RU1808507C - Drill - Google Patents

Abstract

Usage: metal cutting, in particular, can be used to make holes in parts from difficult materials. SUMMARY OF THE INVENTION: The drill bit contains a feather (1,2) separated by chip grooves (3,4). On each feather, the main cutting edges (5.6) are made. The drill has a transverse edge shortened by the undercut (8.9) of the core from the side of both chip grooves (3.4). The undercut of the core (9) from the side of the chip groove (3) is made over its entire length with a constant distance from the drill axis equal to half the size of the core jumper. 4 ill.

Description

The invention relates to metal working and can be used to produce holes in parts from difficult to process materials.

The purpose of the invention is to increase the durability of drills.

The proposed design of the drill and its elements allows to increase its durability by improving the quality of sharpening and its simplification, since the presence of a grind on one of the chip grooves or an additional groove made along the entire length of the working part and the bottom of which is located at a constant distance from the drill axis, equal to half the thickness of the jumper, allows using any measuring tool to maintain the specified thickness of the jumper, undercutting in only one of the chip grooves, which echivaet and symmetrically arranged cutting edges and a transverse edge at the cutting part of the tool and the relative metal removal while reducing complexity twice at each resharpening compared to known drills

In FIG. 1 shows a General view of the working part of the drill; figure 2 is a view of figure 1; in Fig.Z - section bB of Fig.1; Fig. 4 is a section along the axis of the drill with conditionally distributed grooves.

The drill contains feathers 1 and 2, separated by chip grooves 3 and 4, Each feather 1 and 2 is equipped with a main cutting edge 5 and 6, respectively. The drill has a transverse edge 7, shortened by a groove 8, 9 of the core 10 from the side of both chip grooves 3 4 until a jumper 11 is formed with a value of b equal to 0.08-0.1 of the diameter of the drill d. The undercut 9 of the core 10 from the side of the chip groove 3 is made over its entire length with a constant distance of 0.5 b from the axis of the drill and has the shape of a groove with a profile 12 that corresponds to the profile 13 of the undercut 8 made from the side of the chip groove 4.

The manufacture, sharpening and regrinding of the drill is carried out as follows.

Chip grooves 3 and 4 are milled on a cylindrical drill stock with a core thickening 10 toward the shank. After that, the workpiece is installed horizontally and on one of the chip grooves 3 a milling cutter with an undercut profile 12 perform an additional ka-. Navka 9 along the entire length of the working part and with the same spiral pitch as that of the chip groove 3, while the distance between the bottom of the additional groove and the axis

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the drill should be equal to half the thickness of the jumper b of the finished drill. After heat treatment and round grinding, grinding and polishing of the chip grooves 3, 4 is carried out. Then, an additional groove 9 is grinded, which serves as the base grinding, and grinding is carried out with the profile of the grind 13. After that, the cutting part of the drill is sharpened on predetermined surfaces, providing a predetermined angle at its apex. Then, from the side of the chip groove 4 without the additional groove, undercut 8 of the core 10 is continuously monitored by the thickness of the jumper 11 using any measuring instrument, for example, a micrometer or vernier caliper. After reaching the set value of the jumper 11, sharpening is stopped and the drill is ready to work. Grinding of worn-out drills is carried out in the same order as sharpening of a new drill and includes grinding at specified surfaces and undercut of the jumper from the side of one chip groove,

An experimental batch of drills of the proposed design was manufactured at the Omsk branch of NIID. The diameter of the drill is 8.5 mm, the thickness of the lintel is 0.8 mm, the material of the cutting part is high-speed steel R12F2K8MZ. Drills were intended for machining part 89.04.50.048 of material KhN62VMYuT-VD.

The drills were tested in the conditions of the machining workshop of OMPO im. Baranova. Drills K6103-0459 from R12F2K8MZ high-speed steel, which are currently used in technology for processing the above parts, were tested as a base object.

The tests were carried out on a turret lathe in the following modes: rpm, 08 mm / rev, AKvol-10M cooling. Drilling depth 28 min.

Drills 722.2301.8604.000 of a new design before regrinding processed 5-6 parts, and drills K6103-0459 - no more than 2 parts. At the same time, regrinding drills of a new design cost 1.5-2 times less time than drills used by technology.

Based on the test results, it was concluded that the proposed drill design allows to increase the drill resistance by 3-4 times while increasing labor productivity by 1.3 times by reducing the number of regrind during the shift and reducing the time spent on each regrind.

The average annual consumption of the entire range of drills at OMPO them. The ram for processing holes in parts made of hard materials is 4280 pieces.

Claims (1)

SUMMARY OF THE INVENTION A drill for machining parts from difficult alloys, comprising two pens with main cutting edges formed thereon, separated by chip grooves, and a transverse cutting edge, the core having the sides of both chip grooves are sharpened and form a jumper equal to 0.08-0.1 of the diameter of the drill, characterized in that, in order to increase the durability of the drill by improving the quality during regrinding, the core is sharpened on the side of one of the chip grooves for the entire length of the last the distance from the axis of symmetry of the feathers, equal to half the thickness of the bridge, and has the shape of a profile of the undercut made from the side of the other chip groove. Buffa 6-5