JPH09285932A - Blade exchanging apparatus and blade exchanging auxiliary apparatus for rotary cutting tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a hand of a worker from getting close to a center drill or a cutting blade so as to safely replace a blade without any fear of injury by providing a fitting holding part for a base part side fitting part of a center drill at the tip of a body part, in which the center drill is passed and stored, and providing an operation unit rotating the body part. SOLUTION: The inside of a body part 25 formed into a cylinder serves as a space in which the front end side from a fitting part 16 of a center drill 13 is passed and stored. A fitting holding part 26, which is formed into a hexagonal cylinder shape to be fitting in the fitting part 16 in the center drill 13, is integrally arranged in the tip of the body part 25. A rod type operation handle 27 is passed through freely removably into an insertion hole 28 on the base part side of the body part 25. While the center drill 13 is passed and stored inside the body part 25, the fitting holding part 26 is fitted in the fitting part 16 in the center drill 13, and then, rotational operation is carried out and the center drill 13 is fastened/loosened. Therefore, a hand of a worker is prevented from approaching the center drill 13 or a cutting edge 12, so that a fear of injury is eliminated and a cutter can be replaced safely.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a center drill in which a mounting screw portion on the base side is screwed and attached to the tip of a drive shaft which is rotationally driven, and a center drill which is sandwiched between the center drill and the drive shaft. In a rotary cutting tool having an L-shaped or substantially U-shaped cutting blade, a blade exchanging tool used for exchanging the center drill and the excavating blade and a center exchanging tool when the center drill is removed. The present invention relates to a blade replacement aid for assisting work.

[0002]

2. Description of the Related Art In recent years, there have been provided rotary cutting tools for making holes in a wall surface when attaching an outlet or the like to the wall. This is because the center drill is attached to the tip of the drive shaft that is driven to rotate by screwing the mounting screw part on the base side, and an L-shaped or U-shaped cutting blade is installed between the center drill and the drive shaft. It is attached by sandwiching it, and a cover is provided so as to surround the center drill and the cutting blade.
When exchanging the center drill or cutting blade with such a rotary cutting tool, the center drill is rotated to attach or detach the center drill, but conventionally when loosening or tightening the screw of the mounting screw of the center drill. It was done by fitting a wrench to the hexagonal fitting part of the center drill.

[0003]

However, in the above-mentioned conventional example, it is necessary to loosen or tighten with a wrench near a cutting tool such as a cutting blade or a center drill, and an operator is injured. There is a risk of In particular, the center drill has a problem that it is difficult to replace it by loosening or tightening it because it protrudes for a long time, and moreover, there is a problem that the tip of the center drill is easily injured.

Further, when rotating the center drill with a wrench as in the prior art, the drive shaft also rotates together with the center drill, and it is difficult to rotate the center drill with respect to the drive shaft. I need to stop. In other words, when rotating the center drill with a wrench, unless the rotation of the drive shaft is stopped, the drive shaft also turns and the mounting screw cannot be loosened or tightened. In order to prevent the drive shaft from rotating, a gear that transmits the rotation to the drive shaft is provided with a lock device that locks the rotation of the gear.However, if the structure that locks the gear is adopted, the structure becomes complicated. In addition, if the lock device is provided, it is necessary to provide a long hole in the safety cover in order to allow the operating portion for operating the lock device to pass through, and there is a risk that the working environment is deteriorated due to leakage of cutting powder.

The present invention has been made in view of the above-mentioned points, and makes it possible to easily and safely attach and detach the center drill, and to rotate the center drill to attach and detach it around the drive shaft. The task is to make it easy to stop.

[0006]

In order to solve the above problems, in the blade exchanging tool of the first feature of the present invention, a mounting screw portion on the base side is screwed and attached to the tip of a drive shaft which is rotationally driven. A blade exchanging tool used for attaching and detaching a center drill of a rotary cutting tool, which has a center drill and a substantially L-shaped or U-shaped cutting blade sandwiched between the center drill and a drive shaft, A body part that allows the center drill to be inserted and stored therein, a fitting holding part that is provided at the tip of the body part and that can be fitted into a fitting part on the base side of the center drill, and an operation that rotates the body part. And a section. The blade exchanging tool configured in this way fits the fitting holding part to the fitting part of the center drill while the center drill is inserted and stored in the body part, and the blade exchanging tool is rotated in this state. You can loosen or tighten the center drill. Therefore, the worker's hand does not approach the center drill or the cutting blade, and the blade can be safely replaced without the risk of injury.

The blade exchanging tool of the second feature of the present invention is a blade exchanging tool for attaching and detaching a center drill of a rotary cutting tool in which a center drill and a cutting blade are respectively provided on a pair of drive shafts which are interlocked with each other. In this case, the body portion is provided with a rotation stopping means for preventing the drive shaft from rotating by being entangled with the cutting blade and the center drill. In this case, when the center drill is inserted and stored in the body part of the blade changer, and the blade holder is rotated while the fitting holder is fitted in the fitting part of the center drill, The drive shaft can be stopped by entwining the anti-rotation device provided on the part with the cutting blade and the center drill, and the drive shaft can be easily stopped and the drive shaft can be stopped to loosen or tighten the center drill. The rotating operation can be done easily.

Further, the blade exchange assisting tool of the present invention is sandwiched between a center drill and a center drill in which a base side mounting screw portion is screwed and attached to a tip end of a drive shaft which is rotationally driven. A blade used for attaching and detaching a center drill of a rotary cutting tool having a substantially L-shaped or U-shaped cutting blade and a center drill and a cover surrounding the periphery of the cutting blade with the blade exchanging tool of the first feature. A replacement aid,
The lid body detachably attached to the opening of the cover is provided with a rotation stopping means for stopping rotation of the center drill and the cutting blade, and a through hole through which the blade exchanging tool of the first characteristic can be inserted. To do. In this case, by attaching the lid of the blade replacement aid to the opening of the cover, the cutting blade is stopped by the rotation stopping means to prevent the drive shaft from rotating, and in this state, insert the blade replacement through the through hole of the lid. The center drill can be loosened or tightened by rotating the blade changer. in this case,
The rotation of the drive shaft can be stopped and the operation of loosening or tightening the center drill with the blade changer can be done easily, and by covering the opening of the cover, you can further prevent the cutting blade and center drill from touching your hands. You can work safely.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIGS. 4 to 6 show a rotary cutting tool. The housing 1 of the outer shell of the rotary cutting tool A is composed of a cylindrical grip 2 on the base side and a cover 3 with a large diameter on the tip side. A mechanical case 4 is internally provided in the cover 3, and a spring receiving member 5 and a spring receiving body 6 are internally provided in the grip 2. The mechanism case 4 is not rotated with respect to the cover 3, but is movable in the axial direction. The spring receiving member 5 is provided integrally with the housing 1. The spring receiver 6 is prevented from rotating with respect to the grip 2, but is movable in the axial direction. Rotating shaft 9
Is arranged at the center of the rotary cutting tool A, and is inserted into the shaft hole of the spring receiving member 6, the shaft hole of the spring receiving member 5, and the mechanism case 4. The rotary shaft 9 is rotatably inserted in the shaft hole of the spring receiver 6, but is stopped by a pair of locking rings 7 so that the spring receiver 6 does not slide in the longitudinal direction with respect to the rotary shaft 9. There is. A rotary shaft 9 is rotatably and slidably inserted in the shaft hole of the spring receiving member 5. The tip of the rotary shaft 9 is supported by a bearing 8 in the mechanism case 4. A coil spring 10 is interposed between the spring receiving member 5 and the spring receiving body 6 on the outer circumference of the rotary shaft 9 and biases the spring receiving member 5 and the spring receiving body 6 in a direction in which they are separated from each other. The base end of the rotary shaft 9 is connected to a chuck of an electric rotary tool such as an electric screwdriver so as to be rotationally driven.

The mechanism case 4 has 180
The drive shaft 11a and the drive shaft 11b are rotatably mounted so as to be rotationally symmetrical. A cutting blade 12 and a center drill 13 are attached to the tips of the drive shafts 11a and 11b, respectively. The cutting blade 12 is formed in a substantially U shape, and has a through hole 14 formed in a substantially D shape in the center thereof. The cutting blade 12 may be substantially L-shaped. The center drill 13 has a drill portion 15 at the tip as shown in FIG.
A hexagonal fitting portion 16 is provided on the base side, and a mounting screw portion 17 is provided on the base end. A mounting screw hole 18 is formed at the tip of each of the drive shafts 11a and 11b, and the detent portion 1 having a substantially D-shaped outer shape is formed in the opening of the mounting screw hole 18.
9 is projected. By inserting the insertion hole 14 of the cutting blade 12 into the anti-rotation protrusion 19 and screwing the mounting screw portion 17 of the center drill 13 into the mounting screw hole 18, the cutting blade 1
2 and the center drill 13 are attached together to the drive shafts 11a and 11b. On the contrary, by removing the center drill 13, the cutting blade 12 can be removed together with the center drill 13. The pair of cutting blades 12 are attached in directions orthogonal to each other. Further, the tip of the center drill 13 is projected to the tip side from the tip of the cutting blade 12. A gear 20 is mounted on the outer periphery of the rotary shaft 9 in the mechanism case 4, and a gear 21 is integrally mounted on the base side of the drive shaft 11a, and the gear 21 and the gear 20 are meshed with each other. A gear 22 is attached to the tip end side of the drive shaft 11a, and a gear 23 is attached to the tip end side of the drive shaft 11b so that the gear 22 and the gear 23 are meshed with each other. When the gear 20 is driven by the rotary shaft 9, the drive shaft 11a is driven via the gears 20 and 21, the drive shaft 11b is driven via the gears 22 and 23, and the cutting blade 12 and the center drill 13 are driven. Are being driven.

When a hole is cut by the rotary cutting tool A constructed as described above, it is carried out as follows. When the tip of the center drill 13 is brought into contact with the object to be cut and the rotary shaft 9 is driven to rotate, a center hole is drilled by the center drill 13 and a circular hole is drilled by the cutting blade 12 around the center hole. At this time, as the center drill 13 and the cutting blade 12 move in the tip direction, the cover 3 whose tip abuts the object to be cut is relatively retracted toward the base side against the coil spring 10.

The center drill 13 of the rotary cutting tool A thus constructed is operated by attaching and detaching the center drill 13.
A blade exchanging tool B for exchanging the cutting blade 12 and the cutting blade 12 is configured as shown in FIGS. That is, the blade changer B is mainly composed of the body portion 25, the fitting holding portion 26, and the operation handle 27. In the present example, the body portion 25 is formed in a cylindrical shape, and the inside thereof is the fitting portion 1 of the center drill 13.
6 is a space through which the tip side can be inserted and stored.
The fitting holding portion 26 is formed in a hexagonal tubular shape that fits into the fitting portion 16 of the center drill 13, and is integrally provided at the tip of the body portion 25. The operation handle 27 has a rod shape and is inserted into an insertion hole 28 on the base side of the body portion 25 so as to be freely inserted and removed. Further, in the case of this example, the body portion 25 of the blade changer B is provided with a rotation stop plate 29 as a rotation stop means. The rotation stop plate 29 is an elongated rectangular plate and has an annular connecting portion at the base. The body 30 is rotatably fitted in the body portion 25.

When the blade is exchanged by using the blade exchanging tool B having the above-mentioned configuration, the following operation is performed. When replacing one of the two sets of center drills 13 and cutting blades 12, insert one of the center drills 13 so as to cover the body portion 25 of the blade exchanging tool B as shown in FIG. The part 26 is fitted to the fitting part 16 of the center drill 13,
As shown in FIG. 3, the rotation stop plate 29 is entangled with the other center drill 13 and the cutting blade 12, and in this state, the operation handle 27
And operate the blade changer B to rotate the center drill 13
Loosen the mounting screw 17 by rotating the
The cutting blade 12 is removed by removing the center drill 13 and the center drill 13. Then, a new center drill 13 and a cutting blade 12 are prepared, the center drill 13 and the cutting blade 12 are set by an operation reverse to the above, and the center drill 13 is fastened and fixed. When loosening or tightening the center drill 13, it can be performed while the center drill 13 is inserted and stored in the body portion 25 of the blade changer B, so it can be performed safely without injury. You can Further, when the center drill 13 is loosened or tightened by rotating the blade changer B, the drive shafts 11a and 11b rotate because the rotation stop plate 29 is entwined with the other center drill 13 and the cutting blade 12. The center drill 13 is blocked, and the center drill 13 can be easily loosened or tightened by rotating only the center drill 13. When replacing both the two sets of center drills 13 and cutting blades 12, one of the center drills 13 can be loosened to the extent that it can be manually rotated as described above, and then the other center drill 13 can be manually rotated. Loosen to some extent, turn both center drills 13 by hand, remove them, set a new center drill 13 and cutting blade 12 by the reverse operation to the above, and tighten and fix the center drill 13.

FIG. 8 shows another example of the blade changer B. In the case of this example, the body portion 25 of the blade changer B is formed by the side piece portions 25a on both sides obtained by bending the strip plate into a flat and substantially U-shape, and the tip of the body portion 25 is fitted in a square shape. A fitting holding portion 26 that fits into the portion 16 is provided. Also in this case, the center drill 13
When loosening or tightening the center drill 13
The tip end side of the fitting portion 16 is housed between the side piece portions 25a on both sides to ensure safety, and the square fitting portion 16 of the center drill 13 is fitted with the fitting holding portion 26 to fit the center. The drill 13 can be rotated.

9 and 10 show another example of the blade changer B.
In the case of the example of FIG. 9, a fitting hole 31 that can be fitted to the fitting portion 16 of the adjacent center drill 13 is provided at the tip of the rotation stop plate 29. In the case of the example of FIG. 10, the rotation stop plate 29 is provided with two fitting holes 32 for fitting the two cutting blades 12. Also in these cases, the rotation preventing plate 29 is used to drive the drive shafts 11a, 11
With the rotation of b stopped, the blade changer B can be rotated to loosen or tighten the center drill 13.

FIG. 11 shows another embodiment. In the case of this example, the blade exchanging tool B that does not have the above-described rotation stop plate 29
The center drill 13 is attached / detached with a blade replacement aid C instead of the rotation stop plate 29. The blade replacement assisting tool C is provided on the lid 33 so as to prevent the blade 34 from rotating.
And a through hole 35 are provided. The lid 33 is detachably mounted so as to close the opening of the cover 3, is formed in a rectangular plate shape, and is provided with a fitting edge 36 that can be fitted to the opening edge in the periphery. The rotation-stopping cylinder portion 34 has an elliptic cylindrical shape and is integrally provided on the back surface of the lid body 33 to prevent the cutting blade 12 from rotating. The through hole 35 is the lid 3
Center drill 1 when 3 is attached to the opening of cover 3
It is provided so as to penetrate the position corresponding to 3. Then, the cover 33 of the blade exchange assisting tool C is attached to the opening of the cover 3, the cutting blade 12 is prevented from rotating by the rotation preventing tubular portion 34 to prevent the drive shafts 11a and 11b from rotating, and the blade is exchanged in this state. By inserting the tool B through the through hole 35 and rotating the blade changing tool B, the center drill 13 is loosened or tightened. In this case, the center drill 13 can be loosened or tightened in a state where the opening of the cover 3 is closed by the lid 33, so that the safety can be further improved.

A rotary cutting tool A constructed as described above.
When making a hole in the wall, the hole is made at a position corresponding to the wiring box 37 embedded in the wall. At this time, it is necessary to detect the position of the wiring box 37 in the wall and make the hole accurately. That is, in order to detect the position of the wiring box 37, the magnet 3 is placed in the wiring box 37 embedded in the wall.
8 is attached and the position of the wiring box 37 is magnetically detected from the surface side of the wall. FIG.
FIG. 13 shows a structure in which the magnet 38 is attached to the wiring box 37. Attachment parts 40 to the wiring box 37 are provided at both ends of the strip-shaped magnet attachment plate 39, and the attachment parts 40 are provided with boss portions 41 which can be inserted into and fitted into the attachment screw holes of the wiring box 37. The magnet mounting plate 39 is provided and the magnet mounting plate 39 can be installed in the wiring box 37 by mounting the mounting portion 40 to the wiring box 37 by fitting the boss portion 41. A cylindrical magnet holding cylinder 42 is provided at the center of the magnet mounting plate 39 in the longitudinal direction, and a locking edge 44 is provided at the edge of the opening 43 on the front side of the magnet holding cylinder 42. A loose elastic loose piece 45 is provided on the rear side of 42, and a locking claw 46 is provided at the tip of the elastic loose piece 45. The magnet 38 is formed in a cylindrical shape, and the magnet 38 is inserted and held in the magnet holding cylinder 42. At this time, the front end of the magnet 38 is locked by the locking edge 44.
And the rear end of the magnet 38 is held by the locking claw 46 at the tip of the elastic loose piece 45 being locked. Conventionally, since the magnet 38 was held only by being inserted into the magnet holding cylinder 42, the magnet 38 may come off when a bending or twisting force is applied to the magnet mounting plate 39, but in the case of the present invention, as described above. By locking the locking claw 46 at the tip of the elastic loose piece 45, the magnet 38 can be securely attached so as not to come off.

[0018]

According to the blade exchanging tool of the first aspect of the present invention, the center drill having the mounting screw portion on the base side screwed to the tip of the rotationally driven drive shaft, and the center drill and the drive shaft are attached. A blade exchanging tool for attaching and detaching a center drill of a rotary cutting tool having a substantially L-shaped or U-shaped cutting blade sandwiched between the blades, and the center drill can be inserted and stored inside. Since the body portion, the fitting holding portion that is provided at the tip of the body portion and can be fitted into the fitting portion on the base side of the center drill, and the operation portion that rotates the body portion are provided, With the center drill inserted and stored in the body part, the fitting holding part is fitted to the fitting part of the center drill, and in this state the blade changer can be operated to loosen or tighten the center drill. The worker's hand is centered Without approaching or cutting blade, in which injury can work without fear safety tool exchange or the.

The blade exchanging tool according to a second aspect of the present invention is a blade exchanging tool used for attaching and detaching a center drill of a rotary cutting tool in which a center drill and a cutting blade are provided on a pair of drive shafts which are interlocked with each other. Since the body part is provided with a rotation stop means that locks the drive shaft against the cutting blade and center drill, the center drill is inserted and stored in the body of the blade changer. When rotating the blade changer with the part fitted into the fitting part of the center drill, the rotation prevention means provided on the body of the blade changer is entwined with the cutting blade and the center drill to rotate around the drive shaft. It can be stopped, and the rotation of the drive shaft can be easily stopped and the rotation operation of loosening and tightening the center drill by stopping the rotation of the drive shaft can be easily performed.

The blade exchange assisting tool according to claim 3 of the present invention is
A center drill in which a mounting screw portion on the base side is screwed and attached to the tip of a drive shaft that is rotationally driven, and a substantially L-shaped or U-shaped cutting blade that is sandwiched between the center drill and the drive shaft. And a center drill of a rotary cutting tool having a center drill and a cover that surrounds the periphery of the cutting blade, which is a blade exchange assisting tool used when the blade exchanging tool according to claim 1 is attached and detached, and is detachably attached to an opening of the cover. A rotation stopping means for stopping rotation of the center drill and the cutting blade on the lid that can be mounted,
Since the through hole through which the blade exchanging tool of claim 1 can be inserted is provided, the cutting blade is stopped by the detent means by attaching the lid body of the blade exchanging assist tool to the opening of the cover to detent the drive shaft. In this state, the blade changer can be inserted through the through hole of the lid, and the blade changer can be rotated to loosen or tighten the center drill. You can easily loosen and tighten the center drill with the blade changer, and by covering the opening of the cover, you can further prevent the cutting blade and center drill from touching your hands and work more safely. Is something that can be done.

[Brief description of drawings]

FIG. 1 is a partially cutaway sectional view showing a state where a blade exchanging tool according to an embodiment of the present invention is set on a center drill.

FIG. 2 is a perspective view of the blade changer of the above.

FIG. 3 is a perspective view showing a state in which the above blade exchanging tool is set on a rotary cutting tool.

FIG. 4 is a sectional view of the above rotary cutting tool.

FIG. 5 is a perspective view showing a state in which a cover portion of the above rotary cutting tool is seen through.

FIG. 6 is an enlarged perspective view of a cutting blade and a center drill of the above rotary cutting tool.

FIG. 7 is a perspective view of the center drill of the above.

FIG. 8 is a perspective view of another example of the blade changing tool of the above.

FIG. 9 is a plan view showing another example of the blade changing tool of the above.

FIG. 10 is a plan view showing another example of the blade changing tool of the above.

FIG. 11 is a perspective view showing another example of the above embodiment, in which (a) is a state in which a blade exchange assisting tool is set on a rotary cutting tool,
(B) is a perspective view seen from the back side of the blade replacement aid.

FIG. 12 is a perspective view showing a state in which a magnet mounting plate is attached to the above wiring box.

FIG. 13 is a partially cutaway perspective view showing an enlarged main part of the same.

FIG. 14 is a cross-sectional view showing a state where a magnet is held in the magnet holding cylinder of the above.

[Explanation of symbols]

 A rotary cutting tool B blade changer C blade changer 3 cover 11a drive shaft 11b drive shaft 12 cutting blade 13 center drill 16 fitting part 17 mounting screw part 25 body part 26 fitting holding part 29 whirl stop plate 33 lid 34 Non-rotating cylinder part 35 Through hole

Claims (3)

[Claims] 1. A center drill in which a base side mounting screw portion is screwed and attached to a tip of a rotationally driven drive shaft, and a substantially L-shape or a substantially U shape sandwiched between the center drill and the drive shaft. A blade changer used for attaching and detaching a center drill of a rotary cutting tool having a V-shaped cutting blade,
A body part that can be stored by inserting the center drill inside,
A blade of a rotary cutting tool, comprising: a fitting holding portion provided at a tip of a body portion and capable of being fitted into a fitting portion on a base portion side of a center drill; and an operating portion for rotating and operating the body portion. Exchange tool. 2. A blade exchanging tool for attaching and detaching a center drill of a rotary cutting tool, wherein a center drill and a cutting blade are provided on a pair of drive shafts which are interlocked with each other, and which is entangled with the cutting blade and the center drill. 2. A blade exchanging tool for a rotary cutting tool according to claim 1, wherein a rotation stopping means for stopping rotation of the drive shaft is provided on the body portion. 3. A center drill in which a mounting screw portion on the base side is screwed and attached to the tip of a drive shaft that is rotationally driven, and a substantially L-shape or a substantially U shape sandwiched between the center drill and the drive shaft. A blade exchange assisting tool used when attaching and detaching a center drill of a rotary cutting tool, which has a V-shaped cutting blade and a center drill or a cover surrounding the cutting blade, with the blade exchanging tool according to claim 1. A blade exchange assisting tool, comprising: a lid body that can be detachably attached to the base body; and a rotation stopping means that prevents a center drill and a cutting blade from rotating, and a through hole that allows the blade exchange tool of claim 1 to be inserted therethrough. .