Abstract: The present invention provides a manufacturing method of a sheet glass material excellent in flatness. A manufacturing method of glass substrate for magnetic disk including a pair of principal surfaces, the method comprising the steps of: dropping process for dropping a lump of molten glass; pressing process for forming a sheet glass material by performing press forming to the lump while sandwiching the lump from both sides of the dropping path of the lump with facing surfaces of a pair of dies, the pair of dies being set to substantially the same temperature; and processing process for processing the sheet glass material, while the lump drops down while revolving around its dropping axis.

Abstract: To provide a method for cutting a glass material wherein the glass material can be certainly cut a glass gob having a uniform quality and a uniform temperature distribution, without being deformed or damaged. Upon cutting a glass material 20 discharged from a glass material reservoir 10 into a glass gob 21 at a predetermined size by left and right cutting blades 91, 92 which come close to or away from each other in a horizontal direction, said cutting blades 91, 92 are opposed to the other and are translated in such a way that the movement occurs in a forward direction from stand-by positions P, P1 and in a downward direction (S1) to cut the glass material (C), and thereafter, in a further downward direction and in a rearward direction (S2), and thereafter, in an upward direction to return back to said stand-by positions (S3).

Abstract: A plate-shaped shearing knife is provided made of hard metal for shearing off allotments of liquid glass. The hard metal of the shearing knife has a thermal conductivity of at least 85 W/mK. Next to a V-shaped or circular-shaped cutting region -2-, there are edge regions on both sides that do not flare out wedge-like, and have an average width b which is in a range of 5% to 30% of the total width of the shearing knife B in this section.

Abstract: A plate-shaped shearing knife is provided made of hard metal for shearing off allotments of liquid glass. The hard metal of the shearing knife has a thermal conductivity of at least 85 W/mK. Next to a V-shaped or circular-shaped cutting region -2-, there are edge regions on both sides that do not flare out wedge-like, and have an average width b which is in a range of 5% to 30% of the total width of the shearing knife B in this section.

Abstract: In an apparatus (1) for the severing of gobs from one or more strands (2;3) of molten glass, the severing of each gob is effected by a shear blade pair (5;6). A shear blade (7,8;9,10) of each shear blade pair is arranged on an associated, pivotably mounted shear arm (11;12). The two shear arms (11;12) are coaxially and freely pivotably mounted relative to each other on a common column (13). Each shear arm is pivotably drivable synchronously in relation to the other by its own separate drive means (24;25).

Abstract: An excellent quartz glass optical member having stable laser beam resistance, can be obtained by preparing quartz glass in a process having:a first step of subjecting a starting material obtained from silicon halide, alkoxysilane, alkylalkoxysilane, etc. to an oxidizing heat treatment in a temperature range between 600 and 1,500.degree. C., to decrease the hydrogen concentration to 5.times.10.sup.16 molecules/cm.sup.3 or less and at the same time eliminate reducing defects;a second step of subsequently holding the quartz in a hydrogen-containing atmosphere in a temperature range between 200 and 600.degree. C., to establish a hydrogen concentration in the glass of 1.times.10.sup.17 molecules/cm.sup.3 ; anda third step of carrying out a treatment of making the hydrogen concentration of the resultant quartz glass uniform in an atmosphere of air, inert gas, hydrogen, a mixture of hydrogen and inert gas, or a mixture of air and inert gas in a temperature range between 300 and 800.degree. C.

Abstract: A laser surface method involves applying a laser beam treatment in one or several steps to a series of generally similar surfaces of given depth. Properties of the laser treatment are selected so as to change the physical state of each surface. Ellipsometry measurements are made in a region of the first surface before application of the laser beam treatment to the second surface, so as to obtain a physico-chemical characterization of the first surface. Both the laser beam application and the ellipsometry measurement are conducted under generally similar working conditions, so that the change of the physical state of each surface produced by the laser treatment can be controlled in a real time, in-situ, rapidly and nondestructively.

Abstract: The present invention provides a process for substantially extending the useful life of fused silica elements used in high energy ultraviolet optical systems. The fused silica bulk material is pre-compacted by illuminating it with radiation prior to final mechanical fabrication and polishing to the required final surface figure. When the optical element is subsequently used in a high energy ultraviolet environment, it will continue to be compacted but at a lower effective rate. As a result, the useful life of fused silica optical elements can be increased substantially.In preferred embodiments the fused silica material is precompacted with multiple passes of short-pulse ultraviolet radiation. Multiple passes can reduce precompaction time. In one example useful life of the fused silica is increased from about 150 days to 3.8 years by about 5 days of precompaction.

Abstract: A unitary shear blade (20) for shearing a plurality of spaced apart streams of molten glass into individual gobs, the shear blade having a free end (20a) and an opposed end (20b). The free end is provided with a plurality of side-by-side shearing surfaces (22, 24, 26) each of which has a generally V-shaped machined shearing edge. A plurality of fastener receiving openings (28) extends through the shear blade at locations adjacent the opposed ends thereof to permit the shear blade to be removably secured to a carriage (10) by a plurality of threaded fasteners (12).

Abstract: A parallel shear apparatus (20) for simultaneously shearing a plurality of streams of molten glass (A, B, C) into gobs comprising opposed carriages (22, 24) which are repetitively moved along rectilinear opposed paths toward and away from one another by a unidirectionally acting servo motor/gear reducer (44) acting through an oscillating bell crank (30). Each of the carriages carries a plurality of shear blades (40a, 40b, 40c/42a, 42b, 42c) which cooperate with one another to shear the glass streams into gobs when the carriages are positioned close to one another. The shear blades carried by each of the carriages have internal flow passages (66) to permit the blades to be internally liquid cooled by liquid entering the carriages from inlet lines (52, 56), and the blades carried by one of the carriages (22) are biased by compression springs (82) into contact with the blades carried by the other carriage (24) to prevent excessive contact loads between the blades in their shearing positions.

Abstract: The present invention provides a method for manufacturing an optical component that have increased transmittance in the ultraviolet region of the spectrum. The method includes the steps of cutting out a part from a block material; polishing optical sides of the part; subjecting the part to heat treatment at a temperature of between 100 and 900.degree. C.; and subjecting the part to acid treatment.

Abstract: A process of manufacturing a silica glass article comprising the steps of: (1) irradiating a silica glass article with electromagnetic waves to generate defects therein; and (2) immersing the thus irradiated silica glass article in an atmosphere comprising a hydrogen gas, thereby providing the resulting silica glass article with a characteristic that is effective for preventing it substantially from increasing its absorption within an ultraviolet region due to ultraviolet ray irradiation. Also disclosed are a silica glass article or a glass fiber produced according to the manufacturing process.

Abstract: An optical micro-machining method of glass characterized in that after light is applied to glass including SiO.sub.2 and 30-70 mol % GeO.sub.2, the irradiated area is removed by etching.

Abstract: A parallel shear apparatus (20) for simultaneously shearing a plurality of streams of molten glass (A, B, C) into gobs including opposed carriages (22, 24) which are repetitively moved along rectilinear opposed paths toward and away from one another. Each of the carriages carries a plurality of shear blades (40a, 40b, 40c/42a, 42b, 42c) which cooperate with one another to shear the glass streams into gobs when the carriages are positioned close to one another. The shear blades carried by each of the carriages have internal flow passages (66) to permit the blades to be internally liquid cooled by liquid entering the carriages from inlet lines (52, 56), and the blades carried by one of the carriages (22) are biased by compression springs (82) into contact with the blades carried by the other carriage (24) to prevent excessive contact loads between the blades in their shearing positions. A contact lubricator (88) is provided to lubricate the contact surfaces of the blades carried by one of the carriages (22).

Abstract: A parallel shear apparatus (20) for simultaneously shearing a plurality of streams of molten glass (A, B, C) into gobs comprising opposed carriages (22, 24) which are repetitively moved along rectilinear opposed paths toward and away from one another. Each of the carriages carries a plurality of shear blades (40a, 40b, 40c/42a, 42b, 42c) which cooperate with one another to shear the glass streams into gobs when the carriages are positioned close to one another. The shear blades carried by each of the carriages have internal flow passages (66) to permit the blades to be internally liquid cooled by liquid entering the carriages from inlet lines (52, 56), and the blades carried by one of the carriages (22) are biased by compression springs (82) into contact with the blades carried by the other carriage (24) to prevent excessive contact loads between the blades in their shearing positions.

Abstract: Converged laser beam are irradiated, at right angles, to the surface of a workpiece which is made of glass and supported in a horizontal posture, so that the surface of the workpiece is locally heated and melted. The surface of the workpiece is formed into a convexly curved surface under the effect of surface tension occurrable to the glass material at the time the surface of the workpiece is melted. By hardening the workpiece, a micro lens having the convexly curved surface is formed.

Abstract: Glass ceramic for use as a biomaterial comprising CaO 34.6 to 54.6%, SiO.sub.2 24.2 to 44.8 %, P.sub.2 O.sub.5 0 to 8.0%, CaF.sub.2 0.1 to 1.0% and Mgo 1.0 to 10.0% by weight and characterized by a primary wollastonite crystalline phase (CaO, SiO.sub.2) and a secondary apatite crystalline phase, and the process for the preparation thereof are disclosed. The glass ceramic of the present invention has superior mechanical properties, good biocompatibility, bioactivity, and no toxicity making it useful as a biomaterial in artificial bone and dental implants.

Abstract: Optical waveguides are produced in laser densified Type VI porous gel-silica. A CO.sub.2 laser directly scans the substrate having a pore size of about 30 angstroms. Tracks having a width of about 50 microns are produced.

Abstract: A surface of a ceramic article, such as a glazed surface on a whiteware article, is treated with radiant energy such as infrared light from a laser to provide a localized remelting of the material at the surface in a fusing step. After the fusing step, the surface is treated with further radiant energy, desirably over a larger surface encompassing the fused zone and also desirably at a lower power density so as to limit the rate of cooling of the fusion zone and the immediately surrounding regions, thereby preventing thermal stress cracking. The fusion zone and surrounding regions desirably are preheated by additional radiant energy immediately prior to the fusing step so as to further limit thermal stresses during the fusing step. The process can be employed, among many other uses, for repair of glaze defects and for decoration.

Abstract: A method and apparatus for continuously producing an endless thermoplastic material, such as yarn or tape, and winding the material into a package. A physical parameter of the package, such as its diameter or weight, is monitored, and a control signal is generated which is a function of the monitored physical parameter. The control signal is then compared to a predetermined reference signal, and an output signal is generated when the difference between the control signal and the reference signal exceeds a predetermined deviation. The output signal thus represents the quality of the material in the package, and it may be used to permit classification of the final product or to control the operating conditions of the apparatus so as to maintain a desired quality level.

Abstract: A method of processing a photosensitive glass includes exposing. Photosensitive glass by radiation from a laser whose oscillation wavelength lies within the range of wavelengths of exposing light to which the glass responds. Then, the exposed portions 1c are thermally developed and etched. Since a laser beam propagates with a high rectilinearity, the front and rear surfaces of thick photosensitive glass can be exposed without producing dimensional errors. Therefore, the etching accuracy is improved. Especially, where the front and rear surfaces of photosensitive glass are etched, both surfaces can be processed so as to form the same shape in them accurately. In addition, because almost all the energy of the laser radiation is used for exposure of the photosensitive glass, the energy is not wasted and so the efficiency is high.

Abstract: At least a pair of shear blades cuts a stream of viscous molten glass descending from a glass feeder. The paired shear blades continuously move, while retaining a substantially horizontal position, about a horizontal axis along looped paths symmetrical to each other on opposite sides of the descending stream of molten glass. When viewed in a vertical plane, each loop represents the forward motion of each blade toward the center of the descending stream of molten glass, the crossing of the cutting edges provided on the two facing blades, and the retreat of each blade away from the center of the glass stream. The cutting of glass stream begins at the end of the forward motion of the shear blades and ends when the cutting edges provided on them have crossed each other. This permits the area and time of contact between the shear blades and the descending stream of molten glass to be minimized.

Abstract: A shear mechanism has opposed shear assemblies mounted for reciprocation on a pair of parallel guide rails. Each shear assembly has a removable portion which supports the shears with top accessible fasteners so that these portions can be removed when the shear assemblies are fully advanced. A stop mechanism locks the shear assemblies at their fully advanced positions.

Abstract: A shear mechanism has a shear assembly with shear assembly that can be quickly changed. The shear assembly supports a vertically displacable shear which is operated via a drive system which is connected to the shear mechanism frame. With the release of top fasteners which secure the shear assembly to the guide rail support and the release of a top accessible support bearing the shear assembly can be lifted out of the frame since the shear drive system and shear assembly are vertically separable.

Abstract: Shears are supported for reciprocating displacement within an open frame so that they can be conjointly displaced from retracted positions to advanced overlapping positions where a runner of molten glass will be severed. A pair of covers close the open frame except for the central portion where the runners pass through. A pipe having a plurality of holes is secured to the front edge of the covers so that coolant can be directed downwardly and inwardly against the reciprocating shears.

Abstract: Each glass gob is severed by a shear blade pair (6; 9). The shear blades (7, 8; 10, 11) are arranged on shear arms (12, 13) whose movement is synchronized with each other by means of a gear mechanism (16) A first shear arm (12) is drivable pivotably by a drive means (36), while a second shear arm (13) is supported by an air spring (28). The drive means (36) is carried on a carriage (39) which is displaceable by piston-cylinder units (48, 49). The drive means (36) drives a crank pin (43) which is connected by means of a coupling rod (44) with the first shear arm (12). By displacement of the carriage (39) one achieves a servicing stroke (34) which is greater than the working stroke (32) of the shears.

Abstract: A shear mechanism has a pair of shear assemblies mounted on parallel guide rails for reciprocating displacement controlled by a rack and pinion assembly having a rack driving each shear assembly. The racks are parallel and horizontally spaced and their movement paths substantially intersect the center of mass of the shear assemblies.

Abstract: A glass gob cutting device in a gob feeder for cutting a gob of molten glass supplied from an orifice of a furnace and supplying the cut gob of molten glass to a glass forming machine. The glass gob cutting device includes a pair of shearing blades for cutting a gob of molten glass to make the cut gob of molten glass, a pair of supporting arms for supporting the pair of shearing blades, a shearing mechanism connected to the supporting arms for actuating the supporting arms, a guide arm being actuated by actuating means different from the shearing mechanism and a guide provided on a free end of the guide arm for guiding the cut gob of molten glass and introducing the same into the glass forming machine.

Abstract: On shearing a melted glass stream flowing along a first direction at a first speed into a melted glass lump flowing along the first direction at a second speed faster than the first speed by a cutter section, the cutter section is closed and opened along the first direction and is also moved in a second direction substantially perpendicular to the first direction. While the cutter section is moved in the second direction, the motion of the cutter section is controlled at a third speed between the first speed and the second speed.

Abstract: A straight line shear mechanism has rack driven shears which are operated by a pneumatic cylinder. Opposite ends of the operating rod of the pneumatic cylinder are connected via nail head couplings which permit rotation of the rod about its axis and which automatically accommodates slight misalignments to minimize distortion of the rod.

Abstract: A straight line shear mechanism has rack driven shears which are operated by a pneumatic cylinder. The shear slides provide a barrier to infrared energy directed at the pneumatic cylinder. To cool the cylinder, a perforated cooling tube is connected to ambient air when the mechanism is operating and is connected to water when the mechanism is not operating.

Abstract: A molten glass feeder includes a feeder bowl and a rotating refractory tube. Molten glass is discharged through openings in an orifice plate which are controlled by vertically displaceable needles. To reduce heat loss through the refractory tube, a heat shield is provided which is made up of two mirror imaged parts. Each part has a semicylindrical pan having a lip at the bottom for supporting a semi-circular support plate. Located on this plate is an insulation retainer which has a semi-circular base and a vertical wall at its diameter. This wall forms an insulation receiving bin with the pan.

Abstract: An improved drive assembly for a straight line shear mechanism or like, reciprocably mounted mechanism of a glassware forming machine wherein the mechanism is coupled by an arm to a drive rod, the improvement lying in the provision of an adaptable joint between the drive rod and the arm. Such joint permits a limited amount of radial repositioning of the arm relative to the drive rod, and a lesser amount of axial repositioning and reorientation. A preferred design of such joint utilizes a hardened sleeve fitted around a segment of the drive rod, such sleeve having a flange to provide a radial surface. A rod nut placed at the other end of the sleeve provides a second radial surface. A bushing secured within an aperture of the arm by a bushing nut is housed around the sleeve between the sleeve flange and the rod nut.

Abstract: This relates to improvements in drives for shears, particularly shears for severing gobs from a glass runner. All of the drives incorporate a drive pinion for reciprocating racks which are secured to slides of the shear. The pinion is rotated first in one direction and then in the opposite direction to cause the blades of the shear to first move together and shear a gob, and then move back to the original position. Suitable reversing motors may be utilized, including an electrical servomotor or suitable hydraulic motor. On the other hand, the drive motor may be of the unidirectional type and an oscillating drive member may be incorporated in the drive system for converting the one-directional drive of the motor to an oscillating or reversing output. In addition, the drive of the pinion may be supplemented by a double-acting air motor which is connected to one of the racks.

Abstract: The apparatus comprises two horizontally extending blades (22, 24) mounted for turning movement about a common vertical axis (26). The blades each have a hole (28; 30) therein so arranged that, when the blades are in a first condition, the holes are aligned and a vertical column of plastic material (12) can pass through the holes. Upon the blades being turned about the common vertical axis through a predetermined angle, one clockwise and the other anti-clockwise, edges of the holes (28; 30) pass each other until the holes do not overlap and the column of plastic material passing through the holes is sheared through by edges of the holes.

Abstract: A swing out support frame is provided on X-Y slide support structure such that one of several different diameter refractory tubes can be supported in a fixed spout bowl for rotation inside the bowl, and also for electrically controlled and non-electrically dependent vertical movement of the tube inside the bowl.

Abstract: The feeder mechanism comprises apparatus for shearing gobs from plastic material e.g. glass comprising a set of shear blades movable between open and shearing positions thereof. A driving system for the shear blades comprises a cam having a cam track and a servo-motor arranged to drive the cam at a speed which is varied in accordance with control signals derived from a stored program to move the shear blades in accordance with a desired position against time curve between limits defined by the shape of the cam track.

Abstract: The invention relates to a cutting device for the sectioning of a liquid glass strand into individual fragment (gobs) to be further processed into hollow glass articles. In order to achieve a trouble-free cutting process as well as a relatively small mass of the parts moved during the cutting, combined with an increase in the production rate, the invention proposes a cutting device having a housing (2) in which a cutting unit (3) is formed by several partially overlapping cutting elements (4) disposed around the glass strand (5) which are rotatably journaled at one of their ends and connected to the planet gears 7 of a planetary gearing whose outer ring gear (8) is connected with a drive. The cutting edges of the cutting elements (4) are of curved shape.

Abstract: A feeding device has the object to ensure the supply of a continuously flowing glass strand and to divide it into predetermined gobs thus establishing the weight of the individual gob and thereafter to proceed with the final sectioning. It is known to activate the drives of the moving mechanical parts of such a feeding device by compressed air. Because of the compressibility of the air, and depending, among others, on the length of the piping, its clear cross section and the prevailing air pressure, an accurate control is not possible, especially when the masses to be moved are large. In order to avoid these disadvantages, the invention makes use of hydraulic piston units for the drive of the translatory movement of the stopper and of the pipe and the use of a hydraulic rotary piston for the rotational movement of the cutting device. The turning movement of the pipe is achieved through a hydraulic rotary piston.

Abstract: In a glass molding machine, for example, of the type known in the industry as I.S. machines, an apparatus for shearing molten glass into gobs as the glass issues from a feeder includes mechanisms for independently adjusting both the horizontal and vertical position of the shears with respect to the feeder nozzles, as well as the distance between the two halves of the shear blades and the length and time duration of the cutting stroke. All adjustments are possible without shutting down the entire forming operation and can be effected merely by supplying energy to adjusting motors.

Abstract: A glass article such as a sham bottom tumbler with a decorative air bubble encapsulated in its base is produced on existing automatic glass-forming machines by injecting a bubble of air into a charge of molten glass in the gob-feeder section of a glass furnace as the charge is being formed into a gob. This is accomplished by mounting an air supply pipe in the gob-feeder orifice. Preferably, the outlet end of the pipe extends radially to the center of the orifice. Puffs of compressed air are supplied in synchronism with the feeder plunger cycle so an air bubble is formed in the lower end of the gob, and the gob is then formed by normal procedures into a finished article.

Abstract: A glass article such as a sham bottom tumbler with decorative air bubble encapsulated in its base is produced on existing automatic glass-forming machines by injecting a bubble of air into a charge of molten glass in the gob-forming section of a glass furnace as the charge is being formed into a gob. This is accomplished by providing an air supply tube in the gob-forming plunger. Preferably, the lower tip of the tube extends below the lower tip of the plunger. Puffs of compressed air are supplied in synchronism with the plunger cycle so an air bubble is formed in the lower end of the gob, and the gob is then formed by normal procedures into a finished article.

Abstract: According to the first method according to the present invention, there is provided a method for manufacturing glass products by casting low viscosity glass into a mould while controlling free flow of the glass by storing and holding the glass continuously fed out of a feeder outlet in a region under the lower surface of a control member provided below the feeder outlet after a cutting step, whereby the operation for setting a next mould to receive the glass in position is facilitated, the shape of the flowing glass after cutting is made stable and homogeneous gob can be produced.