Patent GB-141606-A (GB)
Title: Improvements in apparatus for cutting or polishing gems
IPC: B24B9/16
Filed: 1918-04-11
Abstract: 141,606. Imray, O., (Ries, F.). April 11, 1918. Gems, treating.-Relates to apparatus for cutting or polishing diamonds and other precious stones of the kind in which the gem-holding means are carried by a vertically slidable carriage and are universally adjustable, and comprises means whereby a number of gems may be cut or polished simultaneously in a single machine, the gem-supporting carriages all being mounted on a common rail or bridge extending over the laps. In the construction illustrated, the bridge 94 is supported at its ends 'by standards 90, and has thereon a slide bed 96 on which are mounted two carriages 99, each of which is adjustable over a single lap by means of a rack 136 secured to the carriage and adapted to be moved by a pinion 134 rotated, through a pinion 133, by means of a lever 137 carrying a spring-pressed detent 138 with a pin 140 thereon adapted to engage in the teeth of the pinion 133. On each main carriage 99 is mounted a vertically slidable sub-carriage 109 movable in guides 100 by means of a link 119 operable by a lever 123 to enable the gem to be inspected; the carriage may be held in the raised position by a latch bolt 126 withdrawable from the hole 127 in the carriage by a finger-piece 129. Downward movement of the carriage is limited by means of a micrometer nut 144 carried on a screwed stem 105 and having divisions which may be set to a mark on a stud 103 on a cross-piece; lock-nuts 146, 147 are provided for the nut 144. The rate of grinding the gem is controlled by a lever 150, pivoted at 149, carrying an adjustable weight 152 and bearing on a pin 155 extending rearwardly from the carriage; when this is to be lifted, the lever is moved to rest on an offset support 154. The dop 210 carrying the gem 212, Fig. 8, is carried by a holder comprising a shank 158 having thereon a graduated base part 159 adapted to be set to a mark on an extension 117 of the sub-carriage and to be secured in a slot 118 in the extension bv a nut 166. The member 159 has depending therefrom a bifurcated part 161, in which is pivoted a block 170, Fig. 11, pinned to a pivot pin supported in the bifurcated part and having in its upper end a worm thread 174 adapted to be engaged by a micrometer screw 186 having thereon a graduated collar 189. The angular setting of the block 170 about the axis of the pin is indicated by a pointer 164 and graduations on the face of one of the wings of the part 161. The block is also pinned to a pivot pin 178, on the projecting ends of which are journaled the side wings of the dop-support 201; this carries a micrometer screw 194 meshing with a worm 173 on the block and having a graduated collar 198. The setting of the dop-support about the pin 178 is indicated by a pointer 179 on the pin and a scale on one of the wings of the dop-support. The dop-support carries an angularly adjustable donholder 214 adapted to be set by means of a scale on the holder and a mark on the support and to be locked in position by a collar 207, and the dop 210 is secured in the holder by means of a screw 209. The gem 212 is held in its seat by means of prongs fitting in sockets 216. Each of the main carriages is fitted with the controls and parts as above described, and when the bridge supports carriages intermediate the two end carriages, depending lugs are provided to support the parts; more than one lap may be provided if required. Specification 134,240 is referred to.