US3830616A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Means for molding articles of thermoplastic sheet materials
Assignee: Coleman Cable and Wire Co
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Filing: 1972-07-03
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Granted: 1974-08-20
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Expires: 1992-07-03
Abstract
Abstract Method and apparatus for molding three dimensional articles of thermoplastic sheet material which after molding will withstand the high temperatures of autoclaving for sterilization in hospital use without distortion. Molding is accomplished by providing a low mass mold made of sheet metal which has low heat sink characteristics and is adapted to providing a high degree of temperature uniformity by being made of substantially uniform thickness high thermal conductivity material heated by convection hot air means for a preselected dwell time with the consequent attainment of thermal stability during formation of the article.
Inventors
- 👤 C Hawkins
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 15:12
CPC Classifications
B; B29; B29C; B29C51/00; B29C51/26; B29C51/42; B29C51/426; B29C51/428
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
111 words
Apparatus for molding thermo-formable sheet material into three dimensional articles comprising, a mold having a cavity on one side conforming in shape to the article to be formed, means for flowing heated gas in direct communication with said mold on the side of said mold opposite said cavity effective to heat said mold by convection to a preselected temperature substantially throughout, means for bringing and holding said sheet material in heat conductive comMunication with the heated cavity surface of said mold as convection heat is continued to be supplied to said opposite side for a predetermined dwell period for dimensional stability, and means for forcefully cooling the article in said mold.
Claim 2
Dependent Claim
111 words
Apparatus for molding thermo-formable sheet material into three dimensional articles comprising, a mold having a cavity on one side conforming in shape to the article to be formed, means for flowing heated gas in direct communication with said mold on the side of said mold opposite said cavity effective to heat said mold by convection to a preselected temperature substantially throughout, means for bringing and holding said sheet material in heat conductive comMunication with the heated cavity surface of said mold as convection heat is continued to be supplied to said opposite side for a predetermined dwell period for dimensional stability, and means for forcefully cooling the article in said mold.
Claim 3
Dependent Claim
20 words
Apparatus according to claim 1, wherein the mold is of uniform thickness and made of material of high thermal conductivity.
Claim 4
Dependent Claim
22 words
Apparatus according to claim 2, wherein the mold is made of sheet metal selected from the group of copper, aluminum and silver.
Claim 5
Dependent Claim
45 words
Apparatus according to claim 1, wherein the means for bringing and holding said sheet material in communication with the heated cavity surface of the mold comprises pneumatic negative pressure means connected to at least one aperture suitably located in the cavity surface of said mold.
Claim 6
Dependent Claim
50 words
Apparatus according to claim 4, wherein the means for bringing and holding said sheet material in communication with the heated cavity surface of the mold includes a clamping means for securing said sheet meaterial over the mold cavity in the region of the perimeter of the article to be formed.
Claim 7
Dependent Claim
33 words
Apparatus according to claim 1, wherein the means for forcefully cooling the article in said mold comprises means for blowing convection cooling gas at the major surface of the mold opposite said cavity.
Claim 8
Dependent Claim
21 words
Apparatus according to claim 6, wherein the convection cooling means includes means for cooling the convection cooling gas below atmospheric temperature.
References Cited (Backward Citations)
US2496014A
Cited
US2694227A
Cited
US2926385A
Cited
US3041669A
Cited
US3137747A
Cited
US3258813A
Cited
US3496143A
Cited
US3368243A
Cited
US3476377A
Cited
US3646190A
Cited
US3687594A
Cited
US3737496A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-08-19 | 1978-02-18 | 1978-08-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-08-19 | 1982-02-18 | 1982-08-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-08-19 | 1986-02-18 | 1986-08-20 | $7700.00 | Window Closed / Lapsed |