JPS5815060Y2 - hole ivy - Google Patents

Description

[Detailed description of the invention] The present invention relates to an improvement of a hole cutter for drilling a large-diameter hole in the side wall of a bathtub. , a hole saw 3 that rotates around the drill 1 in parallel with the drill 1 is protruded from the support arm 2 , and a guide arm attachment part 11 that is rotatable with respect to the drill 1 is attached to the rear of the support arm 2 of the drill 1 . A plurality of holes are attached to the hole saw 3, and the base end protrudes from the guide arm attachment portion 11 in a direction substantially perpendicular to the drill 1, and the tip end is bent in a direction substantially parallel to the drill 1 on the outside of the hole saw 3. This relates to a hole cutter in which a guide arm 2 made of a spring material and having approximately the same shape as a book is attached to a guide arm attaching portion 11 approximately radially.

Conventional hole cutters do not have guide arms, so it is difficult to hold them substantially perpendicular to the wall of the hole saw, causing problems such as stopping rotation or breaking the hole saw blade.

The present invention has been devised to solve these problems of the conventional example, and its purpose is to provide a hole cutter that allows the hole saw to be easily held substantially perpendicular to a wall surface.

The present invention will be described in detail below according to examples.

A drill 1 is provided protruding from the center of a disc-shaped support arm 2, and a cylindrical hole saw 3 having a serrated tip is provided protruding parallel to the drill 1 from the peripheral edge 7 of the support arm 20.

The drill 1 is equipped with a compression coil spring 8 for buffering, and the tip of the compression coil spring 8 protrudes forward from the tip of the teeth of the hole saw 3.

A magnet 10 is embedded in the surface of the support arm 2 on the side of the cutting edge 9 of the drill 1, and the surface of the magnet 100 and the surface of the support arm 20 are flush with each other.

A chamfering blade 6 is formed which is inclined outwardly from the outer peripheral surface 5 of the base 4 of the hole saw 3 toward the support arm 2.

The chamfering blade 6 may be serrated teeth formed in the same direction as the serrations of the hole saw 3, or may be a file-like tooth.

A guide arm attachment part 11 is rotatably inserted into the drill 1 from the rear end side, and four L-shaped guide arms 12 project radially from the guide arm attachment part 11. is parallel to the direction of the cutting edge 9 of the drill 1, and the hole saw 3
It is almost flush with the tip of.

This guide arm 12 is made of an elastically flexible spring material.

Then, the drill 1 for the hole cutter is applied to a predetermined location on the wall surface or the side wall of a bathtub such as an enameled bathtub, and the drill 1 is rotated to drill a small hole.

At this time, before the hole saw 3 hits the wall, the buffer spring 8
comes into elastic contact with the wall surface, preventing the hole saw 3 from hitting the wall surface with impact.

When a small hole is drilled in the side surface with a drill 1, the hole saw 3 rotates around the drill 1 inserted into the small hole, thereby drilling a large through hole in the wall surface.

In this case, the tip of the guide arm 12 contacts the wall surface at the same time as the hole saw 3 cuts the wall surface, and as the hole saw 3 cuts the wall surface, the guide arm 12 bends and retreats backward.

During cutting, the guide arm 12 contacts the wall surface and does not rotate.

If the tips of the four guide arms 12 are in accurate contact with the wall surface during this cutting, it means that the hole saw 3 is also in contact with the wall surface perpendicularly, and conversely, some of the guide arms 12
If the tips of the holes are not in contact with each other, this indicates that the hole saw 3 is inclined with respect to the wall surface.

When the hole saw 3 finishes drilling a large diameter through hole 13 in the wall surface, the chamfering blade 6 provided on the outer peripheral surface 5 side of the base 4 of the hole saw 3 cuts the peripheral corner of the through hole 13 and chamfers it. .

The cut-out wall surface is pushed toward the cutting edge 9 of the drill 1 by the compression coil spring 8 of the drill 1 as shown in FIG. 4, making it easy to remove.

The present invention is constructed as described above, in which a rotatable guide arm attachment part is attached to the rear of the support arm of the drill, and an abbreviated spring material is attached to the guide arm attachment part. Since the guide arms are attached radially, when the hole saw cuts the wall surface, the tip of the guide arm contacts the wall surface, and as the hole saw cuts the wall surface, the guide arm bends and retreats backward. Therefore, during cutting work, the hole saw can be held almost perpendicularly to the wall surface by the guide arm, and the hole saw will not stop rotating or the blade will break, allowing the hole saw to work smoothly. Moreover, since the guide arm is made of a spring material, the guide arm itself can flex and retreat, and there is no need to use an extra spring to bias the guide arm against the wall surface. The number of parts can be reduced, and since multiple guide arms are provided radially, the guide arms can be used to guide the machine stably, and the state of cutting by the hole saw can be visually observed from the outside, making it smooth and easy to use. It has the advantage of being able to cut accurately.

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram of the conventional example after cutting, Fig. 2 is a schematic vertical sectional view of an embodiment of the present invention, Fig. 3 is a perspective view of the same, and Fig. 4 is an explanatory diagram of the same after cutting is completed. , Fig. 5 is an explanatory diagram when the above hole saw is not in accurate contact with the wall surface, Fig. 6 is a longitudinal cross-sectional view of the through hole after chamfering, 1 is a drill, 2 is a support arm, 3 is a hole saw, 4 5 is a base, 5 is an outer circumferential surface, and 6 is a chamfering blade.

Claims (1)

[Scope of utility model registration request] A support arm protrudes almost perpendicularly from the drill, a hole saw that rotates around the drill parallel to the drill is protruded from the support arm, and a guide arm mounting part that can freely rotate with respect to the drill is placed behind the support arm of the drill. Attach the guide arm, and from this guide arm attachment part, there are a plurality of substantially identical shaped pieces whose base ends protrude in a direction substantially perpendicular to the drill, and whose tip parts are bent in a direction substantially parallel to the drill on the outside of the hole saw. A hole cutter consisting of a guide arm made of spring material attached to the guide arm attachment part in a substantially radial manner.