SU1215879A1 - Rotatable cutting bit - Google Patents

Description

The invention relates to the field of metalworking, and specifically to the high-speed machining of light metals and alloys on milling machines,

The purpose of the invention — an increase in plate durability — is achieved due to the aerodynamic chilling, which allows a substantial reduction in the temperature in the cutting zone.

Fig. 1 shows a cutting plate, top view of fig. 2, section A-A in figure 1, figure 3, section B-B in figure 1, figure 4, section B-B in figure 1. .

On the body 1 of the cutting plate, which has the form of an oblique prism and is made of ordinary alloyed structural steel, are rigidly mounted, for example by soldering, two carbide inserts 2, whose working surfaces coincide with the planes of the bases and lateral faces of the prism. The bases form the front surfaces 3, and the side faces form the rear surfaces 4 of the plate, wherein the intersection lines of the front and rear surfaces form the cutting edges 5, and the points of intersection of the cutting edges form the cutting peaks 6. The plate is provided with a through central hole 7 extending to the front surfaces 3. The axis of the hole 7 and both cutting vertices 6 lie in the common diagonal plane of the prism.

On each of the rear surfaces 4 of the plate is made of one inclined recess 8, the rear angle o; the plane of which is greater than the OS angle of inclination of the rear surface under the cutting edge 5. The notches 8 adjoin the cutting edges 5 on the side and mate with them and with the rear surfaces 4 with radius transition sections 9, and the radius of these sections is 1-1, 5 of the radius of curvature of the vertices 6 of the cutting edges (practically, the size of the radius of the sections 9 is assumed to be 1-1.5 mm). In addition, on eadia surface 4 of the housing 1 under the corresponding cutting edge 5 there are several (at least two) semi-cylindrical open grooves 10. The axes of the grooves 10 are parallel to the diagonal

: the plane of the prism and each other, and the angle of inclination of these axes. to the front surfaces is 90 -o (. The distance from the axes closest to the cutting tip 6 of the grooves 10, along the diagonal plane of the prism, is equal to the pitch between the grooves and is 1.15-1.25 feed rates per turn of the cutting tool.

At the front surface opposite to the inserts 2, 3, the grooves 10 are connected to each other by transverse channels 11 communicating with

adjacent groove 8.

The length of each cutting edge 5 corresponds to the maximum allowable depth of cut.

Swivel cutting plate

works as follows.

Before the start of the cycle, the plate is placed in the slot of the cutting tool (for example, an end mill), basing it on the two rear surfaces 4 and on one front surface 3, and then rigidly fixed with a screw that passes through the hole 7. Turning on the machine, bring the tool into rotation and

move it to the workpiece fixed on the machine table. The rotating tool plate with its cutting edge 5 cuts into the workpiece and removes the metal layer of a predetermined thickness.

During its rotation and during machining of the workpiece, the tool (milling cutter) with cutting plates simultaneously performs the functions of an axial-tangential blade swirl. Turbulent swirling airflow created by the rotation of the tool enters the inclined recesses B, which is

6 of them, the radius transitional areas 9 contribute to the further turbulence of the air jet, and through the transverse channels 11 are directed into the grooves 10, creating a constant

the air gap of the rear surface 4 and the cutting edge 5. This layer helps to prevent the formation of pins and build-up of the metal of the workpiece on the tools

due to the aerodynamic cooling of the latter.

6-5

F (/ r.2

fig.Z

Editor N. Egorova Order 933/13

Tehred M. Gergel Proofreader A.

Circulation 1000 Subscription VNIIPI USSR State Committee

for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5

Branch ShSh Patent, Uzhgorod, st. Project, 4

FIG L

Compiled by V. Zolotov

Tehred M. Gergel Proofreader A. Zimokosov

Claims (1)

i A TURNING CUTTING PLATE in the form of an oblique prism with a hole, the bases of which form the front surfaces, the side faces of the rear surfaces, and the intersection lines of the front and rear surfaces - cutting edges, characterized in that, in order to increase its resistance by aerodynamic cooling of the cutting zone, each of its rear surfaces under the corresponding cutting edge has at least two semi-cylindrical grooves communicating with each other, the axes of which are perpendicular to the cutting edge, and along one recess, boiling the back surface and the radius of the conjugate with it, the angle of inclination is greater than the relief angle of the main plate.