US3776683A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for molding articles
Assignee: MOLDING TECHNOLOGY PARTNERS Ltd
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Filing: 1972-01-31
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Granted: 1973-12-04
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Expires: 1992-01-31
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
2026-11-03 00:03
CPC Classifications
B; B29; B29C; B29C39/00; B29C39/22; B29C39/42; B28; B28B; B28B13/00; B28B13/04; B28B13/06; B28B7/00; B28B7/06; B28B7/10; B28B7/12; B29C33/00; B29C33/0038; B29C33/38; B29C33/40; B29C33/44; B29C33/46; B29C33/48; B29C33/50; B29C39/02; B29C39/26; B29C43/00; B29C43/32; B29C43/36; B29C43/3642; B29C2043/3652; B29C33/0033; B29K; B29K2891/00; B29L; B29L2031/00; B29L2031/709; B29L2031/7096; B29L2031/7102; Y; Y10; Y10S; Y10S425/00; Y10S425/044; Y10S425/058
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
129 words
Apparatus for molding seamless articles comprising a generally hollow, one-piece distensible flexible mold having a thick and self-supporting, radially extending annular flange, said mold being of such wall thickness that it is self-supporting and supports the weight of the material poured therein without distortion of said mold, a vacuum pot having an upper edge, said pot being of such size so as to receive said mold therein with said flange resting on said pot edge to form a seal therewith, said mold and pot thus forming a sealed annular chamber therebetween, means for drawing a vacuum in said chamber whereby said mold distends and expands into said chamber and said flange cooperates with said pot edge to maintain said seal as said mold is retracted from an article therein.
Claim 2
Dependent Claim
129 words
Apparatus for molding seamless articles comprising a generally hollow, one-piece distensible flexible mold having a thick and self-supporting, radially extending annular flange, said mold being of such wall thickness that it is self-supporting and supports the weight of the material poured therein without distortion of said mold, a vacuum pot having an upper edge, said pot being of such size so as to receive said mold therein with said flange resting on said pot edge to form a seal therewith, said mold and pot thus forming a sealed annular chamber therebetween, means for drawing a vacuum in said chamber whereby said mold distends and expands into said chamber and said flange cooperates with said pot edge to maintain said seal as said mold is retracted from an article therein.
Claim 3
Dependent Claim
31 words
The apparatus as described in claim 1 further characterized in that said flange is of such strength and thickness that it supports the mold in hanging relationship on said pot edge.
Claim 4
Dependent Claim
55 words
The apparatus of claim 2 further characterized in that a rounded and smooth engagement is provided between the underside of said flange and said pot edge whereby when vacuum is applied to said pot, said mold is drawn downwardly into said pot and said flange is pulled against said edge in continuously sealing contact therewith.
Claim 5
Dependent Claim
55 words
The apparatus of claim 1 further characterized in that a rounded and smooth engagement is provided between the underside of said flange and said pot edge whereby when vacuum is applied to said pot, said mold is drawn downwardly into said pot and said flange is pulled against said edge in continuously sealing contact therewith.
Claim 6
Dependent Claim
19 words
The apparatus set forth in claim 1 further characterized in that said mold is made of polysulphide synthetic rubber.
Claim 7
Dependent Claim
14 words
The apparatus set forth in Claim 1 wherein said walls are of varying thickness.
Claim 8
Dependent Claim
159 words
Molding apparatus for seamless articles and comprising; a generally hollow, one-piece distensible flexible mold having a side wall of such thickness that it is self-supporting and supports the weight of the material poured therein without distortion of said mold, said mold also having a thick and radially extending annular flange adjacent the upper end thereof, said flange having a smooth lower surface; a vacuum pot having an open upper end defined by an upper edge, said pot being of such size so as to receive said mold through said open end with said flange lower surface resting on said pot edge to thereby form a seal therewith and defining a sealed annular chamber between said pot and mold; and means for drawing a vacuum in said chamber whereby said mold expands generally radially into said chamber and said flange is drawn tightly against said pot edge due to said vacuum and maintains said seal as said mold is expanded.
Claim 9
Dependent Claim
159 words
Molding apparatus for seamless articles and comprising; a generally hollow, one-piece distensible flexible mold having a side wall of such thickness that it is self-supporting and supports the weight of the material poured therein without distortion of said mold, said mold also having a thick and radially extending annular flange adjacent the upper end thereof, said flange having a smooth lower surface; a vacuum pot having an open upper end defined by an upper edge, said pot being of such size so as to receive said mold through said open end with said flange lower surface resting on said pot edge to thereby form a seal therewith and defining a sealed annular chamber between said pot and mold; and means for drawing a vacuum in said chamber whereby said mold expands generally radially into said chamber and said flange is drawn tightly against said pot edge due to said vacuum and maintains said seal as said mold is expanded.
Claim 10
Dependent Claim
200 words
Apparatus for molding a generally hollow and seamless article comprising a generally hollow, one-piece distensible flexible outer mold having a thick and self-supporting, radially extending annular flange, a one-piece distensible flexible inner mold inserted in said generally hollow outer mold and forming therewith an annular space into which hardenable material can be poured and which is of the configuration of the article to be made, said outer mold being of such wall thickness that it is self-supporting and supports the weight of the material poured therein without distortion of said outer mold, a vacuum pot having an upper edge, said pot being of such size so as to receive said outer mold therein with said flange resting on said pot edge to form a seal therewith, said outer mold and pot thus forming a sealed annular chamber therebetween, means for drawing a vacuum in said chamber and in said space whereby said outer mold distends and expands into said chamber and said flange cooperates with said pot edge to maintain said seal as said outer mold is retracted from an article therein, and whereby said inner mold collapses to permit its withdrawal from said article when the latter has hardened.
Claim 11
Dependent Claim
200 words
Apparatus for molding a generally hollow and seamless article comprising a generally hollow, one-piece distensible flexible outer mold having a thick and self-supporting, radially extending annular flange, a one-piece distensible flexible inner mold inserted in said generally hollow outer mold and forming therewith an annular space into which hardenable material can be poured and which is of the configuration of the article to be made, said outer mold being of such wall thickness that it is self-supporting and supports the weight of the material poured therein without distortion of said outer mold, a vacuum pot having an upper edge, said pot being of such size so as to receive said outer mold therein with said flange resting on said pot edge to form a seal therewith, said outer mold and pot thus forming a sealed annular chamber therebetween, means for drawing a vacuum in said chamber and in said space whereby said outer mold distends and expands into said chamber and said flange cooperates with said pot edge to maintain said seal as said outer mold is retracted from an article therein, and whereby said inner mold collapses to permit its withdrawal from said article when the latter has hardened.
Claim 12
Dependent Claim
32 words
The apparatus as described in claim 8 further characterized in that said flange is of such strength and thickness that it supports the outer mold in hanging relationship on said pot edge.
Claim 13
Dependent Claim
56 words
The apparatus of claim 9 further characterized in that a rounded and smooth engagement is provided between the underside of said flange and said pot edge whereby when vacuum is applied to said pot, said outer mold is drawn downwardly into said pot and said flange is pulled against said edge in continuously sealing contact therewith.
Claim 14
Dependent Claim
56 words
The apparatus of claim 8 further characterized in that a rounded and smooth engagement is provided between the underside of said flange and said pot edge whereby when vacuum is applied to said pot, said outer mold is drawn downwardly into said pot and said flange is pulled against said edge in continuously sealing contact therewith.
Claim 15
Dependent Claim
19 words
The apparatus set forth in claim 8 further characterized in that said mold is made of polysulphide synthetic rubber.
Claim 16
Dependent Claim
18 words
The apparatus set forth in claim 8 wherein said walls of said outer mold are of varying thickness.
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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) | 1976-12-03 | 1977-06-04 | 1977-12-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-12-03 | 1981-06-04 | 1981-12-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-12-03 | 1985-06-04 | 1985-12-04 | $7700.00 | Window Closed / Lapsed |