Abstract: A method of strengthening glass plate is provided. A plasma treating process is performed on a glass plate so that a surface pore variation of the glass plate after the plasma treating process is reduced relative to the surface pore variation of the glass plate before the plasma treating process, wherein the surface pore variation is a variation degree of surface pores in different unit areas of the glass plate. In the mean time, a melted network crosslinking structure is formed on the surface of the glass plate. Based on the above-mentioned mechanisms, the glass plate is strengthened. The plasma treating process is conducive to strengthen the glass plate whether the plasma treating process is performed before or after the conventional chemical strengthening process.

Abstract: In order to avoid deposition of evaporating alkali compounds on an inner surface of a hollow glass body during thermal processing to form a glass container from the hollow glass body, an overpressure is provided in the hollow glass body during the thermal processing. Either rinsing the hollow glass body with a gas, such as air, or at least partially closing the glass body at one end so that sufficiently rapid pressure equilibration is avoided, can provide this overpressure. The glass containers made by these methods are especially suited for food or pharmaceuticals because they have a reduced alkali release from their inner surfaces, for example at most about 2.0 mg/l sodium oxide.

Abstract: An apparatus and a method for cutting float glass is disclosed. A burner and water spray are arranged to cause thermal stress cracking along a cutting line extending along a continuous glass ribbon, parallel with the edge of the ribbon. The thermal stress cracking is initiated without the use of mechanical force. Preferably, the burner is used to initiate the thermal stress crack, by increasing the power supplied to the glass.

Abstract: To provide a method and apparatus for parting a glass rod without causing a crack or rupture at a grasped root portion of the glass rod in parting the glass rod for producing a glass preform. The apparatus for parting the glass rod in a predetermined length by grasping both ends of the glass rod 11 is characterized by comprising a supporting unit 18 of Y-character shape for supporting an intermediate position between both ends of the glass rod 11 from the lower part, the supporting unit 18 having a carbon sleeve composed of a cylindrical body that is rotatable around each of two leg portions making up a forked leg portion as an axis, the carbon sleeve being rotatable along with an axial movement of the glass rod.

Abstract: There are provided a method of manufacturing a glass substrate for information recording media that allows the inner and outer peripheral edge surfaces of the glass substrate for information recording media to be smoothed easily and inexpensively, a glass substrate for information recording media manufactured using this method, and an information recording medium using this glass substrate. A donut-shaped glass disk for information recording media having an outer peripheral edge surface and an inner peripheral edge surface is prepared. At least one of the outer peripheral edge surface and the inner peripheral edge surface of the glass disk is smoothed by melt-heating to a temperature at or above the softening point of the glass by irradiating with at least one laser beam.

Abstract: The apparatus for melting off a glass top part from a hollow glass blank has individual burner sections (3) each containing at least one burner nozzle. The individual burner sections (3) are held in a cutting plane and movably connected with each other. A control device (4a, 4b, 5) controls the respective positions of the burner sections (3) so that they fit any arbitrary outer contour of the hollow glass blank (1). The control device (4a, 4b, 5) holds and maintains the burner sections (3) at a constant distance from the exterior surface of the hollow glass blank (1). The burner device with the burner sections (3) is mounted on two half frames pivotally connected with each other for better access to the glass object (1). This apparatus separates the glass top part from oval or triangular glass objects, which should be cut at an inclined orientation, in a single step.

Abstract: To provide a method and apparatus for parting a glass rod without causing a crack or rupture at a grasped root portion of the glass rod in parting the glass rod for producing a glass preform.

Abstract: A method for fusing an optical fiber preform comprises fusing the preform while blowing an oxidative gas against the preform to be fused from upper and lower directions of a fusing burner unit. An apparatus for carrying out the method includes a plurality of nozzles for preventing deposition of silica cloud, which are each set at an angle, &thgr;, of blowing the oxidative gas relative to the preform being drawn such 20°≦&thgr;≦60°.

Abstract: A method for opening or sealing glass ampoules (38) by melting the glass with the help of a jet (36) of a hot medium, characterized in that the medium is an atmospheric plasma, produced by an electric discharge.

Abstract: A method for manufacturing a fluorescent lamp that can achieve stable luminous characteristics and discharge characteristics and also does not suffer from cracks in the interconnected portion of the glass tubes while handling or lighting the fluorescent lamp is provided. Interconnecting portions located in the vicinity of open end portions of glass tubes that are positioned adjacent to each other are heated respectively from inside to form a welding portion, and then, the glass tubes are thrust against each other and thinned by conducting a preliminary tapping of the welding portion from inside using hammers. Next, the welding portion is opened by conducting a main tapping to form an interconnected portion, and end portions in the vicinity of the interconnected portion are closed by heating and melting, and then the end portions are molded.

Abstract: A method for manufacturing a glass tube used for a fluorescent lamp having an arc tube constructed by joining a plurality of glass tubes is provided. According to this method, a straight glass tube held at both ends is rotated, and a predetermined cutting portion of the glass tube is softened by heating, and then the glass tube is moved in the heated state in the direction toward the predetermined cutting portion to form a glass accumulated portion at the area of the predetermined cutting portion. Next, the glass tube is drawn away in the direction receding from the predetermined cutting portion, and the predetermined cutting portion of the glass tube is cut into two glass tubes having self-closing end walls. In this way, the end walls of the self-closed glass tubes can be formed thicker and more uniform compared to those obtained by the conventional techniques, and the mechanical strength of the end walls also can be improved.

Abstract: A method for fusing an optical fiber preform comprises fusing the preform while blowing an oxidative gas against the preform to be fused from upper and lower directions of a fusing burner unit. An apparatus for carrying out the method includes a plurality of nozzles for preventing deposition of silica cloud, which are each set at an angle, &thgr;, of blowing the oxidative gas relative to the preform being drawn such 20°≦&thgr;≦60°.

Abstract: A method for cracking off glassware (1), whereby glass pieces (1) are subjected to a laser radiation treatment (F). In a first step, the part of the glassware to be cracked off (3) is subjected in a region thereof to the action of a continuous laser radiation beam (F) or to continuous laser radiation beams (F) such that the beams touch the part (4) in the region with a power density per unit area less than 30 W/mm2. In a second step, successive points along a line in the part to be cracked off, which has been subjected in the first step to the action of a continuous laser radiation beam (F), are subjected to the action of a focused pulsating laser beam (F) with power less than 250 W, such that, during this second step, the successive points, in the line of the focused laser beam's successive impact points on the part to be cracked off (3), are spaced from each other.

Abstract: The invention relates to a method of performing surface treatment on a preform manufactured in an installation for manufacturing or building up preforms having supporting cores, the installation including at least rotation means having a horizontal axis of rotation and two mounting points between which the supporting core of the preform to be manufactured or built up is mounted, plasma-torch and material-supply means disposed radially relative to the supporting core and mounted to move in axial translation relative to and parallel to the supporting core so as to make the preform around the supporting core, the preform being manufactured or built up by effecting successive passes with the plasma torch while material is being supplied.

Abstract: Disclosed is a method for the heat-softened severance of thin-walled glass tubes or plates with a wall thickness of no more than 0.2 mm, wherein the glass is softened on a width of no more than 0.4 mm, the softened area is reduced by drawing to a wall thickness of no more than 0.05 mm, and then is separated by additional heating in the drawn-out area.

Abstract: A machine to automatically cut-off one end of a cylindrical hollow glassware article, comprising: a support structure including a shaft; an intermittent rotary driving mechanism mounted on the shaft, providing a plurality of positions corresponding to article charging, cut-off, fire finishing and discharge positions; a lower intermittent rotary table mounted on said shaft and rotary coupled to the intermittent rotary driving mechanism, including a plurality of burners equally distributed on its periphery, to cut-off a leftover piece at a lower end of the article and fire finishing the cut-off end thereof within a cut-off cycle; an upper intermittent rotary table coupled to said lower table, comprising a plurality of chuck supporting and actuating mechanisms, equally mounted thereon, each including a chuck having fingers to grip an upper end of the article at a charging position, bring down the gripped article at a cut-off position placing its leftover piece in a burner to be cut-off and fire finished and lift

Abstract: An apparatus and method for forming a decorative pattern on glassware having an edge that includes a base, a forming tool, actuation means and control means. The forming tool is mounted on the base. The tool is moveable between a first position and a second position. The tool engages the edge of the glassware at the second position to form the decorative pattern on the edge. The actuation and control means move the tool from the first position to the second position. The method of the invention includes the steps of (a) moving the glassware along a predetermined path; (b) heating the edge; and (c) engaging the edge with a forming tool as the tool is being moved along the predetermined path to form the decorative pattern on the edge of the glassware.

Abstract: The invention is directed to a method for controlling the free deformation of thermoplastic material in an automated process for processing the material to form articles. These articles are especially ampules, small bottles and the like produced from glass tubes. In this method, in order to obtain a high dimensional accuracy of the article, a corrective action is carried out by applying heat to the starting material in the deformation region in the heating phase. This corrective action takes place in dependence on a desired-value/actual-value comparison of the deformation of a workpiece achieved in a predetermined working step. In order to exclude interference influences in the development of the deformation, the measurement of the deformation achieved, the desired-value/actual-value comparison and the corrective action are carried out in situ on one and the same workpiece during shaping of the deformation in the heating phase.

Abstract: A glass article cutting method by which a glass article can be cut not only along a linear line but also along a curved line of a desired profile and can be cut comparatively readily even if the glass article has a concave or convex portion on a face thereof or even if the glass article has a complicated three-dimensional profile. A conductive coating material such as colloidal carbon is applied in a linear line or a curved line on a surface of a glass article to be cut, and a high voltage is applied from a pair of positive and negative electrodes to the line of the conductive coating material to energize the conductive coating material to generate heat thereby to cut the glass article by thermal stress caused by the heat.

Abstract: An outline is cut in a glass sheet to form an inner zone and an outer marginal zone. The glass sheet is positioned on a support which supports the inner zone and marginal zone from below. A carrier is arranged such that suction pads thereof adhere to the inner zone, and such that a beveled bottom surface of a mechanical removing device carried by the carriage contacts an outer edge of the marginal zone. When the carriage is raised, the suction pads move up relative to the mechanical removing device. The inner zone is raised, but the outer edge of the marginal zone is restrained against upward movement by the mechanical removing device so that the marginal zone breaks along the outline.

Abstract: The transverse cross section of a body is modified by the steps of: a) determining the extent to which the body has material in excess of a desired shape at a plurality of points, b) exposing the body to a local heat source having a temperature sufficiently high to remove material from the surface of the body, and c) moving the surface of the body in relation to the source at a speed which decreases in regions where the body has material in excess of the desired shape so as to remove more material from such regions than from other regions. In a preferred embodiment, the body is an optical fiber preform, the local heat source is the fireball of a plasma torch, and the body is moved relative to the torch by rotating the preform at a controllable angular velocity while the torch is translated along the length of the preform.

Abstract: A glass sheet has marginal zones thereof removed by (a) subjecting the marginal zones to a heating flame, and (b) raising the glass sheet (during or after the flame heating) while restraining upward travel of the marginal zones. The lifting is performed by suction cups which depend from a movable carriage, and the restraining is performed by removing members having inclined lower faces disposed over the marginal zones. The removing members are connected to rods which carry the suction cups, the rods and removing members being relatively movable upwardly and downwardly. The rods are horizontally adjustable relative to the carriage for repositioning the suction cups and removing members relative to a glass sheet.

Abstract: A glass vessel, in particular an ampoule, having a prestress produced at a predetermined spot of the vessel which permits an automatic opening of the vessel at the predetermined spot following scratching by means of a suitable tool. The prestress, which is produced exclusively by means of an earlier thermal treatment without the application of a tool exhibits a stress profile in which an initially produced annular tensile stress ring, is overlapped at a predetermined spot by a point-shaped compressive stress zone that is produced subsequently.

Abstract: A sectional curved article e.g. an automotive window is made by cutting a piece of glass, shaping the piece of glass, cutting the shaped piece to provide inner and outer segments. The edges of the segments are seamed, and the segments chemically tempered to provide a sectional curved automotive window having an opening in the outer segment to receive the inner segment.

Abstract: A method of manufacturing a low-pressure mercury vapor discharge lamp with a discharge vessel comprising two or more substantially parallel co-extending glass discharge tube portions (4 and 5) interconnected through a coupling which extend transversely to the wall of said tube portions. First, the inner wall of an elongate tube is provided with a luminescent material. Then, while heating at least a short zone of the wall, the elongate tube is then divided into two portions. End walls are formed during the division on which the luminescent layer extends the thickness of the tube wall and the temperature of the heated zone are chosen so that no particles of the luminescent material are enclosed in the glass of the end wall during said dividing process and fracture is avoided at least after cooling.At least at the area of the transition from the end wall to the tube wall, the ratio AB/CD is 0.4 to 0.8.

Abstract: In a process for heating an object made of thermoplastic material along a predetermined zone, a ring of burners arranged in series is guided along the zone and heats this zone, the zone forming a closed path and approximately matching the outer contour of the object; in a device for implementing the process, series-arranged burner units circulate on a path covering the zone to be heated, the units being guided along a closed loop.

Abstract: Silica glass having a substantially smooth, planar surface is formed by floating sintered silica glass on a molten metallic bath. The molten metallic bath is maintained at a sufficiently high temperature to heat-polish the sintered silica glass surface which is in thermal contact with the bath to form a substantially smooth, planar surface. A method for producing silica glass includes floating sintered silica glass on a molten metallic bath to provide the sintered glass with a substantially smooth surface. The resultant silica glass has many applications, but has particular utility for semiconductor substrates, integrated circuit masks, and other electronic applications.

Abstract: Glass shapes and sheets are cut directly from a heated glass ribbon while maintaining the optical quality of the cut glass. A float glass ribbon is removed from a glass forming chamber and prior to annealing, a line of cut is heated to its softening temperature. A blade arrangement thereafter penetrates the glass along the heated line of cut to sever the glass. During the line heating and cutting operation, the overall glass temperature is maintained above the strain point of the glass.

Abstract: A sliding support table to support a continuously advancing glass ribbon during severing. The ribbon is supported by and moves over the sliding support table which moves along the direction of the glass ribbon travel between stationary upstream and downstream supports. Top and bottom line heaters supported on the table direct flames towards the major surfaces of the glass ribbon along a line cut. A blade and anvil arrangement supported on the table, sever the glass along the heated line of cut when the line of cut is positioned therebetween. The table advances along with the glass ribbon to support the ribbon during the heating and severing operation. The line heaters and blade and anvil arrangement may provide both a linear or nonlinear line of cut.

Abstract: A machine for making and painting test tubes by painting open-ended tubes and then fusing and severing them to form individual test tubes.Substitutable paint applicators varying in width, adjustable in location relative to the open-ended tubes, apply paint thereto by means of wiping action caused by rotating said open-ended tubes while in engagement with said paint applicators. The open-ended tubes are then individually fused and severed intermediate their open ends to form, from each open-ended tube, two separate test tubes having painted bands of the desired width and at the desired location, including painted bands which are contiguous with the open ends of the test tubes.

Abstract: In a laser beam glass cutting method, a glass article to be cut (for example a moulded tumbler having a moil) is maintained at a high temperature below the softening point of the glass and then the glass is repeatedly irradiated with a laser beam along the required cut-off line by rotating the glass. During this step, a tensile force is applied by gravity or by a mechanical device to the part to be cut off. Following removal of the part, the edge of the glass is irradiated again with the laser beam to effect fire-polishing thereof, so as to improve the shape of that edge. During the irradiation by the laser beam, an auxiliary inert gas is blown into the glass article to prevent glass deposition.

Abstract: A method for sealing a mount including a wafer in a neck of a stationary cathode-ray tube comprises positioning a first tier of burner tips completely around the neck such that the burner tips are aimed nonradially along directions tangent to a first circle, the plane of the first circle being aligned along the wafer. The first tier of burner tips is split into at least first and second radial segments, each segment being connected to means for moving the segment toward and away from the neck. The first tier of burner tips, while remaining stationary, provide a vortical pattern of flames around the neck. The radial segments are then removed from around the stationary neck sufficiently to allow the tube to proceed along a conveyor line.

Abstract: Apparatus for sealing a mount including a wafer into a neck of a cathode-ray tube oriented along an axis comprises two tiers of burner tips. The first tier is disposed completely around the axis at a first distance therefrom and similarly aimed nonradially along directions tangent to a first circle. The second tier of burner tips is disposed completely around the axis below the first tier at a second distance from the axis and similarly aimed nonradially along directions tangent to a second circle. The first distance and the diameter of the first circle are greater, respectively, than the second distance and the diameter of the second circle.

Abstract: A machine for trimming hollow glass articles includes a support in which a semi-finished article is held stationary and immovable, and a pair of split oscillatory burners for flame cutting at least one excess end of the semi-finished article, the burners being oscillatable relative to the stationary article in order to effect the required flame cutting operation.

Abstract: A burner for a machine for the thermomechanical treatment of glass tubes is oriented obliquely with respect to a path of movement followed by the glass tubes in the machine. The burner is connected to a fuel delivery pipe and is provided with nozzles arranged in tiers in the desired direction.

Abstract: According to the method of aseptic and antiparticulate opening of a sealed glass ampul, one end of the ampul is submitted to a powerful thermal flux produced by flame tongue generating sources on a very localized zone for a time period sufficient to obtain melting of the glass while maintaining the adjacent portion thereof at lower temperature for preserving its rigidity, such time period being the shorter the smaller that volume of gas contained in the ampul which is quickly brought to an increased temperature and pressure to cause the ampul to be opened up in the considered molten zone.

Abstract: The present invention relates to a working method for the automatic bursting-off and grinding of the edges of glasses, particularly automatically manufactured shaft or stemmed glasses as discharged from the glass blowing automaton upon attaching the stem including the base or foot, as well as an automatic machine for carrying out such method.

Abstract: In a method for sealing a glass stem into the neck of an electron tube, the stem, which is supported on a mount pin, is positioned in the neck, which is longer than desired. The neck is then heat sealed, as by fusion, to the stem, and the excess glass or cullet is cut off, whereby the cullet falls on, around and sticks to the mount pin. The novel method includes releasing the cullet from the mount pin without substantially fracturing the cullet. Then, the released cullet is removed from the vicinity of the mount pin, again without substantially fracturing the cullet.

Abstract: A method of cutting glass fiber strands is disclosed wherein said strands are driven across the beam of an interruptable laser. The laser beam melts the strand at each pulse of the beam cutting the strand into short lengths. The cut strands can be immediately collected and packaged or can be further subjected to a drying procedure prior to packaging. The strands formed by this method have fused and comparitively even ends as opposed to the ragged uneven ends of mechanically chopped glass strands.

Abstract: The disclosure is of apparatus including two pairs of metal gripping blocks held together by a spring and mounted adjacent to wedge blocks carrying wedges for opening each pair. An operating plate is provided which drives the apparatus to cause the wedge blocks to open the gripping blocks to permit a length of capillary tubing filled with mercury to be inserted between the pairs of gripping blocks. The apparatus is then driven to cause the tubing to pass through a flame positioned to melt the tubing at a desired location and to form two separate seal portions at this location which are gripped by the two gripping blocks; and, on the next cycle, when the gripping blocks are opened, the portion of the tubing which is the desired capsule is released from its pair of gripping blocks and fed to a suitable receiver.

Abstract: The diameters of successive axial portions of an optical fiber being drawn are monitored and controlled by an optical measuring technique in such manner as to eliminate the effects of occasional, anomalous measurements or "dropouts". Measurement validity is tested by comparing, with a maximum allowable value, the difference between each successive diameter measurement and a standard for diameter measurement validity. Some examples of such a standard are provided. In addition, two embodiments of fiber monitoring systems are disclosed, as well as an overall monitoring and control system for fiber diameters.

Abstract: Method for reducing the likelihood of cathode ray tube glass bulb and bulb component fracture caused by temperature cycling during tube salvage. The depicted salvage method includes heating and then cooling the exterior surfaces of a glass front panel and glass funnel to be separated, thus producing a temperature gradient between the front panel extreme border and more remote inner portions of the front panel extreme border. This temperature gradient causes circumferential tension at the front panel extreme border. The circumferential tension is reduced to thus lessen, the likelihood of front panel fracture by applying, prior to or during, said cooling, a thermal insulator over the front panel extreme border and vicinity so as to locally reduce the rate of glass surface cooling.

Abstract: In the severing of bodies of glass or vitrocrystalline materials by the application of a laser beam, the severing operation is improved by employing a beam of which at least the predominent wavelength is such that at least 10% of the beam energy penetrates the body to a depth of at least 0.2 mm.

Abstract: In the severing of glass by irradiating it with a laser beam along the line where it is to be severed, the quality and speed of the severing operation are improved by preliminarily scoring the glass along such line.