70, 80 are leaf springs 50 as a pair of plate-like members extending between one end side (upper holder 60 side) and the other end side (lower holder 70 side). The upper holder 60 on one end side of the leaf spring 50 is attached to the main body 10 in a non-rotating state, and the center drill 40 is held in a non-rotating state by the lower holder 70 on the other end side of the leaf spring 50. Further, the leaf spring 50 is formed between the one end side and the other end side of the holding members 50, 60, 70, 80 so that the center drill 40 can expand and contract between the first position and the second position. It can be bent or bent between. Note that at least one pair of leaf springs 50 may be provided, and two or more pairs may be provided. Furthermore, the leaf spring 50 always has its own elasticity for extending to the maximum length between one end side and the other end side of the holding members 50, 60, 70, 80, and the center in the extended state. The drill 40 is biased to the first position, and elastically bent or bent from the extended state in response to the center drill 40 retracting (contracting) from the first position to the second position. To do. Further, the main body 10 has a substantially plate-like base portion 11 on which the cutting blade 30 is disposed on the outer periphery, and has a shaft body 20 that is integrally fixed to one side in the thickness direction of the base portion 11 as a connecting portion. ing. Further, the one end side of the leaf spring 50 is fixed to the shaft body 20 via the upper holder 60, penetrates the base portion 11 in the thickness direction via the through hole 13, and the lower holder 70 and the roll pin on the other end side. The center drill 40 is fixed by 80. Furthermore, the main body 10 has a guide hole 22 extending in the axial center direction of the shaft body 20 as the connecting portion, and the center drill 40 is held at its distal end side in a non-rotating state by the upper holder 60 of the holding portion. At the same time, the base end side of the center drill 40 is inserted into the guide hole 22, whereby the expansion / contraction operation of the center drill 40 between the first position and the second position is guided by the guide hole 22 of the main body 10.

  Therefore, as described above, the leaf spring is from the time when the center drill 40 is centered on the wall material W to the time when the center drill 40 penetrates the wall material W and the tip of the roll pin 80 contacts the wall material W. 50 is in an extended state (a state where no external force is applied) shown in FIG. 9A due to its spring elasticity, and the center drill 40 is in the first position with respect to the cutting blade 30. Then, when the rotating tool is further pressed toward the wall material W and the cutting blade 30 is further pressed toward the wall material W via the main body 10, the cutting blade 30 cuts the wall material W while cutting the wall material W. Penetration inside the material W. At this time, with the penetration of the cutting blade 30 into the wall material W, the lower holder 70 approaches the upper holder 60 via the roll pin 80, and the leaf spring 50 resists its own elasticity to bend the bent portion 51. It bends or curves and contracts. That is, the cutting blade 30 penetrates into the wall material W in a form that resists the elasticity of the leaf spring 50. At this time, the center drill 40 moves from the distal end side of the guide hole 22 of the shaft body 20 toward the proximal end side of the center drill 40. When the cutting blade 30 penetrates the wall material W, the center drill 40 is in the second position with respect to the cutting blade 30, and the cutting blade 30 penetrates the wall material W to form a through hole in the wall material W. When drilled, the lower holder 70 is separated from the upper holder 60 by the elasticity (biasing force) of the leaf spring 50, and the center drill 40 returns to the first position. In this way, when the through hole is formed in the wall material W, the main body 10 is pulled toward the front side through the rotating tool, and the cutting blade 30 is separated from the wall material W. Then, the circular cut portion of the wall material W remaining in the cutting blade 30 so that the center drill 40 holds the center is pulled out from the center drill 40 and removed. Thereafter, similarly, drilling is performed at an arbitrary position of the wall material W.

  As described above, according to the drilling tool according to the first embodiment, the center shaft portion of the center drill 40 or the like rotates around the main body 10 with a simple structure without processing the center shaft portion of the center drill 40 or the like. As a result, the whole can be manufactured at low cost. In particular, when the wall material W is drilled by the cutting blade 30, fine cutting pieces (cutting scraps) of the wall material W are scattered in the cutting blade 30, and the center drill 40 has a substantially closed space in the cutting blade 30. The base end side may enter a gap between the base end side outer peripheral surface of the center drill 40 and the inner peripheral surface of the guide hole 22 of the shaft body 20. And if this cutting piece accumulates in the clearance gap between the center drill 40 and the shaft body 20, the movement in the guide hole 22 of the shaft body 20 of the center drill 40 may have a bad influence. However, in the first embodiment, the guide hole 22 of the shaft body 20 is provided through the shaft body 21. Therefore, the cutting piece that has entered the guide hole 22 of the shaft body 20 from the center drill 40 can be smoothly discharged from the upper end opening of the guide hole 22 of the shaft body 20, thereby preventing adverse effects on the movement of the center drill 40. be able to. Moreover, the cutting pieces scattered in the cutting blade 30 can be efficiently discharged to the outside from the discharge holes 35 and 36 provided in the cutting blade 30. In addition, when the saw blades 33, 34, 37 of the cutting blade 30 have bitten into the wall material W and cannot be rotated, etc. It is necessary to reversely rotate the main body 10 with a tool. However, even in this case, the tap screw 19 comes into contact with the peripheral edge of the retaining hole 32 of the cutting blade 30, the retaining hole 32 is detached from the retaining claw 16, and the cutting blade 30 is removed from the mounting groove 11 c of the main body 10. Ensure that it will not fall out.

  Further, the center drill 40 determines the length of protrusion of the tip of the center drill 40 held by the lower holder 70 of the holding portion from the lower holder 70, more precisely the length of protrusion from the tip of the roll pin 80. If the thickness is set to be less than the thickness of the wall material W so as not to penetrate the wall material W, the center drill 40 will not penetrate the wall material W and damage the wiring box in the wall and various parts in the wiring box. It is possible to completely prevent the trouble of doing. Furthermore, the protruding length of the tip of the center drill 40 held by the lower holder 70 of the holding part via the roll pin 80 can be changed in accordance with the thickness of the wall material W having a different thickness. Therefore, the protrusion length can be set so that the center drill does not penetrate the wall material W as described above even for various wall materials W having different thicknesses. Further, the holding member further has a roll pin 80 as the contact portion, and when the center drill 40 is made to penetrate the predetermined length (projection length) into the wall material W during center positioning, the tip of the roll pin 80 is The center drill 40 is brought into contact with the surface of the wall material W while being rotated to prevent further penetration of the center drill 40, and the center drill 40 is moved to the second position against the elasticity of the leaf spring 50 of the holding member. Can be moved backwards. At this time, the roll pin 80 abuts against the surface of the wall material W while rotating to prevent the friction from affecting the lower holder 70 and the like. Further, the cutting blade 30 has a saw blade shape continuous in the circumferential direction of the main body 10 by bending one saw blade into a substantially cylindrical shape. Therefore, it is possible to provide an inexpensive cutting blade 30 with a simple configuration using a single saw blade, and it is possible to efficiently cut a body to be drilled such as the wall material W. In the first embodiment, the plate spring 50 having elasticity itself is used as the plate-like member, but a plate-like member that does not have elasticity and is simply bent or curved is used, and is elasticized by a separate elastic member. May be given.

  In addition, in the first embodiment, the main body 10 has the guide hole 22 extending in the axial direction of the shaft body 20 as the connecting portion, and the center drill 40 as the center shaft portion has the tip side other than the holding member. While being held in a non-rotating state by the lower holder 70 on the end side and rotated integrally with the main body 10, its base end side is slidable in the axial direction in the guide hole 22 of the shaft body 20. Inserted and supported in a state in which movement in the radial direction is restricted by the guide hole 22 of the front shaft body 20, and expansion and contraction operation between the first position and the second position of the center drill 40 by the guide hole 22 of the shaft body 20. Will be guided. Therefore, the center drill 40 can be guided by the guide hole 22 of the shaft body 20, and the axial movement of the center drill 40 can be smoothed. Further, the center drill 40 rotates integrally with the main body 10 in a state where the tip end side of the center drill 40 is held by the lower holder 70 on the other end side of the holding member. That is, as compared with the prior art, the center drill 40 rotates integrally with the main body 10 in a state where the distal end side is held. Therefore, the stability at the time of rotation of the center drill 40 increases, and the core blur can be effectively prevented. At the same time, the base end side of the center drill 40 is inserted into the guide hole 22 of the shaft body 20 of the main body 10 so as to be slidable in the axial direction, and movement in the radial direction is restricted by the guide hole 22 of the shaft body 20. Supported by Therefore, the center drill 20 is supported by the shaft body 20 and the lower holder 70 at two points (two locations) on the base end side and the tip end side with respect to the main body 10, and stability during rotation. Is further increased, and core blurring can be more effectively prevented. Further, since the center blur can be prevented, when the center drill 40 is expanded and contracted in the axial direction while rotating integrally with the main body 10, the outer peripheral surface of the base end side of the center drill 40 is the guide hole 22 of the shaft body 20. There is no hindrance to the expansion / contraction operation (stroke operation) by being pressed against the inner peripheral surface, and the expansion / contraction operation can be performed smoothly.

  Furthermore, at this time, the center drill 40 can be used without being processed. In this case, the base end side of the center drill 40 has a circular cross section when not processed. Therefore, when the center drill 40 is expanded and contracted in the axial direction while rotating integrally with the main body 10 as compared with the case where the cross-sectional non-circular portion is formed on the proximal end side of the center drill as in the prior art. Even if the outer peripheral surface of the base end side of the center drill 40 is somewhat pressed against the inner peripheral surface of the guide hole 22 of the shaft body 20, the circular peripheral surface of the base end side corresponds to the guide hole 22 of the shaft body 20. The circular peripheral surface is pressed, and the pressing force is evenly distributed in the radial direction, so that no great resistance is generated between the center drill 40 and the guide hole 22 of the shaft body 20. As a result, the expansion / contraction operation of the center drill 40 can be performed extremely smoothly. In particular, at this time, the portion that prevents the center drill 40 from rotating with respect to the main body 10 is the lower holder 70 on the other end side of the holding member, and the portion that allows the center drill 40 to expand and contract with respect to the main body 10 is The guide hole 22 portion of the shaft body 20 into which the proximal end side of the center drill 40 is inserted becomes a separate portion. Therefore, as compared with the case where the center drill is prevented from rotating and extending and retracting by the hole portion of the main body as in the prior art, the center direction of the center drill 40 is rotated while integrally rotating with the main body 10. When the center drill 40 is expanded or contracted, a large resistance is not generated between the center drill 40 and the guide hole 22 portion of the shaft body 20 of the main body 10 in the expansion / contraction direction of the center drill 40, and the expansion / contraction operation (stroke operation) of the center drill 40 is performed. Can be performed very smoothly.

Embodiment 2
FIG. 10 is a cross-sectional view showing the punch according to the second embodiment of the present invention as viewed from the right side.
The punching tool according to Embodiment 2 is the punching tool according to Embodiment 1, in which the adjustment screw 101 is screwed into the screw hole 15 of the main body 10, and the tip of the shaft portion (the lower end in FIG. 10) is It comes into contact with the regulating piece 78 of the lower holder 70. That is, the punching tool according to Embodiment 2 is further screwed into the screw hole 15 of the base 11 of the main body 10 and penetrates the base 11, and the lower part on the other end side of the holding members 50, 60, 70, 80. An adjustment screw 101 extending toward the restriction piece 78 of the holder 70 is provided. When the holding members 50, 60, 70, 80 are in the second position, they are provided in the lower holder 70 on the other end side of the holding members 50, 60, 70, 80 and face the tip of the adjustment screw 101. The tip of the adjustment screw 101 comes into contact with the restricting piece 78 arranged so that the center drill 40 is prevented from further retracting from the second position. The other configuration is the same as that of the first embodiment. Specifically, in the drilling tool according to the second embodiment, the adjustment screw 101 is screwed into the screw hole 15 of the main body 10 and fixed at that position so that the adjustment screw 101 protrudes into the main body by a predetermined depth. To do. For example, as shown by the solid line in FIG. 10, the adjustment screw 101 can be fixed in a state where the entire length of the adjustment screw 101 protrudes into the main body 10, but in actual use, the adjustment screw 101 shown in FIG. The adjustment screw 101 is fixed in a state where the adjustment screw 101 is partially screwed into the screw hole 15 of the main body 10 so that the tip of the adjustment screw 101 is positioned at the position of the regulation piece 78 at the position 2 as shown by a two-dot chain line in FIG. Is done.

  In the second embodiment, when the drilled body is drilled, the roll pin 80 comes into contact with the drilled body, the center drill 40 and the lower holder 70 are retracted, and the center drill 40 is in the second position. The distal end abuts on the restriction piece 78 of the lower holder 70 to restrict further movement of the center drill 40. Therefore, in addition to the operation and effect of the first embodiment, the drilling tool according to the second embodiment can surely recognize that the center drill 40 has come to the second position. The person can confirm that the cutting blade 30 has completed the drilling of the drilled body. Therefore, despite the completion of drilling by the cutting blade 30, it is possible to reliably prevent the cutting blade 30 from being further advanced into the wall and damaging the wiring box or the like by the cutting blade 30. Further, the retraction length (shrinkage length) from the tip of the cutting blade 30 at the second position of the center drill 40 is adjusted by adjusting the depth (projection length) of the adjustment screw 101 into the main body 10. The immersion length (retraction amount) of the tip of the center drill 40 relative to the tip of the cutting blade 30 can be adjusted according to the thickness of the drilled body.

Embodiment 3
FIG. 11 shows a drilling operation of the drilled body by the drilling tool according to the third embodiment of the present invention, (a) is a cross-sectional view showing the center drill positioned at the drilled body, and (b) is a drilling blade. It is sectional drawing which shows the state which perforated the to-be-pierced body by.
The punching tool according to the third embodiment has substantially the same configuration as the punching tool according to the first embodiment. On the other hand, in the punching tool according to the third embodiment, the holding member has a pair of leaf springs 250 having a configuration in which the upper and lower attachment shafts 52 are omitted from the leaf spring 50 of the first embodiment. Each leaf spring 250 has a bent portion 251 at the center in the length direction, like the leaf spring 50. The upper and lower ends 252 of the pair of leaf springs 250 are fixed to the upper holder 60 and the lower holder 70 by fasteners 269 and 279 such as screws and bolts, respectively. The other configuration is the same as that of the punch according to the first embodiment. When the center drill 40 is moved from the first position (the state shown in FIG. 11A) to the second position (the state shown in FIG. 11B), the punching tool according to Embodiment 3 The bent portion comes into contact with the outer peripheral edge of the through hole 13 of the main body 10. That is, when the center drill 40 is in the second position, the bent portion 251 of the leaf spring 250 comes into contact with the outer peripheral edge of the through hole 13 of the base portion 11 of the main body 10, and the leaf spring 250 is further bent or The bending is prevented and the center drill 40 is prevented from further retracting from the second position. Therefore, in addition to the operation and effect of the first embodiment, the drilling tool according to the third embodiment can surely recognize that the center drill 40 has come to the second position. The person can confirm that the cutting blade 30 has completed the drilling of the drilled body. Therefore, despite the completion of drilling by the cutting blade 30, it is possible to reliably prevent the cutting blade 30 from being further advanced into the wall and damaging the wiring box or the like by the cutting blade 30.

FIG. 12 is a cross-sectional view showing a process when the plate-like member of the holding member of the punching tool according to Embodiment 3 of the present invention is elastically deteriorated.
In the punching tool according to Embodiment 3, when the plate spring 250 as the plate-like member of the holding member is elastically deteriorated, the elastic force of the plate spring 250 is reduced, so that the extension force of the holding member by the plate spring 250 is reduced. To do. Therefore, the center drill 40 cannot return to the first position shown in FIG. 11A, the tip of the roll pin 80 is immersed inward from the tip of the cutting blade 30, and the tip of the center drill 40 is The protrusion protrudes from the cutting blade 30 with a protrusion length less than a predetermined protrusion length. Therefore, in this case, as indicated by arrows in FIG. 12, the operator presses the bent portions 251 of the two leaf springs 250 inward with fingers or the like. Then, the center drill 40 can be extended and returned to the original first position indicated by a broken line in FIG. In this state, the intended drilling operation can be performed reliably in the same manner as described above. Needless to say, such processing can also be performed by the punch according to the first embodiment.

Embodiment 4
FIG. 13 is a plan view showing a punching tool according to Embodiment 4 of the present invention. 14 is a cross-sectional view taken along line AA in FIG.
As shown in FIGS. 13 and 14, the drilling tool according to Embodiment 4 includes main bodies 310 and 20, a cutting blade 30, a center drill 40, and holding members 350, 360, 370 and 80. Specifically, the main body 310 includes a substantially short cylindrical base 311 that opens at the lower end side, and a cylindrical boss 312 that is integrally formed at the center of the base 311. The base 311 is formed by integrally forming a short cylindrical flange portion 311b so as to hang substantially orthogonally to the outer peripheral edge of a disc portion 311a having a substantially disc shape. Further, the boss portion 312 is erected upward in a state of being orthogonal to the center of the disk portion 311a. Furthermore, a mounting groove 311c extending from the lower end to the vicinity of the upper end is formed over the entire circumference of the flange portion 311b. The cutting blade 30 is mounted and fixed in the mounting groove 311c of the base 311 in the same manner as in the first embodiment. Further, the shaft body 20 is inserted and fixed to the boss portion 312 as in the first embodiment. The center drill 40 has an upper end inserted into the guide hole 22 of the shaft body 20 fixed to the boss 312 of the main body 310.

  On the other hand, in the fourth embodiment, the holding member includes a holder 350, a support plate 360, a guide shaft 370, and the roll pin 80. The holder 350 can be configured similarly to the lower holder 70 of the first embodiment, and the pair of front and rear holders 350 hold the tip of the center drill 40 via the roll pins 80 and hold it in a non-rotating state. It is like that. The support plate 360 has a disk shape that is integrally formed so as to protrude horizontally on the outer circumferences of the holders 350. In the fourth embodiment, three guide shafts 370 are erected and fixed on the upper surface in the vicinity of the outer periphery of the support plate 360 at predetermined angular intervals (120 degree intervals) in the circumferential direction, and are parallel to the center drill 40. It extends vertically upward. Each guide shaft 370 is integrally formed in the vicinity of the axial center of the shaft portion 371, a shaft portion 371 having a cylindrical bar shape, a flange-shaped or disk-shaped upper locking portion 372 formed integrally with the upper end of the shaft portion 371. A lower locking portion 373.

  A circular small hole 311 d that passes through the shaft portion 372 is formed at a position facing the guide shaft 370 in the disk portion 311 a of the base portion 311. The shaft portion 371 of the guide shaft 370 is inserted into the small hole 311d of the disk portion 311a from below so as to be slidable up and down in the small hole 311d. Furthermore, at the first position of the center drill 40, the upper locking portion 372 of the guide shaft 370 is brought into contact with and locked to the upper surface of the disk portion 311a of the base portion 311 and at the second position of the center drill 40, The lower locking portion 373 is brought into contact with the lower surface of the disk portion 311a of the base portion 311 so as to be locked. Furthermore, a pressing (extension) coil spring 380 is interposed between the lower end of the boss portion 312 and the upper end of the holder 350 in a state of being externally mounted on the center drill 40. In the fourth embodiment, the holder 350, the support plate 360, the guide shaft 370, and the roll pin 80 are attached to one end side with respect to the main body 310 in a non-rotating state, and the center drill 40 is prevented from rotating by the other end side. The holding member is configured so that the center drill 40 rotates integrally with the main body 310. In addition, the coil spring 380 is provided between the holding members 350, 360, 370, 80 and the main body 310, and is always up to the first position where the tip of the center drill 40 protrudes from the tip of the cutting blade 30. The center drill 40 is urged in the direction from the base end side to the tip end side, and the tip of the center drill 40 is moved to the cutting blade according to the external force in the direction from the tip end side to the base end side of the center drill 40. An elastic member is configured to allow the center drill 40 to elastically contract in the axial direction from the tip of 30 to a second position where the center drill 40 is retracted. By the way, the number of the guide shafts 370 is not limited to three, but may be two or four or more as long as the movement of the center drill 40 in the axial direction can be smoothly guided via the support plate 360 and the holder 350. Can be. Moreover, the arrangement | positioning angle interval can also be made into arbitrary angle intervals other than setting it as the same angle interval.

Action and Effect The punching tool according to the fourth embodiment is used in the same manner as the punching tool according to the first embodiment. That is, the center position where the center drill 40 is to be inserted is determined at the position where the wiring box or the like is placed in the wall or the like, the tip of the center drill 40 is brought into contact with the center position, and the rotation axis of the rotation tool is set. The main body 310 is rotated forward through the shaft body 20 by rotating forward. Then, the center drill 40 rotates positively integrally with the main body 310 via the guide shaft 370, the holder 350, and the roll pin 80. At this time, since the cutting blade 30 is also mounted and fixed in the mounting groove 311c of the flange portion 311b, the cutting blade 30 rotates positively integrally with the main body 310. At the same time, when the rotating tool is pressed toward the drilled body such as a wall material and the center drill 40 is pressed toward the drilled body via the main body 310, the center drill 40 is drilled at the center position. The inside of the. Then, when the center drill 40 penetrates the body to be drilled for a predetermined length (projection length), the tip of the roll pin 80 comes into contact with the surface of the body to be drilled. As a result, the center drill 40 does not penetrate further into the drilled body, and the center drill 40 idles relative to the drilled body in the drilled state. At substantially the same time, the cutting blade 30 starts drilling the object to be drilled by the saw blades 33, 34, and 37.

  Here, as described above, the coil spring 380 is provided between the holding members 350, 360, 370, 80 and the main body 310, and the tip of the center drill 40 always protrudes from the tip of the cutting blade 30. The center drill 40 is urged in the direction (first axial direction) from the proximal end side to the distal end side to the position 1 (state shown in FIG. 14). In addition, the coil spring 380 has a first end in which the tip of the center drill 40 is immersed from the tip of the cutting blade 30 in response to an external force in a direction (second axial direction) from the tip side of the center drill 40 toward the base side. To the position of 2, the center drill 40 is allowed to elastically contract in the axial direction.

  Therefore, from the time when the center drill 40 is centered on the drilled body to the time when the center drill 40 penetrates the wall material W and the tip of the roll pin 80 contacts the drilled body, the spring elasticity of the coil spring 380 is used. The upper locking portion 372 of the guide shaft 370 contacts the peripheral edge of the small hole 311d of the disk portion 311a, the support plate 360 and the holder 350 are in the lowest position, and the center drill 40 is in the first position. . Then, when the rotating tool is further pressed toward the drilled body and the cutting blade 30 is further pressed toward the drilled body via the main body 310, the cutting blade 30 is cut while cutting the drilled body. Penetration inside the perforated body. At this time, with the penetration of the cutting blade 30 into the drilled body, the holder 350 approaches the main body 310 via the roll pin 80, and the coil spring 380 contracts against its own elasticity. That is, the cutting blade 30 penetrates into the drilled body in a form that resists the elasticity of the coil spring 380. At this time, as indicated by a two-dot chain line in FIG. 14, the shaft portion 371 of the guide shaft 370 protrudes upward from the small hole 311d of the base portion 311 to guide the movement of the holder 350 and the like in the axial direction. At this time, the center drill 40 moves from the distal end side of the guide hole 22 of the shaft body 20 toward the proximal end side of the center drill 40. When the cutting blade 30 passes through the drilled body, the center drill 40 is in the second position. When the cutting blade 30 penetrates the drilled body and drills a through hole in the drilled body, a coil spring is obtained. Due to the elasticity (biasing force) of 480, the holder 350 moves away from the main body 310, and the center drill 40 returns to the first position. In this way, when the through hole is drilled in the drilled body, the main body 310 is pulled to the front side through the rotating tool, and the cutting blade 30 is separated from the drilled body. Then, the circular excision portion of the drilled body remaining in the cutting blade 30 with the center drill 40 holding the center is pulled out from the center drill 40 and removed. Thereafter, similarly, drilling is performed at an arbitrary position of the drilled body.

  As with the drilling tool according to the first embodiment, the drilling tool according to the fourth embodiment has a simple structure without processing the center shaft part of the center drill 40 or the like, and the center shaft part of the center drill 40 or the like is the main body. It can be made to be non-rotating and telescopic with respect to 310, and as a result, the whole can be produced at low cost. In addition, in the punching tool according to the fourth embodiment, as in the case of the punching tool according to the first embodiment, the main body 310 has a guide hole 22 that extends in the axial direction of the shaft body 20 as a connecting portion, The center drill 40 serving as the center shaft portion is held in a non-rotating state by a holder 350 on the other end side of the holding member and is rotated integrally with the main body 310, while the base end side is a shaft It is inserted into the guide hole 22 of the body 20 so as to be slidable in the axial direction, supported by the guide hole 22 of the front shaft body 20 in a state in which movement in the radial direction is restricted, and centered by the guide hole 22 of the shaft body 20. The expansion / contraction operation between the first position and the second position of the drill 40 is guided. Therefore, the center drill 40 can be guided by the guide hole 22 of the shaft body 20, and the axial movement of the center drill 40 can be smoothed. Further, the center drill 40 rotates integrally with the main body 310 in a state where the tip end side of the center drill 40 is held by the holder 350 on the other end side of the holding member. That is, as compared with the prior art, the center drill 40 rotates integrally with the main body 10 in a state where the distal end side is held. Therefore, the stability at the time of rotation of the center drill 40 increases, and the core blur can be effectively prevented. At the same time, the base end side of the center drill 40 is inserted into the guide hole 22 of the shaft body 20 of the main body 310 so as to be slidable in the axial direction, and movement in the radial direction is restricted by the guide hole 22 of the shaft body 20. Supported by Therefore, the center drill 20 is supported by the shaft body 20 and the holder 350 with respect to the main body 310 at two points, that is, the proximal end side and the distal end side, and the stability at the time of rotation is further increased, and the core Blur can be more effectively prevented. Further, since the center blur can be prevented, when the center drill 40 is expanded and contracted in the axial direction while rotating integrally with the main body 310, the outer peripheral surface of the base end side of the center drill 40 is the guide hole 22 of the shaft body 20. There is no hindrance to the expansion / contraction operation (stroke operation) by being pressed against the inner peripheral surface, and the expansion / contraction operation can be performed smoothly.

  Further, the portion that prevents the center drill 40 from rotating with respect to the main body 310 is a holder 350 on the other end side of the holding member, and the portion that allows the center drill 40 to expand and contract with respect to the main body 310 is the center drill 40. The base end side becomes a guide hole 22 portion of the shaft body 20 into which these are inserted, and these become separate portions. Therefore, as compared with the case where the center drill is prevented from rotating and extending and retracting by the hole portion of the main body as in the prior art, the center direction of the center drill 40 is rotated while integrally rotating with the main body 310. When the center drill 40 is expanded and contracted, there is no great resistance between the center drill 40 and the guide hole 22 portion of the shaft body 20 of the main body 310 in the expansion / contraction direction of the center drill 40, and the center drill 40 expands and contracts (stroke operation). Can be performed very smoothly.

  By the way, in the drilling tool according to Embodiment 4, when the upper locking portion 372 is integrally formed at the upper end of the guide shaft 370 and the center drill 40 is advanced to the first position by the biasing force of the coil spring 380, The upper locking portion 372 is locked in contact with the upper surface of the disk portion 311a, and the center drill 40 is stopped at the first position against the urging force of the coil spring 380. Further, a lower locking portion 373 is integrally formed near the center of the guide shaft 370. When the center drill 40 comes to the second position during drilling, the lower locking portion 373 contacts the lower surface of the disk portion 311a. Locked in contact, the center drill 40 is prevented from further retracting beyond the second position. However, Embodiment 4 can also be implemented without providing the lower locking portion 373 on the guide shaft 370. Also in this case, if the spring length at the maximum contraction of the coil spring 380 is selected so that the center drill 40 comes to the second position when the coil spring 380 is in the maximum contracted state, the center drill 40 is moved to the second position at the time of drilling. , The coil spring 380 is in a maximum contracted state and further contraction is stopped, and the center drill 40 can be prevented from further retracting beyond the second position.

  Furthermore, in the punching device according to the fourth embodiment, the elastic member formed of the coil spring 380 is interposed between the holder 350 of the holding member and the boss 312 of the main body 310, thereby holding the holding member inside the main body. The elastic member may be provided between the holding member and the main body outside the main body. For example, a small tension (shrinkage) coil spring as an elastic member is wound around the shaft portion 371 between the upper locking portion 372 and the upper surface of the disk portion 311a of the base portion 311 of the main body 310, and the upper end is moved to the upper locking portion. The lower end is fixed to the peripheral edge of the small hole 311b on the upper surface of the disk part 311a of the base part 311 of the main body 310, and a tension coil spring is interposed between the upper locking part 372 and the disk part 311a. In this way, a tension coil spring can be provided between the holding member and the main body outside the main body. In this case, at the time of maximum contraction of the tension coil spring, the upper locking portion 372 is pulled downward in FIG. 14 by the tensile force (contraction force), and the center portion 371 of the guide shaft 370 and the support plate 360 are interposed. The center shaft portion composed of the drill 40 comes to the first position. When an external force upward in FIG. 14 is applied to the center drill 40, the tension coil spring expands against the spring force via the support plate 360, the shaft portion 371 of the guide shaft 370, and the upper locking portion 372. Then, the center drill 40 comes to the second position. Similarly to the above, when the center drill 40 comes to the second position, it is preferable that the lower locking portion 373 abuts on the lower surface of the disk portion 311a. In this case, a cylindrical cover that accommodates the upper locking portion 372 and the tension coil spring is integrated with the upper surface side of the disk portion 311a with a length corresponding to the expansion / contraction stroke (stroke) of the upper locking portion 372. It can also be formed.

  Alternatively, even when the elastic member is provided between the main body 310 and the holding member inside the main body 310, in addition to the above, for example, the pressing coil spring is provided with a shaft between the lower surface of the disk portion 311a and the lower locking portion 373. The upper end is fixed to the peripheral edge of the small hole 311b on the lower surface of the disk portion 311a, and the lower end is fixed to the lower locking portion 373 so that the lower end is fixed between the lower surface of the disk portion 311a and the lower locking portion 373. A small pressing coil spring can be interposed. In this case, when the pressing coil spring is fully extended, the lower locking portion 373 is pressed downward in FIG. 14 by the pressing force (extension force), and the shaft portion 371 of the guide shaft 370 and the support plate 360 are used. A center shaft portion including the center drill 40 comes to the first position. When an external force upward in FIG. 14 is applied to the center drill 40, the pressing coil spring contracts against the spring force via the support plate 360, the shaft portion 371 of the guide shaft 370, and the upper locking portion 372. Then, the center drill 40 comes to the second position. Similarly to the above, when the center drill 40 comes to the second position, it is preferable that the lower locking portion 373 abuts on the lower surface of the disk portion 311a. Also in this case, if the spring length at the maximum contraction of the coil spring is selected so that the center drill 40 comes to the second position in the maximum contraction state of the pressing coil spring, the center drill 40 is brought to the second position at the time of drilling. When this happens, the coil spring is in its maximum contracted state and further contraction stops, preventing the center drill 40 from further retracting beyond the second position.

  Furthermore, in the fourth embodiment, the shaft portion 371 of the guide shaft 370 has a cylindrical shape, and the small hole 311b of the disk portion 311a of the main body 310 on which the shaft portion 371 slides is a circular hole corresponding to the shaft portion 371. The shaft portion of the guide shaft 370 may be a prismatic shape, and the small hole 311b of the disk portion 311a of the main body 310 on which the shaft portion 371 slides may be a square hole corresponding to the shaft portion. However, when the shaft portion 371 of the guide shaft 370 is cylindrical, and the small hole 311b of the disk portion 311a of the main body 310 in which the shaft portion 371 slides is a circular hole corresponding to the shaft portion 371, the center drill 40 is made to be the main body 310. When the outer peripheral surface of the shaft portion 371 is slightly pressed against the inner peripheral surface of the small hole 311b of the disk portion 311a when the shaft portion 371 is expanded and contracted in the axial direction while rotating integrally with The peripheral surface is pressed against the corresponding circular peripheral surface of the small hole 311b of the disk portion 311a, the pressing force is evenly distributed in the radial direction, and the shaft portion 371 and the small hole 311b of the disk portion 311a There is no great resistance between the two. As a result, when the center drill 40 is expanded and contracted, the guide shaft 370 does not hinder the expansion and contraction operation, and the center drill 40 can be expanded and contracted extremely smoothly as described above.

Embodiment 5
FIG. 15 is a side view showing a punching device according to Embodiment 5 of the present invention. FIG. 16: is sectional drawing which shows the punching tool which concerns on Embodiment 5 of this invention seeing from the front.
As shown in FIGS. 15 and 16, the drilling tool according to Embodiment 5 includes main bodies 310 and 20, a cutting blade 430, a center drill 40, and holding members 350, 460 and 80. Specifically, the punching tool according to the fifth embodiment includes a main body 310 and a holder 350 similar to the punching tool according to the fourth embodiment. On the other hand, in the fifth embodiment, the cutting blade 430 is mounted and fixed in the mounting groove 311c of the flange portion 311b as in the first embodiment. The cutting blade 430 has substantially the same configuration as the cutting blade 30 of the first embodiment, and has a saw blade 33 and the like, and a pair of guide grooves 439 are formed at positions facing each other in the circumferential direction. Each guide groove 439 has a linear groove shape extending in parallel with the center drill 40 from the lower end of the cutting blade 430 to the vicinity of the upper end.

  On the other hand, in the fifth embodiment, the holding member includes a holder 350, a guide shaft 460, and a roll pin 80. The guide shaft 460 is in the form of a straight bar that protrudes horizontally from the outer surfaces of the holders 350 at right angles. The pair of guide shafts 460 are inserted into the pair of guide grooves 439 of the cutting blade 430 and can move up and down in the guide grooves 439. Each guide shaft 460 is positioned at the first position of the center drill 40, the tip of which is located near the lower end of the guide groove 439 of the cutting blade 430, and at the second position of the center drill 40, the tip thereof is the cutting blade. The guide groove 439 of the 430 is brought into contact with the upper edge and locked. In addition, a pressing (extension) coil spring 480 is interposed between the lower end of the boss portion 312 and the upper end of the holder 350 in a state of being externally mounted on the center drill 40. In the fifth embodiment, the holder 350, the guide shaft 460, and the roll pin 80 are attached to one end side to the cutting blade 430 as a drilling blade in a non-rotating state, and the center drill 40 is prevented from rotating by the other end side. The holding member is configured so that the center drill 40 rotates integrally with the main body 310 while being held in a state. The coil spring 480 is provided between the holding members 350, 460, 80 and the main body 310, and the center drill 40 is always at the first position where the tip of the center drill 40 protrudes from the tip of the cutting blade 430. 40 is urged in the direction from the proximal end side toward the distal end side, and the distal end of the center drill 40 is moved by the cutting blade 430 according to an external force in the direction from the distal end side of the center drill 40 toward the proximal end side. An elastic member is configured to allow the center drill 40 to elastically contract in the axial direction from the tip to the second position where it is immersed. By the way, the number of the guide shafts 370 is not limited to two, and may be one or three or more as long as the movement of the center drill 40 in the axial direction can be smoothly guided through the holder 350. it can. Moreover, the arrangement | positioning angle interval can also be made into arbitrary angle intervals other than setting it as the same angle interval. In this case, the number of guide grooves 439 of the cutting blade 430 is the same as the number of guide shafts 460, and the arrangement angle interval thereof is also the same as the arrangement angle interval of the guide shafts 460.

Action and Effect The punching tool according to the fifth embodiment is used in the same manner as the punching tool according to the first embodiment. That is, the center position where the center drill 40 is to be inserted is determined at the position where the wiring box or the like is placed in the wall or the like, the tip of the center drill 40 is brought into contact with the center position, and the rotation axis of the rotation tool is set. The main body 310 is rotated forward through the shaft body 20 by rotating forward. Then, the center drill 40 rotates positively integrally with the main body 310 via the guide shaft 460, the holder 350, and the roll pin 80. At this time, since the cutting blade 430 is also mounted and fixed in the mounting groove 311c of the flange portion 311b, it rotates positively integrally with the main body 310. At the same time, when the rotating tool is pressed toward the drilled body such as a wall material and the center drill 40 is pressed toward the drilled body via the main body 310, the center drill 40 is drilled at the center position. The inside of the. Then, when the center drill 40 penetrates the body to be drilled for a predetermined length (projection length), the tip of the roll pin 80 comes into contact with the surface of the body to be drilled. As a result, the center drill 40 does not penetrate further into the drilled body, and the center drill 40 idles relative to the drilled body in the drilled state. At substantially the same time, the cutting blade 430 starts drilling the object to be drilled by the saw blades 33, 34, and 37.

  Here, as described above, the coil spring 480 is provided between the holding members 350, 460, 80 and the main body 310, and the first end of the center drill 40 always protrudes from the front end of the cutting blade 30. The center drill 40 is urged in a direction (first axial direction) from the proximal end side to the distal end side until the position (the state of FIG. 17). At this time, the spring length at the maximum extension of the coil spring 480 is selected so that the center drill 40 comes to the first position in the maximum extension state of the coil spring 480. In addition, the coil spring 480 has a first end where the distal end of the center drill 40 is immersed from the distal end of the cutting blade 430 in response to an external force in a direction (second axial direction) from the distal end side to the proximal end side of the center drill 40. To the position of 2, the center drill 40 is allowed to elastically contract in the axial direction.

  Therefore, the coil spring 480 is in the fully extended state from the time when the center drill 40 is centered on the drilled body to the time when the center drill 40 penetrates the wall material W and the tip of the roll pin 80 contacts the drilled body. The holder 450 is located at the lowest position, and the center drill 40 is located at the first position. Next, when the rotating tool is further pressed toward the drilled body and the cutting blade 430 is further pressed toward the drilled body via the main body 310, the cutting blade 430 is cut while drilling the drilled body. Penetration inside the perforated body. At this time, with the penetration of the cutting blade 430 into the drilled body, the holder 350 approaches the main body 310 via the roll pin 80, and the coil spring 480 contracts against its own elasticity. That is, the cutting blade 430 penetrates into the drilled body in a form that resists the elasticity of the coil spring 380. At this time, the tip of the guide shaft 460 moves along the guide groove 439 of the cutting blade 430 to guide the movement of the holder 350 and the like in the axial direction. At this time, the center drill 40 moves from the distal end side of the guide hole 22 of the shaft body 20 toward the proximal end side of the center drill 40. When the cutting blade 430 penetrates the drilled body, the center drill 40 is in the second position, and when the cutting blade 430 penetrates the drilled body and forms a through hole in the drilled body, a coil spring is obtained. Due to the elasticity (biasing force) of 480, the holder 350 moves away from the main body 310, and the center drill 40 returns to the first position. When the through hole is drilled in the drilled body in this manner, the main body 310 is pulled to the front side through the rotating tool, and the cutting blade 430 is separated from the drilled body. Then, the circular excision portion of the drilled body remaining in the cutting blade 430 while the center drill 40 holds the center is pulled out from the center drill 40 and removed. Thereafter, similarly, drilling is performed at an arbitrary position of the drilled body.

  The drilling tool according to the fifth embodiment is the same as the drilling tool according to the first embodiment, and the center shaft portion of the center drill 40 and the like has a simple structure without processing the center shaft portion of the center drill 40 and the like. It can be made to be non-rotating and telescopic with respect to 310, and as a result, the whole can be produced at low cost. In addition, in the drilling tool according to the fifth embodiment, as in the case of the drilling tool according to the first embodiment, the center drill 40 has its distal end side interposed via the guide shaft 460 by the holder 350 on the other end side of the holding member. While being held in a non-rotating state and rotated integrally with the main body 310, the base end side of the shaft body 20 is inserted into the guide hole 22 of the shaft body 20 so as to be slidable in the axial direction. The guide hole 22 supports the movement in the radial direction, and the guide hole 22 of the shaft body 20 guides the expansion and contraction operation of the center drill 40 between the first position and the second position. Therefore, the center drill 40 can be guided by the guide hole 22 of the shaft body 20, and the axial movement of the center drill 40 can be smoothed. In addition, the punching tool according to the fifth embodiment also exhibits the effects described in the fourth embodiment.

  Further, the part that makes the center drill 40 non-rotating with respect to the main body 310 is the holder 350 and the guide shaft 460 on the other end side of the holding member, and the part that makes the center drill 40 telescopic with respect to the main body 310 is The guide hole 22 portion of the shaft body 20 into which the proximal end side of the center drill 40 is inserted becomes a separate portion. Therefore, as compared with the case where the center drill is prevented from rotating and extending and retracting by the hole portion of the main body as in the prior art, the center direction of the center drill 40 is rotated while integrally rotating with the main body 310. When the center drill 40 is expanded and contracted, there is no great resistance between the center drill 40 and the guide hole 22 portion of the shaft body 20 of the main body 310 in the expansion / contraction direction of the center drill 40, and the center drill 40 expands and contracts (stroke operation). Can be performed very smoothly.

  By the way, in the drilling tool according to the fifth embodiment, the center drill 40 is positioned at the first position by selecting the spring length when the coil spring 480 is fully extended. By providing other means for positioning in the axial direction with respect to 430, the center drill 40 may be positioned at the first position and the second position. Specifically, for example, instead of the guide groove 439 whose lower end is opened, a long-hole-shaped guide groove whose upper end and lower end are closed is provided in the cutting blade 430, and the guide shaft 460 is vertically moved along the guide groove. Try to move. If it carries out like this, a guide shaft will contact | abut and latch to the lower end periphery of the guide groove of the cutting blade 430, and the said center drill 40 can be positioned in a 1st position.

  By the way, in each said embodiment, although the saw blade-shaped cutting blades 30 and 430 are used as a drilling blade, in this invention, a single cutting blade-shaped drilling blade can also be used besides this. it can. In this case, one or more cutting blades are fixed so as to hang down from the outer peripheral edge of the main body such as a flange. Moreover, in each said embodiment, although the center drill 40 is used as a center axis | shaft part, in this invention, center axis parts of other structures, such as a center pin and a center axis | shaft, can be used besides this. it can.

FIG. 1 is an exploded perspective view showing a punching device according to Embodiment 1 of the present invention. FIG. 2 is a perspective view showing the punching tool according to Embodiment 1 of the present invention. FIG. 3 is a front view showing the left half part of the punching tool according to Embodiment 1 of the present invention in a cross-section and a part of the right half part broken away. FIG. 4 is a plan view showing the drilling tool according to Embodiment 1 of the present invention. FIG. 5 is a developed view showing a developed state of the drilling blade of the drilling tool according to Embodiment 1 of the present invention. FIG. 6 is an exploded perspective view showing the relationship between the holding member of the punch and the center drill according to Embodiment 1 of the present invention. FIG. 7 is a front view showing a state in which a roll pin is attached to the center drill of the drilling tool according to Embodiment 1 of the present invention. FIG. 8 is a perspective view showing a state in which a roll pin is attached to the center drill of the drilling tool according to Embodiment 1 of the present invention. FIG. 9 shows a drilling operation of the drilled body by the drilling tool according to Embodiment 1 of the present invention, (a) is a cross-sectional view showing the center drill positioned at the drilled body, and (b) is a drilling blade. It is sectional drawing which shows the state which perforated the to-be-pierced body by. FIG. 10 is a cross-sectional view showing the punch according to the second embodiment of the present invention as viewed from the right side. FIG. 11 shows a drilling operation of the drilled body by the drilling tool according to the third embodiment of the present invention, (a) is a cross-sectional view showing the center drill positioned at the drilled body, and (b) is a drilling blade. It is sectional drawing which shows the state which perforated the to-be-pierced body by. FIG. 12 is a cross-sectional view showing processing when the plate-like member of the holding member of the punching tool according to Embodiment 3 of the present invention is elastically deteriorated. FIG. 13 is a plan view showing a punching tool according to Embodiment 4 of the present invention. 14 is a cross-sectional view taken along line AA in FIG. FIG. 15 is a side view showing a punching device according to Embodiment 5 of the present invention. FIG. 16: is sectional drawing which shows the punching tool which concerns on Embodiment 5 of this invention seeing from the front.

Explanation of symbols

10,310 Main body, 11,311 Base 20 Shaft (connecting portion), 22 Guide hole 30,430 Cutting blade (drilling blade)
40 Center drill (center shaft)
50,250 Leaf spring (holding member, plate-like member) 51,251 Bent part 60 Upper holder (holding member), 70 Lower holder (holding member)
78 regulation piece,
80,480 Roll pin (holding member, contact part)
101 Adjustment screw 350 Holder (holding member), 360 Support plate (holding member), 370 Guide shaft (holding member)
380 Coil spring (elastic member)
460 Guide shaft (holding member), 480 Coil spring (elastic member)
W Wall material (to be drilled)

Claims (14)

A main body having a connecting portion connectable to a rotating shaft of a driving portion of the rotating tool;
A drilling blade extending from the main body and rotating integrally with the main body to drill a through-hole in the drilled body;
A center shaft portion serving as a rotation center of the drilling blade;
One end side is attached to the main body in a non-rotating state, and the other end side holds the center shaft portion in a non-rotating state so that the center shaft portion rotates together with the main body. With members,
The holding member is always elastic to urge the center shaft portion in the direction from the proximal end side to the distal end side to a first position where the distal end of the center shaft portion protrudes from the distal end of the drilling blade. And the center shaft to a second position where the tip of the center shaft portion is recessed from the tip of the drilling blade in response to an external force in a direction from the distal end side to the proximal end side of the center shaft portion. A punching device which allows the part to elastically retract in the axial direction. The holding member has a plate-like member extending between the one end side and the other end side, and attaches one end side of the plate-like member to the main body in a non-rotating state. Holding the center shaft portion in a non-rotating state by the other end side,
The plate-like member can be bent or bent between one end side and the other end side of the holding member so that the center shaft portion can expand and contract between the first position and the second position. The punch according to claim 1, wherein:   The plate-like member always has its own elasticity to expand to the maximum length between one end side and the other end side of the holding member, and the center shaft portion is the first shaft in the extended state. And the center shaft portion is elastically bent or curved from the extended state in response to contraction of the center shaft portion from the first position to the second position. 2. The punch according to 2. The main body has a substantially plate-like base portion that disposes the drilling blade on the outer periphery, and the connecting portion has a shaft body that is integrally fixed to one side in the thickness direction of the base portion,
4. The plate-like member, wherein the one end side is fixed to the shaft body, penetrates the base portion in the thickness direction, and the center shaft portion is fixed to the other end side. Drilling tool.   The protruding length of the center shaft portion held by the holding portion from the holding portion is set to be less than the thickness of the drilled body so that the center shaft portion does not penetrate the drilled body. The punch according to any one of claims 1 to 4.   6. The punching tool according to claim 5, wherein a protruding length of the center shaft portion held by the holding portion from the holding portion can be changed according to a thickness of the drilled body.   The holding member further includes a contact portion that holds the center shaft portion in a state in which a tip portion of the center shaft portion protrudes for a predetermined length, and the center shaft portion is drilled into the drilled body for the predetermined length. When this is done, the tip of the abutting part comes into contact with the surface of the body to be drilled to prevent further penetration of the center shaft part, and against the elasticity of the holding member, the center shaft part The piercing tool according to any one of claims 1 to 6, wherein the piercing tool is retracted toward the second position.   Further, an adjustment screw that is screwed into the base portion of the main body and penetrates the base portion and extends toward the other end side of the holding member, and is provided on the other end side of the holding member and faces the tip end of the adjustment screw When the center shaft portion is in the second position, the tip of the adjustment screw comes into contact with the restriction piece, and the center shaft portion is further moved from the second position. The punching device according to claim 4, wherein the punching device is prevented from moving backward.   When the center shaft portion is in the second position, the bent or curved portion of the plate-like member comes into contact with the outer peripheral portion of the base of the main body, and the plate-like member prevents further bending or bending. 5. The punching device according to claim 4, wherein the center shaft portion is prevented from further retracting from the second position. A main body having a connecting portion connectable to a rotating shaft of a driving portion of the rotating tool;
A drilling blade extending from the main body and rotating integrally with the main body to drill a through-hole in the drilled body;
A center shaft portion serving as a rotation center of the drilling blade;
One end side is attached to the main body in a non-rotating state, and the other end side holds the center shaft portion in a non-rotating state so that the center shaft portion rotates together with the main body. A member,
The center shaft portion is provided between the holding member and the main body, and the center shaft portion is always moved from the proximal end side to the distal end side to a first position where the tip end of the center shaft portion protrudes from the tip end of the drilling blade. And a second position where the tip of the center shaft portion is recessed from the tip of the drilling blade in response to an external force in a direction from the tip side of the center shaft portion toward the base end side. A punching device comprising: an elastic member that allows the center shaft portion to elastically retreat in the axial direction. A main body having a connecting portion connectable to a rotating shaft of a driving portion of the rotating tool;
A drilling blade extending from the main body and rotating integrally with the main body to drill a through-hole in the drilled body;
A center shaft portion serving as a rotation center of the drilling blade;
One end side is attached to the drilling blade in a non-rotating state, and the other end side holds the center shaft portion in a non-rotating state so that the center shaft portion rotates together with the main body, And the holding member attached to the drilling blade at the one end side so that the center shaft portion held by the other end side is movable along the extending direction of the drilling blade;
The center shaft portion is provided between the holding member and the main body, and the center shaft portion is always moved from the proximal end side to the distal end side to a first position where the tip end of the center shaft portion protrudes from the tip end of the drilling blade. And a second position where the tip of the center shaft portion is recessed from the tip of the drilling blade in response to an external force in a direction from the tip side of the center shaft portion toward the base end side. A punching device comprising: an elastic member that allows the center shaft portion to elastically retreat in the axial direction. The main body has a guide hole extending in the axial direction of the connecting portion;
The center shaft portion is held in a non-rotating state by the other end side of the holding member so that the center shaft portion is rotated together with the main body, and the base end side is a guide hole of the connecting portion. It is inserted so as to be slidable in the axial direction and supported in a state in which movement in the radial direction is restricted by the guide hole of the connecting portion,
The punching tool according to any one of claims 1 to 11, wherein an extension / contraction operation between the first position and the second position of the center shaft portion is guided by the guide hole of the connecting portion.   The punching tool according to claim 12, wherein the guide hole is provided so as to penetrate the connecting portion in the axial direction. )
The drilling tool according to any one of claims 1 to 13, wherein the drilling blade has a saw blade shape continuous in a circumferential direction of the main body.

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