US4704081A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Device for shaping synthetic resins
Assignee: Roehm GmbH Darmstadt
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Filing: 1986-04-23
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Granted: 1987-11-03
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Expires: 2006-04-23
Abstract
Abstract Molds or auxiliary molds for thermoforming a synthetic resin, said molds having a rigid main part connected surface-to-surface to an elastic layer having a smooth, continuous, matte surface which is more elastic than a softened resin with which it is to be contacted; devices for thermoforming comprising one or more of such molds; methods for thermoforming employing such molds and devices.
Inventors
- 👤 Horst Puehler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 12:08
CPC Classifications
B; B29; B29C; B29C51/00; B29C51/04; B29C51/06; B29C51/26; B29C51/10; B29K; B29K2033/00; B29K2033/04; B29K2995/00; B29K2995/0018; B29K2995/0022
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
148 words
A device for thermoforming a thermoelastically softened sheet of synthetic resin, said device comprising a tensioning frame for holding said softened sheet at the edges thereof, means for altering gas pressure on at least one side of said tensioning frame and softened sheet and, on the other side of said tensioning frame and softened sheet, first mold means comprising an elastic layer having a smooth and continuous matte surface adaptable to be brought into molding contact with said softened resin sheet, said elastic layer being more elastic than said softened sheet and being supported by a rigid base layer, resistant to deformation when said mold is brought into molding contact with said softened sheet, which base layer is affixed to said elastic layer in surface-to-surface relationship at least at those points at which said mold and softened sheet are brought into molding contact which deforms said softened sheet.
Claim 2
Independent Claim
148 words
A device for thermoforming a thermoelastically softened sheet of synthetic resin, said device comprising a tensioning frame for holding said softened sheet at the edges thereof, means for altering gas pressure on at least one side of said tensioning frame and softened sheet and, on the other side of said tensioning frame and softened sheet, first mold means comprising an elastic layer having a smooth and continuous matte surface adaptable to be brought into molding contact with said softened resin sheet, said elastic layer being more elastic than said softened sheet and being supported by a rigid base layer, resistant to deformation when said mold is brought into molding contact with said softened sheet, which base layer is affixed to said elastic layer in surface-to-surface relationship at least at those points at which said mold and softened sheet are brought into molding contact which deforms said softened sheet.
Claim 3
Dependent Claim
38 words
A device as in claim 1 additionally comprising moveable mold means on the same side of said tensioning frame as said gas pressure altering means and capable of moving through said tensioning frame toward said first mold means.
Claim 4
Dependent Claim
24 words
A device as in claim 1 wherein said first mold means additionally comprise a heat-insulating layer between said elastic layer and said base layer.
Claim 5
Dependent Claim
14 words
A device as in claim 3 wherein said heat-insulating layer is a foam layer.
Claim 6
Dependent Claim
24 words
A device as in claim 1 wherein said elastic layer is of a material having a share hardness less than 80° at 20° C.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-11-02 | 1991-05-04 | 1991-11-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-11-02 | 1995-05-04 | 1995-11-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-11-02 | 1999-05-04 | 1999-11-03 | $7700.00 | Window Closed / Lapsed |