Apparatus for manufacturing plastic lenses
AssigneeRealite Optical Company
InventorIrving Rips
Life of this patent
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Abstract
A method and apparatus for forming lenses from a polymerizable monomeric liquid. In accordance with the method of the invention, the activated monomer is encapsulated within lens molds of unique design and is exposed to a precisely controlled atmosphere within the apparatus of the invention. More particularly, during the entire curing cycle of the monomer the molds are uniformly exposed to collimated streams of air maintained at closely controlled temperatures. The streams of air serve to precisely control the temperature of the monomer within the molds and to continuously remove the heat of exotherm from each individual mold.
Claims10
An apparatus for controllably heating an exothermic liquid mixture contained in a mold comprising:
- (a) a mold for containing the exothermic mixture;
- (b) an elongated enclosure having interconnected top, bottom, and side walls;
- (c) vertically spaced apart transversely extending first and second internal walls interconnected to said side walls of said enclosure to define an upper plenum, a lower plenum and a longitudinally extending central passageway therebetween, said internal walls each being provided with a multiplicity of spaced apart apertures;
- (d) air-circulating means for circulating air between said upper and lower plenums through said intermediate passageway;
- (e) heating means for controllably heating the air being circulated through said intermediate passageway;
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- (f) conveyor means for transporting the mold through said intermediate passageway at a controlled rate of speed.
An apparatus for forming a semi-finished blank for a multifocal lens from a monomeric liquid such as allyl diglycol carbonate to which a catalyst such as isopropyl percarbonate has been added, said mixture being contained in a mold, said apparatus comprising:
- (a) a mold for containing the exothermic mixture;
- (b) a plurality of interconnected air-circulating units, each of said units comprising:
- (1) an upper plenum having an air inlet and a bottom wall provided with a multiplicity of apertures therein;
- (2) a lower plenum having an air outlet and a top wall provided with a multiplicity of apertures therein;
- (3) a central passageway disposed between said upper and lower plenums, said central passageway being so constructed and arranged as to communicate with the central passageways of the adjacent units to form said elongated longitudinally extending central passageway;
- (4) blower means for drawing air out of said lower plenum, introducing it into said upper plenum and directing it downwardly through the apertures in the bottom wall of said upper plenum into said central passageway;
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- (5) heating means disposed within said upper plenum for controllably heating the air introduced therein by said blower means;
- (c) a conveyor means for transporting the mold through said elongated central passageway at a controlled rate of speed.
Dependencies are inferred from the claim text.