US3949905A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Device for the production of articles with a compact smooth skin and a cellular core from polymer materials
Assignee: Institute of Metal Science, Equipment and Technologies
•
Filing: 1974-06-05
•
Granted: 1976-04-13
•
Expires: 1994-06-05
Abstract
Abstract An apparatus for the production of articles with a compact smooth skin and a cellular core from polymer materials, which contain blowing agents, by injection molding or extrusion wherein the apparatus contains an electric heating element within a channel through which the polymeric material is passed.
Inventors
- 👤 Ivan Dimov Nikolov
- 👤 Stefan Georgiev Semerdjiev
- 👤 Dragan Iliev Nenov
- 👤 Nikolay Tihomirov Popov
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 09:30
CPC Classifications
B; B29; B29C; B29C44/00; B29C44/02; B29C44/04; B29C44/0407; B29C44/34; B29C44/36; B29C44/46; B29C44/50; B29C45/00; B29C45/17; B29C45/72; B29C45/74; B29C48/00; B29C48/25; B29C48/78; B29C48/80; B29C48/802; B29C48/86; B29C48/865; B29C48/03; B29K; B29K2995/00; B29K2995/0037; B29K2995/0072; B29K2995/0073
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
155 words
An apparatus for the injection molding of an article with a compact smooth skin and a cellular core which comprises: a. a nozzle comprised of a housing and a tip mounted in front of said housing, said housing and said tip forming an axial passage running throughout their combined length; b. an elongated electric heating element located co-axially within and throughout the passage; c. means for electrically insulating said housing from said tip; d. means for forcing a thermoplastic molding material through said passage, said element being connected at one end to said tip and at the other end to said housing; and e. a source of electric current connected across said tip and said housing for supplying current to said electric heating element, said tip having an annular flange, said insulating means including a pair of insulating rings flanking said flange and a nut engaging one of said rings and threaded onto said housing.
Claim 2
Independent Claim
155 words
An apparatus for the injection molding of an article with a compact smooth skin and a cellular core which comprises: a. a nozzle comprised of a housing and a tip mounted in front of said housing, said housing and said tip forming an axial passage running throughout their combined length; b. an elongated electric heating element located co-axially within and throughout the passage; c. means for electrically insulating said housing from said tip; d. means for forcing a thermoplastic molding material through said passage, said element being connected at one end to said tip and at the other end to said housing; and e. a source of electric current connected across said tip and said housing for supplying current to said electric heating element, said tip having an annular flange, said insulating means including a pair of insulating rings flanking said flange and a nut engaging one of said rings and threaded onto said housing.
References Cited (Backward Citations)
CA658976A
Cited
US3077636A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-04-13 | 1979-10-13 | 1980-04-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-04-13 | 1983-10-13 | 1984-04-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-04-13 | 1987-10-13 | 1988-04-13 | $7700.00 | Window Closed / Lapsed |