US4243368A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for making a stress-free plastic article
Assignee: Individual
•
Filing: 1978-07-31
•
Granted: 1981-01-06
•
Expires: 1998-07-31
Abstract
Abstract Disclosed is a method and apparatus for making stress free plastic articles from plastic particles such as powder utilizing heat and pressure in which a quantity of plastic particles is supplied to a first member, a flexible diaphragm is disposed in opposed relationship to said first member with said plastic particles therebetween, a microporous air release means is positioned between said plastic particles and said flexible diaphragm, a fluid-like pressure is applied to said diaphragm to cause said diaphragm to apply an even fluid-like pressure through said air release means to said plastic particles, heat is applied to said plastic particles while under said fluid-like pressure and any entrapped gases between the particles is vented by means of the air release means. The pressure and heat are controlled to effect a consolidation of the plastic particles into the article. A second diaphragm may be used on the opposite side of said first diaphragm and either one or both of said diaphragms may be a sealed envelope to which fluid pressure is applied. The plastic article produced by the method is substantially free of all stresses.
Inventors
- 👤 Armen Garabedian
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 20:01
CPC Classifications
B; B29; B29C; B29C66/00; B29C66/01; B29C66/343; B29C37/00; B29C37/006; B29C43/00; B29C43/006; B29C43/02; B29C43/10; B29C43/12; B29C43/32; B29C43/36; B29C43/3642; B29C65/00; B29C65/02; B29C65/18; B29C65/24; B29C65/245; B29C65/30; B29C65/305; B29C66/001; B29C66/05; B29C66/10; B29C66/11; B29C66/112; B29C66/1122; B29C66/40; B29C66/41; B29C66/45; B29C66/47; B29C66/472; B29C66/80; B29C66/81; B29C66/814; B29C66/8145; B29C66/81455; B29C66/816; B29C66/8163; B29C66/82; B29C66/826; B29C66/8266; B29C66/82661; B29C66/83; B29C66/832; B29C66/8322; B29C66/83221; B29C33/00; B29C33/56; B29C33/68; B29C66/70; B29C66/71; B29C66/712; B29C66/812; B29C66/8122; B29C66/8126; B29C66/81261; B29K; B29K2023/00; B29K2023/04; B29K2023/06; B29K2023/0658; B29K2023/0683; B29K2027/00; B29K2027/06; B29K2105/00; B29K2105/25; B29K2105/251; B29K2105/253; B29K2105/256; B29L; B29L2031/00; B29L2031/709; Y; Y10; Y10S; Y10S425/00; Y10S425/06; Y10S425/808; Y10S425/812
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
198 words
Apparatus for producing a plastic sheet from plastic material in comminuted form in which the plastic sheet has on a major face thereof the characteristics of one surface of a master layer, comprising a master layer means on the surface of which there is disposed a layer of plastic material in comminuted form, a micro-porous parting sheet disposed over said comminuted plastic material, an air releasing wire screen sheet disposed over said micro-porous parting sheet, the arrangement thereby forming a multiple layer sandwich which includes said wire screen sheet, said micro-porous parting sheet, said comminuted plastic material, and said master layer means, two flexible spaced diaphragm means between which said multiple layer sandwich is disposed, melting means for heating said plastic material as the latter is disposed in said multiple layer sandwich array between said spaced diaphragm means, and means for applying a fluid pressure to said diaphragm means to evenly impress a fluid-like pressure to said multiple layer sandwich with a force sufficient to cause the melted plastic material to fuse to a coherent mass defining a plastic sheet as said major face takes on the characteristics of said one surface of the juxtaposed master layer means.
Claim 2
Dependent Claim
198 words
Apparatus for producing a plastic sheet from plastic material in comminuted form in which the plastic sheet has on a major face thereof the characteristics of one surface of a master layer, comprising a master layer means on the surface of which there is disposed a layer of plastic material in comminuted form, a micro-porous parting sheet disposed over said comminuted plastic material, an air releasing wire screen sheet disposed over said micro-porous parting sheet, the arrangement thereby forming a multiple layer sandwich which includes said wire screen sheet, said micro-porous parting sheet, said comminuted plastic material, and said master layer means, two flexible spaced diaphragm means between which said multiple layer sandwich is disposed, melting means for heating said plastic material as the latter is disposed in said multiple layer sandwich array between said spaced diaphragm means, and means for applying a fluid pressure to said diaphragm means to evenly impress a fluid-like pressure to said multiple layer sandwich with a force sufficient to cause the melted plastic material to fuse to a coherent mass defining a plastic sheet as said major face takes on the characteristics of said one surface of the juxtaposed master layer means.
Claim 3
Dependent Claim
41 words
Apparatus according to claim 1 wherein each of said diaphragm means has a peripheral resilient gasket, and pressure members for forcing said gaskets into sealing relationship with one another to thereby seal said multiple layer sandwich between said two diaphragm means.
Claim 4
Dependent Claim
41 words
Apparatus according to claim 1 wherein each of said diaphragm means comprises a closed diaphragm element having an internal fluid space therein, said fluid pressure applying means being operable to apply fluid under pressure to each of said closed diaphragm elements.
Claim 5
Dependent Claim
14 words
Apparatus according to claim 1 wherein said flexible diaphragm means are made of metal.
Claim 6
Dependent Claim
14 words
Apparatus according to claim 1 wherein said master layer means is made of glass.
Claim 7
Dependent Claim
15 words
Apparatus according to claim 1 wherein said micro-porous parting sheet is a polytetrafluoroethylene-coated glass fabric.
Claim 8
Dependent Claim
17 words
Apparatus according to claim 1 further comprising movable support means on which said diaphragm means are mounted.
Claim 9
Dependent Claim
17 words
Apparatus according to claim 1 further comprising movable support means on which said heating means are mounted.
References Cited (Backward Citations)
US1311342A
Cited
CA678203A
Cited
US635917A
Cited
US1190072A
Cited
US1909444A
Cited
US1725454A
Cited
US1884529A
Cited
GB369028A
Cited
US2196577A
Cited
US2268477A
Cited
US2467322A
Cited
US2363107A
Cited
US2456093A
Cited
US2367779A
Cited
US2459295A
Cited
US2447415A
Cited
US2620289A
Cited
US2468629A
Cited
US2524932A
Cited
US2480851A
Cited
US2565949A
Cited
USRE23572E
Cited
US2698273A
Cited
US2654901A
Cited
US2751321A
Cited
US2711985A
Cited
US2851730A
Cited
US2794940A
Cited
US2743761A
Cited
US2731654A
Cited
US2929109A
Cited
US2936261A
Cited
US2833686A
Cited
US2965527A
Cited
US2960425A
Cited
GB822609A
Cited
US2978008A
Cited
US2911678A
Cited
US3067507A
Cited
US2960147A
Cited
DE1112894B
Cited
US3090717A
Cited
US3297805A
Cited
US3158089A
Cited
US3146143A
Cited
US3130101A
Cited
US3202745A
Cited
US3228330A
Cited
GB1045279A
Cited
US3247041A
Cited
GB1022156A
Cited
GB1039898A
Cited
US3383265A
Cited
US3493451A
Cited
US3686383A
Cited
US3769133A
Cited
US3694129A
Cited
US4104101A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-01-06 | 1984-07-07 | 1985-01-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-01-06 | 1988-07-07 | 1989-01-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-01-06 | 1992-07-07 | 1993-01-06 | $7700.00 | Window Closed / Lapsed |