Claims
- 1. An abrasive system comprising a backup pad and supported thereon a fiberbacked abrasive disc the disc and pad having a common axis of rotation, wherein the backup pad has the shape of a circular disc from the periphery of which, at spaced intervals, from three to six segments have been removed, and the relative dimensions of the abrasive disc and the backup pad are such that the backup pad has a maximum radius that is from 95 to 100% of the maximum radius of the abrasive disc and, in the area of the removed segments, the abrasive disc overlaps the backup pad, and the greatest extent of said overlap is an amount that is from 10 to 20% of the maximum radius of the abrasive disc.
- 2. An abrasive system according to claim 1, wherein:
- a) the disc has from 3 to 9 viewing apertures in the body of the disc at spaced locations around at least one circle concentric with the disc and with a radius smaller than the radius of the disc; and
- b) the backup pad has from 3 to 9 viewing apertures and the disc and backup pad are aligned with the viewing apertures on both in register.
- 3. An abrasive system according to claim 2, wherein the disc has from three to six spaced portions removed from the circumference of the disc each removed portion having leading and trailing edges defined with respect to the intended preferred direction of rotation of the disc when in use, and each such removed portion has a length defined by the circumferential distance between the points at which the leading and trailing edges meet the circumference, and wherein the shortest radial dimension of the disc occurs adjacent the leading edge.
- 4. An abrasive system according to claim 3 wherein the leading and trailing edges of each removed portion on the disc meet the nominal circumference asymptotically.
- 5. An abrasive system according to claim 1 in which the number of portions removed from the circumference of the backup pad is three.
- 6. An abrasive system according to claim 2 in which the disc and backup pad are each provided with viewing apertures that are in register when the system is in use and which, in the backup pad, are located between the portions removed from the circumference.
- 7. An abrasive system according to claim 2 in which the viewing apertures are located so as to provide that, in use, the combined effect of the viewing apertures and the removed portions from the circumference is to permit continuous vision through at least half of the greatest radial dimension of the disc.
- 8. An abrasive system according to claim 2 in which the backup pad and the disc are provided with alignment means by which a disc can be mounted on the pad such that the viewing apertures in each are in register.
- 9. An abrasive system according to claim 8 in which the alignment means comprises identical, non-circular, axially located mounting holes.
Parent Case Info
This is a Continuation-in-part of Ser. No. 09/212,713, filed on Dec. 16, 1998 U.S. Pat. No. 6,077,156.
US Referenced Citations (5)
Foreign Referenced Citations (1)
Number |
Date |
Country |
2207626 |
Feb 1989 |
GBX |
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
212713 |
Dec 1998 |
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