Abstract: For bending a glass sheet so that the glass sheet has a compound curvature, an apparatus comprises a furnace including hearth beds on a bed support and a quenching unit provided with upper and lower air blowers. The final hearth bed may have a top surface with a simple curvature, be provided with one upstream corner cut away thereby defining a cut surface section and arranged in such a manner that the cut surface section is nearly parallel to the hearth bed adjacent to the final hearth bed. Alternatively, the final hearth bed may have a top surface with a compound curvature, so that the glass sheet is bent under the conditions set by controlling a temperature in a downstream part of the furnace, adjusting the inclination of the lower air blower and/or rotating final hearth bed so as to reverse the upstream and downstream ends thereof.

Abstract: An apparatus for bending a glass sheet includes a final hearth bed. This final hearth bed has a top surface that is upwardly convexly curved along a plane perpendicular to an axis of the glass sheet. The top surface has an upstream end, a downstream end that is at a level lower than that of the upstream end, and an intermediate point defined therebetween. The top surface has (a) a first section that extends from the upstream end to the intermediate point and that is parallel with the axis or upwardly inclined relative to the axis and (b) a second section that extends from the intermediate point to the downstream end and that is downwardly inclined relative to the axis. The final hearth bed has a bottom surface that is along the first direction or inclined downwardly relative to the first direction.

Abstract: For bending a glass sheet so that the glass sheet has a compound curvature, an apparatus comprises a furnace including hearth beds on a bed support and a quenching unit provided with upper and lower air blowers. The final hearth bed may have a top surface with a simple curvature, be provided with one upstream corner cut away thereby defining a cut surface section and arranged in such a manner that the cut surface section is nearly parallel to the hearth bed adjacent to the final hearth bed. Alternatively, the final hearth bed may have a top surface with a compound curvature, so that the glass sheet is bent under the conditions set by controlling a temperature in a downstream part of the furnace, adjusting the inclination of the lower air blower and/or rotating final hearth bed so as to reverse the upstream and downstream ends thereof.

Abstract: For bending a glass sheet so that the glass sheet has a compound curvature, an apparatus comprises a furnace including hearth beds on a bed support and a quenching unit provided with upper and lower air blowers. The final hearth bed may have a top surface with a simple curvature, be provided with one upstream corner cut away thereby defining a cut surface section and arranged in such a manner that the cut surface section is nearly parallel to the hearth bed adjacent to the final hearth bed. Alternatively, the final hearth bed may have a top surface with a compound curvature, so that the glass sheet is bent under the conditions set by controlling a temperature in a downstream part of the furnace, adjusting the inclination of the lower air blower and/or rotating final hearth bed so as to reverse the upstream and downstream ends thereof.

Abstract: An apparatus for bending a glass sheet includes a final hearth bed. This final hearth bed has a top surface that is upwardly convexly curved along a plane perpendicular to an axis of the glass sheet. The top surface has an upstream end, a downstream end that is at a level lower than that of the upstream end, and an intermediate point defined therebetween. The top surface has (a) a first section that extends from the upstream end to the intermediate point and that is parallel with the axis or upwardly inclined relative to the axis and (b) a second section that extends from the intermediate point to the downstream end and that is downwardly inclined relative to the axis. The final hearth bed has a bottom surface that is along the first direction or inclined downwardly relative to the first direction.

Abstract: For bending a glass sheet so that the glass sheet has a compound curvature, an apparatus comprises a furnace including hearth beds on a bed support and a quenching unit provided with upper and lower air blowers. The final hearth bed may have a top surface with a simple curvature, be provided with one upstream corner cut away thereby defining a cut surface section and arranged in such a manner that the cut surface section is nearly parallel to the hearth bed adjacent to the final hearth bed. Alternatively, the final hearth bed may have a top surface with a compound curvature, so that the glass sheet is bent under the conditions set by controlling a temperature in a downstream part of the furnace, adjusting the inclination of the lower air blower and/or rotating final hearth bed so as to reverse the upstream and downstream ends thereof.

Abstract: A film conveying apparatus includes a conveying mechanism and a speed control mechanism. The conveying mechanism includes a plurality of lower rollers arranged in a lateral direction perpendicular to a film conveyed direction. The lower roller is equipped with a motor to variably control its speed. A plurality of upper rollers is disposed to correspond to the lower rollers so as to sandwich the continuous film with the lower rollers. The roller-speed control mechanism controls a rotation speed of each lower roller so that the film is conveyed at a desired speed in a desired direction.

Abstract: The invention relates to the application of a releasing agent to a surface of a glass plate which is to be subsequently bent in a heated state together with another glass plate thereon. The glass plate is held in a standing posture, and hot air is blown perpendicularly against a surface of the glass plate, and simultaneously an aqueous solution of a releasing agent is sprayed from a plurality of spray nozzles into a space in front of the glass plate surface such that the sprayed solution mixes with the hot air before arriving at the glass plate surface. In an embodiment the spray nozzles are directed parallel to the glass plate or obliquely so as to make a small acute angle with the glass plate and arranged such that the hot air forces droplets of the sprayed solution to move toward the glass plate surface together with the hot air. In another embodiment the spray nozzles are directed perpendicularly toward the glass plate and arranged such that the sprayed solution soon mixes with the hot air.

Abstract: A mold for forming a curved window glass with deeply bent end portions includes a stationary main frame for forming a gently curved main portion of the window glass and a pair of swingable side frames for forming the deeply bent end portions. A weight plate is installed on each side frame so as to be movable toward and away from same. A plurality of pushing members are installed on the weight plate and alignable with corresponding ones of supporting members for supporting the glass plate on the side frame. The pushing members are constructed and arranged so as to contact with only an edge of a lateral end of the glass plate.

Abstract: A glass plates positioning device for positioning overlapped larger and smaller glass plates on a belt conveyer is disclosed, which includes a light device and pushing portions. The lift device lifts up the glass plates from the belt conveyer and lowers the same onto the belt conveyer. In a lifted position, the glass plates are horizontally universally movably supported by the lift device and positioned by the pushing portions. Each pushing portion is shaped like a spinning top, which includes concentrically connected smaller and larger disc portions. Each pushing portion horizontally abuts against and pushes each side edge of the glass plates to a predetermined position, wherein side surface of the larger disc is in contact with the edge of the smaller glass plate and the side surface of the smaller disc is in contact with the edge of the larger glass plate. After the positioning of the glass plates, the glass plates are lowered onto the belt conveyer by the lift device.

Abstract: The invention relates to heat treatment of a glass plate for strengthening only a peripheral region of the glass plate while annealing the major region. The glass plate is heated to a temperature of 550.degree.-650.degree. C. and placed on a ring-like holder which is maintained at a temperature lower than the temperature of the glass plate by 100.degree. to 600.degree. C. such that the peripheral region of the glass plate makes contact with a ring-like upper surface of the holder. Then glass palte on the ring-like holder is kept in an annealing chamber maintained at a temperature in the range from 50.degree. to 500.degree. C. and not higher than the initial temperature of the ring-like holder. After that the glass plate is allowed to cool down to room temperature. This method is applicable to either flat glass plates or curved glass plates and very suitable for treating glass plates ranging from 1.5 to 3.0 mm in thickness.

Abstract: This invention relates to a mold carriage for carrying thereon a mold for bending a glass sheet, or a stack of glass sheets to be laminated, placed thereon into a curved shape by heating in a furnace. To locally intensely heat the glass sheet in a selected area to be bent sharply relative to the major area, the mold carriage is installed with a heater to heat a selected area of the glass sheet from underneath, a holder to hold the heater and adjust the position of the heater, and a heater support to support thereon an external heater which is suspended from a separate member disposed in the furnace to heat the afore-mentioned area of the glass sheet from above. The heater support also can adjust the position of the external heater.