RU2724238C1 - End cutter - Google Patents

Abstract

FIELD: machine building.SUBSTANCE: invention relates to machine building and can be used in milling hard-to-machine metals and other materials. Cutter comprises a shank and a cutting part with screw teeth separated by grooves for chip removal .Surface of the shank in the point of clamping of the cutter in the cartridge has notches in the form of acute-angled figures. Surface area of notches is made with hardness equal to surface hardness of jaws of clamping cartridge.EFFECT: increasing friction coefficient of mill shank during machining.1 cl, 1 dwg

Description

The field of technology.

The invention relates to mechanical engineering, and can be used when milling difficult-to-process metals and other materials.

The prior art.

A device end mill is known (patent SU 1565614, IPC B23C 5/10, Published May 23, 1990), comprising a shank and a working part with helical cutting teeth and sawtooth asymmetric protrusions located on the cylindrical part of the mill.

The disadvantage of this cutting tool is the insufficient coefficient of friction at the clamping point of the tool.

A device end mill is known (patent RU 2147492 C1, IPC В23С 5/10, Published on 04/20/2000 Bull. No. 11), including a shank and a working part having helical cutting teeth with sawtooth protrusions with rounded vertices on the front surface located on the cylindrical part milling cutters asymmetrically, the radius of rounding of the vertices of said sawtooth protrusions is determined from the expression:

where S is the feed per tooth, mm / tooth;

H is the required height of the roughness, microns;

R is the radius of the rounding of the sawtooth protrusion, mm

The disadvantage of this cutting tool is the insufficient coefficient of friction at the clamping point of the tool.

The closest in technical essence to the proposed device is (patent RU 145350 U1, IPC В23С 5/10, published March 27, 2014 Bull. No. 26), an end mill containing a shank and a cutting part with helical teeth separated by grooves for chip flow, moreover the cutting part is made with an end face consisting of an undercut, a flat section located perpendicular to the axis of rotation, and a curved section formed by two conjugated sections of circles from the condition R ₁ <R _fr ≤R _2,

where R ₁ is the radius of the section of a circle associated with the cutting part and a section with a radius of R ₂ ;

R ₂ is the radius of the section of a circle associated with a flat section of the end face of the cutting part;

R _FR - the radius of the shank of the cutter.

The disadvantage of this cutter is not enough high coefficient of friction at the clamping point of the cutter.

Disclosure of the invention.

The technical result of the invention is to increase the coefficient of friction of the shank of the cutter.

The present technical result is achieved in an end mill device comprising a shank and a cutting part with helical teeth separated by grooves for chip evacuation, moreover, notches are made on the surface of the shank at the place of the cutter clamp in the chuck, creating sharp-angled figures, the surface area of the notches is made with a hardness equal to the surface hardness chuck jaws.

Distinctive features are:

notches are made on the surface of the shank at the clamping point of the cutter in the chuck by creating acute-angled figures, this technical result is achieved due to the effect of jamming the metal with notches forming angles on the surface of the shank of the cutter with the chuck metal, thereby increasing adhesion;

the surface area of the notches is performed with a hardness equal to the surface hardness of the jaws of the chuck, which increases the coefficient of friction and ensures uniform transmission of torque.

Comparison of the proposed solutions with analogues and prototype did not allow to identify in them the signs that distinguish the claimed solution, which allows us to conclude that the criterion of "novelty".

Description of the figure.

The claimed invention is illustrated in the figure, which shows a front view of the end mill, containing the shank 1, the working part 2, notches along the rotation of cutting 3, notches against the rotation of cutting 4.

The manufacture and operation of the device.

The manufacturing technology of the proposed device is similar to the manufacturing technology of the known end mill. The notches are applied to the cylindrical shank with a special cutter on a lathe in one and the other direction with the same speed of advancement of the cutter along the cutter shank, from left to right, and from right to left.

The application of notches on the tapered shank is performed with a special tool on a machine with numerical control in one and the other direction.

After applying the notches on the same machines, a shank with notches is calibrated, which corresponds to the quality of processing the shank without notches, to eliminate the imbalance caused by applying notches.

The surface area of the notches is heat-treated with a hardness equal to the surface hardness of the jaws of the cartridge using high-frequency generators performing high-speed heating by high-frequency currents (up to 40 kHz) of the surface area of the notches, followed by quenching in a bath with water.

The end mill, according to the invention, works as follows.

The cylindrical shank of the 1 end milling cutter is placed in the chuck and crimped on its three sides with jaws at the place of applying the notches with a key from one socket and for control from the second and third. Counter notches on the shank 1, deposited at an angle of 40 ° ^to 50 ° to the longitudinal axis of the cutter, provide wedging the cutter in the metal chuck jaws on the surface by creating a large number of acute-angled shank shapes capable of repeatedly increasing the coefficient of friction of the shank cutter.

It is recommended to apply notches with angles from 40 ^° to 45 ^° on small diameters of milling shanks from 6 to 20 mm. On the shanks of cutters with a large load torque it is recommended to apply a sipe angles from ^{40 ° to} 50 ° having high density cuts per unit area of the shank.

The taper shank of the end mill works similarly to a cylindrical shank.

Sources of information:

1. Patent SU 1565614, IPC B23C 5/10, Published May 23, 1990;

2. Patent RU 2147492 C1, IPC В23С 5/10, Published on 04/20/2000, Bull. No. 11;

3. Patent RU 145350 U1, IPC В23С 5/10, Published March 27, 2014, Bull. Number 26.

Claims (1)

An end mill comprising a shank and a cutting part with helical teeth separated by grooves for chip evacuation, characterized in that notches in the form of acute-angled figures are made on the surface of the shank at the clamp end of the cutter, while the surface area of the notches is made with a hardness equal to the surface hardness chuck jaws.

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