RU202239U1 - Twist drill - Google Patents

Abstract

The utility model relates to mechanical engineering and can be used for drilling holes in various materials. The twist drill contains a shank with notches, two feathers with ribbons formed by spiral grooves, a curved cutting edge and a transverse edge. The angle between the axis of the drill and the tangent to the profile of the cutting edge at the point of its abutment to the strip is selected from 3 ° to 20 °. The angle between the drill axis and the tangent to the profile of the cutting edge at the point of its abutment to the transverse edge is selected from 45 ° to 75 °. The notched shank contains a cemented layer that is 0.5 mm thick. The wear resistance of the shank is increased. 1 ill.

Description

Technology area

The utility model relates to mechanical engineering and can be used for drilling holes in various materials.

State of the art

Known device, twist drill (Patent RU No. 2576356 C1, IPC B23B 51/02 (2006.01), published on February 27, 2016, bull. No. 6), containing a shank, two feathers with ribbons formed by spiral grooves, cutting edges of a curved shape and transverse edge, the angle between the axis of the drill and the tangent to the profile of the cutting edge at the point of its abutment to the strip is from 3 to 20 °, and the angle between the axis of the tool and the tangent to the profile of the cutting edge at the point of its abutment to the transverse edge is from 45 to 75 °.

The disadvantage of this device is the insufficiently high coefficient of friction at the point where the drill is clamped in the chuck.

The closest in technical essence to the proposed device is (patent RU 191476 U1, IPC В23В 51/00, published 08/07/2019 Bull. No. 22) a twist drill containing a shank, two feathers with ribbons formed by spiral grooves, curved cutting edges and transverse edge.

The disadvantage of this cutting tool is the insufficient coefficient of friction at the point where the tool is clamped in the chuck.

Disclosure of a utility model

The technical result of the utility model is to increase the wear resistance of incisions with acute-angled shapes located on the drill shank.

The present technical result is achieved in a twist drill device containing a shank with notches, two feathers with ribbons formed by spiral grooves, a curved cutting edge and a transverse edge, while the angle between the drill axis and the tangent to the profile of the cutting edge at the point of its abutment to the tape is from 3 ° to 20 °, and the angle between the axis of the drill and the tangent to the profile of the cutting edge at the point of its abutment to the transverse edge is from 45 ° to 75 °, and a cementation coating is made on the notched shank, the thickness of which is 0.5 mm.

The hallmark is:

on the shank with notches, a cementation coating is made, the thickness of which is 0.5 mm, which makes it possible to increase its wear resistance, hardness and, as a consequence, increase the resource of acute-angled notches on the surface of the twist drill.

Comparison of the proposed solution with the analogue and the prototype did not reveal the signs of the proposed solution in them, this made it possible to conclude that the criterion of "novelty" was met.

Brief Description of Figures

The claimed utility model is illustrated in Fig., Which shows a frontal view of a twist drill containing 1 - shank; 2 - working part; 3 - notches in the course of cutting rotation; 4 - notches against the course of cutting rotation; 5 - cementing coating of the liner.

Implementation of the utility model

The manufacturing technology of the proposed device is similar to the manufacturing technology of the known spiral drill with acute-angled notches. Cementing a notched liner consists of immersing a part in a bath of liquid medium (molten salts) and holding it there. The salts used are metal carbonates, which must be alkaline with a low melting point. Carburizing temperature with this method is 850 ° C. The processing process is as follows:

the saline solution is poured into a special container;

parts are lowered into the liquid;

the solution is heated to an operating temperature of 850 ° C;

the workpiece is kept for a specified time, usually it does not exceed 3 hours.

Cementation in a liquid medium has a small saturated layer, which does not exceed 0.5 mm. Accordingly, the time takes up to 3 hours. Among the advantages it should be noted: the processed parts have a slight deformation, and hardening without an intermediate stage is also possible. [3]

The twist drill, according to the utility model, works as follows.

The shank 1 of the twist drill is placed in the chuck and crimped with its jaws on three sides at the place where notches 3 and 4 are applied with a key from one slot and for control from the second and third. The counter cuts 3 and 4 are covered with a hardened layer 5 on the shank 1. This layer protects the tool from corrosion and increases the wear resistance of the notches on the drill shank. [four]

Sources of information:

1. Patent for invention SU No. 859043С1, cl. B23B 51/00, publ. 08/30/1981

2. Patent for invention RU No. 2576356С1, cl. B23B 51/02, publ. 27.02.2016

3.https://yandex.ru/turbo/msmetall.ru/s/metalloobrabotka/nauglerozhivanie-stali.html

4.https: //wikimetall.ru/metalloobrabotka/tsementatsiya-stali.html.

Claims (1)

A twist drill containing a notched shank, two feathers with ribbons formed by spiral grooves, a curved cutting edge and a transverse edge, while the angle between the axis of the drill and the tangent to the profile of the cutting edge at the point of its abutment to the tape is from 3 ° to 20 ° , and the angle between the axis of the drill and the tangent to the profile of the cutting edge at the point of its abutment to the transverse edge is from 45 ° to 75 °, characterized in that the notched shank contains a coating in the form of a cemented layer, the thickness of which is 0.5 mm.

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