Gem faceting machine

Claim 1

In a gem faceting machine having a main working spindle which can be pivoted in a vertical plane to obtain various inclinations of its axes, further being amenable to height adjustment and being capable of being rotated about its own axis, there being means for latching the rotational position of the spindle in particular positions as well as in positions in-between the particular positions, a multiple gem mounting structure comprising: a multiple chuck mounting element provided for connection to said spindle for being turned therewith, the element having a plurality of receiving bores the bores being concentrically arranged on a common circle; a plurality of pin receiving spindles serving as chucks and respectively rotatably mounted in said bores of said multiple chuck element and being thereby radically equidistantly arranged therein; a rotatable and position arrestable actuating element including a drive element coupled for rotation to said pin receiving spindles; means on said actuating element for establishing a plurality of distinct latch and arresting positions; latch and arresting means cooperating with the means for establishing, for arresting the actuating element in any of its positions; an adaptor element for selective mounting to the chuck mounting element; and a plurality of gem mounting pins being directly without use of the adaptor element or through an adapter element indirectly mounted to the spindles of the plurality.