US4014737A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of molding preform having 600% by weight water
Assignee: Individual
•
Filing: 1975-05-19
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Granted: 1977-03-29
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Expires: 1995-05-19
Abstract
Abstract A molded cellulosic article, such as a loudspeaker cone, is formed without an intermediate drying step by first forming a pre-form having 600 - 900% water on a water pervious wire net, inserting the pre-form directly into a hot press, and drying the pre-form to less than about 5% by weight water in the hot press at a pressure less than about 400 psi and at a temperature of 400° - 450° F.
Inventors
- 👤 Robert M. Brennan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 13:49
CPC Classifications
D; D21; D21J; D21J5/00; D21J3/00; D21J3/12
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
171 words
A method of forming a molded cellulosic article comprising forming a pre-form comprising a wet layer of cellulosic fibers, having at least about 600% by weight water, on a water-pervious wire net by contacting the wire net with a water slurry of cellulosic fibers and drawing the fibers onto the wire net by suction through said wire net. disposing the pre-form having at least about 600% by weight while water on said wire net, onto a first die surface of a mold, contacting the pre-form, having at least about 600% by weight water, with a second die surface of said mold, and drying the pre-form having at least about 600% by weight water to less than about 5% by weight water in a heated press by pressing said wet layer of cellulosic fibers on said wire net in said heated press between said die surfaces at a pressure less than about 400 p.s.i., while allowing resulting steam to escape from said mold through said wire net and through said cellulosic fibers.
Claim 2
Independent Claim
171 words
A method of forming a molded cellulosic article comprising forming a pre-form comprising a wet layer of cellulosic fibers, having at least about 600% by weight water, on a water-pervious wire net by contacting the wire net with a water slurry of cellulosic fibers and drawing the fibers onto the wire net by suction through said wire net. disposing the pre-form having at least about 600% by weight while water on said wire net, onto a first die surface of a mold, contacting the pre-form, having at least about 600% by weight water, with a second die surface of said mold, and drying the pre-form having at least about 600% by weight water to less than about 5% by weight water in a heated press by pressing said wet layer of cellulosic fibers on said wire net in said heated press between said die surfaces at a pressure less than about 400 p.s.i., while allowing resulting steam to escape from said mold through said wire net and through said cellulosic fibers.
Claim 3
Dependent Claim
24 words
A method as defined in claim 1 wherein at least one of the mold die surfaces is heated to a temperature of 400°-450° F.
Claim 4
Dependent Claim
20 words
A method as defined in claim 2 wherein the preform is pressed at a pressure of 100 - 350 psi.
Claim 5
Dependent Claim
19 words
A method as defined in claim 3 wherein the preform is pressed at a pressure of about 150 psi.
Claim 6
Dependent Claim
27 words
A method as defined in claim 1 wherein the wet layer of cellulosic fibers contains at least 50% fibers having a length in excess of 1.0 mm.
Claim 7
Dependent Claim
24 words
A method as defined in claim 5 wherein the pulp slurry contains more than 70% fibers having a length in excess of 1.0 mm.
Claim 8
Dependent Claim
25 words
A method as defined in claim 1 wherein the wire net is shaped to substantially conform to the shape of the dryed, molded cellulosic article.
Claim 9
Dependent Claim
21 words
A method as defined in claim 7 wherein the wire net forms the shape of a vibration plate for a loudspeaker.
Claim 10
Independent Claim
165 words
A method of forming a molded cellulosic article comprising forming a pre-form comprising a wet layer of cellulosic fibers, having at least 600% by weight water, on a water-pervious support means by contacting the support means with a water slurry of cellulosic fibers and drawing the fibers onto the support by suction through said water-pervious support; disposing the pre-form comprising cellulosic fibers having at least 600% by weight water while on the water-pervious support means, onto a first die surface of a mold, contacting the pre-form comprising cellulosic fibes having at least 600% by weight water on said water-pervious support means, with a second die surface of said mold, and heating at least one of said die surfaces and pressing said wet layer of cellulosic fibers, having at least 600% by weight water, between said die surfaces at a pressure less than about 400 psi, while allowing resulting steam to escape from said mold through said water-pervious support means, to substantially dry said cellulosic fibers.
Claim 11
Independent Claim
165 words
A method of forming a molded cellulosic article comprising forming a pre-form comprising a wet layer of cellulosic fibers, having at least 600% by weight water, on a water-pervious support means by contacting the support means with a water slurry of cellulosic fibers and drawing the fibers onto the support by suction through said water-pervious support; disposing the pre-form comprising cellulosic fibers having at least 600% by weight water while on the water-pervious support means, onto a first die surface of a mold, contacting the pre-form comprising cellulosic fibes having at least 600% by weight water on said water-pervious support means, with a second die surface of said mold, and heating at least one of said die surfaces and pressing said wet layer of cellulosic fibers, having at least 600% by weight water, between said die surfaces at a pressure less than about 400 psi, while allowing resulting steam to escape from said mold through said water-pervious support means, to substantially dry said cellulosic fibers.
Claim 12
Dependent Claim
27 words
A method as defined in claim 9 including heating at least one of the mold die surfaces to a temperature in the range of about 400°-450° F.
Claim 13
Dependent Claim
21 words
A method as defined in claim 9 including pressing the pre-form at a pressure in the range of about 100-350 psi.
Claim 14
Dependent Claim
27 words
A method as defined in claim 9 wherein the wet layer of cellulosic fibers comprises more than 50% fibers having a length in excess of 1.0 mm.
Claim 15
Dependent Claim
27 words
A method as defined in claim 12 wherein the wet layer of cellulosic fibers comprises more than 70% fibers having a length in excess of 1.0 mm.
Claim 16
Dependent Claim
22 words
A method as defined in claim 9 wherein the water-pervious support means forms the shape of a vibration plate for a loudspeaker.
Claim 17
Independent Claim
193 words
A method of forming a molded article comprising forming a pre-form comprising a wet layer of cellulosic fibers, having at least 600% by weight water and having at least 50% fibers with a length of at least 1.0 mm., on a water-pervious support member; disposing the pre-form and support member onto a first die surface of a mold, while the pre-form contains at least 600% by weight water and at least 50% fibers with a length of at least 1.0 mm.; contacting the pre-form of cellulosic fibers, having at least 600% by weight water and having at least 50% fibers with a length of at least 1.0 mm., with a second die surface of said mold, and drying the pre-form of cellulosic fibers, having at least 600% by weight water and having at least 50% fibers with a length of at least 1.0 mm., in a heated press maintained at a pressure and for a period of time sufficient to remove substantially all of the water contained in the pre-form but insufficient to press the cellulosic fibers through the support member, such that steam generated in the heated press can laterally escape therefrom.
Claim 18
Independent Claim
193 words
A method of forming a molded article comprising forming a pre-form comprising a wet layer of cellulosic fibers, having at least 600% by weight water and having at least 50% fibers with a length of at least 1.0 mm., on a water-pervious support member; disposing the pre-form and support member onto a first die surface of a mold, while the pre-form contains at least 600% by weight water and at least 50% fibers with a length of at least 1.0 mm.; contacting the pre-form of cellulosic fibers, having at least 600% by weight water and having at least 50% fibers with a length of at least 1.0 mm., with a second die surface of said mold, and drying the pre-form of cellulosic fibers, having at least 600% by weight water and having at least 50% fibers with a length of at least 1.0 mm., in a heated press maintained at a pressure and for a period of time sufficient to remove substantially all of the water contained in the pre-form but insufficient to press the cellulosic fibers through the support member, such that steam generated in the heated press can laterally escape therefrom.
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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) | 1980-03-28 | 1980-09-27 | 1981-03-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-03-28 | 1984-09-27 | 1985-03-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-03-28 | 1988-09-27 | 1989-03-29 | $7700.00 | Window Closed / Lapsed |