| 摘要 |
When glass sheets are shaped by drop forming a glass sheet released from vacuum engagement against the bottom perforated plate of a vacuum platen to drop onto a shaping mold of ring-like construction, the intermediate portion of the glass sheet can develop excessive downward sag. The present invention discloses different techniques to develop an upward bow in the intermediate portion of the glass sheet sufficient to compensate approximately for the undesired excessive downward sag.
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