Claims
- 1. A vacuum forming process for manufacturing a single piece panel, said process comprising the steps of:
- providing a plurality of plastic sheets of vacuum formable plastic;
- positioning said plurality of plastic sheets within a vacuum forming mold having a plurality of dies; each plastic sheet being positioned over a respective die;
- heating said plurality of plastic sheets at least to a temperature which said plurality of sheets are in a formable state;
- depositing each of said plurality of plastic sheets on said respective die;
- applying negative pressure through each of said dies, said negative pressure being of sufficient degree and applied in a manner whereby an attractive force is transmitted through each of said dies and attracts each of said plastic sheets onto said respective die;
- moving at least one of said plurality of dies in both an angular and linear direction such that a seam bond is produced between adjacent sheets of said plurality of plastic sheets;
- permitting said plurality of plastic sheets to cool to form said single piece panel with said seam bond maintaining a desired shape of said panel.
- 2. The vacuum forming process of claim 1 further comprising the step of providing additional heat to the area of said plurality of dies where said seam bond is to be made.
- 3. The vacuum forming process of claim 1 further comprising the step of applying positive pressure through each of said dies, said positive pressure being of sufficient degree and applied in a manner whereby said single piece panel is forced off of said plurality of dies.
- 4. The vacuum forming process of claim 1 further comprising the step of trimming the excess plastic material in the area of said seam bond.
- 5. A vacuum forming process for manufacturing a single piece panel, said process comprising the steps of:
- providing a single piece plastic sheet of vacuum formable plastic having at least one seam, each seam joining adjacent sheets of vacuum formable plastic;
- positioning said single plastic sheet within a vacuum forming mold having a plurality of dies, said single plastic sheet positioned such that each of said seams is positioned between adjacent dies of said plurality of dies;
- heating said single plastic sheet at least to a temperature at which said single plastic sheet is in a formable state;
- depositing said single plastic sheet on said plurality of dies such that each of said seams is positioned between adjacent dies of said plurality of dies;
- applying negative pressure through each of said dies, said negative pressure being of sufficient degree and applied in a manner whereby an attractive force is transmitted through each of said dies and attracts said single plastic sheet onto said plurality of dies;
- moving at least one of said plurality of dies in both an angular and linear direction to a position adjacent another of said plurality of dies such that a seam bond is produced between said adjacent sheets of vacuum formable plastic;
- permitting said plastic sheet to cool to form said single piece panel with said seam bond maintaining a desired shade of said panel.
- 6. The vacuum forming process of claim 5 further comprising the steps of:
- providing a plurality of plastic sheets of vacuum formable plastic;
- attaching adjacent plastic sheets of said plurality of plastic sheet together to form said single plastic sheet.
- 7. The vacuum forming process of claim 5 further comprising the step of providing additional heat to the area of said plurality of dies where said seam bond is to be made.
- 8. The vacuum forming process of claim 5 further comprising the step of applying positive pressure through each of said dies, said positive pressure being of sufficient degree and applied in a manner whereby said single piece panel is forced off of said plurality of dies.
- 9. The vacuum forming process of claim 5 further comprising the step of trimming the excess plastic material in the area of said seam bond.
- 10. The vacuum forming process of claim 5 further comprising the step of forming said single plastic sheet into a preform shape by applying a negative pressure between said single plastic sheet and an upper platen of said vacuum forming mold.
Parent Case Info
This is a division of United States patent application Ser. No. 08/062,616, filed May 11, 1993 now U.S. Pat. No. 5,401,355.
US Referenced Citations (20)
Foreign Referenced Citations (3)
Number |
Date |
Country |
0502621A1 |
Sep 1992 |
EPX |
2017552 |
Nov 1970 |
DEX |
2239837A |
Jul 1991 |
GBX |
Non-Patent Literature Citations (1)
Entry |
Plastics Engineering Handbook, Fourth Edition, p. 280, 1976. |
Divisions (1)
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Number |
Date |
Country |
Parent |
62616 |
May 1993 |
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