| 摘要 |
An abrasive disc includes a rotatable sheet. Abrasive particles are disposed on a first side of the sheet to provide an abrasive action. Coupled to the sheet means are (1) a first portion defining at least one internal thread in spaced relationship to the opposite surface of the sheet for threaded coupling with an externally threaded mandrel, (2) a second portion extending from the first portion along the opposite surface of the sheet and providing a transmittal of force from the first portion and (3) a third portion extending from the second portion into coupled relationship with the sheet and receiving the transmitted force and providing a force for driving the sheet means. The first portion of the coupling defines a boss disposed on the opposite surface of the sheet in spaced relationship to the sheet and having an opening operative as a single-turn internal thread. The second portion of the coupling defines a flange disposed against the opposite surface of the sheet in a frictional, but non-adhering, relationship with the sheet. The third portion extends from the periphery of the second portion and defines drive fingers which extend through the sheet to retain the sheet in a driven relationship. The third portion of the coupling is bent against the abrasive surface of the sheet means. When thus bent, the third portion of the coupling means is disposed in flush relationship with the sheet means because there are no burrs produced on the sheet means when the drive fingers are driven through the sheet means. |
