SU1634372A1 - Rotary cutter - Google Patents

Abstract

The invention relates to dimensional machining of metals into a quotient and cutting tools. The chain of the invention is to improve the quality of the machining surface by improving chip breaking. The circular plate, installed rotatably, has a front surface in the form of a sinusoidal helicoid that intersects with a conical back surface cutting edge in the form of a circle lying in a plane parallel to the base plane. This mutual arrangement of the cutting edge and the front overhnosti provides chip control without varying the cutting depth and kmnemz cally adjustable angle, as during the cutting process, the contact of the cutting edge is made in the same plane, and during rotation, the curvilinear front surface smoothly changes the front angle of 7 slugs.

Description

The invention relates to the field of dimensional metal cutting by cutting in particular to a cutting tool.

The aim of the invention is to improve the quality of the treated surface by improving chip breaking.

FIG. 1 shows the shape of the front surface of the cutter in FIG. 2 — the proposed cutter (section along the axis of rotation of a circular plate); in fig. 3 is a design diagram for deriving an expression describing the shape of the front surface; in fig. 4 shows a circular cutting disc of the proposed cutter; in FIG. 5 is a section A-A in FIG. 4; FIG. 6 is a top view in FIG. four; in fig. 7 - sweep profile of the front surface along the radius of

The cutter includes a housing 1 mounted thereon on an axis 2 and bearings 3 a circular cutting plate 4 and a gear 5 fixed by nuts 6 The plate has a cutting edge 7 made in the form of a circle located in a plane parallel to the plane of its base 8. The back surface 9 is sharpened tapered at an angle a, the shape of the front surface 10 is a sinusoidal heticoid and can be described by the following expression

Z Z0

(tg ymax (sin y - 1) - tg ymin (sin (/) f 1))

The specified expression can be obtained as follows.

FIG. 3 shows a design diagram for outputting an expression.

316343724

Let point A belong to the cutting + 2 Rt (r - R); the edge, and the point B is on the same generator with the point A, at a distance r from the axis. / -j- 2 2

Then point A will move along - (R + r (r-R) f;

a circle of radius R located in 5 / g g

a plane parallel to the base-x plane X H - Y - R

neither, and point B will make double-R

the movement is around a circle of radius r and we set the value of r to a parametric vertical movement with an amplitude Sco, the expression of the Z coordinate and, taking into account, according to the sine law. And for one revolution 10 that in cylindrical coordinates

one oscillation is made. ,

We have: point A with coordinates X 4- Y p, we get

(R cos f, R sin p, Z0)

point B with coordinates Z Z0 + (Z, + С slny - Z0).

(rcosy, rslnp, zi + C slny), 15vr r-R

where Z0 is the coordinate of any point lying on the cutting edge; Know that the amplitude of oscillations

 Zi - the coordinate of the point of the center of oscillations; Q tg Angles - tg ymin (p r ×

(f is the angle of rotation of the generat

axis X.i

Then, in the vector form, we obtain the following expression for describing the considered-Zi Z0 - (tg ymax (R-g) -C) surface of yours:

p pd + (PB-HA) f, 25 we obtain the expressions for the above-mentioned parameter, in cylindrical coordinates

P is the radius vector of any point of the generator; Z Z0 + (Z0 -tgXmax (R-r) +

RA and PB - radius vector of points A and B.

In parametric form, 30tg ymax - tg ymin f a r 7 will be written,

X XA + (XB-XA) g; 2C “P A, +

Y - YA + (YB-YA) t;

Z ZA + (ZB-ZA) r; tg ymax - tg (.R -.

.,. . -. ..L (K-D) SIM (Y-g- r

X. Y, Z - the coordinate of any point of turn-I g K -r

. where X, Y, Z is the coordinate of any point on the surface; .

HD, YA, ZA - the coordinates of point A turn

KHNOSHT8; YB, ZB - coordinates of the point В pover-Z Z ° + tg У ™ 9 ln Sln

XNOSTI.

Substituted the coordinates of points A and B; 40

we get: - (tg ymax + tg ymin)

X R cozy) 4- (r cozy - R cozy) g, Y R + (r slny) - R slnyj) g, or

(2, + Csln -Z0) r..axCsin -l) To eliminate the parameter r, we raise I

squared expressions for X and for Y and fold them:

-tgymm (slny + 1).

X2 4- Y2 R2 cos2 p 4- R2 sin2 y + cn l

au The resulting expression allows one to determine -, o, the coordinates of any point of the front surface of r2 cos2 p (r - R f + m 2 sin 2 p (r - R) 2+ surface.

Before processing the cutter mouth -2 (R t (g - R) cos2 p 4 is poured so that the plane in which

55 is the circumference of the cutting edge, pass, P, g. П2 / л f r - R) of a piece through an axis of the processed preparation.

In this case, the butts 2, 2 /, forcibly rotate through the ax X + Y - R + r (r-R) + stubble 5, can be applied to the cutter plate.

self-rotation of the cutting plate, in this case, the cutter is set so that the plane in which the cutting edge lies lies at an angle I to the axis of rotation of the workpiece.

During processing, as the cutting blade rotates, a smooth change in the rake angle from + y at point 12 to -y at point 11 will occur, which will cause chip splitting due to changes in shrinkage and type of chips. The position of the cutting edge relative to the axis of the workpiece remains constant. The kinematic clearance angle and the depth of cut do not change and the quality of the machined surface increases.

For example, there is a cutter with forced rotation of a circular plate with a radius of R 15 mm, set so that the plane in which the cutting edge lies lies through the axis of the part. The back surface of the plate is sharpened on a cone with an angle of 6 °. Front corners

Angles -Xmin 10 °.

Then the expression for the front surface takes the form

Z Z0 + (R - / e) tg ymax sirup;

"I-Tr Ј - RV

Determine the magnitude of the front corners and the coordinates of points lying on a radius of 10 mm for angles, 90 °, 180 °, 270 ° (see Fig. 7) and 0 °

an - Zo-Zo ° Z0 - (Z0 + (15-10) tg 10 ° sinO °); ai4 0;

tgyn o: yn o °.

aii Z0-Z90 ° Z0 - (Z0 + (15 -10) tg10 ° x

X sin 90 °); an -0.88;

ЦУ а15-810 - ° -176: У11 -Ю °

ai3 Z0- Z 180 ° Z0 - (Z0 + (15-1 0) tg10 ° X X sin 180 °);

an 0:

tgyi3 1S ° 10 o,

Z0- (Zo + (15-10) tg 10 ° x

0

tgyi2 15 ° J810 0.176; y, 2-10 °.

Claims (1)

The use of a cutter with a curved front surface, made in the form of a sinusoidal helicoid, forming a cutting edge in the form of a circle lying in a plane parallel to the base plane of the circular plate in the intersection with the conical back surface, makes it possible to improve the quality of the treated surface. use of the cutter for finishing. And the limit of the change of the front corners is significantly widened compared to the cutter with a wavy cutting edge, this allows for improved chip breaking and expands the range of materials to be processed. Claims of the invention A rotary cutter comprising a body and a rotatable cutting plate with a curvilinear front surface mounted for rotation, characterized in that, in order to improve the quality of the machined surface by improving chip breaking, the curvilinear front surface is shaped as a sinusoidal helicoid ratio five 35 Z Z0 + (tg umax (siny + 1) 0 0 - tg umin (siny + 1), where Z is the coordinate of any point on the front surface; Zo - the coordinate of any point lying on the cutting edge; R is the radius of the circumference of the cutting edge; p is the length of the radius vector of any point on the front surface; Umax and Umi - the largest and smallest values of the rake angle; "P is the polar angle of the radius vector of any thin front surface, and the leading angle at any point of the cutting edge is determined from the ratio Zo -Z y arctg- -. five ZiCfrCQl  y 74 P  y3 / eight Fy -r r Phie 5 Fig 6 UGG Fiat