Abstract: The present invention is directed to a four-step process for molding glass articles of high precision and excellent surface figure. A glass preform having an overall geometry closely approximating that of the desired final product is placed into a mold, the mold and preform are brought to a temperature at which the glass exhibits a viscosity between 10.sup.8 -10.sup.12 poises, a load is applied to shape the glass into conformity with the mold, and thereafter the glass shape is removed from the mold at a temperature above the transformation range of the glass and annealed.

Abstract: A system for forming hollow pressed glass articles utilizes a flow of cryogen that is mixed with air to provide a cooling gas that enables newly pressed articles to be removed from their molds after a thin skin of solidified glass has been formed on internal surfaces of the articles to strengthen the newly formed articles and to give them shape stability. Two flows of cryogen are used, one being a gentle, substantially continuous flow of cryogen gas from a low pressure source, the other being a controlled intermittent flow of cryogen vapor in liquid and/or gaseous form from a high pressure source. To assure a proper introduction of cryogen vapor, and to prevent debilitating accumulations of ice within and about the tube that is used to inject high pressure cryogen, the high pressure injector tube is surrounded by a low pressure cryogen flow tube, through which a flow of low pressure cryogen gas is maintained on a substantially continuous basis.

Abstract: According to the invention, a cryogenic liquid as liquid oxygen is vaporized in a heat exchanger by air, which air is thus cooled and further used to blow bottles or the like manufactured at the end of the line where glass is melted and refined by burners using the gaseous oxygen.

Abstract: An apparatus for blow molding glass articles uses a mixture of cryogenic fluid and ambient air as a blowing fluid. The apparatus includes gas inlet means positioned to direct a flow of blowing fluid into the center of a blow mold, insulated manifold means to mix ambient air and a cryogenic fluid as the blowing fluid, means to feed the mixture into the gas inlet means, means to pressurize the ambient air, conduit means for directing ambient air into the insulated manifold, and injector means for introducing cryogenic vapor into the conduit means.

Abstract: Methods for forming glass articles such as bottles and the like utilize pressurized flows of a cold blowing gas that is delivered from an insulated manifold into mold cavitites which are being used to mold glass articles. The cold blowing gas is a mixture of compressed cryogen vapor and ambient air that has been dehumidified, with the injection of the cryogen vapor into the ambient air being performed in stages, and utilizing a technique of cyclically operating and defrosting a plurality of cryogen injectors to assure a proper introduction of cryogen vapor and to prevent debilitating accumulations of ice about the cryogen inlets. The use of cryogen vapor in the blowing gas hastens cooling and solidification of newly formed glass articles so that the time during which the articles must be retained in their molds is significantly reduced. Reductions in mold retention times enable the apparatus to be operated at increased speeds, whereby its productivity is significantly increased.

Abstract: A parison mold portion (20) of an individual glassware molding machine, of the type having a parison mold (22), a split neck ring (28), a neck ring holder (30), an upper receiver cap (40), and a parison plunger (116) , is provided with means for cooling the neck ring (28) and the parison mold (22). The means for cooling the neck ring (28) and the parison mold (22) includes a plurality of first cooling holes (214) in the upper receiver cap (40), a plurality of second cooling holes (216) in the neck ring (28) that communicate with the plurality of first cooling holes (214), and a plurality of third cooling holes (230) in the parison mold (22) that communicate with the plurality of second cooling holes (216).

Abstract: A method of manufacturing practically stria-free, bubble-free, and homogeneous quartz-glass plates of any desired configuration and with a surface area that exceeds the cross-section of the full circular quartz-glass cylinder that is employed as a starting material. The cylinder is continuously lowered into a furnace shell flooded with an inert gas, in which it is heated to a flowing temperature in the range of 1700.degree. to 1900.degree. C. until some of the quartz-glass flows off into a graphite crucible. The crucible is preferably clad with zirconium-oxide.

Abstract: An optical element, consisting essentially of an amorphous compound and having a varying refractive index, is prepared by introducing a melt of the material into a mold and cooling it in such a manner that the material gradually solidifies, while simultaneously applying a programmed pressure to the cooling melt. When the material is fully solidified, it possesses a refractive index gradient. An element manufactured by this method has a capacity for guiding and focusing light.

Abstract: Methods and apparatus for forming glass articles such as bottles and the like utilize flows of pressurized cold cryogen vapor that are introduced into mold cavities which are being used to mold glass articles. The cold cryogen vapor hastens cooling and solidification of the articles so that the time during which the articles must be retained in their molds is significantly reduced. Reductions in mold retention times enable the apparatus to be operated at increased speeds, whereby its productivity is significantly increased. Productivity increases of 15 percent and often more can be achieved at relatively low expense. The use of cold cryogen vapor introduction into mold cavities is applicable to a variety of glass molding techniques including molding and blow molding.

Abstract: A mold for producing a glass article having an opening and a protruding hollow portion, said mold comprising(A) a female mold comprised of a main female mold member and an auxiliary female mold member, the inside shapes of the depressed portions of the two female mold members substantially defining the outside shape of the glass article,(B) a male mold defining the inside shape of that part of the glass article, and(C) a gas exhaust port formed in an inmost position of the depressed portion of the auxiliary female mold member, and/or(D) a gas introducing port formed in the male mold in a position facing the depressed portion of the auxiliary female mold member.And a method for producing the glass article by using the mold.

Abstract: A newly-moulded article of glassware is positioned on a dead plate with a central opening of the dead plate beneath a central region of the bottom of the article and a plurality of grooves or openings extending from beyond the article to beneath the bottom thereof. Air is sucked through the central opening so that it flows through the grooves or openings past the bottom of the article. Air is also blown on the sidewalls of the article through a plurality of nozzles uniformly spaced around the article.

Abstract: A method of cooling a blank mould which is used for making a parison in a glass container forming machine. The mould is provided with air passages which communicate with air passages in a baffle of the mould when the baffle is in position on the mould and air is blown through the passages in the baffle into the passages in the mould to cool the mould. The method may be used whether the parison is formed by blowing or by pressing. A baffle for use in the method is also claimed.

Abstract: An improved acousto-optic device and method featuring an acousto-optic element having an alkali metal oxide-tellurite glass composition comprising at least 92 wt % tellurium dioxide and one or more alkali metal oxides selected from the group consisting of sodium oxide and potassium oxide. A process for decreasing the acoustic attenuation of the aforementioned glass composition by annealing is also disclosed.

Abstract: The present invention relates to the preparation of polarizing glasses from silver-containing glasses characterized by the presence of metallic silver particles therein and/or by being photochromic through the inclusion of silver halide particles therein selected from the group of AgCl, AgBr, and AgI. The method contemplates extruding the glass at a temperature between the annealing and softening points of the glass at a sufficiently high applied pressure to elongate the metallic silver and/or silver halide particles to an aspect ratio of at least 2:1 and up to 30:1 and greater. The extrudate is cooled in a manner to prevent the elongated particles from resuming their original shape. Dichroic ratios of up to 5.0 are achievable where the elongated particles exhibit an oblate configuration.

Abstract: A method of producing clad glass rod of uniform diameter from which an optical fibre is drawn. The rate of drawing of the rod from a glass melt and the diameter of the drawn rod are sensed and the sensed values are fed to a coarse open loop control and a high gain closed loop control which regulate the draw speed of the rod and the movement of a cooling jacket which cools the rod as it is drawn.

Abstract: A method for forming a glass article of a devitrifiable glass having an optimum working temperature in the vicinity of its liquidus temperature, wherein the temperature of the molten glass is, during the molding operation, maintained at considerably higher temperature than both the optimum working temperature and the liquidus temperature, the molded article is passed through water or a layer of wet granular materials floating in water before the temperature of the molded article drops down to the liquidus temperature and before the molded article is deformed to rapidly cool the article to a temperature below the devitrifying temperature.