Method for dressing a multi-thread grinding worm with a multi-groove dressing roll and method for grinding a gear using a multi-thread grinding worm

A method for dressing a multi-thread grinding worm with a multi-groove dressing roll,

• wherein the grinding worm has a plurality of worm threads which run parallel to one another around a tool axis,
• wherein the dressing roll has a number of dressing surfaces which are arranged adjacent to one another along a dressing tool axis and which are tooth-shaped in radial section,
• whereby, for dressing the grinding worm, the dressing roll is brought into engagement with the worm threads,
• wherein at least two of the dressing surfaces are unevenly spaced from each other along the dressing tool axis of the dressing roll and/or at least two of the dressing surfaces differ from each other in shape in radial section,
• wherein dressing the grinding worm with the dressing roll comprises the steps of:
• a) Determination or measurement of the outer diameter of both the grinding worm and the dressing roll;
• b) With stationary grinding worm:
• b1) Radial insertion of the dressing surfaces of the dressing roll into the worm threads in a first axial relative position between the tool axis and the dressing tool axis, wherein the insertion is carried out in such a way that the dressing surfaces extend into a range between 10 % and 90 % of the height of the worm threads;
• b1a) Determination of a first axial relative position between the grinding worm and the dressing roll when a dressing surface makes contact with a first flank of the grinding worm in a worm thread;
• b1b) Determination of a second axial relative position between the grinding worm and the dressing roll when a dressing surface comes into contact with a second flank of the grinding worm opposite the first flank in a worm thread;
• b1c) Determination of an axial center position between the first and second axial relative positions according to steps b1a) and b1b);
• b1d) Positioning of the dressing roll relative to the grinding worm in the determined axial center position of the worm thread and further radial insertion of the dressing roll into the worm threads until contact between a dressing surface and the grinding worm is detected;
• b1e) Storing the radial position between the dressing roll and the grinding worm determined in accordance with step b1d) when contact is made in accordance with step b1d);
• b2) Repeating step b1) by radial insertion the dressing roll into further worm threads, wherein the insertion in the direction of the tool axis is offset by one worm thread, wherein the number of repetitions corresponds to the number of dressing surfaces minus 1;
• and
• c) Dressing the grinding worm with the dressing roll, wherein the dressing roll is moved into the relative axial center position between the grinding worm and the dressing roll in accordance with step b1c), at which the deepest radial position between the grinding worm and the dressing roll has been obtained in accordance with step b1e).