Abstract: A blow box for the thermal tempering of panes of glass. To temper different sizes of glass, the air supply to selected blow tubes or blow tube groups in a blow box having a blow nozzle field disposed to handle relatively large panes of glass is blocked in the edge areas of the blow box, and in this manner the blow nozzle field supplied with forced air is adapted to the shape and size of the glass pane to be tempered. The adaptation of the blow nozzle field to the shape and size of the glass panes takes place, for example, with the aid of a template-like slide block having an opening corresponding to the glass pane, which slide block is arranged inside the air distributing box immediately in front of the front plate provided with the nozzle pipelets and which can be exchanged for a different slide block.

Abstract: Compression stresses are formed on the periphery of a glass sheet by blowing cooling air on the periphery of the heated glass sheet. The cooling air is blown by using a pyramidal deflector to deflect air flow radially outward toward the edges of the glass sheet. By adjusting the spacing between the deflector and the glass sheet, the size of a central, relatively quiescent, zone can be adjusted. The air flow is provided by a duct which can include a pyramidal skirt which surrounds the deflector to form a gas flow path whose size controls the cooling rate. Pyramidal flaps within the gas flow path can be used for adjusting cooling gas pressures.

Abstract: A blow box for thermal tempering of panes of glass is disclosed. To temper different sizes of glass, the air supply to selected blow tubes or blow tube groups in a blow box having a blow nozzle field disposed to handle relatively large panes of glass is blocked in the edge areas of the blow box. In this manner, the blow nozzle field supplied with forced air is adapted to the shape and size of the glass pane to be tempered. The adaptation of the blow nozzle field to the shape and size of the glass panes takes place, for example, with the aid of a template-like slide block having an opening corresponding to the glass pane, which slide block is arranged inside the air distributing box immediately in front of the front plate provided with the nozzle pipelets and which can be exchanged for a different slide block.

Abstract: In a glass tempering system (11) a blow back control device (10) disclosed includes a housing (24) having a pair of housing portions (34) defining a pair of suction chambers (26) mounted above an exit opening (20) of a glass heating furnace (12). Housing (24) has a slot (32) including slot portions (36) extending along and opening into suction chambers (26). Blowers (30) are connected to each suction chamber (26) for drawing spent cooling gas into suction chambers (26) through slot portions (36) and for discharging the gas away from exit opening (20) of furnace (12) to avoid temperature swings in the furnace caused by cooling gas entering the furnace.

Abstract: The invention relates to air tempering of glass in flat tempering installations. It proposes blowing air, particularly at sonic speed, with nozzles, preferably tubular, slightly distant from the glass, exhibiting the maximum loss of pressure at their free end close to the glass. It makes possible the tempering, under economically advantageous conditions, of glass sheets having thicknesses less than 2 mm and all the more so, glass sheets having greater thicknesses, which can be used as glasses, particularly windshields, for motor vehicles.

Abstract: The invention relates to a flow barrier in the annealing section of a glass tempering apparatus, said annealing section being provided with glass sheet supporting rollers (7) and cooling air blow boxes (1, 3) are disposed above and below a glass sheet, in addition to which there are, above the glass sheets, "false rolls" (8) in the form of a downward open trough, extending crosswise to the traveling direction of said glass sheets. The purpose of "false rolls" (8) is to increase a pressure applied to the top surface of a glass sheet in order to reduce the risk of a glass sheet becoming afloat. A flow along the trough, which increases towards the ends of the trough, results in a non-uniform tempering. The flow is cut off by fitting the trough with partitions (9) spaced from each other.

Abstract: The roller cleaning apparatus of the present invention includes a frame which has a pair of caster mounted wheels located at one of its ends. The casters are connected to one another through a tie-rod which causes them to turn as a unit between a right-hand facing orientation and a left-hand facing orientation. The wheels have a diameter which permits them to span an adjacent pair of the rollers which are to be cleaned. Thus, if the rollers are rotating the apparatus translates across the rollers toward the right when the casters are in their right-hand orientation and toward the left when the casters are in their left-hand orientation. A spring normally urges the casters to their right-hand orientation, however, a latch mechanism locks them in their left-hand orientation when they are manually placed there. The latch mechanism has a release device which automatically releases it when the apparatus reaches the left-hand side of the rollers.

Abstract: A method of producing heat strengthened glass in which the glass is heated to a temperature above its strain point and is then cooled while horizontally supported. Discontinuous support is provided for the glass as it is cooled by intermittent regional contact with the lower surface of the glass, whereby any pattern of iridescence resulting from heat transfer between the lower glass surface and the support is free of prominent continuous features. A glass treatment furnace for producing heat strengthened glass, has horizontal glass-supporting rollers and cooling-flow supply means in the vicinity of those rollers, the bearing surface of each roller comprising discontinuous bearing elements which provide intermittent regional support contact with the lower surface of the glass.

Abstract: In glass tempering using a cooling gas, the impact of gas jets on glass is modified through the use of perturbations to which said jets are subject. The perturbations may be introduced laterally with respect to the tempering jets, and spaced from the opening providing said tempering jets. The characteristics of the perturbations vary cyclically. The invention makes it possible to obtain homogeneous tempering, even for highly bulged glass sheets.

Abstract: A ring mold unit for shaping and tempering a glass sheet includes a shaping ring mold for bending a glass sheet heated to a temperature close to the softening point of glass, in association with upper and lower mold members, and a cooling ring mold for supporting the bent glass sheet while the glass sheet is being quenched and tempered by a cooling medium. The shaping ring mold has a thermally insulating member on its upper surface for supporting thereon, in surface-to-surface contact, the glass sheet inwardly of a peripheral edge thereof. The cooling ring mold is disposed outwardly of the shaping ring mold and having a shape complementary to the shape of the peripheral edge of the glass sheet for supporting the peripheral edge of the glass sheet. The cooling ring mold has recesses defined in the upper surface thereof, and is covered with a punched metal.

Abstract: Ducts are provided to direct cooling gas onto the outer and interior surfaces of a rotating article of glassware that is heated to a uniform temperature above the strain point of the particular glass composition from which the glassware is formed in order to temper the glassware by producing beneficial residual compressive stresses on the surfaces. The ducts have gas emitting nozzles that shape the cooling gas streams to conform to the shape of the glassware surfaces. The ducts and nozzles are so positioned that the cooling gas impinges upon the glassware surfaces tangentially and in a direction opposite to the direction of rotation of the surfaces to increase the effective velocity of the gas and to promote laminar flow of the cooling gas over the surfaces and thereby enhance cooling.

Abstract: A glass sheet heating system (10) is disclosed as including a cradled roll conveyor (48) incorporated with a furnace (12) having roll contacting seals (58) that directly engage conveyor rolls (60) to prevent heat loss from the furnace. Each roll contacting seal (58) preferably includes a pair of rigid refractory seal holders (64,66) and a pair of soft blanket seals (68,70) made of refractory fibers. Sets of cradle rolls (72) on each side of the furnace have high traction drive elements (78) and cooperate in pairs to rotatably support the conveyor rolls (60) in planarity with each othe to convey glass sheets. A drive mechanism (80) provides driving of the cradle rolls 72 with sufficient friction to overcome the friction generated between the roll contacting seals (58) and the conveyor rolls (60).

Abstract: An adjustable quench for tempering hot glass sheets of varying transverse configurations, having overlapping members that seal a flexible nozzle assembly as it changes configurations. Nozzles extend from the flexible nozzle assembly towards the shaped glass sheet to be cooled such that the quenching surface formed by the head portions of the nozzles generally parallel the major surfaces of the shaped glass sheet. Each individual flexible nozzle assembly is connected to a common drive that can simultaneously flex all the nozzle assemblies.

Abstract: A glass sheet tempering method and system (10) disclosed utilizes a heating chamber (22) and a quenching chamber (26) which contain ambients at superatmospheric pressure during both the heating and quenching. Forced convection heating is preferably performed in an improved furnace (14"). In one embodiment, heated gas flow is provided by centrifugal blowers which blow air across a plurality of spaced heat tubes. The heated gas flow is directed toward a glass sheet positioned within the heating chamber to provide rapid heating of the glass sheet. In a second embodiment, the heated gas flow is provided by upper and lower sets of opposed gas jet pumps connected to a gas supply. A pressure gas supply including a compressor maintains the superatmospheric pressure of the heating and quenching chambers (22,26). A recirculating gas supply (32) feeds compressed quenching gas to opposed blastheads (28,30) to perform the tempering.

Abstract: In toughening a glass sheet, e.g. for use as an automobile window, by heating it to a temperature above the strain point and quenching the heated glass sheet by blowing a cooling medium such as compressed air against both sides of the glass sheet from two opposite sets of nozzles, the cooling medium is caused to impinge on each side of the glass sheet in such a pattern that the glass sheet is more efficiently quenched and consequently more highly toughened in a generally circular central region and a plurality of generally annular regions, which are substantially concentrical about the center of the glass sheet and radially spaced from one another, than in the remaining regions. This is effective in preventing the presence of impermissibly elongated particles when the glass sheet is fractured and also in lessening the difference between the maximum and minimum numbers of particles in unit areas of the fractured glass sheet.

Abstract: The invention relates to a frame for supporting a glass sheet in horizontal position during tempering. The frame is formed by a body and includes bearing members with bearing surfaces which support the glass sheet and which between them delimit channels for evacuation of blowing gases. The bearing members are located in at least a selected region of the body.

Abstract: A frame for holding a glass sheet in a substantially vertical position. The frame has two uprights joined by upper and lower crosspieces. A lower support means adapted to engage a bottom edge of a glass sheet is carried by the lower crosspiece. Upper support means freely movable in a vertical direction are adopted to engage the upper edge of the glass sheet and form part of the frame.

Abstract: The invention is concerned with the thermal tempering of glass sheets. In the practice of the invention, the glass blowing assemblies (3, 4) of a glass blowing device for the thermal tempering of glass sheets are formed of a plurality of tubular bodies (15) which are disposed side by side and provided with blowing outlets (20) which are directed towards the glass sheet. The tubular bodies (15) are interconnected by joints (34) and maintained in position by deformable guide rails (24). The shape of rails (24) is obtained by means of adjustable fixing means (40) whose position can be changed by programmable servo-motors (47). The adjustment of fixing means (40) causes with it that of guide rails (24) and accordingly the shape of the glass blowing assembly (3, 4) constituted by the tubular bodies (15) is adjusted to the shape of the glass sheet.The invention finds utility in the thermal tempering of glass sheets which are curved cylindrically and spherically.

Abstract: A glass furnace, e.g. for annealing or tempering glass, has a roller conveyor whose fused rollers rest upon stub rollers overshot by a belt which alternately overshoots and undershoots the stub rollers. A drive for the belt includes a pair of motors connected to the belt with overrunning clutches and driven in opposite senses to alternately drive the belt and thereby prevent play in the movement of the latter. The heater overlying the conveyor has a matrix array of individually or collectively controllable infra-red heaters.

Abstract: The invention relates to thermal quenching or tempering of glass by means of a gaseous jet directed by nozzles.According to the inventive method, the nozzles are supplied with gas and liquid under a pressure which enables the jet velocity attained at the exit of the nozzles to be at least sonic, said jet being comprised of a mixture of a gas and a finely divided liquid.In particular the gas may be air and the liquid water.The invention may be applied to vertical or horizontal quenching or tempering of sheets or other items of glass.

Abstract: A conveyor drive mechanism has a continuous drive loop trained over first, second, and third pulleys, with the first and second pulleys disposed in driving relationship to a support bed or conveyor, and a driving facility which supplies drive torque in either direction to the third pulley, to move the drive loop and conveyor in the selected direction. Counterpoised anti-backlash motors impart equal, opposed counter-torques to the first and second pulleys to impose a predetermined level of continuous tension in the active area of the drive loop, even during reversal of the direction of the torque transmitted by the driving facility.

Abstract: Apparatus is disclosed for tempering curved glass sheets suspended in a vertical orientation. The apparatus comprises a pair of opposed manifolds each having a plurality of nozzles and positional adjustment means to optimize the heat exchange effect between the tempering station and the sheet of glass. A first adjustment means adjusts the orientation of the manifold with respect to the surface of the glass by means of four independently adjustable screw jacks that mount the manifold on a frame. A second adjustment means adjusts the horizontal spacing between the manifold and the surface of the glass by means of four screw jacks that operate in unison. In addition, another displacement means permits the manifold to be displaced from its tempering position to facilitate the insertion and removal of the glass sheets between the two manifolds. Advantageously, the displacement means is mounted on the second adjustment means.

Abstract: A method is provided for the manufacture of glass containers (10) of the type having a sidewall (12) and having a bottom (16) that is thicker than the sidewall (12). The method comprises a step in which a centered portion (44) of the bottom (16) is cooled subsequent to the molding step. Cooling the centered portion (44) is effective to develop a reverse strain in the transition portion (42a) of the sidewall (12) that is proximal to the bottom (16). This reverse strain corrects the strain that is induced by unequal cooling of a relatively thin sidewall (12) and a relatively thick bottom (16) and results in a reduction of annealing time.

Abstract: A newly-moulded article of glassware is positioned on a dead plate with a central opening of the dead plate beneath a central region of the bottom of the article and a plurality of grooves or openings extending from beyond the article to beneath the bottom thereof. Air is sucked through the central opening so that it flows through the grooves or openings past the bottom of the article. Air is also blown on the sidewalls of the article through a plurality of nozzles uniformly spaced around the article.

Abstract: A tunnel furnace composed of modular sections, each modular section comprising horizontal and mutually parallel openings occupying the width of a heat treatment enclosure, the openings being beneath the top of a conveyor and adjacent each other in a direction parallel to the direction of travel of the conveyor with each opening extending perpendicular to the direction of travel, such that each opening gives out a sheet of ascending gas, a collecting slot formed in an upper wall of the heat treatment enclosure extending horizontally, mutually parallel, perpendicular to the direction of travel of the conveyor and extending the width of the enclosure, such that the slot collects the sheet of ascending gas, temperature adjusting devices for maintaining the temperature of the collected gas for the module, a circulating fan for accepting the collected gas and circulating the gas via a gas circulation path to the openings after passing through the temperature adjusting devices and a regulating device for controlling

Abstract: A glass furnace, e.g. for annealing or tempering glass, has a roller conveyor whose fused rollers rest upon stub rollers overshot by a belt which alternately overshoots and undershoots the stub rollers. A drive for the belt advantageously is controlled by a computer allowing display of the heater parameters etc. and includes a pair of motors connected to the belt with overrunning clutches and driven in opposite senses to alternately drive the belt and thereby prevent play in the movement of the latter. The heater overlying the conveyor has a matrix array of individually or collectively controllable infra-red heaters.

Abstract: A method and apparatus are disclosed for operating an air supply system for a glass sheet quench including a D.C. drive system of a variable speed blower operated on a duty cycle. A quench cycle and a cooling cycle are carried out in the quench. In the preferred embodiment shown for thin glass (i.e. glass which is 5 mm or less in thickness) the drive system is sized to the RMS requirements of the complete cycle to minimize the initial and operating costs, size and power requirements of the D.C. drive system.

Abstract: A method of quench-tempering a hot shaped glass sheet comprises supporting the sheet in a quenching station underneath a downwardly directed upper nozzle array and above an upwardly directed lower nozzle array by engagement of only a portion of the lower surface of the sheet. The portion engaged for support is interrupted by a generally uniformly distributed array of unsupported regions. An air stream is directed from the lower nozzle array up toward the lower surface of the glass sheet while an opposite air stream is directed down from the upper nozzle array toward the upper surface of the sheet. Generally all of the lower surface of the sheet is shielded except at the unsupported regions from the air stream of the lower nozzle array. A prestress field is thus formed in the sheet which corresponds to the distribution of the unsupported regions. The sheet is supported on and shielded by a plate having the same shape as the sheet but formed with holes at the unsupported regions.

Abstract: An improved glass sheet quench (14) is disclosed as including opposed blastheads (26,28) each of which includes elongated plenum housings (34) including openings (42) positioned therealong in a spaced relationship and oriented to supply jets (44) of quenching gas angularly in opposite directions from the plenum housing toward a heated glass sheet therebetween for impingement therewith to cool the glass sheet. This angular supply of the quenching jets permits the use of half as many plenum housings as is ordinarily needed such that the plenum housings can be spaced farther from each other to provide a greater flow area for spent quenching gas to escape from between the blastheads. Flat glass embodiments of the quench (14,14a) and bent glass embodiments of the quench (14' 14a) are disclosed and may incorporate sheet metal and tube plenum housings (34) or drilled metal bar plenum housings (34').

Abstract: Hot glass is thermally toughened by generating a stream of closely-packed, aerated particles, and projecting that stream towards the glass. A plurality of such streams are projected from an array of nozzles, and the velocity of projection of each stream is sufficient to ensure that the integrity of the stream is preserved in its trajectory towards the glass.

Abstract: The arrangement comprises a perforated dead plate above which a newly-moulded glassware article can be supported for cooling. Cooling means sucks air downwards through the dead plate so that the air flows past the article cooling it. The cooling means may comprise an air mover whose input end abuts the underside of the dead plate. A shroud may be provided which surrounds the article to force the air to flow downwards past the article.

Abstract: The invention provides apparatus and a method for thermally toughening glass by quenching the glass with a particulate material. A body of mobile aerated particulate material is created and gas extraction means and gas supply means are located in a region of the body through which a flow of the particulate material towards the glass is to be engendered. Regulation of the gas supply and extraction means regulates the mobility of the particulate material and permits the flow to be switched on and off.

Abstract: A method and apparatus for thermally toughening glass in which a hot glass article is quenched in a gas-fluidized bed of particulate material. A plurality of streams of particles are generated and are projected into the fluidized bed towards the glass immersed in the bed in order to enhance the heat transfer away from the surfaces of the article in the toughening process.

Abstract: A lehr for heat treating glass articles is assembled from a series of modules to define an elongated insulated tunnel. A belt conveyor extends throughout the tunnel for moving articles from one end to the other. Duct work connection between the tunnel and the ambient air and associated heating and blower means establish heating, tempering and cooling zones respectively within the lehr in the direction of conveyor movement. Temperature sensors adjacent both flights of the conveyor are linked with a control panel to permit establishment of any desired temperature curves.

Abstract: A composite blasthead (18,20,70,72,118,120) for a quench station (16) of a glass sheet tempering system (10) is disclosed as including outer layers (28,71,73,128,128') and an inner layer comprising inserts (30,32,34,74,76,130,130') therebetween for defining passages (36,80,82,136) through which cooling gas is supplied to a glass sheet in order to provide tempering. All of the inserts have inner end portions (38,40,42,81,138,138') that cooperate to define inlets (44,86,144,144') to the passages and also have outer end portions (46,48,50,88,146,146') that cooperate to define passage outlets (52,90,152,152') through which the quenching gas exits. All of the passages have a circular cross section along substantially the entire length of the passages.

Abstract: A roll (4) for conveying sheets of glass at a heat-tempering temperature horizontally through a heat-tempering furnace enclosure includes a core (10) of refractory metal and a shell (20). The shell (20) is formed of a refractory material composed of a calcium silicate base agglomerate having a specific mass of from 200 to 800 kg/m.sup.3.

Abstract: In tempering a glass sheet to a high temper by heating the sheet to approximately its softening point followed by rapid chilling using a quenching composition that comprises a tempering medium having high heat transfer characterisitcs, the heat-softened glass sheets are protected from breakage during fabrication and resulting optical distortion by applying the tempering medium through exit orifices of a delivery system toward the heated glass in a novel cycle. The initially applied tempering medium has a low heat transfer rate and is mixed with a second tempering medium having a higher heat transfer rate to gradually increase the heat transfer rate of the mixed tempering medium. In a specific embodiment, dry air is the first tempering medium and a sublimable material, such as carbon dioxide, is the second tempering medium. The delivery system has an uninsulated portion that assures that initially the sublimable material is applied as a gas.

Abstract: Apparatus for curving and tempering glass sheets, including a furnace for heating the glass sheets to softening temperature, shaping means for curving the heated glass sheets, and means for tempering the curved sheets arranged in tandum. The glass sheet shaping means includes upper and lower complemental pressing units, and a series of relatively narrow endless belts for receiving the glass sheets from the furnace, positioning them between the pressing units for curving and for subsequently delivering the curved sheets to the tempering means. The shaping means also includes means automatically operable to relieve the tension on the endless belts to bring the travel of the glass sheets to a stop between the pressing units during pressing and to reestablish the tension on said belts after pressing to deliver the curved sheets to the tempering means.

Abstract: Sheet glass is heated during conveyance within a furance housing having a fixed roof and vertically movable side doors that define side slots through which ends of conveyor rolls project outwardly to be supported and frictionally driven by continuous drive loops slidably driven over external support surfaces that extend alongside the side slots. A vacuum holder of the apparatus 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. A greater vacuum is drawn to initially support the glass and a lesser vacuum is subsequently drawn to prevent glass deformation at the spaced openings.

Abstract: An apparatus for arresting and locating a glass shaping mold in a fixed position on a continuous conveyor in vertical registry with a vertically reciprocal head for loading and unloading glass sheets onto and from the mold. The locating apparatus comprises laterally spaced locking heads rotatable between a mold receiving position and a mold locking position. The heads are mounted for vertical movement between the operative position above the conveyor and an inoperative, out-of-the-way position below the conveyor.

Abstract: Hot glass panes are displaced without sagging through a treatment station, such as an oven, on a roller grate which is linearly reciprocated while the rollers of the grate receive a translatory angular velocity component and an angular oscillation so that the velocity at a glass pane relative to the traveling grate is R.multidot..omega..sub.osc +R.multidot..omega..sub.trans, where R is the radius of the rollers at a point of contact with the pane, .omega..sub.osc is the angular oscillation velocity component of the roller displacement and .omega..sub.trans is the angular translatory component.

Abstract: Nozzles are arranged in different densities transverse to a path of travel for glass sheets moving through a pass-through quench to facilitate removal of spent tempering medium to both lateral sides of said path of travel.

Abstract: Heat strengthened glass is treated to have a break pattern that permits the fractured glass sheet to be retained within an installation frame by moving a glass sheet through a heating area, force cooling the side portions of the moving sheet while cooling the intermediate portions of the sheet at a lesser rate to establish a temperature gradient between the side portions and the intermediate portion, and subsequently applying quenching medium to the entire moving sheet. The temperature gradient in the sheet is achieved by a plurality of baffles, e.g. plates having an imperforate center portion and apertured or slotted end portions and facilities movable relative to quenching nozzles to control passage of quenching medium through the slotted end portions of the baffles to control the temperature gradient imparted to the glass sheet. The movable facilities also permit tempering of glass sheets of varying transverse dimensions.

Abstract: A method and quench unit (10,10a,10b) disclosed provide tempering of a heated glass sheet by impinging pressurized air against its opposite surfaces while within a chamber (18) at super-atmospheric pressure. An enclosure (16) of the quench unit defines the chamber (18) and is preferably pressurized by the spent quenching air which is delivered through opposed blastheads (12). The spent quenching air is removed from the chamber (18) to maintain the air pressure below a predetermined level. An air supply system (24) disclosed cools and pressurizes the spent quenching air received from the chamber (18) and then feeds this air back to the blastheads (12) in a recirculating fashion for impingement with the glass sheet in the chamber.

Abstract: The present invention is directed to an apparatus and process for the ion change hardening of glassware by passing the glassware through a stream of molten salt. The glassware may be arranged at different levels on a conveying means, provided with perforations to allow the molten salt to fall from level to level from an overhead salt distributor. The glassware may be positioned on a horizontally spinning rack so that molten salt continuously fills up and empties from the glassware. The molten salt is recycled from the bottom of the apparatus and may be replenished by adding salt to the recycle stream.

Abstract: A traveling grate for hot glass prevents sagging of the glass by displacing the grate at a velocity different from the angular velocity imparted to the grate rollers in the opposite direction so that the translatory velocity imparted to the glass is an algebraic summation of the grate velocity and .omega.R where .omega. is the angular velocity of the rollers and R is the radius thereof.

Abstract: A conveyor roll for conveying glass sheets and a conveyor comprising a plurality of said conveyor rolls is described. Each conveyor roll comprises a curved shaft conforming to the shape of said glass sheets transverse to their path of movement. A plurality of segments of essentially cylindrical configuration is mounted around said curved shaft. The segments have loosely interfitting tongues and grooves and a cylindrically shaped surface of a material that does not mar glass. When torque is applied to one of the end segments of said conveyor rolls, the glass engaging surfaces rotate in unison to convey the curved glass sheets through a treatment station included in glass sheet treating apparatus. A spring mounted about the shaft in position to apply axial pressure against the outer axial surface of the end segment to insure positive tongue in groove engagement would tend to mar said outer axial surface and to cause the end segment to drag in the absence of the present invention.

Abstract: In the bending and tempering of glass sheets supported on a ring-like member for conveyance of the bent glass sheet through a cooling station, a transfer device for unloading the bent, tempered glass sheet is provided. The transfer device is so constructed and arranged that it does not cause a bottleneck in high speed, mass production of bent, tempered glass sheets, avoids uncontrolled departures from the desired shape of the bent, tempered glass sheets, particularly those that develop in the marginal edge portion of the glass sheets that must fit exactly into glass sheet receiving frames of installation structures or vehicles, and enables the glass sheet to transfer so gently as to inhibit the likelihood of breakage resulting from uncontrolled dropping of bent, tempered glass sheets during their handling.

Abstract: Sheet glass is heated during conveyance within a furnace housing having a fixed roof and vertically movable side doors that define side slots through which ends of conveyor rolls project outwardly to be supported and frictionally driven by continuous drive loops slidably driven over external support surfaces that extend alongside the side slots. A vacuum holder of the apparatus 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. A greater vacuum is drawn to initially support the glass and a lesser vacuum is subsequently drawn to prevent glass deformation at the spaced openings.

Abstract: Sheet glass is heated during conveyance within a furnace housing having a fixed roof and vertically movable side doors that define side slots through which ends of conveyor rolls project outwardly to be supported and frictionally driven by continuous drive loops slidably driven over external support surfaces that extend alongside the side slots. A vacuum holder of the apparatus 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. A greater vacuum is drawn to initially support the glass and a lesser vacuum is subsequently drawn to prevent glass deformation at the spaced openings.