SU1255321A1 - Hobbing cutter - Google Patents

Description

The invention relates to metal cutting and concerns a tool for finishing teeth on cylindrical wheels, preferably a module of high hardness material.

The purpose of the invention is to increase the processing accuracy.

FIG. 1 shows a red screw cutter, general view; in fig. 2 is a view A of FIG. 1 {in FIG. 3 is a view of B in FIG. one.

Cherv Chna cutter has three teeth 1-3.

The central tooth 2 has straight lateral cutting edges 4, which are located in one plane parallel to the mill axis 0-0,

The cutting edges 5 and 6 of the outer teeth 1 and 3 are displaced from the cutting edges 4 of the central tooth 2 and are located from the axis of the cutter at a distance determined from the ratios

Ci Rjsintf

tgcicosV + 2 sincf tgo

where the angle between the cutting edge and the plane, perpendicular to the axis of the cutter; 06 - angle profile of the original profile

in: - cutter module; WITH; - distance from edge to

axis cutters;

i is the order number of the edge (equal to 3 for the two extreme edges, equal to 1 for the subsequent edges in the direction of the middle of the cutter and equal to 2 for the two edges of the middle tooth of the cutter);

255321

cf - the projection of the angle between the radius to the point of intersection of the cutting edge c. a cylindrical surface of radius Rj and a cutting edge on the 5th plane perpendicular to the mill axis;

R; - the radius of the concentric axis of the mill cylindrical surface.

The cutting edges 4-6, right and left, shape one side of the tooth. Moreover, the edges of the 6 profiled area at the legs of the wheel teeth, the edges 4 - in the middle part of the tooth, the red head 5 - at the head of the tooth.

When making a cutter according to the proposed design, one side of the tooth profiling the cutting edges in the course of processing describe surfaces that touch the theoretical tooth surface at three points located on the tooth lines passing one through the constant chord of the tooth cavity, and the others on the adjacent teeth x at the pitch distance. The sections of the tooth profile between these points form lines that have a curvature close to the curvature of the tooth profile. The magnitude of the profile error in this case is much smaller than in the case of each side being profiled with one straight cutting edge. The condition of finding the cutting edge of the nL plane passing through the tangent to the helical surface of radius RJ in increments of ii and the direct source producing contour with the main angle of profile ci is expressed by the dependence

tg p („tgotcostf + 2 sin (.

№5

F f

fig.Z

Compiled In Slitkova Editor I.Nikolaychuk Tehred .L.Serdyukov Corrector I.Musk

Order 5147. Circulation 1001 Subscription

VNIIPI USSR State Committee

Inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab, 4/5

Production and printing company, Uzhgorod, Projecto st., 4

bidb

Claims (1)

WORM MILL, made in the form of three teeth, the central one of which has a straight lateral cutting edge, characterized in that, in order to improve accuracy, the cutting edges of the extreme teeth are offset relative to the plane of the cutting edges of the central tooth by distance C; from the relation With j = R; -sin φ _; where R · is the radius of the concentric axis of the cutter of the cylindrical surface; - the projection of the angle between the radius to the point of intersection of the cutting edge with a cylindrical surface of radius R ;, and the cutting edge on a plane perpendicular to the axis of the cutter.