SU1407688A1 - Insert grooving tool - Google Patents

Abstract

The invention relates to metalworking, namely to a precast metal cutting tool. The purpose of the invention, which is to increase the reliability of fastening the plate. When machining holes of small diameter, this is achieved due to the eccentric position of the slot under the plate relative to the center of the holder, which guarantees the greatest rigidity of the cutter due to the increased thickness of the holder under the plate's supporting plane. The prefab groove cutter consists of a holder, a cutting plate installed in the seat of the holder body, made at the end of the latter, and secured with a fixing screw. The center of the diameter of the circumference of the cutting plate is located above the center of the diameter of the holder body and is offset along the bisector of the angle at the bottom of the plate in such a way that the supporting surfaces under the plate have the largest area, which guarantees the greatest rigidity of the cutter when bore small diameter holes. The cutting plate is made of a replaceable three-edged carbide insert with rear corners and without a hole. The lateral support surfaces of the holder slot are made at an acute angle B to the longitudinal axis of the holder body, and the axis of the mounting screw is angled to the base of the socket, with more angle, which ensures the reliability of the base and mounting plate in the holder body slot. 5 il. (L

Description

Od

CX) 00

The invention relates to metal-working, namely to a metal assembly; :: cutting tool.

The purpose of the invention is to increase the gentle attachment of the plate with the formation of small diameter holes in TKe due to the eccentric position of the nest under the plate relative to the center of the tree, which guarantees the greatest tenacity of the cutter due to the increased thickness of the holder under the plate supporting plane.

FIG. shown cutter, side view; figure 2 - the same .View from above; on fng.Z - view A in fig. 1 (the cutting insert is not shown); FIG. 4 is a view A of FIG. figure 5 - section bb on phage.4.

The prefab groove cutter consists of a holder, a cutting plate 2 installed in the seat of the body of the support 1, made at the end of the latter, and secured with a fastening screw 3. The side surfaces of the holder seat are angled to the axis of the holder.

. The center (0 „) of the diameter described by the R-R: Cutting plate 2 is located according to the diameter of the body of the holder 1 and is offset along the bisectrix 4 of the angle f at the lower top 5 of the plate

by the value determined according to equality

t sin A

S.-T -.-----

sin 1

(I)

gle a

0

arc sin - l2R (R-t) - angle,

ZK.

enclosed by the melody by the horizontal axis of the diameter of the described circumference of the cutting plate and perpendicular to the chord, lowered onto the chord, deg; 20 -A ° - angle enclosed

between the bisector of the angle at the lower top of the plate and the perpendicular rom lowered: chord, hail, P1 | and the center (0 ") of the holder body p4 is located at the intersection of the aforementioned toy bisectrix 4 s perpendicular - pcJM 6, lowered from the point ), displaced along the horizontal axis 7 of the diameter of the described circumference (2R), I cut

of an alkaline plate 3. at the maximum depth of the groove to be machined in the opposite direction of the cutting 8 cutter, on the chord of 9 (BV) diameter,

15

0 5

about

five

0

five

0

The circumference of the cutting plate with the center at the specified point A connects the point B of the intersection of the horizontal axis 7 of the diameter of the circumscribed circle of the cutting plate 2 with this circle and the point at the intersection of the vertical 10 drawn from the center of the cutting plate with the same circumference (R.) Body holder 1 is made in accordance with the equality

RK. R - b,. (2) where n is the radius of the body of the toolholder

° cutter, mm;

R is the radius of the circumference of the cutting plate, mm;

b i X - 2 tXcos 60 °,

where t is the maximum depth of the groove to be machined, mm; X is the value of the displacement of the center of the diameter of the described circumference of the cutting plate relative to the center of the diameter of the body of the holder along the bisector of the angle at the lower tip of the plate, mm.

The cutting plate 2 is made of a replaceable three-sided carbide plate 11 (its dimensions are shown by a dash-dotted line) with rear corners on facets x 12 and without a central through hole. The side bearing surfaces 3 of the holder have an acute angle i to the longitudinal axis 14 of the body of the holder 1, and the axis 15 of the fixing screw 3 is located in a plane passing through the bisector 4 of the angle & enclosed between the side surfaces 13 of the holder hollow 1 and at an angle S to the base 16 of the socket, the value of which is greater than the angle of inclination of said surfaces of the socket to the axis 14 of the holder, i.e. f.

I

Fulfillment of the conditions of mathematical dependencies (1) and (2) ensures the greatest rigidity of the cutter, since with this design of the sector P and 12 sockets of the holder body have the greatest area and at the same time, the processing of grooves in holes of small diameter, starting with a diameter of 14 mm (t a little more than the diameter of the circumference of the cutting plate).

Making a cutting plate from a replaceable three-sided carbide plate with the back corners on the edges makes it possible to increase the reliability of mounting the plate by eliminating the plates tilting in the slot of the cutter when fastened with a fixing screw. The slope of the side surfaces 13 of the socket of the holder ensures reliable power closure of the plate to the base 16 of the socket, which increases the reliability of its base and fastening.

The location of the axis 15 of the fastening screw 3 in the plane passing through the bisector 4 of the angle increases the reliability of mounting the plate by uniformly distributing the clamping force of the plate on both surfaces 13 of the holder sockets, which ensures the accuracy of the plate base and eliminates its distortions.

Justification of the choice of mathematic relations.

Take the minimum diameter of the processed hole is equal to

DoBp.oTfo D + D,

where D is the diameter of the circumference of the cutting plate, mm (radius R, figure 4),

L is the minimum clearance required for inserting the cutter into the hole.

Consider in figure 4 a triangle 4 AO „В, where, from here

 4R Consider, where 0 „B R - t;

0 "At t, from here (Rt)

) J2R (R-t5.

Consider L AVG, from where

VG | l2R (R-t);

sin TAB

| -lJ2R (R-t), from where

/ -A arcsin-g 2R (r-t).

/TO

lo „

Consider L O AO, t.

where is L0

60

From the solution of oblique triangles by the sine theorem, we have sin od

Of

NIKOV

b R

solutions of oblique triangular by the cosine theorem we have

AO. 2tX cos 60

to..

from here R

. AD-AO,

 R - b.

20

Claims (1)

Invention Formula 0 A precast groove cutter with a mechanical fastening of a replaceable three-sided equilateral carbide 5 plate installed in the holder's slot, made on the end of the holder, and fixed with a fixing screw, characterized in that, in order to increase the reliability of the plate fastening when machining holes of small diameter, The bisector of one of the corners of the socket under the plate coincides with the diameter of the holder, and the center of the socket under the plate is shifted relative to the center of the holder in the direction opposite to the top of the angle of the socket under the plate slime, with lateral support surfaces vtolneny socket holder at an acute angle to the longitudinal axis derzhayki housing, and the fixing screw axis lies in a plane passing through the bisector of the angle enclosed between the lateral abutment surfaces of the holder slot and at an angle to the base of the slot. five 0 five figure 1 j1 // phage. 2 Vida Q) and2.3 1407688 viewA / 13 Yu 6-6 C) and 2A P 15