ABRADING TOOL FOR A ROTARY DRESSER

• US 20160271752A1
• Filed: 02/26/2016
• Published: 09/22/2016
• Est. Priority Date: 03/20/2015
• Status: Active Grant

• Current Assignee: Rolls-Royce PLC (Rolls-Royce Holdings Plc)
• Original Assignee: Rolls-Royce PLC (Rolls-Royce Holdings Plc)
• Inventors: NOVOVIC, Donka, BUTLER-SMITH, Paul, SPAMPINATO, Alessio, AXINTE, Dragos, DAINE, Mark
• Granted Patent: US 10,239,184 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B24B 53/053 using a rotary dressing tool
• CPC Class Codes: B24B 53/062 using rotary dressing tools B24B53/07 takes precedence
• CPC Class Codes: B24B 53/07 by means of forming tools having a shape complementary to that to be produced, e.g. blocks, profile rolls
• CPC Class Codes: B24B 53/14 Dressing tools equipped with rotary rollers or cutters; Holders therefor
• CPC Class Codes: B24D 18/0045 by stacking sheets of abrasive material
• CPC Class Codes: B24D 3/00 Physical features of abrasive bodies, or sheets, e.g. abrasive surfaces of special nature; Abrasive bodies or sheets characterised by their constituents
• CPC Class Codes: B24D 5/066 with segments mounted axially one against the other
• CPC Class Codes: B24D 5/14 Zonally-graded wheels; Composite wheels comprising different abrasives

Abstract

A roller assembly for a rotary dresser comprise a plurality of axial segments which may be in the form of discs, each disc provided with an abrasive, radially outer surface. The discs are secured in axial alignment, each in a preconfigured rotational orientation. The disc assembly has a centrally arranged aperture for receiving a rotor shaft. The abrasive surface of the assembly can be accurately presented as an array of uniformly shaped abrasive units in a predefined pattern.

Claims

1. A roller assembly for a rotary dresser comprising a plurality of discs, each disc provided with an abrasive, radially outer surface, the discs secured in axial alignment, each in a preconfigured rotational orientation and a centrally arranged aperture for receiving a rotor shaft and wherein the radially outer surface of one or more discs has been subjected to a process of material removal whereby to form a pre-defined pattern of individual abrasive units.

3. A roller assembly as claimed in claim 1 wherein the disc radially outer surface has been processed using an energy beam ablation technique to remove material from an evenly distributed layer of abrasive material whereby to provide individually formed abrasive units.

4. A roller assembly as claimed in claim 3 wherein the abrasive material is polycrystalline diamond (PCD).

5. A roller assembly as claimed in claim 1 wherein the geometry of the abrasive units is defined using at least a primary rake angle (γ

) and a primary clearance angle (α

).

6. A roller assembly as claimed in claim 5 wherein the geometry of the abrasive units is further defined using a secondary rake angle and a secondary clearance angle different from the primary rake angle (γ

) and primary clearance angle (α

).

7. A roller assembly as claimed in claim 1 wherein one or more of the discs are composed from multiple disc segments.

8. A roller assembly as claimed in claim 1 further comprising a hub received in a common bore of the disc assembly, first and second flanges arranged on opposite axially facing surfaces of the disc assembly, an arrangement of tapped holes extending through each flange and into the hub and an arrangement of fasteners securely received in the tapped holes, whereby to hold the discs, flanges and hub in axial and rotational alignment.

9. A roller assembly as claimed in claim 8 wherein one or more of the discs comprise of multiple segments which are arcuate and have an axially facing surface and a radially outer surface, and a pair of symmetrically arranged holes passing through the segment, recesses are provided in one or both of the flanges in alignment with the holes and locking pins are located in the aligned holes and recesses.

10. A roller assembly as claimed in claim 8 mounted on a rotor shaft between axially aligned spacers and rotationally and axially locked in position by means of a locking nut.

11. A roller assembly as claimed in claim 1 wherein the discs are provided in a range of diameters and are arranged in a pre-defined order to provide a pre-defined, non-linear circumferential profile of the roller assembly.

12. A roller assembly as claimed in claim 1 wherein not all the discs share the same population density of abrasive units on their radially outer surface.

13. A roller assembly as claimed in claim 1 wherein the geometry of the abrasive units is not consistent between all discs.

14. A roller assembly as claimed in claim 1 comprising a radially outer surface presenting an array of abrasive units arranged in a pre-defined pattern, wherein the pattern is configured to provide flow channels between abrasive units across the radially outer surface.

15. A disc for a roller assembly as claimed in claim 1 wherein a radially outwardly facing surface of one or more abrasive units is provided with a pattern of micro abrasive units of substantially smaller proportions than the abrasive units.

2. A roller assembly for a rotary dresser comprising at least one disc provided with an abrasive, radially outer surface which has been subjected to a process of material removal whereby to form a pre-defined pattern of individual abrasive units, the discs(s) secured in axial alignment with at least one roller portion having an arrangement of abrasive grains about its radially outer surface, the disc having a finer grained abrasive surface than the one or more roller portions.

17. A roller assembly as claimed in claim 2 wherein the disc radially outer surface has been processed using an energy beam ablation technique to remove material from an evenly distributed layer of abrasive material whereby to provide individually formed abrasive units.

18. A roller assembly as claimed in claim 2 wherein the geometry of the abrasive units is defined using at least a primary rake angle (γ

) and a primary clearance angle (α

).

19. A roller assembly as claimed in claim 18 wherein the geometry of the abrasive units is further defined using a secondary rake angle and a secondary clearance angle different from the primary rake angle (γ

) and primary clearance angle (α

).

20. A roller assembly as claimed in claim 2 wherein one or more of the discs are composed from multiple disc segments.

21. A roller assembly as claimed in claim 2 wherein the discs are provided in a range of diameters and are arranged in a pre-defined order to provide a pre-defined, non-linear circumferential profile of the roller assembly.

22. A roller assembly as claimed in claim 2 wherein not all the discs share the same population density of abrasive units on their radially outer surface.

23. A roller assembly as claimed in claim 2 comprising a radially outer surface presenting an array of abrasive units arranged in a pre-defined pattern, wherein the pattern is configured to provide flow channels between abrasive units across the radially outer surface.

24. A disc for a roller assembly as claimed in claim 2 wherein a radially outwardly facing surface of one or more abrasive units is provided with a pattern of micro abrasive units of substantially smaller proportions than the abrasive units.

16. A roller for a rotary dresser, the roller provided with an abrasive, radially outer surface onto which axial segments are defined wherein the radially outer surface of the roller has been subjected to a process of material removal whereby to form a pre-defined pattern of individual abrasive units on each defined axial segment and wherein the pre-defined pattern is different for different axially defined segments whereby to address different dressing needs and tool wear rates at different axial positions along the roller.