JPH09183006A - Device for preventing drill from projecting abruptly - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the drill of an electric drill device from projecting abruptly out of a through hole. SOLUTION: A holding tool 8 is freely rotationally mounted on a support plate 7 via a bearing 12, and expansion rods 14 that are made to constantly work in an expanding direction are mounted on the support plate 7. Abutting plates 15 are secured to the end faces of the expansion rods 14. A drill 3 held by the chuck of an electric drill device has its end inserted into a holding tool 8 and strongly held so that the drill 3 and the holding tool 8 rotate integrally with each other. To bore a hole in a base material the abutting plates 15 are pressed against the surface of the base material and the electric drill device is operated and pressed against the base material to allow the drill 3 to enter the base material as the expansion rods 14 contract. Since the expanding forces of the expansion rods 14 work even at the moment when the drill 3 is forced through the base material, the inertia of the pressing forces can be canceled out.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chuck for a drill when a through hole is formed in a wall surface or the like of an electric drill device by the inertia force of the pressing force applied to the electric drill device at the moment when the tip of the drill penetrates the wall surface. The present invention relates to a drill sudden protrusion prevention device used to prevent a heavy collision with a wall surface.

[0002]

2. Description of the Related Art When a through hole is formed in a hole forming base material such as a steel plate having a certain thickness, a wooden board, or a wall surface of a building,
Conventionally, as shown in FIG. 8, a through hole 5 having a desired size is provided.
Using the electric drill device 1 in which the drill 3 having a size corresponding to the inner diameter of the drill 2 is attached to the chuck 2, the worker 6 applies the cutting edge of the drill 3 to the scribing position on the surface of the base material 4 for punching, In addition, the drill 3 is positioned so as to be perpendicular to the surface of the base material 4 and the electric drill device 1 is rotationally driven, and the pressing force F of a magnitude necessary for the electric drill device 1 is applied.
Through holes 5 are formed in the base material 4 while imparting.

[0003]

However, since the drilling is performed while applying a pressing force to the electric drilling device as described above, it is applied to the electric drilling device 1 at the moment when the drill 3 penetrates the base material 4. The reaction force from the base material 4 against the pressing force F suddenly disappears, and even if the worker 6 momentarily loosens the pressing force F, the drill 3 suddenly projects from the through hole 5 due to the inertial force, and the electric drill The tip of the chuck 2 of the device 1 may collide with the base material 4 and damage the surface of the base material 4, or the drill 3 may collide with an object on the back side of the base material 4, which is a situation. In order to prevent this, the cutting edge of the drill 3 is conventionally the base material 4
When it is felt that it is about to penetrate, the pressing force F on the electric drill device 1 is consciously weakened, and the intuition and experience of the worker 6 are large and do not always succeed. There was a problem.

Therefore, the present invention is to provide a drill sudden protrusion preventing device capable of canceling the inertia force of the pressing force at the moment when the tip of the drill penetrates the base material.

[0005]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention rotatably mounts a support plate through which a gripping tool for gripping a drill so that the drill can be integrally rotated is passed through. A contact plate for attaching a telescopic rod adapted to act in the extending direction so as to be parallel to the gripping tool, and applying a base material for perforating at the tip of the telescopic rod Is fixed.

When the abutting plate is applied to the base material and the electric drill device is driven to push the electric drill device against the base material with a pressing force that overcomes the force of the expandable rod to expand, the expandable rod contracts. Since the tip of the drill hits the base material and drilling is performed,
A hole is made in the base material by pushing the drill with a pressing force that overcomes the extension force of the telescopic rod. At the moment when the tip of the drill penetrates the base metal, the elastic force of the telescopic rod that is trying to extend acts as a reaction force against the pressing force that was being applied to the electric drill device, so the drill is pushed all at once. And the chuck of the electric drill does not collide with the base material.

If a scale plate for measuring the amount of contraction of the telescopic rod is provided, the telescopic rod is compressed by the same force as the depth of the hole due to the pressing force applied to the electric drill device. You can easily know the depth of the holes that have been drilled.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. 1 (a) (b) (c) and FIG. 2
1 shows an embodiment of the present invention, in which a circular opening provided in the central portion of a disk-shaped support plate 7 has an inner diameter slightly larger than the outer diameter of the drill 3 on one end side. The other end side of the gripping tool main body 11 is formed by forming a taper part on the taper part, engraving the male screw 9 on the taper part, and providing a plurality of (four in the figure) vertical slits 10 at required places in the circumferential direction. Then, the gripping tool main body 11 is rotatably mounted via a bearing 12, and an inner taper tightening nut 13 is screwed onto the male screw 9 of the taper portion of the gripping tool main body 11.
The gripping tool 8 is configured such that one end of the gripping tool is tightened.
In addition, a plurality of (three in the figure) telescopic rods 14 are arranged on the support plate 7 so as to always extend in the peripheral direction in parallel with the gripping tool 8 at equal intervals in the circumferential direction. So that each telescopic rod 14 is attached.
A disk-shaped contact plate 15 having a central portion opened is fixed to the tip of the contact plate 15, and the cushioning material 1 is attached to the surface of the contact plate 15.
Make sure to attach 6.

The telescopic rod 14 has a large-diameter cylindrical body 17 in which the abutment plate 15 is fixed to one end surface, and a small-diameter cylindrical body 1 in which the other end is fixed to the support plate 7.
One end of 8 is slidably fitted so that it can be expanded and contracted, and one spring 19 is provided in both cylinders 17 and 18.
Is compressed and housed so that the force is always acting in the direction in which the cylinders 17 and 18 extend, and the disk-shaped pressing member 20 is attached to the other end of the cylinder 18 having the small diameter. Is housed slidably in the axial direction, and a spring 19 is interposed between the pressing member 20 and one end of the large-diameter cylindrical body 17, and the screw rod 21 inserted from the outside is pressed against the above. The strength of the spring 19 can be adjusted by screwing into the member and rotating the screw rod 21 to push and pull the pressing member 20. In FIG. 1 (a), 17a and 18a indicate stoppers for preventing the telescopic rod 14 from slipping out when the telescopic rod 14 reaches the maximum extension.

When performing a drilling operation, the tightening nut 13 of the gripping tool 8 is loosened and then the tip side of the drill 3 is inserted into the gripping tool main body 11 so that the cutting edge of the drill 3 is larger than the contact plate 15. The tightening nut 13 of the gripping tool 8 is tightened in a state where it is retracted somewhat. Since a plurality of vertical slits 10 are provided in the tapered portion of the gripping tool main body 11, the tightening nut 13 is attached to the male screw 9
By tightening along the direction, the tip side of the grasping tool body 11 is clamped and the drill 3 is firmly grasped, and the drill 3 and the grasping tool 8 can be rotated as a unit.

Next, the electric drill device 1 is set so that the contact plate 15 is applied to the scribing position on the surface of the base material 4 via the cushioning material 16, and the electric drill device 1 is directed toward the base material 4. If you push it by pressing,
Is contracted by the pressing force F (see FIG. 2) so that the tip of the drill 3 can be brought close to the base material 4, and the electric drill device 1 is slowly pressed against the base material 4 to rotate the drill 3 to the base material 4. The position of the abutment plate 15 is finely adjusted while bringing the surface of the material 4 close to the surface to match the drill 3 with the marking position, and then the switch is turned on to rotate the electric drill device 1 and then the base material 4 8 is pressed, the drill 3 is rotated integrally with the grasping tool 8 and the telescopic rods 14 are contracted so that the tip of the drill 3 bites into the base material 4 and is shown in FIG. The through hole 5 can be formed in exactly the same manner as the conventional case. At this time, at the moment when the tip of the drill 3 penetrates the base material 4, the spring 21 in each telescopic rod 14 replaces the reaction force from the base material 4 against the pressing force F that has been applied to the electric drill device 1 up to that point. Since the elastic force is exerted on the electric drill device 1, the inertia force of the pressing force F can be canceled by the elastic force of the spring 19 and the drill 3 can be prevented from suddenly protruding from the through hole 5. it can.

In the above, the base material 4 and the contact plate 15
Since the cushioning material 16 is interposed between and, it is possible to prevent the surface of the base material 4 from being scratched, and moreover, the contact plate 15, the telescopic rod 14, the support plate 7, and the grip plate. Since the drilling is performed while the drill 3 is supported on the surface of the base material 4 via the tool 8, the drill 3 can be kept in a stable state and is perpendicular to the base material 4. Through holes 5 can be opened.

Next, FIG. 3 shows another embodiment of the present invention. In the same construction as shown in FIGS. 1 (a), (b), (c) and FIG. 2, a cylindrical grip is provided. When using a drill 3 having an outer diameter smaller than the inner diameter of the tool body 11, an inner diameter of the drill 3 slightly larger than the outer diameter of the drill 3 and a grip tool are provided in the annular gap between the inner surface of the tool body 11 and the outer surface of the drill 3. The gripper body 11 has an outer diameter slightly smaller than the inner diameter of the body 11.
The grip body 1 is attached to one end of the sleeve which is slightly longer than
The vertical slits 22 having the same length as the vertical slits 10 provided in the first taper portion are intervened by an attachment 23.

In the case of the embodiment shown in FIG. 3, the attachment 23 is inserted into the grasping tool body 11.
3, the vertical slit 22 and the vertical slit 10 of the gripper main body 11 are inserted so that they are aligned with each other, and the drill 3 is inserted into the attachment 23. When 13 is screwed and tightened, the slit forming portion of the gripping tool main body 11 is tightened together with the forming portion of the vertical slit 22 of the attachment 23 to be reduced in diameter, so that the gripping tool main body 11 is attached via the attachment 23. The drill 3 can be firmly gripped, and the drill 3 can be used in exactly the same manner as the embodiment shown in FIGS. 1 (a), (b), (c), and FIG. Any attachment having a smaller outer diameter than the inner diameter of the gripper body 11 can be obtained by using a plurality of attachments that are slightly smaller than the inner diameter and have different wall thicknesses. Can use a drill 3 such sizes, it is possible to effectively utilize a single abrupt projecting prevention device.

Next, FIG. 4 shows still another embodiment of the present invention. The same surface side of the support plate 7 showing the embodiment of FIG. 1 (a) (b) (c) and FIG. Grasping tool 8
The gripping tool 8 is provided on the surface opposite to the mounting side of the telescopic rod 14, instead of the structure in which the gripping tool 13 is tightened. Has the advantage that it can be performed easily.

FIG. 5 shows an application example of the present invention.
In the same configuration as the above embodiment, the support plate 7
A scale plate 24 having a length reaching the large-diameter cylinder 17 of the telescopic rod 14 is provided in the vicinity of any one of the telescopic rods 14, and a pointer 25 is attached to the end of the cylinder 17. It is a thing.

In the case of the embodiment shown in FIG. 5, in the drilling process, as the cutting of the base material 4 by the drill 3 of the electric drill device 1 progresses and the hole becomes deeper, the telescopic rod 14 becomes larger.
Is contracted by the same length as the depth of the hole, the length of contraction of the telescopic rod 14 is read as the moving distance of the cylindrical body 17 by the scale plate 24 and the pointer 25, and the depth of the hole already cut Can be easily known, and the pressing force F applied to the electric drill device 1 immediately before the cutting edge of the drill 3 penetrates the base material 4 can be weakened and the inertia force can be suppressed. This is effective not only in the case of cutting through holes 5 but also in the case of cutting a dead end hole.

Next, FIG. 6 shows another application example of the present invention, in which the gripper main body 11 is rotatably supported by a bearing at an eccentric position of the disc-shaped support plate 7, and the support plate 7 is One or a plurality (a single case is shown in the figure) of the telescopic rods 14 are attached to the projecting side surface of the grasping tool body 11, and a horseshoe-shaped contact plate 15 'is attached to the tip of the telescopic rods 14. The scale 1 is fixed, and a scale plate 24 is attached to the support plate 7 in the vicinity of the telescopic rod 14 in parallel with the telescopic rod 14 and the tubular body 1 of the telescopic rod 14 is fixed.
A pointer 25 is attached to the end portion of 7 to read the contraction amount of the telescopic rod 14 on the scale of the scale plate 24. Further, when a hole is made horizontally, a leveler 26 is attached at an intermediate position of the cylindrical body 17. It has a different configuration. If a hole is to be formed vertically downward, the leveler 26 is placed on the support plate 7.

In the case of the embodiment shown in FIG. 6, it is possible to obtain the same operation and effect as those of the above-described embodiment, and when making a hole in the horizontal direction, the large-diameter cylindrical body 17 of the telescopic rod 14 is provided. It is possible to carry out the drilling work while confirming the horizontal state by the leveler 26 attached to the.

The present invention is not limited to the above-mentioned embodiment, and for example, the case where both the cylindrical bodies 17 and 18 constituting the telescopic rod 14 are cylindrical is shown. The cylindrical bodies 17 and 18 may have a rectangular tubular shape, and in the embodiment shown in FIGS. 1C and 3, the grasping tool 8 has a male screw 9 formed on a taper portion on one end side. The case is shown in which the inner taper shape tightening nut 13 is screwed into the gripping tool main body 11 and tightened. As shown in FIG. 7A, the slit forming portion of the gripping tool main body 11 is flat. The inner surface of the tightening nut 13 has a flat inner surface as shown in FIG. 7B. As writing because, gripper body 11
Can make either one of the tightening nuts 13 a flat surface, and further, in the embodiment shown in FIGS. 1 to 6, a leveler can be mounted on the telescopic rod 14 or the support plate 7 according to the usage condition. That can be installed,
In addition, it goes without saying that the present invention can be variously modified without departing from the scope of the invention.

[0021]

As described above, according to the drill sudden protrusion preventing apparatus of the present invention, the support plate is rotatably attached with the gripping tool for gripping the drill, and the force is exerted so that the tool always springs in the extending direction. Of the present invention by attaching a telescopic rod which is designed to operate in a perpendicular direction, fixing a contact plate to the tip of the telescopic rod, and allowing the drill of the electric drill device to firmly grasp the grasping tool. The device is attached to the drill, and the electric drill device is pressed against the base material while applying the abutting plate to the base material to perform the drilling process, so at the moment the drill tip penetrates the base material. The extension force of the telescopic rod acts against the pressing force that was applied to the electric drill until then, and the inertia force of the pressing force can be canceled, and It is possible to prevent a sharp protrusion, it is possible to prevent the chuck of the electric drill device from colliding with the base material and the drill from colliding with an object on the back surface of the base material. Since the sudden protrusion prevention device is pressed against the base material to perform the drilling, the drilling can be performed in a stable state of the drill, and the through-hole can be formed at a right angle to the base material. Furthermore, if a scale plate for measuring the amount of contraction of the telescopic rod is provided, the telescopic rod is contracted by the same force as the depth of the hole due to the pressing force to the electric drill device. The length of the drill can be easily known, and the pressing force applied to the electric drill device can be weakened just before the cutting edge of the drill penetrates the base metal, and the inertia force can be suppressed. It is also effective when trying to cut a dead end hole instead of
Exerts an excellent effect.

[Brief description of the drawings]

1A and 1B show an embodiment of a drill sudden protrusion preventing device of the present invention, in which (A) is a sectional view and (B) is (A).
3A is an A-A direction arrow view, and (C) is an enlarged view of a B part in (A).

FIG. 2 is an explanatory diagram showing a usage example of the present invention.

FIG. 3 shows another embodiment of the present invention.
It is an enlarged view corresponding to (c).

FIG. 4 is a schematic diagram showing still another embodiment of the present invention.

FIG. 5 is a schematic diagram showing an application example of the present invention.

FIG. 6 is a schematic diagram showing another application example of the present invention.

FIG. 7 shows a modified example of the gripping tool which is the main part of the present invention, wherein (a) is a schematic view showing a case where the slit forming part of the gripping tool main body is a flat surface, and (b) is for tightening. It is a schematic diagram showing the case where the inner surface of a nut is made flat.

FIG. 8 is a schematic view showing a state of punching.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electric drill device 2 Chuck 3 Drill 4 Base material 7 Support plate 8 Grasping tool 11 Grasping tool body 12 Bearing 14 Telescopic rod 15, 15 'Contact plate 24 Scale plate

Claims (2)

[Claims] 1. A telescopic rod which is rotatably attached to a support plate by piercing a gripping tool for gripping a drill so that the drill can rotate integrally, and at the same time, a telescopic rod adapted to act in an extending direction. The drill is characterized in that it is mounted so as to be parallel to the above-mentioned telescopic rod, and a contact plate for applying the base material for performing drilling is fixed to the tip of the telescopic rod. Projection prevention device. 2. The sudden projection preventing device for a drill according to claim 1, wherein a scale plate for measuring the contraction amount of the telescopic rod is provided on the support plate.