| 摘要 |
<p>1,020,149. Coating composite articles; grinding lenses. TEXTRON Inc. Jan. 5, 1965 [Jan. 30, 1964], No. 421/65. Headings B3D and B3F. Apparatus for moulding on to a lens blank a lens block for holding the blank in a lens edging machine comprises a mould block 146 with a cavity 150 open at one side against which a lens blank may be clamped, means 30 for supplying molten metal to the cavity to cast the lens block and adhere it to the lens blank, and locating means for directing beams of light through the mould block on to the lens blank to enable it to be properly positioned on the mould block. There are two identical mould assemblies 140 mounted on a plate 21 oscillatable about a turret 24 so that either may be brought beneath the nozzle 50 of the part 30 containing a low melting point alloy kept molten by electric heaters 48. Flow of melt through the nozzle is controlled by a spring- loaded valve 38 actuated through levers by a handle 70. The pot is carried by a slide 28 spring pressed towards the mould and retractable by a handle 110. A float 130 with rod 132 indicates the level of the molten metal in the pot. The mould comprises an ejector pin 156 actuated through a rack and pinion mechanism by a handle, and the interior of the pin 156 carries a nylon rod 166 through which a light beam passes from a source 176 in a reflector 174 to assist in locating the lens blank on the mould block. Beams also pass through two other openings in the mould block outside the mould cavity for the same purpose. The lens blank is clamped to the open side of the mould cavity against a sealing ring 154, by spring- pressed fingers 181-183 which may be retracted for removal of the casting by a handle 196. Grinding lenses.-Projections 180 in the mould cavity form holes in the cast lens block which serve to locate the lens block in the edging machine.</p> |
