METHOD FOR THE PRODUCTION OF A DRESSING TOOL FOR A GRINDING TOOL

Abstract

A method for the dressing of a multi-thread grinding worm by a dressing roll, wherein the grinding worm has at least two screw channels which are arranged parallel to another, which screw channels extend helically around an axis of the grinding worm and wherein the dressing roll has at least two adjacent dressing profiles which are arranged along an axis of the dressing roll, wherein the dressing profiles of the dressing roll are guided simultaneously through adjacent screw channels of the grinding worm during the dressing of the grinding worm. To improve the precision of the dressing the method includes the steps: a) execution of a first partial dressing process at which the dressing profiles of the dressing roll are guided simultaneously through first adjacent screw channels of the grinding worm; b) execution of at least one second partial dressing process at which the dressing profiles of the dressing roll are guided simultaneously through second adjacent screw channels of the grinding worm, wherein the second adjacent screw channels are, compared with step a), offset in the direction of the axis of the grinding worm by at least one screw channel of the grinding worm.

Claims

1. A method for the production of a dressing tool for a grinding tool, preferably for a grinding worm, wherein the dressing tool comprises at least one, preferably ring-shaped designed projection which extends radially, wherein the method comprises the steps: a) production of a shaped ring, which comprises a number of recesses at a radial inner area which number corresponds to the number of projections and which recesses are designed congruent to the projections; b) placing of abrasive material, especially of diamond powder, in the recesses; c) creation of a chemical or electro-chemical coating in the recesses so that the abrasive material is fixed in the region of the surface of the recesses; d) removal of the shaped ring, to obtain the so arose dressing tool; wherein a support element is placed prior or during step b) or prior or during step c) in the region of the radial inner area which support element is material joined integrally during step c) at least partially with the arising dressing tool by the coating.

2. The method according to claim 1, wherein as support element an open lattice structure with openings is used so that especially the radial inner area is not radially closed by the support element.

3. The method according to claim 1, wherein the support element extends along a width which corresponds between 90% and 100% of the width of the dressing tool.

4. The method according to claim 1, wherein as support element a structure is used which comprises a plurality of rings which run in circumferential direction of the radial inner area, wherein the rings are connected by means of cross-beams, wherein the cross-beams run in axial direction of the dressing tool.

5. The method according to claim 4, wherein the rings and/or the cross-beams consist of metal.

6. The method according to claim 4, wherein the rings and/or the cross-beams comprise a circular cross section.

7. The method according to claim 4, wherein the number of rings is the number of projections plus one.

8. The method according to claim 4, wherein the rings and the cross-beams are connected with another by material bonding, especially by welding or by soldering.

9. The method according to claim 1, wherein the shaped ring rotates around its axis at least temporary during the execution of step c).

10. The method according to claim 1, wherein the removal of the shaped ring according to step d) takes place by machining of the shaped ring, especially by turning.

Description

BRIEF DESCRIPTION OF THE DRAWING

[0031] In the drawing:

[0032] FIG. 1 shows the side view in partial radial cross section of a dressing tool being a three-groove full-profile roll,

[0033] FIG. 2 shows the radial cross section of a shaped ring with the dressing tool which is produced by means of the same and

[0034] FIG. 3 shows the perspective depiction of a part of a support element which is embedded in the dressing tool.

DETAILED DESCRIPTION OF THE INVENTION

[0035] In FIG. 1 a dressing tool 1 being a dressing roll is shown. The dressing tool 1 consists of a rotationally symmetric part which comprises a direction of the axis a as well as a radial direction r. The dressing tool 1 has a width B in axial direction.

[0036] In the embodiment the dressing tool 1 has three ring-shaped projections 2 which run in circumferential direction and which extend in radial direction r. Those projections 2 are provided with abrasive material 6 in the form of diamond powder (with corresponding grain size; dependent from the grinding tool to be dressed) so that with the dressing tool 1 a grinding worm can be dressed. This process is known as such and needs not to be explained here in detail.

[0037] The production of such a dressing tool 1 is depicted in FIG. 2. Central element for the production is a shaped ring 3 which has a substantial hollow-cylindrical shape. At a radial inner area 4 of the shaped ring 3 recesses 5 are machined (i. e. ground with high precision) which are congruent with the projections 2 (negative method).

[0038] At first, in the recesses 5 abrasive material 6 (diamond powder) is placed at the production of the dressing tool 1 so that the surface 8 of the recesses 5 is at least partially covered or faced with the abrasive material 6.

[0039] Subsequently the creation of a galvanic coating 7 takes place so that the abrasive material 6 is fixed at the surface 8 of the recess 5 and is available for the later dressing process. In FIG. 2 a situation is depicted at which the galvanic coating process is already substantially completed, i. e. the region of the recesses 5 is already filled with the material of the coating and furthermore has reached a region which extends radial inwards.

[0040] It is essentially that prior to the production of the complete coating 7 a support element 9 is introduced in the shaped ring 3 which is at least partially integrated into the forming dressing tool 1 by the galvanic coating process. In FIG. 2 it can be seen that the support element 9 was integrated completely into the coating material, i. e. it is surrounded by the same. So, the support element is connected material joined with the arising dressing tool 1. But it is also possible that after the termination of the coating process the supporting element 9 is not completely surrounded by the coating material.

[0041] After the status is reached as depicted in FIG. 2 the shaped ring 3 is removed which can be take place by a machining process. So the dressing tool 1 is available for its intended use.

[0042] In FIG. 3 the employed support element 9 is shown again in perspective view. Here, it can be seen that the support element 9 has a width b which corresponds substantially to the width of the dressing tool 1 or is marginally smaller than the mentioned width B.

[0043] The support element 9 consists of several (in the embodiment: of four) rings 11 which are connected (especially by soldering) by cross-beams 12 with another which are equidistantly distributed around the circumference. Preferably 20 to 80 cross-beams 12 are arranged around the circumference. As can be seen in FIG. 3, a result are openings 10 which allow that during the coating process electrolyte can penetrate through the support element 9 and thus the electroplating process is not or barely hindered by the support element 9.

[0044] Thus, in the present embodiment the support element (respectively support lattice) is designed as lattice structure made of longitudinal and transversal rods which structure is tensed in the shaped ring. The dimensions of the lattice structure are adapted to the contour which has to be supported. The support element is thereby so positioned in the shaped ring that the total width of the grooves (recesses) is covered and the support element is completely embedded into the nickel layer.

[0045] It should be mentioned that the coating process, which is carried out normally as an electroplating process, takes place beneficially in two steps:

[0046] In a first step the abrasive material 6 which is located in the recesses 5 is fixed by a first coating with nickel in a first working station, wherein the shaped ring rotates so that the abrasive material 6 is held by the centrifugal force in the region of the surface 8 of the recesses 5.

[0047] When the abrasive material 6 is then fixed so far then the coating 7 can be carried out in the finally desired range in a second working station. However, before this takes place the support element is introduced in the shaped ring 3 and is material joined embedded by the coating process.

[0048] While specific embodiments of the invention have been shown and described in detail to illustrate the inventive principles, it will be understood that the invention may be embodied otherwise without departing from such principles.