Other

Glasstech, Inc.

Glasstech International L.p.

Norman C Nitschke

Harold A McMaster

John S Nitschke

Ronald A McMaster

Dexter H McMaster

Thomas E Feehan

A method for bending glass sheets is disclosed in which a heated glass sheet (12) is introduced between spaced upper and lower bending platens (16,18). Heat source (19), integral with platen (18), is operable for applying heat in close proximity to the glass sheet (12) between the platens (16,18) to maintain an optimal bending temperature and the glass sheet (12) is bent such that a specific geometric orientation of the bend on the glass sheet (12) is controllable and repeatedly reproducible during a production operation.

Method for bending glass sheets

A glass bending and tempering apparatus (10) is disclosed as including a first platen (14) for receiving a heated glass sheet (12) to be bent. The first platen (14) is deformable and includes an actuator (16) for deforming platen (14) from a planar shape to a bent shape. A second platen (22) is mounted above lower platen (14) for bending and quenching glass sheet (12) therebetween the platens. A template (24) is located on the other side of the second platen (22) away from glass sheet (12). Second platen (22) is pressed against template (24) as first platen (14) is deformed from the planar shape to the bent shape to bend the heated glass sheet thereagainst second platen (22), the second platen (22) conforming to template (24). Quenching gas is supplied by both platens (14,22) through quench openings (18) that move with the platens (14,22) to temper the bent glass sheet between the platens.

Glass sheet bending and tempering apparatus

A glass bending and tempering apparatus (20) is disclosed as including a pair of opposed bending platens (24) for receiving a heated glass sheet (22) to be bent therebetween. At least one of the bending platens (24) is deformable and includes an actuator (32) for deforming the platens from a planar shape to a bent shape to bend the heated glass sheet. Said one platen (24) includes quench openings (42) that move with said platen during the deformation of the platen and subsequently supply quenching gas to temper the bent glass sheet (22).

Glass bending and tempering apparatus

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. Vertically movable auxiliary lifters positioned between the rolls or vertical movement of the vacuum holder facilitates glass pickup. Sensing of the glass position along the conveyor and operation of a locator cooperatively provide accurate positioning of the glass on the holder surface without requiring the conveyor to be stopped prior to the holder operation. 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 between upper and lower blastheads that temper the bent glass. Increased air is then supplied to the lower blasthead relative to the upper blasthead to lift the glass sheet off the ring and allow return of the ring to the furnace.

Apparatus and method for bending glass sheets

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. Vertically movable auxiliary lifters positioned between the rolls or vertical movement of the vacuum holder facilitates glass pickup. Sensing of the glass position along the conveyor and operation of a locator cooperatively provide accurate positioning of the glass on the holder surface without requiring the conveyor to be stopped prior to the holder operation. 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 between upper and lower blastheads that temper the bent glass. Increased air is then supplied to the lower blasthead relative to the upper blasthead to lift the glass sheet off the ring and allow return of the ring to the furnace.

Apparatus for bending and tempering glass sheets

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. Vertically movable auxiliary lifters positioned between the rolls or vertical movement of the vacuum holder facilitates glass pickup. Sensing of the glass position along the conveyor and operation of a locator cooperatively provide accurate positioning of the glass on the holder surface without requiring the conveyor to be stopped prior to the holder operation. 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 between upper and lower blastheads that temper the bent glass. Increased air is then supplied to the low blasthead relative to the upper blasthead to lift the glass sheet off the ring and allow return of the ring to the furnace.

Apparatus and method for handling heated glass sheets

Apparatus and method for removing a glass sheet from a carrier

A roll drive mechanism (14) for a horizontal roller conveyor (12) of glass sheet processing equipment (10) has particular utility with a heating furnace (18) of a glass sheet tempering system. First and second continuous drive loops (22,24) of the drive mechanism extend along the conveyor and are alternately engageable in a driving relationship with conveyor rolls (16) over associated lengths (26,28,30) of the conveyor that are selectively adjustable to provide a desired transition between adjacent conveyor sections driven by different drive loops. First and second electric motor drives (32,34) respectively drive the loops to provide synchronous or independent glass sheet conveyance over the different lengths of the conveyor. A pair of each of the first and second drive loops (22,24) are preferably utilized with opposite ends of the conveyor rolls supported thereon and having driven and reduced size portions (88,90 and 86,92) that permit end-for-end roll repositioning to adjust the transition between the driving of the loops. The preferred construction utilizes chains as the drive loops (22,24) with the roll ends projecting outwardly through side slots (66) in the furnace (18) for frictional driving of the rolls by the chains.

Roll drive mechanism for glass sheet processing equipment

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.

Apparatus for bending and tempering glass

A method and apparatus for filming and tempering a pre-cut glass sheet in a continuous process. The glass sheet is heated initially to a temperature sufficient for pyrolysis. The heated glass is sprayed with a coating composition which reacts with the glass to form a metal oxide film on its surface. The filmed glass is re-heated to both restore the heat lost by spraying and to bring its temperature to a level sufficient for tempering. The glass sheet is then tempered by subjecting it to rapid cooling. The method can be modified to include a secondary spraying wherein after the glass is first sprayed it is re-heated as in the initial step and then re-sprayed before completing the process. Apparatus for carrying out the above described method is also disclosed.

Method and apparatus for forming tempered sheet glass with a pyrolytic

A spring end cap for use in rotatably driving a glass conveyor roll of ceramic is disclosed as incorporating helical spring coils that clamp onto an end of the roll. Each spring coil has a diameter in an undeflected condition slightly less than the diameter of the roll end so that coil deflection increasing the coil diameter allows the coils to receive the roll end prior to being released in order to clamp over a round outer surface of the end. Different embodiments of the end cap are utilized with frictionally driven rolls as well as with toothed sprocket or gear driven rolls. Ease of installation is achieved when the spring coils are all part of a single helical spring. The end cap can also be utilized to repair a broken roll end and then must include at least three helical springs whose coils are axially threaded so as to provide circumferentially spaced clamping that secures the broken roll end to the rest of the roll at the fracture.

Spring end cap for conveyor rolls

A furnace for treating glass sheet material and the like in a glass tempering system. The furnace includes an upper glass treating zone and a lower gas treating and distributing zone for homogenizing gases of different temperatures to minimize exposure of the sheet being treated in the treating zone to uneven temperatures. Diametrically opposed inlets and outlets are provided in the side walls controlled by doors, and a slot in the top wall extends between the inlets and outlets to permit movement of a material carrier through the furnace. A pressure chamber communicates with the slot to cool conveyor elements at the top of the furnace, and also to provide a pressure barrier resisting the escape of gases from the furnace through the slots. Air curtains impinge on the tops of the doors in their closed positions to reduce leakage at the top of the doors.

Glass treating furnace

A roller hearth furnace having a plurality of horizontally elongated furnace modules aligned with each other in an end-to-end relationship so a roller conveyor may carry glass sheets horizontally through the furnace and thereby heat the glass prior to tempering. Each furnace module has a hollow construction with a circular cross-section defined by a semicircular lower housing portion and a semicircular upper housing portion. A separate counterbalance mechanism associated with each upper housing portion supports it independently of the others for movement between a lower closed position immediately over its associated lower housing portion and an upper open position where the interior of its associated lower housing portion is accessible. The counterbalance mechanisms each include four chains attached to counterweights in a manner that permits counter-balancing of the associated upper housing portion even if one chain should break. One chain of each counterbalance mechanism is driven by an associated reversible electric motor to raise and lower its upper housing portion, and a separate elongated operator handle extending along the length of each upper housing portion is coupled to the motor thereof so an operator can control the motor operation from any position along the length of the particular furnace module. Each upper housing portion includes end walls that mitigate heat loss when one of them is open while adjacent ones are closed. Upper and lower end walls at each end of the furnace are reinforced to maintain horizontal openings of uniform size where glass enters and leaves the furnace.

Roller hearth furnace for glass sheets

A glass tempering system including a roller hearth furnace that has a conveyor with elongated rollers extending through an elongated heating chamber of the furnace and outwardly through elongated slots in the sides of the furnace so as to be supported on drive belts which are slidably driven along support surfaces to thereby frictionally drive the rollers and convey glass sheets over the rollers through the heating chamber. The furnace is of a modular construction and includes upper and lower housing portions with inner layers of refractory material that define the heating chamber. Flanges of the refractory material cooperate to define the elongated slots at the sides of the furnace. Heat seal arrangements extend between the refractory flanges and the conveyor rollers to mitigate heat flow from the furnace during use. A first electric motor drive mechanism drives belt sheaves that receive the drive belt at the end of the furnace where glass enters the heating chamber. Vertical support members carry belt sheaves receiving the drive belts at the other end of the furnace and are hydraulically positioned to control the tension of the belts. A secondary conveyor of the system receives the heated glass sheets after leaving the furnace and carries them through quench and cooling units of the system. The secondary conveyor is driven by a second electric motor drive mechanism which is coupled to the first conveyor to tension portions of the furnace conveyor drive belts in a manner that increases the driving force the first drive mechanism can impart to its drive belts. The secondary conveyor includes a pair of continuous drive chains that frictionally drive rollers of this conveyor in a manner similar to the driving of the furnace conveyor rollers. The tension of the secondary conveyor chains is hydraulically controlled.

Glass tempering system

A furnace for heat treating glass sheet material including a circular enclosure having top, bottom and side walls of refractory material. Inlet and outlet openings are formed in the side walls. The side walls have an outer insulating layer and an inner layer of material having a low coefficient of thermal expansion, the inner layer having spaced end portions projecting beyond the outer layers and the periphery of the side walls to define said inlet and outlet openings. Each opening is controlled by doors, and each door includes an elongated support bar with a plurality of blocks of refractory material supported on the bar in end-to-end relationship. The blocks are adjustably secured to the bar to accommodate irregularities in the openings.

Growing community of inventors

Perrysburg, OH, United States of America

Norman C Nitschke