JP4463647B2 - Drilling tool - Google Patents

Description

  The present invention relates to a drilling tool that is attached to a rotary tool such as an electric drill as an attachment and rotates a rotary shaft by the power of the rotary tool to drill through holes of various diameters in a ceiling plate, a wall plate, etc. is there.

  As one of the above-described punching tools, the one disclosed in Patent Document 1 is known. In the drilling tool disclosed in Patent Document 1, the hole diameter is adjusted by loosening the set screw 17 and sliding the arm 16 by hand along the long hole 20 to change the distance from the center drill 14 to the blade 18. . However, in the above operation, the pair of arms 16 are manually slid, the scale provided on the arms 16 is adjusted to a predetermined diameter, and the set screw 17 is loosened and fixed. Misalignment of the fixed positions of both arms 16 with respect to the body 15 is likely to occur. There are also misreading of scales. In this case, there is a problem that the distance from the center drill 14 to each blade 18 is shifted, and a through hole having a predetermined diameter cannot be drilled neatly. Further, since both arms 16 can be rotated around the center drill 14, the arms 16 are rotated in operations such as loosening and tightening the set screw 17 and sliding operations of the arms 16. The adjustment of the hole diameter is difficult to perform, and the blade 18 may turn unexpectedly, resulting in injury.

  In view of this, there is one disclosed in Patent Document 2 as a drilling tool that prevents the above-described problems by displacing each blade with respect to the center drill by interlocking a pair of arms. In the one shown in FIG. 1 of Patent Document 2, the base is screwed onto a feed screw shaft having a thread portion in the reverse direction, and the interval between the blades attached to each base is adjusted by the rotation of the feed screw shaft. To do. In this configuration, since the feed screw shaft exists regardless of the drilling diameter, for example, when trying to drill a small-diameter through hole in the ceiling near the wall, the feed screw shaft interferes with the wall. Drilling may not be possible. In FIG. 1 of Patent Document 2, the pair of blades are covered with a cover, and there is a problem that the cover itself interferes with the wall. However, the above problem is a case where it is assumed that the cover is removed.

In addition, the punching tool disclosed in FIG. 6 of Patent Document 2 has a configuration in which a pair of blades are interlocked by a wire 31, and the screw body 33 is rotated so that the wire 31 is not loosened. . However, the wire is prone to loosening, and when loosening occurs, the arm is rattled, and the loose state of the pair of wires is not uniform, which is very dangerous.
JP-A-5-318213 Japanese Patent Laid-Open No. 5-28602

  The present invention secures the distance from the center drill to each blade body without rotating the blade body inadvertently during the operation of changing the distance between the pair of blade bodies, and easily and reliably sets the distance between the pair of blade bodies. The challenge is to provide a drilling tool that can be changed.

The invention according to claim 1 for solving the above-described problem is characterized in that a center shaft fixed to the arm body mounting holder, and extending in a direction orthogonal to the axial direction of the center shaft, A pair of arm bodies attached opposite to each other so as to be slidable in the extending direction, a pair of blade bodies attached to each arm body, and the arm body attached concentrically with the center shaft And a drive shaft support holder that rotatably supports a drive shaft that is integrally attached to the holder , wherein the pair of concave and convex rack teeth can face each other in an oblique vertical direction. A pair of rack bodies respectively formed in the extending direction of the arm body, and a pinion shaft mounted on the arm body mounting holder perpendicular to the center axis, and the pinion Comprises a structure of the pinion unit whose phases are respectively meshed with the racks body in 180 ° different parts, and the drive shaft supporting holder mounted a cover member to cover the pair of the blade, due to the rotation of the pinion It is characterized in that the perforation diameter can be adjusted by changing the distance between the pair of blades attached to each arm body by sliding the pair of arm bodies in the reverse direction.

According to the first aspect of the present invention, the pin attachment shaft is supported by the arm body attachment holder so as to be orthogonal to the center shaft. For this reason, when a pair of arm bodies are synchronously slid in the opposite direction by the same amount by the rotation of a pinion provided on the pinion shaft, and the distance between the pair of blade bodies is changed, the center shaft is rotated. Little force is generated. For this reason, there is no fear that the pair of arm bodies, that is, the pair of blade bodies rotate, during the interval changing operation of the pair of blade bodies, and the change operation can be performed safely. In addition, the pinion shaft is orthogonal to the protruding direction of each blade body (direction parallel to the center axis), and is disposed at a substantially central portion of each blade body. The distance between the pair of blades can be changed in a state where there is no possibility of contact with the blade, so that this is also safe. Further, the pinion provided on the pinion shaft is meshed with the rack teeth of each rack body attached to the pair of arm bodies at portions where the phases are different by 180 °. Each blade attached to the outer end always moves while maintaining the same distance from the center axis (each blade is always located on the same circumference centered on the center axis).

  The invention of claim 2 is characterized in that, in the invention of claim 1, the pair of arm bodies are configured to be fixed to the arm body attaching holder via one tightening bolt. The pair of arm bodies can be fixed to the arm body attaching holder by the tightening bolts of the book. Therefore, when the fixing operation is performed after the distance between the pair of blade bodies corresponding to the hole diameter of the perforated hole (through hole) is changed, the fixing operation of the pair of arm bodies with respect to the arm body attaching holder is facilitated.

The invention of claim 3 is the invention of claim 1 or 2, wherein the drive shaft supporting the holder, since the cover member is detachably attached, for example, when drilling a small diameter hole in the wall Is performed by increasing the overlapping length of each arm body in a side view and reducing the distance between the pair of blade bodies. For this reason, when drilling the small-diameter through hole, the small-diameter through hole can be drilled in the ceiling wall near the wall by removing the cover body that may interfere with the wall. In addition, the configuration in which the overlapping length of the pair of arm bodies is long in a side view also increases the possibility of drilling a small-diameter through hole near the wall.

  According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, the chips generated by the drilling of the pair of blade bodies are prevented from clogging in the recesses between the rack teeth. A chip discharge path provided in communication with the recess toward the opposite side of the rack teeth in the recess to pass and discharge the chips that have entered the recess, and in the chip discharge path A chip discharge port provided in communication with the chip discharge path on the side of the rack body or on the side facing the rack teeth. It is a feature.

  A large amount of chips are generated during drilling work by rotating a pair of blades around the center axis, and they try to deposit on the uneven rack teeth of the rack body that constitutes the rack and pinion mechanism. To do. In the invention of claim 4, since the above-described chip discharge path and chip discharge port are formed in the rack body, the chips to be deposited on the surface of the uneven rack teeth are adjacent to each other. After passing through the chip discharge path formed toward the opposite side of the rack teeth so as to communicate with the recesses between the rack teeth, the rack body from the chip discharge port communicating with the chip discharge path Discharged to the outside. Moreover, during the drilling operation, vibration is generated in the entire drilling tool, and this vibration acts so that the chips are easily discharged from the chip discharge path. As a result, chips are not deposited on the uneven rack teeth on the surface of the rack body, and the pair of arm bodies are synchronously slid in the opposite directions by the rack and pinion mechanism, and the distance between the pair of blade bodies is increased. The work of changing to the hole diameter can be performed reliably.

  A pinion shaft is supported at right angles to the center axis on the arm attachment holder constituting the punching tool according to the present invention. For this reason, when rotating the pinion provided on the pinion shaft, the pair of arm bodies are synchronously slid in the opposite directions by the same amount to change the distance between the pair of blade bodies, thereby attempting to rotate the center shaft. Since almost no rotational force is generated, the changing operation can be performed safely. In addition, the pinion shaft is disposed perpendicular to the protruding direction of each blade body (direction parallel to the center axis), and is disposed at the substantially central portion of each blade body, so that it contacts each blade body. Since the work for changing the distance between the pair of blades can be performed in a state where there is no fear, this is also safe.

Hereinafter, the present invention will be described in more detail with reference to the best mode of the present invention. 1 is a perspective view in which a part of a punching tool C according to the present invention is broken, FIG. 2 is a plan view, FIG. 3 is a front sectional view, and FIG. it is an exploded perspective view of a main part of a (portion excluding the drive shaft supporting the holder H ₁ and cover V). 1 to 4, the drilling tool C supports the drive shaft 10 while being urged in the backward direction by the restoring force of the compression spring 1 and the center shaft S in which the drill portion 24 is formed only at the tip portion. A substantially cylindrical drive shaft support holder H _1, and a block-shaped arm body attachment holder H ₂ that is integrally attached to a portion of the drive shaft 10 that protrudes from the drive shaft support holder H ₁ to the perforation side; A pair of arm bodies A that are slidably mounted along the direction perpendicular to the protruding direction of the center shaft S on the outside of the opposite side surface of the arm body mounting holder H ₂ , and the pair of arm bodies A are synchronized. And a rack and pinion mechanism R (see FIG. 6) for sliding the same amount in opposite directions to each other, and an opposing end portion (opposite end portion) along the longitudinal direction of the pair of arm bodies A. A pair of blades K Eteiru.

In FIG. 3, the drive shaft support holder H ₁ is rotated to the outside of the holder main body 3 having the cover attaching saddle plate portion 2 formed at one end thereof, and the portion of the holder main body 3 opposite to the saddle plate portion 2. In order to prevent the cutting depth adjusting ring 4 that is movably fitted and the cutting depth adjusting ring 4 from coming out of the holder main body 3, there are a plurality of end surfaces on the opposite side of the holder 2 from the plate 2. And a lid 5 attached via screws (not shown). The drive shaft 10 is pierced and supported by the holder body 3 while being urged in the backward direction by the restoring force of the compression spring 1. The compression spring 1 is housed in a cylindrical portion 3 a of the holder body 3 and is elastically mounted between a bottom surface 3 b of the cylindrical portion 3 a and a spring support 6 attached integrally to the drive shaft 10. The spring support 6 is integrally provided with a contact arm 6a along the radial direction thereof, and advances and retreats together with the drive shaft 10, but does not rotate when the drive shaft 10 rotates. In the portion of the cutting depth adjusting ring 4 whose central angle is in the range of about 180 °, a contact surface 4a with which a contact arm 6a provided integrally with the spring support 6 contacts is formed. The distance between the contact surface 4a and the outer end surface 4b of the cutting depth adjusting ring 4, in other words, the movement distance of the contact arm 6a of the spring support 6 gradually changes along the circumferential direction. With this structure, by rotating the cutting depth adjusting ring 4 with respect to the holder body 3, the protruding length of the drive shaft 10 with respect to the return position of the compression spring 1, that is, the cutting depth of the pair of blades K is obtained. Is adjustable. The cylindrical portion 3 a of the holder body 3 is formed with a slit 3 c into which the abutment arm 6 a provided integrally with the spring holder 6 is inserted along the axial direction of the drive shaft 10.

In FIG. 4, a block-shaped arm attachment holder H ₂ is integrally attached to the tip of the portion of the drive shaft 10 protruding from the drive shaft support holder H ₁ . In addition, the base end portion of the center shaft S is inserted and attached to the arm body attaching holder H _{2 so as} to be concentric with the drive shaft 10. Center axis S, in the case of breakage or the like is attached to the arm member attaching the holder H ₂ replaced. A pair of arm bodies A are attached to the outside of the opposite side surfaces of the arm body attaching holder H ₂ through the rack and pinion mechanism R so as to be slidable by the same amount in the opposite directions. The pair of arm bodies A have the same configuration except that the mounting positions along the vertical direction of the rack body 12 mounted on the inner surface of the arm body main body 11 are different, and the arm body A having the same configuration is shared. Yes. That is, the rack body 12 is attached to one arm body A at one end in the width direction (the upper end when the ceiling plate P is perforated), and the other arm body A has a width. A rack body 12 is attached to the other end portion in the direction. Therefore, in a state where the rack body 12 is attached to each of the pair of arm bodies A, the respective rack teeth 12a are opposed to each other along the oblique direction (in the posture in which the ceiling plate P is drilled, the oblique vertical direction). . The arm body main body 11 is extended along a direction orthogonal to the center axis S in a state of being attached to the arm body attachment holder H ₂ , and the arm body main body 11 has arm arms at both ends in the width direction. preparative flange-shaped guided portion 11a which is fitted with a predetermined gap to each guide portion 25b formed on the upper and lower ends of the arm body attachment surface 25 which is opposite side of the body attachment holder H ₂ is It is bent inward based on the wearing state. One end portion in the longitudinal direction of the arm body main body 11 is bent inward at a substantially right angle with respect to the attachment state to form a blade body attachment portion 11b, and an outer surface of the blade body attachment portion 11b. The blade body K is attached to the top via bolts 13, washers 14 and washers 17 facing upward. A long hole 11c for inserting a pinion shaft 26 and a fastening bolt 41, which will be described later, is formed along the longitudinal direction in the center portion of the arm body main body 11 in the width direction. A rack 15 disposed below the elongated hole 11c is fixed to the inner side surface of one arm body main body 11 of the pair of arm bodies A via screws 16 with the rack teeth 12a facing upward. At the same time, a rack 15 disposed above the elongated hole 11c is fixed to the inner side surface of the other arm body main body 11 with screws 16 with the rack teeth 12a facing downward. Therefore, each rack 15 fixed to the inner surface of each arm body main body 11 constituting the pair of arm bodies A has the same number of teeth meshing with these, and the pitch circle diameter of each pinion 27 having the same pitch circle diameter. They are displaced along the vertical direction by the amount. As a matter of course, the pitch of each rack body 12 attached to the pair of arm bodies A is equal to the pitch of each pinion 27. As a result, in a state where the attached so as to face the pair of arm members A to each arm body attachment surface 25 of the arm member attached holder H ₂ slidably, each mounted on the inner surfaces of the pair of arm members A The rack teeth 12a of the rack body 12 are opposed to each other along the oblique vertical direction. In FIGS. 4 and 5, reference numeral 18 denotes an insertion hole for the screw 16 formed on both ends of the arm body body 11 in the longitudinal direction.

FIG. 5 is a perspective view showing a state in which a pair of arm bodies A are slidably attached to the arm body attaching holder H ₂ by the same amount in opposite directions via the rack and pinion mechanism R and the fastening bolt 41. 6 is an exploded perspective view of the rack and pinion mechanism R, FIG. 7 is a sectional view taken along line XX of FIG. 3, and FIG. 8 is a sectional view taken along line YY of FIG. is there. 4 to 8, the arm body attaching holder H ₂ is provided with a pinion shaft through hole 22 and a tightening bolt through hole 23 extending in a direction perpendicular to the center shaft through hole 21. That is, the center shaft through hole 21 is provided in a plane parallel to the end surface of the drive shaft support holder H _{1 in} the arm body attaching holder H ₂ , and the pinion shaft through hole 22 and the tightening bolt through hole 23 are formed in the arm body. The arm holder A in the attachment holder H ₂ is penetrated on the surface to be attached. As shown in FIG. 7, the pinion shaft through hole 22 and the fastening bolt through hole 23 are provided on both sides of the center shaft through hole 21 at equal intervals with the through hole 21. The center shaft S has a smaller diameter than the drive shaft 10, and the center shaft S is fixed to the arm body mounting holder H ₂ by a non-rotating screw (not shown), and the driving shaft 10 is fixed to the arm body mounting holder H 2. It is fixed to ₂ by welding.

In each arm member attachment surface 25 of the arm member attached holder H _2, a pinion accommodating recess 25a is formed to face (see FIGS. 4 and 7). As shown in FIGS. 6 to 8, pinions 27 arranged in the pinion receiving recesses 25 a are fixed to the pinion shafts 26 penetrating the pinion shaft through holes 22 at a predetermined interval, so that the pinion A unit PU is formed. The arm bodies A are respectively arranged outside the pinions 27 of the pinion unit PU, and the respective pinions 27 and the rack teeth 12a of the rack bodies 12 of the pair of arm bodies A mesh with each other. That is, as shown in FIG. 6, the pair of pinions 27 constituting the pinion unit PU is fixed to the pinion shaft 26 at a predetermined interval, and one pinion 27 is one of the pinions 27 disposed above it. While meshing with the rack teeth 12a of the rack body 12, the other pinion 27 meshes with the rack teeth 12a of the other rack body 12 arranged below the other. With this configuration, the rotation of the pinion shaft 26 disposed in the direction orthogonal to the center axis S at a position close to the center axis S reverses the pair of arm bodies A to which the rack body 12 is integrally attached to the inner surface. The same amount can be slid synchronously in the direction. Both end portions of the pinion shaft 26 constituting the pinion unit PU project through the long holes 11c of the arm body main body 11 constituting the pair of arm bodies A, and each arm body A is one end portion of the pinion shaft 26. The pin 28 is sandwiched between the end face 28a of the knob 28 and the stop ring 29 attached to the other end of the pinion shaft 26 with a predetermined gap. Therefore, without the outside pair of arm members A relative to the arm member mounted holder H _2, which is slidable by the same amount in opposite directions. 4, 7, and 8, reference numeral 31 denotes an E-ring that prevents the retaining ring 29 fitted on one end of the pinion shaft 26 from being removed.

As described above, by rotating the pinion shaft 26, the pair of arm bodies A are slid by the same amount in opposite directions, and the distance between the pair of blade bodies K attached to the opposite end portions of the arm bodies A ( After changing D) to be the same as the bore diameter, the pair of arm bodies A are fixed to the arm body attaching holder H ₂ via the fastening bolts 41. 2 and 7, a solid line and a two-dot chain line indicate the maximum interval (D ₁ ) and the minimum interval (D ₂ ) of the pair of blades K, respectively. Fastening bolt 41 is in a state of arranging the arm member A to the respective arm member attachment surface 25 of the arm member attached holder H _2, the arm member attached holder H with the _second fastening bolt through-holes 23 and the arm members It penetrates the A long hole 11c. The arm body attaching holder H ₂ and the pair of arm bodies A attached to face each arm body attaching surface 25 of the holder H ₂ include a head 41 a at one end of the fastening bolt 41, It is firmly sandwiched and integrated by the end face of the nut 42 with the knob screwed to the other end of the fastening bolt 41. In this state, the center shaft S rotates, and the pair of arm bodies A attached to the center shaft S via the arm body attaching holder H ₂ rotate about the center shaft S, thereby a pair of A pair of blades K attached to opposite ends of the arm body A rotate, and through holes B having the same inner diameter as the distance (D) between the pair of blades K with respect to the wall plate such as the ceiling plate P or the like. Is perforated. 4 and 7, reference numeral 43 denotes a washer interposed between the outer surface of one arm body A and the end surface of the nut 42 with knob.

Further, as shown in FIG. 5, a pair of blades K is included in the guided portion 11 a on the side where the drill portion 24 of the center shaft S is disposed, among the pair of guided portions 11 a constituting each arm body A. A scale 32 for displaying the same drilling diameter as the interval (D) is provided. The arm member mounted holder H ₂ guided portion 11a and the surface 34 of the same side of the scale 32 of the pair of surfaces has been subjected to the center shaft S is opposed penetrates in the reference position for reading the graduations 32 An arrow 33 is formed.

  Here, when the pair of arm bodies A are slid using the rack and pinion mechanism R, chips generated during drilling are clogged in the recesses 12b between the rack teeth 12a of the rack body 12, and the rack Operation of the pinion mechanism R may be difficult or impossible. In particular, when the material of the wall board is gypsum board or the like, the amount of chips generated is large, and therefore the chips are easily clogged in the recesses 12b between the rack teeth 12a. Therefore, as shown in FIGS. 6 and 9, the rack body 12 has a structure capable of preventing clogging of the chips L generated at the time of drilling into the recesses 12 b between the adjacent rack teeth 12 a. That is, the bottom surface of the recess 12b between the adjacent rack teeth 12a is an inclined surface that is largely inclined with respect to the tooth thickness direction Q of the rack teeth 12a to constitute the chip discharge passage 12c. The formation end of the powder discharge path 12c is greatly opened to the side to form a chip discharge port 12d. Therefore, in the rack body 12 in which the rack teeth 12a face upward when the ceiling plate is drilled, the chips L generated during the cutting and falling onto the rack teeth 12a are discharged from the chips formed by the inclined surfaces. Since it falls smoothly along the path 12c and is discharged from the side chip discharge port 12d, the chips L are less likely to clog the recesses 12b between the adjacent rack teeth 12a. Further, by forming the chip discharge passage 12c between the adjacent rack teeth 12a, the space volume of the adjacent rack teeth 12a is increased. Can be one of the reasons why it doesn't get stuck. On the other hand, even in the rack body 12 in which the rack teeth 12a face downward when the ceiling plate is drilled, chips are less likely to be clogged between the rack teeth 12a due to the attitude of the rack body 12 when drilling. There is a case of a wall plate without being limited to a plate, and there are various cases in which the drilling tool is installed after drilling. Therefore, in the chip discharge path 12c formed between the adjacent rack teeth 12a, the chips are clogged in the recesses 12b between the rack teeth 12a even when the rack teeth 12a face upward. It can fulfill the function of preventing

  Further, in the rack body 12 shown in FIG. 10, the central portion along the tooth thickness direction Q of the rack teeth 12 a is the highest on the bottom surface of the recess 12 b between the adjacent rack teeth 12 a, and the tooth thickness A pair of chevron-shaped chip discharge passages 12 c are formed such that both ends in the direction are lowered, and the chip discharge passages 12 c are formed on both side surfaces of the rack body 12. Also with this configuration, the chips L that enter the recesses 12b between the adjacent rack teeth 12a and are to be deposited in the recesses 12b pass through the chevron-shaped chip discharge ports 12d and pass through the chip discharge ports on both sides. It is smoothly discharged from 12d to the outside of the rack body 12.

  Further, the rack body 12 shown in FIG. 11 is obtained by deepening the recesses 12b between the adjacent rack teeth 12a, and the chips L temporarily accumulated in the deep recesses 12b act on the rack body 12. Is discharged from the chip discharge ports 12d on both side surfaces of the rack body 12 by the vibration. For this reason, the chips L are not clogged between the recesses 12b between the adjacent rack teeth 12a.

  The rack body 12 ′ shown in FIG. 12 is spaced from the side surface of the arm body A in the tooth thickness direction Q perpendicular to the extending direction M at a predetermined interval along the extending direction M of the arm body A. A large number of independently projecting protrusions N are formed, rack teeth 12a ′ are formed by the protrusions N, and recesses 12b ′ are formed between adjacent protrusions N, and the rack body A chip discharge port 12d ′ is formed at a total of three locations including the lower surface and both side surfaces of 12 ′. The rack body 12 'has an advantage of high chip discharge capability because large chip discharge ports 12d' are formed in three different directions.

  In each rack body 12 shown in FIGS. 10 to 12, chip discharge ports 12 d are formed on both sides of the rack body 12, but the chip discharge ports 12 d of the rack body 12 in the arm body main body 11 are formed. For example, if a discharge hole is formed in the part, the chips can be discharged to the side of the arm body main body 11 through the discharge hole.

Further, the drive shaft supporting the holder H _1, a cover V that chips are prevented from scattering to the periphery is mounted detachably at the perforation. Figure 13 is a cover removed V from the drive shaft supporting the holder H ₁ is a partially broken perspective view from obliquely below, FIG. 14 (a) saw the bottom wall 52 of the cover V from the outside FIG. 15B is an enlarged cross-sectional view taken along the line Z ₁ -Z _{1 of} FIG. 15B. FIG. 15B shows the cover mounting saddle plate portion 2 of the drive shaft support holder H ₁ as a center. a view from the proximal end side of the shaft S, the (b) is a Z ₂ -Z ₂ line enlarged cross-sectional view of the same (b). As shown in FIGS. 1 and 13, the cover V includes a peripheral wall 51 which is cylindrical, the holder main body 3 of the drive shaft supporting the holder H ₁ can be inserted a through hole 52a is formed at the center bottom wall consists parts 52, the bottom wall portion 52 is detachably attached to the wearer flange plate 2 preparative cover of the drive shaft supporting the holder H _1. On the opening side of the peripheral wall 51, a flange-shaped flange 51a is formed integrally with the outside, and the flange 51a is a vibration for contacting the wall plate and absorbing vibrations or the like when drilling. The absorber 53 is affixed. The vibration absorber 53 is made of an elastic body such as rubber.

As shown in FIGS. 13 and 14, an annular protrusion 54 is formed at a portion facing the insertion hole 52 a outside the bottom wall portion 52 of the cover V, and an inner peripheral surface 54 a of the annular protrusion 54. A plurality of (three in the embodiment) arcuate fitting protrusions 55 are formed in the state of entering the insertion hole 52a at equal intervals along the circumferential direction. When the thickness (T ₁ ) on the inner peripheral surface 54 a side including the annular protrusion 54 is set, the thickness (T ₂ ) of the fitting protrusion 55 is equal to the thickness (T ₁ ). The fitting protrusion 55 is substantially half and formed integrally with the inner peripheral surface 54a of the annular protrusion 54 so as to be most biased to the inside of the cover V. A contact portion 56 is formed on the outer surface of one end portion along the circumferential direction of each fitting protrusion 55 by abutting one end surface in the circumferential direction of a sandwiching protrusion 61 described later. Further, as shown in FIG. 14 (b), in order to removably cover V with respect to the drive shaft supporting the holder H _1, arc-shaped space between the fitting projection 55 adjacent phases It is formed, the space portion has the insertion arrangement portion 57 for the the clamping projections 61 to be described later of the drive shaft supporting the holder H ₁ insertable arrangement. Further, as shown in FIGS. 3 and 14 (a), the cover mounting saddle plate portion 2 is fitted on the inner surface side of the portion facing the insertion hole 52a of the bottom wall portion 52 of the cover V. A fitting recess 58 is formed. In FIG. 14A, reference numeral 59 denotes a portion facing the insertion hole 52a of the bottom wall portion 52 of the cover V, and is formed at a position corresponding to the central portion in the circumferential direction of the specific fitting projection 55. A screw insertion hole is shown.

On the other hand, as shown in FIG. 15, the fitting protrusion formed on the cover V is formed on the outer peripheral surface of the holder main body 3 of the drive shaft support holder H ₁ in the vicinity of the cover mounting saddle plate portion 2. An arcuate pinching protrusion 61 corresponding to the fitting protrusion 55 is integrally formed with an interval corresponding to a thickness (T ₂ ) of 55. A space formed by the cover attaching saddle plate 2 and the sandwiching protrusion 61 is an accommodation space 62 for accommodating the fitting protrusion 55 of the cover V. Further, as shown in FIG. 15 (b), in order to removably cover V with respect to the drive shaft supporting the holder H _1, a space portion in which the arcuate between clamping projections 61 adjacent phases The space portion is formed as an insertion arrangement portion 63 for allowing the fitting protrusion 55 of the cover V to be inserted and arranged. Incidentally, FIG. 15 in (b), 64, is screwed to inserted into the screw insertion hole 59 of the cover V bis, drive shaft supporting the holder H ₁ of the cover preparative worn bottom wall of the cover V collar plate portion 2 In order to fix the part 52, the screw pilot holes formed in the position corresponding to the center part of the circumferential direction of each clamping protrusion 61 in the cover mounting saddle part 2 are shown.

Figure 16 diagrams (a), (b), respectively by fitting the drive shaft cover of the support holder H ₁ preparative wearing flange plate 2 on the loading cavity 58 of the cover V, the fitting projection 55 and the holding projection FIG. 6 is an operation explanatory view of the state before and after overlapping with 61 as viewed from the back side of the cover V; Incidentally, FIG. 16 (b), in (b), for ease of understanding, the clamping projections 61 of the drive shaft supporting the holder H ₁ are hatched. For this reason, in order to attach the cover V to the drive shaft support holder H ₁ , as shown in FIG. 16A, the cover V is fitted into the insertion arrangement portion 63 on the drive shaft support holder H ₁ side. with arranging the engagement projection 55, by arranging the clamping projection 61 of the drive shaft supporting the holder H ₁ with the insertion arrangement portion 57 on the side of the cover V, drive shaft supporting the holder H ₁ in the loading cavity 58 of the cover V The drive shaft support holder H ₁ is rotated with respect to the cover V in a specific direction (clockwise as viewed from the back side of the cover V) with the cover mounting saddle plate 2 fitted. If is, as shown in FIG. 16 (b), becomes unrotatable clamping protrusion 61 side of the drive shaft supporting the holder H ₁ is in contact with the contact portion 56 on the side of the cover V, the drive shaft the housing space 62 between the flange plate 2 and the clamping projection 61 of the support holder H _1, a cover The fitting projection 54 is accommodated in the inserted state, and the fitting projection 54 is sandwiched between the rib plate portion 2 and the sandwiching projection 61, and the fitting projection 54 and the sandwiching projection 61 overlap each other. and a state, the cover V is attached to the drive shaft supporting the holder H _1. In this mounted state, the screw insertion hole 59 on the side of the cover V are consistent with one of a plurality of screws under the hole 64 formed in the flange plate portion 2 of the drive shaft supporting the holder H _1, screw 65 [Figures 1 and 12 (b) securing the bottom wall portion 52 of the cover V collar plate portion 2 of the drive shaft supporting the holder H ₁ with reference]. On the other hand, in removing the cover V from the flange plate 2 of the drive shaft supporting the holder H ₁ may be sequentially performed operations reverse to the above.

Therefore, in order to change the distance between the pair of blades K corresponding to the inner diameter (D) of the through hole B with respect to the wall plate such as the ceiling plate P, as shown in FIG. When rotating in this direction, the pinion shaft 26 constituting the pinion unit PU rotates in the same direction, and the pair of arm bodies A are synchronized with each other in the opposite direction with respect to the arm body mounting holder H ₂ by the same amount. Can be slid. For example, in FIG. 5, when the knob 28 is rotated in the direction of arrow F, the pair of arm bodies A are slid in the directions of arrows G and G ′. Here, since the pinion shaft 26 is supported by the arm body attaching holder H _{2 so} as to be orthogonal to the center axis S and close to the center axis S, a pair of the pinion shafts 26 is formed as described above. When changing the interval between the blades K, almost no rotational force is generated to rotate the center shaft S. For this reason, there is no fear that the pair of arm bodies A, that is, the pair of blade bodies K, rotate during the interval changing operation of the pair of blade bodies, and the change operation can be performed safely. In addition, the pinion shaft 26 is orthogonal to the protruding direction of each blade body K (direction parallel to the center axis S), and is disposed at a substantially central portion of each blade body K. Since it is possible to change the distance between the pair of blades K in a state where there is no risk of contact with each blade K, it is safe from this point.

Then, when performing drilling in the ceiling panel P to the drive shaft supporting the holder H ₁ by mounting the cover V, as shown in FIGS. 3 and 17, drilled in the drilling center J was scored in the ceiling board P The base end portion of the drive shaft 10 is electrically driven in a state where the drill portion 24 at the tip of the center shaft S of the tool C is applied and the vibration absorber 53 provided in the opening of the cover V is pressed against the ceiling plate P. The center shaft S is pressed by the electric drill E until it reaches the set cutting depth while being fitted to the drive shaft portion of the drill E and rotating the drive shaft 10. As shown in FIG. 3, since the tip of the center shaft S is disposed ahead of the tip of the pair of blade bodies K along the projecting direction of each blade body K, the center axis S is first drilled by the center shaft S. After that, the pair of blades K are gradually cut while rotating, whereby the through hole B having the set inner diameter (D) is drilled in the ceiling plate P without being misaligned. Although the chips are scattered at the time of drilling, since the drilled portion is sealed by the cover V, the chips are accommodated in the cover V without being scattered around. In addition, the chips tend to stay in the recesses 12b between the adjacent rack teeth 12a of the rack body 12 constituting the rack and pinion mechanism R, but the chips formed between the adjacent rack teeth 12a. Due to the presence of the powder discharge path 12c, the chips trying to stay between the recesses 12b slide down along the chip discharge path 12c and are discharged from the chip discharge port 12d, and therefore do not stay. .

Also, when drilling a small diameter hole in the wall of the ceiling board P, since the cover V may not be perforated holes in the setting position by interference with the wall plate, cover the drive shaft supporting the holder H ₁ V Is removed and the above drilling operation is performed. To remove the cover V from the drive shaft supporting the holder H _1, after removing the screws 65 which are attached to each other, for a drive shaft supporting the holder H ₁ and the cover V may only be rotated relatively, the cover The removal work of V is easy.

  Moreover, since the said Example is a structure in which the center axis | shaft S and a pair of blade body K advance and retreat integrally, in the middle of making the through-hole with respect to a wall board with a pair of blade body K, The center part is also drilled by the drill part 24 of the center shaft S. However, the center shaft moves forward together with the pair of blades until the drilling is started by the pair of blades K, and after the center position is determined by contacting the wall plate, The shaft is in contact with the wall plate and remains in the center position, and does not move any further, i.e., without drilling the wall plate, only a pair of blades move forward and drill a through hole. The present invention can also be implemented.

It is the perspective view which fractured | ruptured a part of punching tool C based on this invention. It is also a plan view. It is a front sectional view similarly. Is an exploded perspective view of a main part of the piercer C (portion excluding the drive shaft supporting the holder H ₁ and cover V). FIG. 4 is a perspective view of a state in which a pair of arm bodies A are slidably attached to the arm body attaching holder H ₂ by the same amount in opposite directions via a rack and pinion mechanism R and a fastening bolt 41. 3 is an exploded perspective view of a rack and pinion mechanism R. FIG. It is the XX sectional view taken on the line of FIG. It is the YY sectional view taken on the line of FIG. (A) and (B) are a partial perspective view and a cross-sectional view of the rack body 12 in which the chip discharge passage 12c is formed with one inclined surface, respectively. (A) and (B) are a partial perspective view and a transverse cross-sectional view of the rack body 12 in which the chip discharge passage 12c is formed with a mountain-shaped inclined surface, respectively. (A) and (B) are a partial perspective view and a cross-sectional view of the rack body 12 in which the recess 12b between the rack teeth 12a is formed deeply. (A) and (B) are a partial perspective view and a partial side view of the rack body 12 ′ in which the rack teeth 12 a ′ are each composed of independent protrusions N. The cover removed V from the drive shaft supporting the holder H ₁ is a partially cutaway perspective view from obliquely below. (B) is a view of the bottom wall 52 of the cover V from the outside, the (b) is a Z ₁ -Z ₁ line enlarged cross-sectional view of the same (b). (A) is the figure which looked at the cover mounting saddle plate part 2 of the drive shaft support holder H ₁ from the base end side of the center axis S, and (B) is Z ₂ -Z _{2 of} (B). It is a line expanded sectional view. (B) and (b) are respectively configured such that the cover mounting saddle plate 2 of the drive shaft support holder H ₁ is fitted into the fitting recess 58 of the cover V, and the fitting projection 55 and the clamping projection 61 are formed. It is action explanatory drawing which looked at the state before and behind overlapping from the back surface side of the cover V. FIG. It is a perspective view of the state which is performing the drilling operation | work with the punch C which concerns on this invention.

A: Arm body
C: Drilling tool
D: Distance between a pair of blades (perforation diameter)
H ₁ : Drive shaft support holder
H ₂ : Arm attachment holder
K: Blade
L: Chip
PU: Pinion unit
S: Center axis
V: Cover
10: Drive shaft
11: Arm body
12: Rack body
12a: rack teeth
26: Pinion shaft
27: Pinion
41: Tightening bolt

Claims (4)

A center shaft fixed to the arm body attaching holder, and extending in a direction perpendicular to the axial direction of the center shaft, are attached to the arm body attaching holder so as to be slidable in the extending direction. A pair of arm bodies, a pair of blade bodies attached to each arm body, and a drive shaft that is concentric with the center shaft and is integrally attached to the arm body attachment holder. A drilling tool comprising a drive shaft support holder ,
A pair of rack bodies respectively formed along the extending direction of the pair of arm bodies so that the concave and convex rack teeth can be opposed along the diagonally up and down direction;
A pinion unit attached to a pinion shaft provided perpendicular to the center axis in the arm body attaching holder, and the pinion is configured to mesh with each rack body at a portion whose phase is 180 ° different from each other; ,
A cover body mounted on the drive shaft support holder to cover the pair of blade bodies ;
With
The perforation diameter can be adjusted by changing the distance between the pair of blades attached to each arm body by sliding the pair of arm bodies in the reverse direction by the rotation of the pinion. Ingredients. 2. The punching device according to claim 1, wherein the pair of arm bodies is configured to be fixed to the arm body attaching holder via one tightening bolt. Wherein the drive shaft supporting the holder, the piercer according to claim 1 or 2, wherein the cover member is detachably mounted. In the rack body, the chips generated by drilling the pair of blade bodies are prevented from clogging in the recesses between the rack teeth, and the chips entering the recesses are allowed to pass through and be discharged. The chip discharge path provided in communication with the recess toward the opposite side of the rack teeth in the recess, and the side of the rack body to discharge the chips in the chip discharge path to the outside of the rack body 4. The punching tool according to claim 1, further comprising a chip discharge port provided in communication with the chip discharge path on a side facing the rack teeth.

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