Pilkington Glass Limited

David Sykes

Alan Charles Woodward

James Boardman

Neil W Jacques

Brian J Thomas

An apparatus for press bending glass sheets carried on a mold, the apparatus including a die having a lower surface shape to mold a glass sheet positioned thereunder to a desired curved shape, a first counterbalance assembly connected to the die for providing the die with a selected net weight, a frame mounted above the die, a plurality of flexible members connecting the die to the frame for suspending the die below the frame whereby the die is capable of unconstrained lateral and tilting movement relative to the frame and die moving device connected to the frame for vertically moving the die. The present invention also provides a method of press bending glass sheets, the method includes the steps of providing a gravity bent glass sheet carried on a gravity bending mold; lowering an upper die by a suspension system onto the glass sheet, the upper die having a lower surface to mold the glass sheet to a desired curved shape, and releasing the upper die from being supported by the suspension system so that the upper die rests on the glass sheet at a selected net weight during a press bending operation; and wherein during the lowering step the upper die is unconstrained against lateral and tilting movement so that the upper die is permitted progressively to be aligned with the bent glass sheet as the upper die comes into contact with the bent glass sheet.

Apparatus for and method of bending glass sheets

An apparatus for bending a glass sheet in a gravity bending step and in a subsequent press bending step includes a gravity bending mould having a fixed mould portion and an articulated wing portion adjacent to the fixed mould portion, a base on which the fixed mould portion is mounted and a hinged locking arm mounted between the wing portion and the base. The locking arm is movable from an unlocked position in which the wing portion is capable of moving vertically relative to the base to a locked position in which the wing portion is fixed in position relative to the base. A method of bending a glass sheet involves placing a glass sheet on a gravity bending mould having an articulated wing portion and a fixed mould portion, and conveying the mould carrying the glass sheet through a furnace in which the glass is heated to the glass softening point and is bent by gravity until the periphery of the glass sheet is in contact with and conforms to the shape of the upper surface of the gravity bending mould. The wing portion is provided with a locking arm which, during gravity bending, progressively moves from an unlocked position to a locked position at which the wing portion is fixed in a predetermined position corresponding to the desired shape of the glass sheet. The glass sheet is then press bent, while the glass sheet is supported by the gravity bending mould.

An apparatus for press bending glass sheets, the apparatus comprising an upper die, a suspension system for the upper die for suspending and vertically moving the upper die, a lower gravity bending mould and a plurality of spacer devices for spacing the upper die and the lower mould a selected distance from each other when the upper die presses a glass sheet on the lower mould, the suspension system being adapted and the spacer devices being configured to permit lateral movement of the die relative to the mould. There is also provided a method of press bending glass sheets.

Apparatus for and method for bending glass sheets

A method is provided in which a glass sheet is bent on a mould having a movable end, comprising the steps of: heating the glass sheet to its bending temperature; subjecting the glass sheet to an initial gravity bending step; providing support to a portion of the glass sheet located on the movable end of the mould; while providing said support, lowering said movable end away from the glass sheet; subjecting the glass sheet to a press bending step; cooling the bent glass sheet. Support may be provided by a reduced pressure within an upper mould, a mechanical arm, or gas directed in a generally upwards direction. The invention may be used for bending glass for architectural or automotive purposes, e.g. for bending a pair of glass sheets, one on top of the other, for use in the manufacture of a laminated windscreen, to achieve deep and/or complex bent shapes.

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Wigan, United Kingdom

David Sykes