Patent US3632326A successfully refreshed from Google Patents.
US3632326A
Expired / Lapsed
US
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Method and apparatus for bending glass sheets
Assignee: Pilkington North America Inc
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Filing: 1969-09-25
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Granted: 1972-01-04
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Expires: 1989-09-25
Abstract
Abstract A method and apparatus for bending glass sheets in which a sheet is heated, prebent convexly upward by applying a jet of cool air to the upper surface thereof, and then bent in the opposite direction on an inertia-gravity bending mold. The apparatus includes an air nozzle which is arranged and controlled such that cooling air is applied only to the central area of the sheet in order to prevent edge vents from occurring.
Inventors
- 👤 George F Ritter Jr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 18:01
CPC Classifications
C; C03; C03B; C03B23/00; C03B23/02; C03B23/023; C03B23/025; C03B23/0256
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
72 words
In a method for bending horizontally disposed heat-softened glass sheets by accelerating a sheet upwardly to cause it to sag into conformity with a concave shaping surface, the improvement comprising the step of prebending the sheet in the opposite direction from the desired bend, before it is subjected to said acceleration, by differentially cooling the upper and lower surfaces of the sheet with the greater cooling being applied to the upper surface.
Claim 2
Dependent Claim
72 words
In a method for bending horizontally disposed heat-softened glass sheets by accelerating a sheet upwardly to cause it to sag into conformity with a concave shaping surface, the improvement comprising the step of prebending the sheet in the opposite direction from the desired bend, before it is subjected to said acceleration, by differentially cooling the upper and lower surfaces of the sheet with the greater cooling being applied to the upper surface.
Claim 3
Dependent Claim
28 words
A method for bending glass sheets as claimed in claim 1, in which at least one surface of said sheet is cooled by sweeping with pressurized cooling gas.
Claim 4
Dependent Claim
22 words
A method for bending glass sheets as claimed in claim 2, in which the upper surface only is swept by cooling gas.
Claim 5
Dependent Claim
35 words
A method for bending glass sheets as claimed in claim 2, in which said pressurized gas is applied to the central area only of the sheet surfaces, leaving the marginal edge portions substantially untouched thereby.
Claim 6
Independent Claim
83 words
A method for bending horizontally disposed glass sheets, comprising the steps of heating a sheet to the softening point, prebending the sheet by applying cooling air to the central area of the upward facing surface thereof, supporting said sheet over a bending mold having a contoured, upward-facing shaping surface formed thereon, and then accelerating said mold member rapidly upward to lift said sheet bodily to cause it to sag in conformity with said shaping surface under the influence of inertial and gravitational forces.
Claim 7
Independent Claim
83 words
A method for bending horizontally disposed glass sheets, comprising the steps of heating a sheet to the softening point, prebending the sheet by applying cooling air to the central area of the upward facing surface thereof, supporting said sheet over a bending mold having a contoured, upward-facing shaping surface formed thereon, and then accelerating said mold member rapidly upward to lift said sheet bodily to cause it to sag in conformity with said shaping surface under the influence of inertial and gravitational forces.
Claim 8
Independent Claim
144 words
A method of bending each of a plurality of glass sheets, comprising supporting each sheet in a substantially horizontal plane, moving the sheet thus supported along a predetermined path, heating the sheet as it travels along said path to substantially the softening point of the glass, initially cooling the upper surface only of said sheet as it moves along said path at a rate sufficient to cause the center of said sheet to bow upward to a predetermined curvature, stopping said sheet above a bending mold member having an upward facing concave shaping surface formed thereon, moving said mold member upward through said path into contact with the sheet, and then accelerating said mold member and said sheet bodily upward, said acceleration being sufficient to cause the sheet to settle into registry with said shaping surface under the influence of inertial and gravitational forces.
Claim 9
Independent Claim
144 words
A method of bending each of a plurality of glass sheets, comprising supporting each sheet in a substantially horizontal plane, moving the sheet thus supported along a predetermined path, heating the sheet as it travels along said path to substantially the softening point of the glass, initially cooling the upper surface only of said sheet as it moves along said path at a rate sufficient to cause the center of said sheet to bow upward to a predetermined curvature, stopping said sheet above a bending mold member having an upward facing concave shaping surface formed thereon, moving said mold member upward through said path into contact with the sheet, and then accelerating said mold member and said sheet bodily upward, said acceleration being sufficient to cause the sheet to settle into registry with said shaping surface under the influence of inertial and gravitational forces.
Claim 10
Dependent Claim
141 words
In apparatus for bending each of a plurality of horizontally disposed glass sheets, including means for moving said sheets along a horizontal path; a furnace disposed along said path for heating said sheets to the softening point; and bending means disposed along said path beyond said furnace, said bending means comprising a ring-type mold member having an upward-facing, concave shaping surface formed thereon disposed below said path, and means for accelerating said mold member upwardly to lift said sheet bodily upward from said path thereby creating combined inertial and gravitational forces bending said sheet into registry with said shaping surface; the improvement which comprises locating prebending means, comprising means for cooling a portion of the upper surface of a sHeet to cause the sheet to bow upwardly at the center, above said sheet and between said furnace and said bending means.
Claim 11
Dependent Claim
141 words
In apparatus for bending each of a plurality of horizontally disposed glass sheets, including means for moving said sheets along a horizontal path; a furnace disposed along said path for heating said sheets to the softening point; and bending means disposed along said path beyond said furnace, said bending means comprising a ring-type mold member having an upward-facing, concave shaping surface formed thereon disposed below said path, and means for accelerating said mold member upwardly to lift said sheet bodily upward from said path thereby creating combined inertial and gravitational forces bending said sheet into registry with said shaping surface; the improvement which comprises locating prebending means, comprising means for cooling a portion of the upper surface of a sHeet to cause the sheet to bow upwardly at the center, above said sheet and between said furnace and said bending means.
Claim 12
Dependent Claim
34 words
Apparatus for bending glass sheets as claimed in claim 7, including means for restricting the effective area of said cooling means to an area spaced inwardly of the marginal edge portions of said sheet.
References Cited (Backward Citations)
US3468645A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-01-03 | 1975-07-05 | 1976-01-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-03 | 1979-07-05 | 1980-01-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-03 | 1983-07-05 | 1984-01-04 | $7700.00 | Window Closed / Lapsed |