Method for bending a glass sheet and apparatus therefor

{
  "publication_number": "US2005138967A1",
  "country": "US",
  "kind": "A1",
  "title": "Method for bending a glass sheet and apparatus therefor",
  "abstract": "There are a preliminarily bending step for putting heated and softened glass sheet on a preliminarily bending supporting-frame, the glass sheet having an edge portion supported by the preliminarily bending supporting-frame, and for bending the glass sheet into a desired preliminarily bent shape while putting the glass sheet on the preliminarily bending supporting-frame; and a finally bending step for transferring the preliminarily bent glass sheet on a finally bending supporting-frame, the glass sheet having an edge portion supported by the finally bending supporting-frame, and for bending the glass sheet into a final bent shape by pressing the glass sheet against a bending surface of a finally bending mold while putting the glass sheet on the finally bending supporting-frame.",
  "claims": [
    "1. A method for bending a glass sheet, which comprises a heating step for heating and softening a glass sheet, and a bending step for bending the heated and softened glass sheet in a desired shape; wherein the bending step comprises: a preliminarily bending step for putting the heated and softened glass sheet on a preliminarily bending supporting-frame, the glass sheet having an edge portion supported by the preliminarily bending supporting-frame, and for bending the glass sheet into a desired preliminarily bent shape while putting the glass sheet on the preliminarily bending supporting-frame; and a finally bending step for transferring the preliminarily bent glass sheet on a finally bending supporting-frame, the glass sheet having an edge portion supported by the finally bending supporting-frame, and for bending the glass sheet into a final bent shape by pressing the glass sheet against a bending surface of a finally bending mold while putting the glass sheet on the finally bending supporting-frame.",
    "2. The method according to claim 1, wherein an amount of deformation of the glass sheet in the preliminarily bending step is from 20 to 80% of an amount of deformation of the glass sheet caused in a course of from the heating step to the finally bending step.",
    "3. The method according to claim 1, wherein the preliminarily bending step and the finally bending step are performed in a heating furnace.",
    "4. The method according to claim 1, wherein the preliminarily bending step comprises at least one step or a combination of at least two steps selected from the group consisting of a) a step for pressing the glass sheet between the preliminarily bending supporting-frame and a preliminarily bending mold, b) a step for sucking a lower surface of the glass sheet put on the preliminarily bending supporting-frame, c) a step for heating at least one portion of the glass sheet put on the preliminarily bending supporting-frame, and d) a step for employing a vertically movable ring element to support one portion of the glass sheet put on the preliminarily bending supporting-frame.",
    "5. An apparatus for bending a glass sheet, which comprises a heater for heating and softening a glass sheet, and a bending device for bending the heated and softened glass sheet in a desired shape; wherein the bending device comprises: a preliminarily bending unit including a preliminarily bending supporting-frame and a preliminarily bending means, the glass sheet being put on the preliminarily bending supporting-frame and having an edge portion supported by the preliminarily bending supporting-frame, the preliminarily bending means bending the glass sheet in a desired preliminarily bent shape while the glass sheet is put on the preliminarily bending supporting-frame; and a finally bending unit including a finally bending supporting-frame and a finally bending mold, the preliminarily bent glass sheet being put on the finally bending supporting-frame and having an edge portion supported by the finally bending supporting-frame, the glass sheet being pressed by the finally bending mold, whereby the glass sheet is bent in a final bent shape.",
    "6. The apparatus according to claim 5, wherein an amount of deformation of the glass sheet caused by the preliminarily bending unit is from 20 to 80% of an amount of deformation of the glass sheet finally caused.",
    "7. The apparatus according to claim 5, wherein the preliminarily bending unit comprises at least one element or a combination of at least two elements selected from the group consisting of a) a preliminarily bending mold, for pressing the glass sheet, b) a unit including a suction chamber disposed under the preliminarily bending supporting-frame and an air sucker communicating with the suction chamber, c) a heater for heating at least one portion of the glass sheet put on the preliminarily bending supporting-frame, and d) a unit including a plurality of ring elements forming the preliminarily bending supporting-frame and a driving device for vertically moving at least one of the ring elements.",
    "8. The apparatus according to claim 5, wherein the finally bending mold and/or the preliminarily bending mold has a plurality of apertures formed in a bending surface thereof, whereby the glass sheet is bent by sucking air through the apertures after the glass sheet is pressed.",
    "9. The apparatus according to claim 5, wherein the preliminarily bending unit and the finally bending unit are disposed in a heating furnace.",
    "10. The apparatus according to claim 5, further comprising a roller conveyor for conveying the heated and softened glass sheet, a floating unit disposed at a most downstream portion of the roller conveyor in order that the glass sheet conveyed by the roller conveyor is floated by injected air, a flat mold for holding the floated glass sheet without contact with the glass sheet, and a positioner for adjusting a position of the glass sheet with respect to the flat mold."
  ],
  "cpc": [
    "C03B 23/0305",
    "C03B 2225/02",
    "C03B 23/03",
    "C03B 23/0357",
    "C03B 35/145",
    "C03B 35/202",
    "Y02P 40/57"
  ],
  "assignees": [
    "ASAHI GLASS CO LTD"
  ],
  "filing_date": "2004-12-22",
  "publication_date": "2005-06-30",
  "priority_date": "2003-12-26",
  "application_number": "US-1796804-A",
  "family_id": "34567560",
  "citations": [
    "US2007039354A1",
    "US3088300A",
    "US5330550A",
    "US6082141A",
    "US6158247A",
    "US7401476B2"
  ]
}