ES2392530B1 - DRILL WITH DECENTRATED CUTTING AREA. - Google Patents

Abstract

Drill with offset cutting area, comprising a lower end for gripping said drill in the appropriate device, while the opposite end comprises a cutting head, where the cutting head has a cutting edge (AF) that exceeds the geometric axis (Z), so that the distance (x) is always less than the distance (y), (x) being the distance from the point (A) of the drill to the central vertical axis (Z), and where (y) is the distance from the point (D) of the drill to the central vertical axis (Z).

Description

Drill with offset cutting area

Object of the invention

The proposed invention deals with a drill with an off-center cutting area, with an asymmetric profile with respect to its central axis, these bits being mainly of fast steel, hard metal, hard metal and coating, ceramic and polycrystalline diamond.

Its use is especially intended for the composites, glass and carbon fibers industry, and sandwich is made of fiber and metal.

Background of the invention

The drilling of carbon fiber and metals such as aluminum, titanium and others, with convex tip bits causes several problems with the current bits. Such problems are, among others, heating, delamination, short life of the drill, energy consumption or defective completion of the holes.

Carbon fiber is a very poor heat conductive material that is produced in the drilling operation. Said heat is absorbed by the tool, which deteriorates geometrically, reaching the metal area of the sandwiches in very poor condition, and leaving important delaminations in the carbon fiber.

In conventional convex drill bits, heat is produced mainly at the front center point, seeing Figure 1, it would be point E, where the tangential speed is equal to zero.

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On the other hand, the core of the drill at point E is a space that, however much we reduce it, we will always have an area that does not cut, that is rubbing on the fiber and therefore, is heating the entire drill, and not Let the carbon fiber out fluently.

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Description of the invention

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The proposed invention solves in a fully satisfactory manner the problems set forth above. It is a drill with an off-center cutting area, with an asymmetrical profile with respect to its central vertical axis. Seeing Figure 1, the line of cut AF exceeds the geometric axis Z, making the point C not a space, but a point from which the drill begins to cut and not to rub. For this, the distance "x" must always be less than the distance "y".

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With this drill, a convex cone is produced in the material, ACB, which centers the drill, minimizing deviations from it on the Z axis.

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Thus, the drill of the invention provides numerous advantages over conventional drills. Among these advantages we highlight the lower energy consumption in the drilling process, as well as the lower heating of said drill. Similarly, it is noted that the drilled fiber does not produce delamination either in the entrance area, or in the exit area of the drill.

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   It is also worth noting that the drill arrives in optimal conditions, with respect to conventional systems, to metal areas in cases of carbon fiber sandwiches with aluminum or titanium, or any of these

two with carbon fiber. In addition, tolerances of ± 0.003m / m and optimal terminations can be achieved.

Description of the drawings

To complete the description that is being made and in order to help a better understanding of the characteristics of the invention, according to a preferred example of the practical realization thereof, a set of drawings is accompanied as an integral part of said description. where for illustrative and non-limiting purposes, the following has been represented:

Figure 1 shows a profile view of the top or cutting area of the drill of the invention.

Preferred Embodiment of the Invention

The invention described relates to a drill with an offset cutting zone, which comprises a lower end for gripping said drill in the appropriate device, while the opposite end comprises a cutting head. This drill can be used for various tasks such as drilling of composites such as fiberglass or carbon fiber, and sandwiches, fiber and metal type.

If Figure 1 is observed, we can see the drill bit of the invention. The central vertical geometric axis of the drill has been marked with (Z), differentiating aside the cutting point (A) that is part of the cutting edge (AF), while there is another edge (FD), where the point (D) is below (A). The distance from the point (A) of the drill to the central vertical axis (Z) has been defined as (x), while (y) is the distance from the point (D) of the drill to the central vertical axis ( Z).

The particular feature of the invention is that the cutting head has a cutting edge (AF) that exceeds the geometric axis (Z), so that the distance (x) is always less than the distance (y). Thus, when the edge (AF) exceeds the central geometric axis (Z), the point is achieved

5 (C), which is the point where the edge (AF) cuts the central geometric axis (Z), is not a mere space, but a point from which the drill begins to cut and not to rub.

With this drill a convex cone is achieved in the material that is drilled (ACB), which centers the drill, minimizing the deviations of the same in the central vertical axis (Z).

The drill will be of the type made from one of the following materials: fast steel, hard metal, hard metal and coating, ceramic or polycrystalline diamond.

Claims (2)

1.- Drill with offset cutting area, which comprises a lower end 5 for gripping said drill bit in the appropriate device, while the opposite end comprises a cutting head, characterized in that the cutting head has a cutting edge (AF) that exceeds the geometric axis (Z), so that the distance (x) is always less than the distance (y), being (x) the distance from the point (A) of the drill to the central vertical axis (Z), and 10 being (and) the distance from the point (D) of the drill to the central vertical axis (Z). 2.-Drill with offset cutting zone, according to previous claims, characterized in that the drill is of the type manufactured from one of the following 15 materials: fast steel, hard metal, hard metal and coating, ceramic or polycrystalline diamond.