US3218375A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Molding of foam plastic articles
Assignee: Individual
•
Filing: 1962-12-21
•
Granted: 1965-11-16
•
Expires: 1982-12-21
Abstract
No abstract record available.
Inventors
- 👤 Hardwick Eugene Russell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 09:32
CPC Classifications
B; B29; B29C; B29C44/00; B29C44/34; B29C44/36; B29C44/38; B29C44/42; B29C44/421; B29C44/02; B29C44/04; B29C44/0407; Y; Y10; Y10S; Y10S264/00; Y10S264/83
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
134 words
IN A METHOD FOR THE MANUFACTURE OF AN ARTICLE HAVING A FOAM STRUCTURE, THE STEPS COMPRISING: PROVIDING WITHIN A FIXED VOLUME MOLD CAVITY A MELT OF A GAS-EXPANSIBLE PLASTIC MATERIAL CONTAINING A BLOWING AGENT MIX THEREIN, SAID MELT FILLING THE CAVITY AND MAINTAINED UNDER PRESSURE TO HOLD THE BLOWING AGENT IN A REDUCED VOLUME FORM; COOLING THE CAVITY WHILE MAINTAINING THE MELT UNDER AN ELEVATED PRESSURE WITHIN SAID CAVITY TO FORM A HARDENED SHELL OF PLASTIC MATERIAL ABOUT THE MELT; AND THEREAFTER REDUCING THE PRESSURE ON THE MELT WHILE MAINTAINING THE VOLUME OF THE CAVITY CONSTANT BY PROVIDING AN EGRESS FOR MELT FROM THE MOLD CAVITY AND CAUSING THE MELT TO BE EXPANDED BY THE BLOWING AGENT INTO A FOAM STRUCTURE WITH THE EXCESS FOAM MATERIAL BEING REMOVED FROM THE CAVITY THROUGH SAID EGRESS.
Claim 2
Dependent Claim
134 words
IN A METHOD FOR THE MANUFACTURE OF AN ARTICLE HAVING A FOAM STRUCTURE, THE STEPS COMPRISING: PROVIDING WITHIN A FIXED VOLUME MOLD CAVITY A MELT OF A GAS-EXPANSIBLE PLASTIC MATERIAL CONTAINING A BLOWING AGENT MIX THEREIN, SAID MELT FILLING THE CAVITY AND MAINTAINED UNDER PRESSURE TO HOLD THE BLOWING AGENT IN A REDUCED VOLUME FORM; COOLING THE CAVITY WHILE MAINTAINING THE MELT UNDER AN ELEVATED PRESSURE WITHIN SAID CAVITY TO FORM A HARDENED SHELL OF PLASTIC MATERIAL ABOUT THE MELT; AND THEREAFTER REDUCING THE PRESSURE ON THE MELT WHILE MAINTAINING THE VOLUME OF THE CAVITY CONSTANT BY PROVIDING AN EGRESS FOR MELT FROM THE MOLD CAVITY AND CAUSING THE MELT TO BE EXPANDED BY THE BLOWING AGENT INTO A FOAM STRUCTURE WITH THE EXCESS FOAM MATERIAL BEING REMOVED FROM THE CAVITY THROUGH SAID EGRESS.
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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) | 1968-11-15 | 1969-05-17 | 1969-11-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-11-15 | 1973-05-17 | 1973-11-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-11-15 | 1977-05-17 | 1977-11-16 | $7700.00 | Window Closed / Lapsed |