Method of dressing a tool

Patent metadata

Field	Value
Publication number	US-10343256-B2
Application number	US-201615207461-A
Country	US
Kind code	B2
Filing date	Jul 11, 2016
Priority date	Jul 10, 2015
Publication date	Jul 9, 2019
Grant date	Jul 9, 2019

Abstract

The present disclosure relates to a method of dressing a tool which can be used for the gear manufacturing machining of a workpiece on a dressing machine, wherein the dressing takes place with line contact between the dresser and the tool; wherein a specific modification of the surface geometry of the tool is produced in that the position of the dresser with respect to the tool during dressing is varied in dependence on the tool width position.

First claim

The invention claimed is:

1. A method of dressing a tool, which can be used for gear tooth machining of a workpiece, on a dressing machine comprising a dresser, the method comprising:
dressing the tool with line contact between the dresser and the tool; and
producing a specific modification of a surface geometry of the tool in that a relative position of the dresser with respect to the tool is varied in dependence on a tool width position during dressing,
wherein at least two degrees of freedom of the relative position of the dresser with respect to the tool are controlled when dressing in line contact independently of one another as a function of the tool width position.

2. The method in accordance with claim 1 , wherein the specific modification of the surface geometry of the tool produced by the variation of the relative position of the dresser with respect to the tool when dressing in dependence on the tool width position can be described at least approximately in a generating pattern in a first direction as a linear, quadratic, or cubic function whose coefficients in a tool width direction are given by functions C 0FS , C 1FS , C 2FS , and/or C 3FS , and/or by coefficient functions F FtC,1 for a constant portion, F FtL,1 for a linear portion, and/or F FtQ,1 for a quadratic portion.

3. The method in accordance with claim 1 , wherein the specific modification of the surface geometry of the tool is specifiable by at least one out of:
the specific modification of the surface geometry of the tool produced by the variation of the relative position of the dresser with respect to the tool when dressing in dependence on the tool width position is specifiable as a function of the tool width position at at least three rolling angles as a function of the tool width position;
an association of a specific radius of the dresser with respect to a specific radius of the tool takes place, with the association being specifiable as a function of the tool width position;
an association of two specific radii of the dresser with two specific radii of the tool takes place, with the association being specifiable as a function of a position in a tool width direction; and
the specific modification of the surface geometry of the tool is specifiable as a function of the tool width position at at least one rolling angle as a function of the tool width position and the rolling angle at which the specific modification is specifiable is specifiable as a function of the tool width position.

4. The method in accordance with claim 3 , wherein at least one out of the following applies:
the dressing takes place on one flank and the at least two rolling angles are arranged on the one flank;
wherein the dressing takes place on two flanks and the at least two rolling angles are distributed over the two flanks; and
wherein the dressing takes place on two flanks and a tool having a conical base shape is used, with the conical base shape being used for setting the specific modification.

5. The method in accordance with claim 1 , wherein a modified dresser is used for dressing the tool, and wherein a position in which the a modification of the dresser is applied to the tool during dressing is specifiable in dependence on the tool width position and is changed by controlling axes of movement of the dressing machine during dressing.

6. The method in accordance with claim 1 , wherein the dressing takes place in at least a first stroke and a second stroke in line contact in each case, and wherein a position at which a first modification produced in the first stroke adjoins a second modification produced in the second stroke is changed in dependence on the tool width position.

7. The method in accordance with claim 6 , comprising at least one out of:
setting axes of movement of the dressing machine during dressing differently in the first and second strokes, in addition to a change required for different positioning between the dresser and the tool in the first and second strokes, in order to influence a pitch and/or a crowning of at least one out of the first and second modifications, with the pitch and/or the crowning being specifiable as a function of the tool width position;
setting at least one out of the first and second modifications such that a surface geometry produced by the first stroke adjoins a surface geometry produced by the second stroke at a desired angle and tangentially;
specifying at least one out of the first and second modifications at at least two rolling angles, with the modification being specifiable as a function of the tool width position;
associating a specific radius of the dresser with a specific radius of the tool takes place for at least one out of the first and second strokes, with the association taking place as a function of the tool width position; and
using different regions of the dresser or different dressers for the first and second strokes.

8. The method in accordance with claim 1 , wherein a modification produced by a modification of the dresser is superposed with the specific modification of the surface geometry of the tool produced by the variation of the relative position of the dresser with respect to the tool during dressing, comprising at least one out of:
specifying a desired stretching or compression of the modification of the dresser on the tool as a function of a position in a tool width direction by an association of two specific radii of the dresser with two specific radii of the tool;
simultaneously dressing a tooth head and a tooth flank using a combination dresser, and specifying a height of the tooth head as a function of the tool width position and producing the height of the tooth head by setting axes of movement of the dressing machine during dressing.

9. The method in accordance with claim 1 ,
wherein a setting is selected from a plurality of settings of axes of movement of the dressing machine which produce a same relative position between the dresser and the tool, with the setting being selected as at least one out of a setting which provides a desired relative position with a higher accuracy, a setting which requires smaller travel movements of the axes of movement of the dressing machine, a setting which avoids collisions of the dresser, of the tool, and of machine parts with one another.

10. The method in accordance with claim 1 , wherein at least three degrees of freedom are used during the variation of the relative position of the dresser with respect to the tool for producing the specific modification, with the degrees of freedom being adjustable independently of one another for producing the specific modification, wherein an axial position of the tool is used to displace a contact line of the dresser, and two, three, or four of the following four degrees of freedom are used independently of one another as a function of the axial position of the tool to influence a modification along the contact line, the four degrees of freedom being an angle of rotation of the tool, a y position of the dresser, a center distance, and an axial cross angle.

11. The method in accordance with claim 1 , wherein at least one out of the following applies:
errors in a surface geometry of the dresser are at least partly corrected by specifying corresponding correction values on a setting of axes of movement of the dressing machine;
the dresser which was configured for a tool having a first macrogeometry and/or a first desired surface geometry and is used for dressing a tool having a second macrogeometry and/or having a second desired surface geometry, with errors resulting from the configuration for the tool having the first macrogeometry and/or the first desired surface geometry

Assignees

• Liebherr Verzahntech Gmbh

Inventors

• Wuerfel Robert

Classifications

• B24B53/083 Primary

  for tools having a screw-thread profile (B24B53/081 takes precedence) · CPC title

• G05B19/40937

  concerning programming of machining or material parameters, pocket machining · CPC title

• Y02P90/265

  Cross-Sectional Technologies · mapped topic

• G05B19/186

  Generation of screw- or gearlike surfaces · CPC title

• B24B53/14

  Dressing tools equipped with rotary rollers or cutters; Holders therefor · CPC title