US3685930A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for continuously molding sheet material
Assignee: Kimberly Clark Corp
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Filing: 1970-05-27
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Granted: 1972-08-22
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Expires: 1990-05-27
Abstract
Abstract Apparatus is disclosed for producing molded sheet material. An endless belt-type mold is entrained over rolls, providing an upper run and a catenary. Molten thermoplastic material is extruded onto the upper run and caused to assume the configuration of the belt mold by the action of vacuum applied from beneath the belt before the molten material solidifies. The molded sheet material is stripped from the belt mold near the end of the upper run, and apparatus is provided fro efficiently cooling the catenary of the belt mold before molten material is applied again.
Inventors
- 👤 Leonard P Davis
- 👤 Robert M Elliott
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 11:02
CPC Classifications
B; B29; B29C; B29C51/00; B29C51/18; B29C51/20; B29C51/24; B29C53/00; B29C53/22; B29C53/24
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
181 words
Apparatus for continuously molding sheet material comprising, in combination a. an endless, flexible belt mold having an irregular molding surface integrally formed therein and a plurality of openings in depressed areas thereof, b. means for supporting and advancing said belt mold in a position defining an upper run and a catenary, c. a film die adapted to extrude a molten curtain of thermoplastic material onto the upper run of said belt mold, d. means for applying a vacuum to the underside of the belt to communicate with the openings in said belt at a position downstream from said extruder, e. means for withdrawing molded sheet material from the end of the upper run, and f. means for cooling said belt mold over at least a portion of its catenary including an air distribution chamber having an upper side formed of a nozzle plate, a series of generally transverse slits formed in said nozzle plate for directing air in a direction generally perpendicular to said belt mold, said nozzle plate conforming generally to the catenary of the lower run of said belt.
Claim 2
Dependent Claim
181 words
Apparatus for continuously molding sheet material comprising, in combination a. an endless, flexible belt mold having an irregular molding surface integrally formed therein and a plurality of openings in depressed areas thereof, b. means for supporting and advancing said belt mold in a position defining an upper run and a catenary, c. a film die adapted to extrude a molten curtain of thermoplastic material onto the upper run of said belt mold, d. means for applying a vacuum to the underside of the belt to communicate with the openings in said belt at a position downstream from said extruder, e. means for withdrawing molded sheet material from the end of the upper run, and f. means for cooling said belt mold over at least a portion of its catenary including an air distribution chamber having an upper side formed of a nozzle plate, a series of generally transverse slits formed in said nozzle plate for directing air in a direction generally perpendicular to said belt mold, said nozzle plate conforming generally to the catenary of the lower run of said belt.
Claim 3
Dependent Claim
23 words
Apparatus according to claim 1 in which said irregular molding surface includes portions extending generally perpendicular to the plane of the belt mold.
Claim 4
Dependent Claim
37 words
Apparatus according to claim 1 in which said air distribution chamber extends over a major portion of the length of the catenary of said belt mold and the nozzles extend substantially the width of the belt mold.
Claim 5
Dependent Claim
26 words
Apparatus according to claim 1 in which each of the nozzles is located between three-eighths inch and 1 1/2 inches from the catenary of said belt.
Claim 6
Dependent Claim
48 words
Apparatus according to claim 1 which includes a catch basin positioned below the lower run of said belt mold and under said extruder, and said extruder and catch basin being movable relative to said belt mold whereby molten thermoplastic material may be extruded directly into said catch basin.
References Cited (Backward Citations)
US1157149A
Cited
US3099043A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-08-22 | 1976-02-21 | 1976-08-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-22 | 1980-02-21 | 1980-08-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-22 | 1984-02-21 | 1984-08-22 | $7700.00 | Window Closed / Lapsed |