Patent US3841822A successfully refreshed from Google Patents.
US3841822A
Expired / Lapsed
US
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Seamless article molding apparatus
Assignee: MOLDING TECHNOLOGY PARTNERS Ltd
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Filing: 1973-10-03
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Granted: 1974-10-15
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Expires: 1993-10-03
Abstract
Abstract Molding apparatus for molding articles without a seam or parting line even though the articles may have severe backdraft portions. The apparatus includes a one-piece flexible mold of relatively thick and self-supporting wall construction which is deformable by the application of fluid pressure differential to thereby release the finished article from the mold. One modification of the one-piece mold also has a thick radially extending flange which forms a seal with a vacuum pot when the mold is simply set in the pot.
Inventors
- 👤 R Putzer
- 👤 W Maurino
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 07:52
CPC Classifications
B; B29; B29C; B29C33/00; B29C33/44; B29C33/48; B29C33/50; B28; B28B; B28B7/00; B28B7/06; B28B7/10; B28B7/12; B29C33/38; B29C33/40; B29C43/00; B29C43/32; B29C43/36; B29C43/3642; B29C2043/3652; B29C33/0033; B29K; B29K2891/00; B29L; B29L2031/00; B29L2031/709; B29L2031/7096; B29L2031/7102
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
85 words
Apparatus for molding seamless articles comprising a generally hollow, one-piece elastomeric flexible mold having a side wall of sufficient thickness that it is self-supporting and supports the weight of the material when being poured therein without distortion of said mold, said mold side wall being of varying thickness thereby forming undercut back draft portions in said mold, means for injecting air pressure between said mold and the article therein to thereby cause expansion of said mold and permit removal of the article from the mold.
Claim 2
Dependent Claim
85 words
Apparatus for molding seamless articles comprising a generally hollow, one-piece elastomeric flexible mold having a side wall of sufficient thickness that it is self-supporting and supports the weight of the material when being poured therein without distortion of said mold, said mold side wall being of varying thickness thereby forming undercut back draft portions in said mold, means for injecting air pressure between said mold and the article therein to thereby cause expansion of said mold and permit removal of the article from the mold.
Claim 3
Dependent Claim
29 words
The apparatus set forth in claim 1 including a bottom wall connected to said side wall, and said means for injecting air pressure is located in said bottom wall.
References Cited (Backward Citations)
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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) | 1977-10-14 | 1978-04-15 | 1978-10-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-10-14 | 1982-04-15 | 1982-10-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-10-14 | 1986-04-15 | 1986-10-15 | $7700.00 | Window Closed / Lapsed |