RU2571297C1 - Method of treatment of helical grooves with arc-like profile - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: tool in form of the body of rotation with toroidal generating flat is imposed simultaneously with three agreed movements in same plane of profiling. One of them is reciprocal-wobbling in the plane of profiling, and two others - progressive. The reciprocal-wobbling movement is performed around the centre of profile cross-section of the part, and is reversed in extreme points of the profile at end of each pass. To determine angle of wobbling movement, and to agree individual movements of the tool the definite mathematical relations are used.

EFFECT: method ensures uniform loading of the tool cutting edges with increasing of its strength.

2 dwg

Description

The invention relates to mechanical engineering and can be used for processing curved helical grooves with an arcuate profile, for example, chip grooves of metal cutting tools by milling or grinding.

The closest analogue is a method for processing complex curved surfaces [1]. The method is carried out by a rotating tool with a producing surface in the form of a torus, which is informed by three simultaneously non-linearly coordinated movements located in one profiling plane, one of which is a reciprocating, carried out around the center of the profile section of the tool’s toroidal surface, and two translational movements, ensuring that the tool touches with each profile point of the funeral surface.

The disadvantage of this method is the difficulty of compiling control programs associated with a huge number of calculations of the coordinates of control points. The technical result to which the claimed invention is directed is to reduce the complexity of compiling control programs by simplifying the tool path and increasing the manufacturability of the groove manufacturing process by using tools with different profile radii, as well as uniform cutting edge loading and increased durability.

A method for processing helical grooves of an arched profile, comprising communicating to the tool in the form of a body of revolution with a toroidal producing surface simultaneously three coordinated movements lying in one profiling plane, one of which is reciprocating in the profiling plane and two in translational, characterized in that the reciprocating the movement is carried out around the center of the profile section of the part and is reversed at the extreme points of the profile at the end of each passage, and the radius of the swinging engine zheniya equal distance from the axis of rotation of the table with the workpiece Rt to center sectional profile, and the angle ψ _max rocking movement determined by the formula:

where r is the radius of the profile section,

h is the depth of the groove,

while the translational movement of the workpiece along the axes directed perpendicular to Ds (y ₁ ) and parallel to Ds (x ₁ ); the base plane of the table agree with the reciprocating motion Dψ of the workpiece around the axis according to the formulas:

and after each pass, the workpiece is moved along the Ζ axis by the value of the line feed ΔDs (z), which is consistent with the line-wise rocking movement around the axis of the workpiece ΔΟ _ψ according to the formula:

where α is the angle of elevation of the helix of the groove,

R is the radius of the workpiece.

The proposed method allows for high-performance processing of helical grooves of an arched profile with universal tools with a toroidal producing surface, for example, milling cutters and grinding wheels using simplified software.

In FIG. 1 shows a diagram of successive movements of the workpiece during grooving in one complete pass of the tool along the profile, FIG. 2 is a diagram of relative tool movements along a profile in two sections A and B, perpendicular to the axis of the workpiece with a relatively stationary workpiece.

Processing profile f of the surface of the workpiece 1 (Fig. 1) is carried out by tool 2 in the form of a body of revolution with a toroidal producing surface. Processing is carried out on a CNC milling or grinding machine, with a vertical or horizontal axis of rotation of the spindle and with a horizontal axis of rotation of the table, with simultaneous program control in four coordinates. The tool is informed of the main movement Dr, it is brought to the workpiece using movements along the X ₁ and Y ₁ axis, so that the tool makes a radial insertion before touching the tool’s toroidal profile with the starting point A _{1 of} the machined surface profile, i.e. at the start point of the swing motion. Then the workpiece is informed of three simultaneously coordinated feed movements so that the tool sequentially touches the machined profile at points A ₂ , A ₃ , while simultaneously moving in relative motion around the center O _{0 of the} curved profile cross section of the helical surface of the tool clockwise at an angle ψ _max (Fig. 1), which is determined by the formula:

where r is the radius of the profile section,

h is the depth of the groove.

In this case, the translational movement of the workpiece along the axes directed perpendicular to Ds (y ₁ ) and parallel to Ds (x ₁ ); the basal plane of the table, agree with the reciprocating motion Dψ of the workpiece around the axis according to the formulas:

where R _t is the radius of the swinging motion, equal to the distance from the axis of rotation of the table with the workpiece to the center of the profile section.

At the extreme point of profile A ₃ (Fig. 2), the workpiece is moved by the value of the line feed ΔDs (z) along the axis of the workpiece and simultaneously rotated by an angle ΔDψ around the axis of the workpiece (point B ₃ ), which is consistent with the line feed along the axis ΔDs (z) according to the formula:

where α is the angle of elevation of the helix of the groove,

R is the radius of the workpiece.

Then, the rotational motion Οψ is reversed while continuing the coordinated feed motion Ds (x ₁ ); Ds (y ₁ ), Dψ along the profile from point B ₃ counterclockwise to point B ₁ (Fig. 2).

Thus, when the workpiece moves back and forth around the center of the profile section, the toroidal surface of the tool is always located normal to the profile of the surface being machined, while the tool works on the left or right sides of the cutting edge, which ultimately ensures uniform loading of the cutting edge and minimizes wear.

INFORMATION SOURCES

1. Pat. No. 2497636 (RF). The method of processing complex curved surfaces // S.K. Ambrosimov, M.A. Kosenkov, K.S. Ambrosimov, I.I. Kaptyushin. - Bull., November 10, 2013, No. 31.

Claims (1)

A method of processing helical grooves of an arcuate profile, comprising communicating mutual three coordinated movements to a rotating tool, made in the form of a body of revolution with a toroidal producing surface, and a table with a workpiece, the said movements being carried out simultaneously in one profiling plane and one of them is reciprocating, and two - translational, characterized in that the said movements are carried out by means of a table with a workpiece, while the oscillating movement is carried out around the center of the profile section of the workpiece and reverse at the extreme points of the profile at the end of each pass, and the radius of the swinging motion is chosen equal to the distance from the axis of rotation of the table with the workpiece R_t to the center of the profile section, and the swing angle ψ_maxdetermined by the formula:

where r is the radius of the cross section of the workpiece,
h is the depth of the groove,
while translational movements are carried out along axes directed perpendicular to Ds (y_one) and parallel to Ds (x_one) the basal plane of the table, and agree with the reciprocating motion of the workpiece D_ψ around its axis in accordance with the dependencies:

And after each pass, the workpiece is moved along the Z axis by the value of the line feed ΔDs (z), which is consistent with the line-wise swing motion around the axis of the workpiece ΔD_ψaccording to dependency :

,
where α is the angle of elevation of the helix of the groove,
R is the radius of the workpiece.

Images