| 摘要 |
A mounting assembly for mounting precious stones such as gem blanks in a cutting and/or polishing machine comprising a self-clamping type chuck in an adjustable threaded engagement with a first inner detent ring provided with divisions for interstices and semi-interstices for defining a plurality of predetermined angular positions, the first detent ring being fitted into a second external detent ring likewise provided with a predetermined division and serving as a guide for the first inner detent ring. The chuck is mounted within a carrier having a bore for a shaft portion of the chuck. The angular position of the chuck is adjusted and locked by the detent ring assembly. |
