US3709645A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Extrusion head
Assignee: Dunlap Holdings Ltd
•
Filing: 1970-06-22
•
Granted: 1973-01-09
•
Expires: 1990-06-22
Abstract
Abstract An extruder head having a housing, extruder core and core holder in which the limiting surfaces of the exit channel are formed on the extruder core and on the core holder respectively. The construction of the head can be extremely compact and enables extrusions of predetermined wall thickness to be obtained, of which the following is a specification.
Inventors
- 👤 H Mraz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 10:59
CPC Classifications
B; B29; B29C; B29C48/00; B29C48/25; B29C48/30; B29C48/32; B29C48/03; B29C48/09; B29C48/10; B29C48/12; B29C48/07; B29C48/08
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
143 words
An extruder head for an extruder for production of extrusions of predetermined wall thickness comprising a housing; an extruder core, an extruder core holder on which the core is carried within the housing to secure the extruder core in the housing there being locating surfaces on the core and the core holder to facilitate accurate positioning of the core on the core holder; an exit channel, the first limiting surface of the exit channel being formed on an annular component of the core and the second limiting surface of the exit channel being formed as an integral part of the extruder core holder, the core being secured on the core holder whereby the two can be removed from the housing as a single unit, the fitting of the core holder in the housing not affecting the accuracy of dimension of the exit channel.
Claim 2
Dependent Claim
143 words
An extruder head for an extruder for production of extrusions of predetermined wall thickness comprising a housing; an extruder core, an extruder core holder on which the core is carried within the housing to secure the extruder core in the housing there being locating surfaces on the core and the core holder to facilitate accurate positioning of the core on the core holder; an exit channel, the first limiting surface of the exit channel being formed on an annular component of the core and the second limiting surface of the exit channel being formed as an integral part of the extruder core holder, the core being secured on the core holder whereby the two can be removed from the housing as a single unit, the fitting of the core holder in the housing not affecting the accuracy of dimension of the exit channel.
Claim 3
Dependent Claim
45 words
An extruder head according to claim 1 in which the holder is provided with a series of cut-away openings, disposed in a ring and separated by webs, to permit flow of material to be extruded through the holder from the housing to the exit channel.
Claim 4
Dependent Claim
31 words
An extruder head according to claim 2 in which flattenings are formed on the extruder core opposite the webs to smooth the flow of material to be extruded from the openings.
References Cited (Backward Citations)
US1947202A
Cited
US2437625A
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US2592658A
Cited
US2499398A
Cited
FR1267258A
Cited
US3106746A
Cited
FR1319817A
Cited
US3461500A
Cited
US3432886A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-01-09 | 1976-07-10 | 1977-01-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-01-09 | 1980-07-10 | 1981-01-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-01-09 | 1984-07-10 | 1985-01-09 | $7700.00 | Window Closed / Lapsed |