Abstract: Bending and tempering of a glass sheet is achieved in that the glass sheet is submitted to the tempering phase while still being placed, as in the forming phase, on a forming ring integral with a frame which holds the latter, in order to maintain the previously formed shape unaltered. Vertical upward and downward movement is achieved both in the forming zone and in the glass sheet discharge zone by means of a rotating coupling device which supports the frame with forming ring and the glass sheet placed thereupon. Means are provided for conveying the frame with integral forming ring in the horizontal direction from the forming zone to the subsequent tempering and discharge zones, and other overlying similar means are provided to return the frame and forming ring from the discharge zone to the forming zone. A passageway or chamber is formed in the upper nozzle section of the tempering zone, through which may pass the frame and forming ring, as well as their horizontal driving members during the return traverse.

Abstract: A method for imparting increased mechanical strength to a glass object having imperfections in a surface thereof. The glass object is heated to a temperature above the strain point of the glass. A laser beam is generated having a wavelength absorbable by the glass and impinged on all portions of the surface containing the imperfections. The power density at which the beam is impinged is sufficient to rapidly heat a surface stratum of the glass to establish a thermal gradient therein whereby the viscosity at a depth from the surface sufficient to encompass the imperfections is low enough that the stress induced by the surface tension of the glass at the sites of the imperfections is sufficient to cause flow of glass and effect a reforming of the glass surface at said sites.

Abstract: Method and machine for making vials from glass tubing, wherein at least one glass tube (22) with closed bottom is loaded on a rotatable plate (11), having a series of holes circumferentially passing therethrough, and is then grasped by upper pliers (23'), provided on a plane not coincident with the rotatable plate (11), and then grasped by lower pliers (23) also provided on a horizontal plane not coincident with a lower rotatable plate (10), the tube (22) being continuously rotated on its axis by rotating elements of the pliers (23, 23'), and rotated throughout the circumference of the machine by rotation of the suitably controlled rotatable plates (10, 11). In this rotation the tube, as drawn or pulled at suitable intervals by the pliers, is caused to pass in front of a series of burners (17) arranged in suitable number on the entire periphery of the machine, such burners being provided with parabolic arc flames.

Abstract: Transferring rigid glass sheets from a first conveyor where the sheets are conveyed in end to end relation along a first conveyor through a first treatment apparatus where the sheets are suspended by tongs to a second conveyor where the sheets are conveyed in a broadside relation along a path parallel to and beyond the first conveyor. Such a conveyor system utilizes plant space efficiently.

Abstract: In a mold for shaping an apertured glass sheet comprising a shaping plate having a heat capacity more than that of the glass sheet per unit area and a shaping surface complementary to that desired for the glass sheet, areas having less heat capacity per unit area than that of the shaping plate are preferably obtained by cutting apertures in the shaping plate. These apertures or low heat capacity areas are located in the shaping plate in position to face corresponding apertures of the glass sheet to be shaped. When the shaping is performed by press bending the sheet between a pair of molds, preferably both press bending molds of press bending apparatus are apertured. The apertures or areas of low heat capacity in the molds are preferably slightly larger than the apertures in the glass sheet undergoing shaping to improve the stress pattern around the peripheral portion of the glass sheet apertures.

Abstract: The present invention relates to a special module for the entrance to a cooling station of a glass sheet tempering apparatus and particularly relates to the construction of a pair of upstream modules at the upstream end of the cooling station immediately beyond the exit of a furnace through which glass sheets are transported for heating for subsequent quenching and rapid cooling in order to impart a temper. The special entrance modules of the present invention are cooled by providing a baffle wall spaced upstream of the upstream wall of each upstream module that faces the furnace exit to provide an open ended air chamber between each upstream module and the furnace. In addition, optionally, coolant may be passed through pipe means provided between the furnace and the upstream modules. These changes in upstream module construction result in producing tempered glass with less kink than prior art apparatus having upstream modules not so modified.

Abstract: A method of and apparatus for press bending sheets into complex shapes including at least one press member of outline or ring-type construction having a plurality of shaping pads mounted within the outline of the shaping ring in combination with configurated conveyor rolls for preliminarily bending a heat-softened glass sheet prior to final bending into the ultimately desired configuration.

Abstract: When glass sheets are shaped by drop forming a glass sheet released from vacuum engagement against the bottom perforated plate of a vacuum platen to drop onto a shaping mold of ring-like construction, the intermediate portion of the glass sheet can develop excessive downward sag. The present invention discloses different techniques to develop an upward bow in the intermediate portion of the glass sheet sufficient to compensate approximately for the undesired excessive downward sag.

Abstract: Glass sheets arriving at a bending station where their under surfaces are exposed to a hot gas support bed are delivered with minimum misalignment and misorientation by engaging each sheet simultaneously across its entire width with at least two rotating conveyor rolls. The latter are spaced from one another longitudinally of a path of glass sheet travel a distance sufficient to optimize flow of hot gas against the engaged glass sheet surface. This invention enables the leading edge of glass sheets of either rectangular or non-rectangular outline to nest within aligning means located in a fixed but adjustable position at the bending station. Provision is made to handle two or more sheets arriving at the bending station in side-by-side relation.

Abstract: Glass sheets are shaped while heat-softened by engaging a surface thereof against an apertured surface of a vacuum mold within a heating furnace. After releasing the glass sheet for further processing, the vacuum mold is removed from the furnace without the glass sheet for cooling and returned to the furnace in sufficient time to engage the next glass sheet to be shaped. This invention avoids the need to overheat the glass to compensate for cooling that occurs when a mold engages a glass sheet outside a furnace to shape the latter without losing control of the maximum temperature to which the mold is subjected during a glass sheet shaping program.

Abstract: A method and apparatus are described for bending sheets in the plastic state, such as sheets of glass at their softening temperature, in two directions. The apparatus comprises a first bed of arcuate rods which can be positioned to impart a transverse curvature to the sheet and a second bed of arcuate rods which can be positioned to impart a longitudinal curvature to the sheet. Advantageously the bending is performed in a heated enclosure at a temperature at least equal to that at which the sheet is later tempered.

Abstract: A method for bending glass sheets is provided wherein glass is heated just to the softening point in a molten salt bath, then mechanically forced around a cylindrical or conical form using a forming member which hinges to follow the glass sheet onto the form, thereby maintaining the optical characteristics of the glass sheet by avoiding exertion of force along the plane of the glass sheet.The apparatus for use with the invention comprises a forming member which maintains contact with the part being formed at the same spot throughout the forming operation, means for supporting the part, and means for actuation.

Abstract: In press bending glass sheets delivered while heat-softened into a shaping station between an upper vacuum mold and a lower lifting mold wherein the glass sheet is first lifted on said lifting mold, transferred by suction to said vacuum mold, lifted while engaged by said vacuum mold to provide clearance for entry of a ring-like member to a position below said vacuum mold, stopping the suction in said vacuum mold to drop said glass sheet onto said ring-like member and removing said glass sheet from said shaping station while supported on said ring-like member, the rate of production is increased by lowering said vacuum mold into a parking position closely adjacent to the uppermost position permitted for said lifting mold to provide clearance for delivering a succeeding glass sheet to said shaping station and reducing the vertical distance needed to lift the glass sheet to a position where it can be transferred by suction to the vacuum mold once the ring-like member clears said shaping station.

Abstract: A glass sheet is suspended from a series of tongs which grip the upper margin of the sheet and apply individual forces at the gripping locations at least some of which have components acting out of the plane of the sheet. The magnitude and direction of each of said forces is selected to ensure that the suspended sheet, when at forming temperature, adapts towards a predetermined curved shape. The sheet may be bent with the forces acting at the gripping points before and/or after bending, and the sheet adopts the required curved shape when it is sufficiently stiffened to be influenced by the remanent forces applied at the gripping points.

Abstract: Sheet glass is heated during conveyance on a conveyor within a furnace. A vacuum holder is positioned within the furnace housing above the conveyor and has a downwardly facing surface with spaced openings in which a vacuum is drawn to receive a glass sheet from the conveyor and support the sheet above the conveyor. The holder surface is disclosed as being both planar and curved and as having a porous cover of ceramic fibers so as to distribute the vacuum and prevent marring of the glass as it is supported. Auxiliary lifters positioned between the rolls or vertical movement of the vacuum holder facilitates glass pickup. A carrier mold ring moves under the supported glass and the vacuum is then terminated so the glass drops onto the ring and bends under the bias of gravity in a manner that allows thin glass to be accurately bent. Subsequently the mold ring is moved from the furnace to a quench unit that temper the bent glass.

Abstract: Heat-softened glass sheets are shaped by being lifted by vacuum drawn through a platen and then dropped onto a shaping mold. The dropping of the glass sheets is assisted by rapidly replacing the vacuum in the platen with super-atmospheric pressure.

Abstract: Glass sheets are shaped while heat-softened by engaging a surface thereof against an apertured surface of a deformable vacuum mold and deforming the vacuum mold while maintaining the heat-softened glass sheet in vacuum engagement thereagainst.

Abstract: A method of prestressing at least one of the glass sheets of a sandwich safety glass, while being bent in a furnace, the glass sheet, after passing through a bending zone, being passed by a blow system and cooled by cooling air in the furnace in a temperature zone above the transformation point but below the deformation point of the glass, and an apparatus for such prestressing comprising a travelling die supporting superimposed sheets, a bending furnace zone to soften the sheets, and a cooling zone, the cooling zone having a blow system that subjects the bent sheet or sheets to cooling air.

Abstract: In shaping a pair of glass sheets simultaneously to a complicated shape including a longitudinal component of bend and a complicated transverse component of bend such as one that is S-shaped in elevation or other complicated shapes, the pair is sag bent in unison on an outline mold to sag bend the sheets to a shape approximating their longitudinal component of bend, then the pair of sag bent sheets is lifted on a solid mold having a complicated shape including said complicated transverse component of bend to impress said transverse component of bend (into engagement with an upper pressing mold of complementary curvature, if needed) and supported on said solid mold for the minimum time sufficient to develop said complicated shape.

Abstract: The invention relates to a fire-finishing machine for glass articles, of the type comprising a frame, a vertical rotary assembly mounted on the frame, drive means for ensuring the rotation of the vertical assembly which further comprises means for supporting article supporting cups intended to move over a circular path and burner holder means provided to follow the cups in their movement, wherein the supply of the burners is subjected to the action of adjustable means for opening and closing the flows of fuel so that the burners are adjusted once and for all in optimum manner and it is possible to vary the portion of path of the cups where fire-finishing takes place. The invention is more particularly applied to the manufacture of glass articles whose shape may or may not be of revolution.

Abstract: An energy saving method for the bending of glass sheets is disclosed. A sheet of glass is heated in an oven, conveyed to a curving form which includes a plurality of arched rods for imparting a desired curvature to the glass sheet, and finally the curved glass is tempered. The glass is heated in the oven to a first temperature that is only about 10.degree. C. greater than the required temperature of the glass at the commencement of the tempering step. Heat loss from the glass between the steps of heating and tempering is minimized by the disclosed apparatus which comprises a thermally insulating enclosure as well as means for cooling the rods.

Abstract: Heat-softened glass sheets are held by a flat vacuum platen and dropped onto a shaping mold to impart the desired curvature to the glass sheet.

Abstract: This invention covers shaping glass sheets to complicated shape by first preliminarily shaping said sheets to a prebent shape while supported on an outline mold, then completing the shape while cradling the prebent sheets within a thin flexible blanket of fiber glass cloth during final shaping by blow forming. This invention also covers a technique of cradling glass sheets in a flexible fiber glass blanket that is wrapped over the margin of the glass sheets to be shaped by blow forming. The margin of the blanket is reversely wrapped over a frame-like ring that prevents the marginal edge from curling and maintains the cradle in tension against the lower major surface of the glass sheet during shaping by blow forming.

Abstract: Heat softened glass sheets are held by a flat vacuum platen, portions of the glass sheet are pre-shaped by auxiliary shaping means while the glass sheet is being held, and then the glass sheet is dropped onto a shaping mold to impart the complete desired curvature to the glass sheet.

Abstract: In a drop forming process for shaping glass sheets, wherein a glass sheet is dropped from a flat vacuum platen onto a shaping mold, the final curvature of the glass is controlled by releasing a portion of the glass sheet from the platen prior to releasing the remainder of the glass sheet.

Abstract: Spacer elements affixed to the face of a flat vacuum platen induce a temporary reverse bow in a heat softened glass sheet held on the platen. The bowing is in the opposite direction from that of the final curvature, so that when the glass sheet is subsequently dropped onto a shaping mold the resulting sag in at least one direction is reduced.

Abstract: The flat glass sheet to be curved, which is at softening temperature, is advanced in a horizontal position on a curved bed formed by a series of flexible shaping rolls including coiled springs having progressively increasing degrees of curvature such that as the sheet moves thereon it will be caused to bend under its own weight to gradually assume the curvature of the shaping rolls. The shaping rolls are provided with end sections which are angularly adjustable to independently alter the degree of curvature of the rolls. The shaping bed is followed by a second bed formed of flexible rolls having a constant curvature on which the curved sheet is supported and subjected to a tempering and or cooling procedure. Means is also provided for driving the rolls of the shaping bed and the rolls of the second bed to move the glass sheets forwardly at a constant speed.

Abstract: A glass sheet is thermally treated, for example thermally toughened, by heating the glass sheet, and lowering the sheet into a gas-fluidized bed of particulate material which is at a glass-treatment temperature, for example quenching temperature. Extraction of gas from a localized upper region of the bed is commenced prior to the lowering of the hot glass sheet into the bed in order to produce gradually an unfluidized static packed condition of the material in that upper region of the bed. The glass sheet is lowered into the bed at a time after commencement of gas extraction which is such that the lower edge of the sheet passes through that upper region prior to full attainment of the static packed condition.

Abstract: In a method of heating a glass sheet which is moved on a conveyor which contacts one face of the sheet, anticlastic bending of the sheet is caused, and the stable anticlastic shape of the sheet is determined such that the sheet is arched away from the conveyor transversely of the sheet with respect to the conveying direction and with the sheet having a reverse curvature along its longitudinal extent so that the leading and trailing edges of the sheet are bent away from the conveyor. This reduces the contact between the contacted surface of each glass sheet and keeps the leading edge of each sheet clear of the conveyor. Anticlastic bending of the sheet is caused by producing a temperature differential between the central area and at least a part of the periphery of the sheet, for example, by heating said part of the periphery.

Abstract: An automatic system and process of shaping and tempering glass pieces comprising reception of a flow of heated glass pieces between upper transverse drive rollers and lower transverse drive rollers, driving and shaping the heated glass pieces between the upper rollers and lower rollers, circulating and deforming the glass pieces alternately between upper and lower positions of the upper and lower rollers, directing an air current upon the glass pieces at the moment the glass pieces circulate in the space between the upper and lower rollers, and discharging the shaped pieces from between the upper and lower rollers.

Abstract: In tempering glass sheets vertically hung from tongs, the uniformity with which tempering medium is applied toward the glass sheets during quenching is improved by providing the quenching apparatus with means to provide finer control of the flow rate of tempering medium against the opposite major surfaces of the glass sheets than one gets from valving branch conduits in order to prevent side-to-side swaying of the glass sheets during quenching, particularly when the sheets are curved. Such means to provide fine control is also useful in quenching glass sheets supported in other than vertical orientations during quenching.

Abstract: A glass sheet is thermally toughened by heating the sheet to a temperature near to its softening point and then lowering the sheet into a gas-fluidized bed of particulate material. A void region is established beneath the lower edge of the sheet as it is initially immersed in the fluidized bed.

Abstract: Glass sheets are brought into accurate alignment with bending means while horizontally disposed by urging the glass sheets into contact with a contoured line of abutment. Some embodiments permit simultaneous aligning of a plurality of glass sheets side-by-side.

Abstract: Apparatus and a method disclosed for use in bending heated sheets of glass (G) transported generally horizontally on a conveyor (16) within a furnace heating chamber incorporate a holder (20) located above the conveyor in a spaced relationship such that a heated sheet of glass can be transported under the holder. Gas such as air is blown upwardly from below the conveyor against the heated sheet of glass such that the sheet is moved upwardly into engagement with the holder. The upwardly blown gas is provided by an array of gas jet pumps (60) positioned below the conveyor. A mold ring (44) is then movable under the holder to receive the glass sheet for bending. Holder (20) is disclosed as including curved and planar surfaces and as including curved and planar rings. A vacuum may be drawn with the holder embodiments having the surfaces so as to assist the upwardly blown gas in lifting the sheet of glass off the conveyor.

Abstract: A system (10) and method disclosed for use in bending glass incorporate a vacuum holder (12) having a surface (28) with spaced openings (32) in which a vacuum is drawn to support a heated sheet of glass (G) and in which pressurized gas is subsequently supplied to force the glass sheet away from the holder surface. In one embodiment, operation of a control damper (24) initially communicates a vacuum blower (20) with the holder and subsequently communicates a positive pressure air blower (22) therewith to first draw the vacuum and then supply the pressurized air to the openings in the surface which is disclosed facing downwardly. During an intermediate step, the damper is positioned so that a reduced vacuum is drawn to prevent deformation of the heated glass sheet at the spaced openings in the holder surface. In an alternative embodiment, a gas jet pump (90) is used to produce the positive and vacuum pressures used in the practice of the invention.

Abstract: An apparatus and method for tempering glass is described. Glass sheets are passed through a tempering furnace along a predetermined generally horizontal path. The temperature of the sheets is measured by a pivoting pyrometer above the sheets and the furnace is regulated to achieve a zero temperature profile across the plates.

Abstract: This invention relates to the handling of glass sheets that are supported by a conveyor along their bottom edges and balanced in an upright position for movement through a furnace, a shaping station and a cooling area. Means are provided to temporarily lift the glass sheet so that its entire extent is aligned with the facing shaping surfaces of a pair of shaping molds during shaping and returned to the bottom edge supporting conveyor which conveys the shaped glass sheet into the cooling area after it is shaped. Such treatment improves the contour of the bottom edge of the shaped glass sheet.

Abstract: An untempered sheet of glass is given a predetermined curvature by means of pre-heated forming dies (3,4 in FIG. 1). The glass sheet (1) is not pre-heated or is heated only to a relatively low temperature prior to being inserted between the dies. Heat transfer from the dies to the glass prior to closure of the dies produces or assists in producing in the thickness of the glass sheet a transitory thermal stress gradient which gives resistance to breakage under bending forces. The absence of high temperature pre-heating of the sheet is conducive to a more predictable stress distribution pattern over the area of the sheet prior to bending. The process enables predetermined sheet curvatures to be achieved with higher degrees of accuracy.

Abstract: A method of treating a silicon single crystal ingot which comprises the steps of purposely producing lattice strains in a silicon single crystal ingot, annealing the ingot at high temperature, and etching off the surface of the annealed ingot, thereby suppressing the occurrence of lattice defects.

Abstract: This invention relates to improvements in handling glass sheets during shaping and cooling. Each glass sheet in turn is heated to its deformation temperature and conveyed into a glass shaping station. The glass is lifted into engagement with an upper vacuum shaping mold while hot and held against the vacuum shaping mold by vacuum as the glass lifting mechanism retracts downward. A transfer and tempering ring-like member having stop means upstream of an outline supporting surface conforming to and slightly inside the periphery of the bent glass sheet is brought into a position where its stop means are slightly misaligned upstream of the trailing edge of the glass sheet. The vacuum on the upper mold is released to deposit the shaped glass sheet on the ring-like member.

Abstract: This invention relates to a movable gate disposed between a fluid application station and a glass sheet transfer station of apparatus for processing heated glass sheets that are suspended or gripped by tongs along their upper edges during their conveyance along a first path of glass sheet travel for heating and further processing. The gate is moved to a retracted position to let a glass sheet leave the fluid application station and into an operative position to minimize swaying of the processed glass sheet when the latter is along said first path of glass sheet travel downstream of said fluid application station. This increases the chance of transferring the glass sheet in non-tilting relation to a peg conveyor located along a second path of glass sheet travel.

Abstract: A method of thermally toughening a glass sheet in which the glass sheet is advanced through a quenching station and subjected to a localized gas flow. The localized gas flow is pulsed at a repetition frequency related to the speed of advance of the glass through the quenching station. The toughened glass sheet so produced has a distribution of regions of more highly toughened glass interspersed with regions of lesser toughened glass.

Abstract: A method of thermally toughening a glass sheet in which the glass sheet is advanced into a flow of quenching gas directed towards at least one surface of the sheet to induce overall toughening stress in the glass sheet. The advance of the sheet relative to the quenching gas flow is terminated, either by halting the sheet in the flow or by moving the outlets providing the flow with the sheet, so that at least one surface of the sheet is subjected to localized gas flows. The toughened glass sheet so produced has a distribution of regions of more highly toughened glass interspersed with regions of lesser toughened glass.

Abstract: The edge portion of a plate glass is locally heated to a temperature higher than that in the other portion of the plate glass, after the whole of the plate glass is heated. Electric current is thereafter applied to the edge portion of the plate glass in order to further heat the edge portion so that the edge of the plate glass is slightly melted.

Abstract: In tempering glass sheets vertically hung from tongs, the uniformity with which tempering medium is applied onto the glass sheets during quenching is improved by providing the quenching apparatus with a plurality of discs carried on wires on one side of the path taken by glass sheets through the quenching apparatus. The flow of tempering medium is controlled so as to force the glass sheets against the discs, thereby avoiding uncontrolled buffeting of the glass sheets during quenching. The discs are designed to minimize interference with the flow of tempering medium and preferably include openings through which the tempering medium may flow, such as serrations along the edges.

Abstract: This invention relates to refinements in operating apparatus for tempering flat or curved glass sheets suspended in a vertical orientation comprising a plurality of nozzle boxes each pivotable about its longitudinal axis and adjustable in position to provide a pair of sets of nozzle boxes facing the opposite major surfaces of a glass sheet held in a quenching position between two sets of nozzle boxes. The present invention provides minimum buffeting of the glass sheets while applying tempering fluid against the opposite major glass sheet surfaces, while avoiding iridescent patterns in the tempered glass.Each set of nozzle boxes is pivoted in unison out of phase with the pivoting of the other set of nozzle boxes by a phase difference of 75 to 105 degrees, preferably approximately 90 degrees. The number of pivoting cycles is controlled to between 25 and 40 cycles per minute, and preferably approximates 30 cycles per minute.

Abstract: The efficiency of tempering flat or curved glass sheets suspended in a vertical orientation is improved in the type of quenching operation wherein quenching nozzles are arranged on a plurality of nozzle boxes, each of which is pivotable about its longitudinal axis so as to oscillate the nozzles in unison within planes which are parallel to each other. The improvement here achieves optimum heat exchange, with a minimized amount of power consumption for supplying pressurized tempering fluid, by controlling the angular displacement of the oscillating nozzles within an angle of 20 degrees from normal to the portion of the glass sheet surface opposite each respective nozzle.

Abstract: Heat-softened glass sheets are shaped to either simple or compound bends while being continuously conveyed by means of forming rolls having transverse curvature, wherein, in at least the first portion of the bending station, the force of gravity alone causes the glass sheets to sag into substantial conformity with the transverse curvature of the forming rolls. Support for each glass sheet is gradually transferred from straight conveyor rolls to curved forming rolls without vertically reciprocating the rolls. Optionally, at the exit end of the forming station, a set of upper forming rolls having transverse curvature complementary to that of the lower forming rolls may be provided to assure close conformance to the desired curvature. Compound bends may be formed by providing the path defined by the lower forming rolls with a concave curvature in the direction of glass travel.

Abstract: A transfer apparatus in a glass heat treating operation for removing a horizontally disposed sheet from a horizontal glass processing line and reorienting it into a substantially vertical plane for final processing in a vertically oriented quench operation. The transfer apparatus constitutes a pivotal end section of a horizontal conveyor system and is adapted to be equipped with glass bending fixtures.

Abstract: A method of fabricating bent laminated safety glass windshields having at least one hole through the entire thickness thereof adjacent to but spaced entirely from the marginal edge thereof is disclosed.