Abstract: A method for the manufacture of a preform of barium containing heavy metal fluoride glass comprising a core and a jacket for drawing infrared light waveguides for optical communications technology by casting molten glass onto a predetermined body of solid glass. Hitherto, such a method was executed such that molten core glass was cast into a tube of jacket glass. In order to achieve thicker preforms, one proceeds such here that a solid row of the core glass is surrounded with molten jacket glass. The boundary surface between core and jacket of the generated preform can be improved in the method disclosed herein that the surface of the solid rod is etched before being surrounded with the jacket glass. A nearly perfect boundary surface is obtained by etching with a ZrOCl.sub.2 solution.

Abstract: An invert/neckring mechanism for an individual section (I.S.) glass forming machine including a rectangular shaft and a pair of neckring arm holders having a central passage which mates with the rectangular cross-sectional shaft to limit the movement between the shaft and the arm holders to axial movement all rotated through the invert arc by a hydraulic actuator in juxtaposition therewith. A plurality of springs bias the arm holders together to a closed position and a hydraulic double piston cylinder assembly is mounted adjacent to the shaft between the arm holders to open and close the arm holders.

Abstract: Each glass plate, brought to a high temperature, arrives flat on a conveyor by resting there by its lower face, is picked up by its lower face, is turned over to bring its initially lower face into the upper position, and is then placed on a bending form the profile of which it assumes. A device for accomplishing this process has a pivoting plate capable of turning the glass plate over, a bending form, optional pressing means, and a frame for conveying bent glass plates to a succeeding work station.

Abstract: An optically activated bleaching process effective to permanently modify the color of surface-colored silver halide-containing photochromic glasses produced by thermal reduction treatments is described, wherein the glass is coincidentally exposed, for an effective time interval, to (i) a source of high energy light and (ii) a heat source. The process reduces the relatively strong absorption peaks characteristic of the initially colored glass, resulting in a permanent bleached appearance.

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: Incorporation of fluorine into a porous silica body, such as an unsintered body produced by a sol-gel method, by VAD or OVPO, reduces or eliminates bubble or pore formation upon re-heating of the glass formed by sintering of the porous material. Effective fluorine concentrations are between 0.01 and 5% by weight. The invention can be used advantageously in producing preforms and optical fiber.

Abstract: The invention relates to the precise positioning of sheets of glass on a conveyer, particularly in an installation for curving sheets of glass. Positioning the sheets of glass by means of a combination of actions, in whole or in part, comprising orientations, longitudinal centerings and transversal centerings.

Abstract: A plunger assembly is provided wherein the precise centering of the perforated section of the cooling tube within a plunger of an I.S. type glass forming machine is achieved by securing the cooling tube to the plunger. The base of the plunger has a recess which wedgingly receives a plurality of equally spaced wedge elements secured to an annular collar fixed to the cooling tube. The wedge elements are sufficiently tall that they will extend beyond the plunger base, thereby defining exit openings through which plunger cooling air can be discharged.

Abstract: Roof of a working tank or of a glass melting furnace having a basin containing molten glass and covered by the radiation roof of highly refractory firebrick material, in which the roof is constructed with horizontal supporting elements in the form of straight arches (3) bearing the load of the roof (1) and spanning the tank at intervals, and with horizontal slabs (4) covering the open intervals between the supporting elements (3) and laid crosswise between the supporting elements (3).

Abstract: In a press-molding device for lenses, an upper surface of a drag is formed into a molding surface, and a lower surface of a cope is formed into a molding surface. An inner peripheral surface of a guide mold portion is in contact with an outer peripheral surface of the drag, and has an axial length longer than that of the outer peripheral surface of the drag so that the inner peripheral surface extends upwardly from the molding surface of the drag. The cope is capable of sliding along the inner peripheral surface. A pressure plate is in contact with an upper surface of the cope before pressing, and is abutted against the upper surface of the guide mold portion by the pressing. A glass preform to be molded is arranged between the molding surfaces of the respective cope and drag. The cope is pressed from above through the pressure plate, thereby molding the glass preform to a lens. The guide mold portion may be divided into a pair of upper and lower portions.

Abstract: In an apparatus for molding glass articles, a plurality of processing chambers including a heating chamber, a press chamber and a cooling chamber are arranged in order along a predetermined circular transport path. The processing chambers are surrounded by a case within a furnace body. A rotary table is driven for intermittent rotation about an axis thereof. The transport path extends in concentric relation to the axis of the rotary table. The rotary table extends radially outwardly to a position below the case. A plurality of sample mounts are mounted on the rotary table and are arranged along the transport path in spaced relation to each other. The sample mounts extend into the processing chambers through a slit formed in a bottom wall of the case. A plurality of molds each having accommodated therein a glass preform to be molded are mounted respectively on the sample mounts.

Abstract: An apparatus for ensuring alignment during opening and closing of mold halves in an individual section (I.S.) glassware forming machine has a cylinder containing a pair of mutually reciprocating pistons linked to a pair of mold half actuating shafts. A pair of gear racks, each linked to one of the pistons, mesh with a common idler gear. A plug and cushion combination cushion the opening stroke of the mechanism.

Abstract: Improved burner constructions for gas-fired infra-red generators having ceramic fiber matrix through the thickness of which gaseous combustion mixture is passed and as it emerges it is burned to heat emerging surface to incandescene. Burner matrix can be loaded with silicon carbide particles to improve its emissivity, can be made water repellent and its uniformity can be improved. Burner body can be casting, with sheet metal addition to form a baffle and air seal and to grip matrix edges. Combustion mixture plenum can have movable partition assembly separating it from air seals, to adjust portion of matrix at which incandescene is generated. Metal screen can be stretched in front of incandescent surface to assist with low-temperature operation. Large size matrix can have central support fitted and secured to back of burner body. Air seal can be provided by narrow curtain of air extending around internal faces of burner body.

Abstract: A heat softened glass sheet is shaped between a contoured upper mold and a flexible lower ring mold. The flexible shaping surface of the lower mold has a generally flat surface configuration as it initially contacts and lifts the peripheral portions of the glass sheet off a series of conveying rolls. The lower mold continues to bias the glass sheet against the upper mold and deforms to substantially compliment a corresponding peripheral portion of the contoured upper mold.

Abstract: An apparatus and method for bending glass sheets. In a first embodiment a heated glass sheet is moved into a bending section by rollers which are retracted to drop the heated glass sheet onto a mold where the glass sheet sags into a desired bent shape, then quenched between quench heads and lifted off the bending mold up to the upper quench head by air pressure, the rollers then close beneath the glass sheet and the glass sheet is deposited onto the rollers for conveying to a cooling station. In a second embodiment, the hot bent glass sheet is transferred on a mold from a bending section by a first shuttle to a position between the quench heads for quenching then removed from the mold by blowing air through the lower quench head until the glass sheet contacts an upper second shuttle which is transported to a blow-up section where the sheet is lowered onto a roller conveyor to a cooling section.

Abstract: An article transfer mechanism to transfer glass articles between a receiving position and a delivering position, in straight line, between one or various sections of a process of manufacture of glass articles. The mechanism includes a frame. Guide shafts attached to said frame. A sliding support attached at said guide bars. A first planetary transmission coupled between said drive means and the sliding support, which through of a rotational movement of the transmission, the sliding support is moved in a straight line, with a backward-forward movement over said guide bars. A second planetary transmission coupled to said first planetary transmission, through the sliding support to generate a far larger stroke of the transfer mechanism.

Abstract: To prevent weakened corners when forming a U-shaped discharge tube with sharp corners (28, 29) during a bending operation from a straight tube, two glass tubes (1, 3) having a wall dimension suitable for a compact fluorescent tube are fused to a central tubular glass element (2) of thicker wall dimension so that, upon bending into U-shape with sharp corners (28, 29), the thicker wall portion can stretch and form the essentially right-angle corners of requisite wall thickness. Preferably, during the heating steps for forming the glass, the initially straight glass portions (1, 2, 3) are rotated.

Abstract: A method for bending a glass plate for a laminated glass comprises a step of heating at least two glass plates separately at a temperature suitable to conduct bending operation and bending them; a step of gradually cooling each of them; a step of transferring the at least two glass plates onto a bending ring mold in an overlapping state; and a step of heat-shaping the overlapping glass plates on the bending ring mold so that the surfaces of the glass plates are fitted to and are in coincidence with each other.

Abstract: The method of the present invention consists of the steps of heating an area along the length of a small diameter glass tube while the tube is being rotated, pulling the heated tube using an unidirectional force to rapidly extend the heated area while mechanically maintaining the heat source centrally located along the portion of the tubing being extended. The extended tubing is subsequently cooled and separated at the narrowed portion to produce two capillary tubes.

Abstract: In glass enamel coating compositions containing a glass frit system and a vehicle therefor, the improvement comprising the presence therein of copper sulfide or copper sulfate as an anti-stick agent; the resulting coatings being effective for application to glass sheets which are subsequently subjected to high temperature forming procedures.