Abstract: An apparatus for making cathode ray tube screens with contoured fixtures comprises an automatic press having a rotary table with moulds radially fixed thereto, as well as a mechanism for moulding the fixtures. This mechanism has a vertically and horizontally displaceable frame carrying heaters and male dies. In operation, the frame is introduced into the mould with a screen blank and then is placed, in turn, in two locked positions in which the screen boards heating and fixture moulding, respectively, are effected.

Abstract: In the sealing of two glass surfaces together in the formation of a hermetically sealed hollow article, it is important that the opposed seal edges be uniformly complementary along their sealing extent, and a method of sagging the seal edge to a desired surface contour is disclosed.

Abstract: A method for the production of single-material optical fibers having a light conducting core supported within a protective sleeve by at least one extremely thin support component characterized by providing a blank having a core and at least one support component disposed within a protective sleeve, heating the blank to a drawing temperature, drawing the blank into a form of an optical fiber and either during the drawing or subsequent thereto, transversely stretching the support component to reduce the ratios of the thickness of the support component to its transverse width and to the thickness of the core of the fiber. In one embodiment of the invention, subsequent to the drawing, a fluid such as a gas under excessive pressure is applied internally to the protective sleeve to expand and inflate the sleeve to transversely stretch the support component.

Abstract: Tubes of transparent, translucent or opaque fused silica are made by heating a hollow cylindrical blank in a drawing zone, drawing the blank from the zone while maintaining its interior under pressure and rotating same about its longitudinal axis, and calibrating the still-plastic tube immediately upon leaving the drawing zone in a calibration zone defined by two graphite plates. Apparatus for carrying out the method includes means for heating the blank to a drawing temperature in a drawing zone, means for drawing the blank from the zone, means for maintaining the interior of the blank under pressure and means for rotating the blank as it is drawn, and calibrating means for calibrating the still-plastic tube immediately upon leaving the drawing zone including two graphite plate means disposed on metal plates through which a coolant can flow.

Abstract: A method and apparatus are disclosed for making small gas-filled beads by locating a heat deformable tube on top of a heated platen in a controlled atmosphere chamber, with a multiple, spaced knife-edge structure located on top of the tube. When the temperature of a tube is raised to its softening temperature, gravity forces the knife edges through the tube, sealing the tube into separated compartments or ampuls with gas in the interior of each compartment. The articles are cooled below the softening temperature of the tube, are separated into ampuls and then the ampuls are reheated above the softening temperature to the working temperature of the tube in a sphere forming cycle under conditions of carefully maintained temperature and pressure such that the surface tension of the glass coupled with the gas within the ampul causes the ampul to take on the shape of a sphere with uniformly thick walls and size, dependent on the temperature and pressure conditions during the reheating cycle.

Abstract: The invention relates to a method of manufacturing a tubular lamp envelope for a fluorescent lamp in which a glass tube is softened by heating, bent around abending jig by means of bending members and then cooled until the material of the tube has solidified. During the solidification the tube assumes a horizontal position and the cooperation of the bending members with the tube is interrupted.

Abstract: In the disclosed process, a multiplicity of like fibers of fusible material are arranged in a bundle which is brought to the drawing temperature. The bundle is drawn to reduce its cross sectional area while retaining its cross sectional configuration. During the drawing step, a fluid pressure is maintained in the peripheral rows of fibers which exceeds that of the remaining fibers of the bundle to maintain a substantially uniform diameter of the fiber elements in the resulting drawn fiber bundle.

Abstract: A method and apparatus for making a controlled opening or bubble in the bore of a glass clinical thermometer comprises directing a narrow light beam at the heated glass while introducing pressurized fluid into the bore. The light beam is chosen to form a diffraction pattern including a shaprly imaged area whose width corresponds to the bore diameter. The diffraction image area width is used to obtain the desired bubble dimensions.

Abstract: Quartz glass element, such as a diffusion tube useful in the production of semiconductor elements, capable of forming an outer layer of uniformly fine crystalline silica such as cristobalite or tridymite when heated to a temperature at which such crystalline silica forms containing crystallization promoting nuclei having a rate of diffusion in quartz glass less than that of sodium at elevated temperatures. Such nuclei are present in the outer half of the element wall and the maximum concentration of such nuclei is at the surface of the element and then diminishes inwardly. When the quartz glass element is exposed to elevated temperatures, the nuclei promotes the formation of the outer layer of uniformly fine crystalline silica which imparts thermal dimensional stability for extended periods of use at elevated temperatures.

Abstract: In arc discharge lamps containing a mixture of metals and halogen, and especially where an unvaporized excess of one metal is present, lamp color is very sensitive to end chamber shape. Color uniformity in production lamps using quartz arc tubes varying appreciably in diameter and wall thickness is greatly improved by molding end chambers of constant size and shape in the ends. The chamber may be formed at the time the end is pinched and the electrodes sealed in by using pinching jaws having a mold defining portion and momentarily pressurizing the arc tube to expand the heated and still plastic end into the mold. In production all lamps will have their ends expanded or belled to some extent, more in lamps close to the minimum diameter limit and less in lamps close to the maximum diameter limit.