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US6294114B1 Expired / Lapsed US ⏱️ 0.0 years remaining

Triple sheet thermoforming apparatus, methods and articles

Assignee: Individual
•
Filing: 1999-08-20
•
Granted: 2001-09-25
•
Expires: 2019-08-20
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Abstract

Abstract A method of manufacturing a thermoplastic article including heating first and second thermoplastic sheets and conforming the first and second thermoplastic sheets to corresponding molds. The first and second thermoplastic are then joined to form a sheet subassembly. The method further includes heating a third thermoplastic sheet and conforming the third thermoplastic sheet to a corresponding mold. The third thermoplastic sheet is then joined to the sheet subassembly.

Inventors

  • 👤 Scott A. W. Muirhead

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-02 16:19
CPC Classifications
B; B29; B29C; B29C51/00; B29C51/16; B29C51/165; B29C51/26; B29C51/266; B29C51/267; B29C65/00; B29C65/02; B29C65/022; B29C65/028; B29C65/14; B29C65/1403; B29C65/1412; B29C65/78; B29C65/7858; B29C65/7861; B29C65/7864; B29C65/7879; B29C66/00; B29C66/01; B29C66/02; B29C66/024; B29C66/0242; B29C66/05; B29C66/10; B29C66/13; B29C66/131; B29C66/1312; B29C66/133; B29C66/50; B29C66/51; B29C66/54; B29C66/543; B29C66/545; B29C66/80; B29C66/83; B29C66/832; B29C66/8322; B29C66/83221; B65; B65D; B65D19/00; B65D19/0002; B65D19/0004; B65D19/0006; B65D19/0008; B65D19/001; B65D19/0012; B65D19/0014; B65D19/0018; B29C2791/00; B29C2791/001; B29C2791/004; B29C2791/006; B29C51/10; B29C51/12; B29C66/70; B29C66/71; B29C66/72; B29C66/725; B29C66/7252; B29C66/72521; B29C66/82; B29C66/824; B29C66/8242; B29L; B29L2031/00; B29L2031/712; B29L2031/7178; B65D2519/00; B65D2519/00004; B65D2519/00009; B65D2519/00014; B65D2519/00034; B65D2519/00049; B65D2519/00069; B65D2519/00084; B65D2519/00104; B65D2519/00119; B65D2519/00139; B65D2519/00258; B65D2519/00283; B65D2519/00288; B65D2519/00293; B65D2519/00303; B65D2519/00313; B65D2519/00318; B65D2519/00323; B65D2519/00328; B65D2519/00333; B65D2519/00338; B65D2519/00358; B65D2519/00398; B65D2519/00402; B65D2519/00407; B65D2519/00412; B65D2519/00432; B65D2519/00447; B65D2519/00547; B65D2519/00552; B65D2519/00557; B65D2519/00562; B65D2519/00736; B65D2519/00935; B65D2519/0094

Claims Analysis

Total Claims: 21
Claim 1
Independent Claim 257 words
A method for thermoforming a single article from three heat deformable thermoplastic sheets, the method comprising: releasably clamping three thermoplastic sheets to a frame; moving the three thermoplastic sheets on the frame through at least three ovens and heating the three thermoplastic sheets to a heat deformable temperature; moving the three heated sheets successively to a forming station on the frame; supporting in spaced apart overlying relation a first platen and a second platen on the forming station, and causing the platens to travel in opposed directions between open and closed positions; selectively positioning three molds on the first and second platens; selectively slidably moving a second one of the molds and a third one of the molds into and out of position on the second platen; moving the first and second platens in succession between the open and closed position to displace the three molds and to apply pressure to the three heated thermoplastic sheets in order to mold the sheets in a preselected configuration; moving one platen to compress a first one of the molded sheets against a second one of the molded sheets retained by the second platen in order to fuse together the two molded sheets to form a twin sheet molded article; and moving the platen retaining the twin sheet molded article into compression with the other platen retaining a third one of the molded sheets on the third mold in order to fuse together the twin sheet molded article and the third molded sheet to form a triple sheet molded article.
Claim 2
Independent Claim 257 words
A method for thermoforming a single article from three heat deformable thermoplastic sheets, the method comprising: releasably clamping three thermoplastic sheets to a frame; moving the three thermoplastic sheets on the frame through at least three ovens and heating the three thermoplastic sheets to a heat deformable temperature; moving the three heated sheets successively to a forming station on the frame; supporting in spaced apart overlying relation a first platen and a second platen on the forming station, and causing the platens to travel in opposed directions between open and closed positions; selectively positioning three molds on the first and second platens; selectively slidably moving a second one of the molds and a third one of the molds into and out of position on the second platen; moving the first and second platens in succession between the open and closed position to displace the three molds and to apply pressure to the three heated thermoplastic sheets in order to mold the sheets in a preselected configuration; moving one platen to compress a first one of the molded sheets against a second one of the molded sheets retained by the second platen in order to fuse together the two molded sheets to form a twin sheet molded article; and moving the platen retaining the twin sheet molded article into compression with the other platen retaining a third one of the molded sheets on the third mold in order to fuse together the twin sheet molded article and the third molded sheet to form a triple sheet molded article.
Claim 3
Dependent Claim 14 words
The method of claim 1 wherein the triple sheet molded article is a pallet.
Claim 4
Independent Claim 163 words
A method of making an article from at least first, second and third thermoplastic sheets on a machine having at least first, second and third molds, the method comprising: (a) heating the first thermoplastic sheet; (b) conforming the first sheet to the first mold; (c) heating the second thermoplastic sheet; (d) conforming the second sheet to the second mold; (e) aligning the first mold with the second mold so the first and second sheets face each other; (f) moving at least one of the first and second molds toward the other; (g) joining together sections of the first and second sheets to form a sheet subassembly; (h) heating the third thermoplastic sheet; (i) conforming the third sheet to the third mold; (j) aligning the third mold with the sheet subassembly; (k) moving at least one of the third mold and the sheet subassembly toward the other; and (l) joining together sections of the sheet subassembly and the third sheet thereby forming the article.
Claim 5
Independent Claim 163 words
A method of making an article from at least first, second and third thermoplastic sheets on a machine having at least first, second and third molds, the method comprising: (a) heating the first thermoplastic sheet; (b) conforming the first sheet to the first mold; (c) heating the second thermoplastic sheet; (d) conforming the second sheet to the second mold; (e) aligning the first mold with the second mold so the first and second sheets face each other; (f) moving at least one of the first and second molds toward the other; (g) joining together sections of the first and second sheets to form a sheet subassembly; (h) heating the third thermoplastic sheet; (i) conforming the third sheet to the third mold; (j) aligning the third mold with the sheet subassembly; (k) moving at least one of the third mold and the sheet subassembly toward the other; and (l) joining together sections of the sheet subassembly and the third sheet thereby forming the article.
Claim 6
Dependent Claim 16 words
The method of claim 3 wherein the sheets are joined together with the assistance of heat.
Claim 7
Dependent Claim 22 words
The method of claim 4 wherein the sheets are joined together only by heated fusing of desired portions of the thermoplastic sheets.
Claim 8
Dependent Claim 23 words
The method of claim 3 further comprising applying vacuum pressure to the previously heated sheets to conform the sheets in their respective molds.
Claim 9
Dependent Claim 41 words
The method of claim 3 further comprising nesting together previously formed legs projecting from each of the first, second and third sheets, with gaps being present between adjacent portions of the fully nested legs even after the sheets are joined together.
Claim 10
Dependent Claim 31 words
The method of claim 3 further comprising vertically moving both the first and second molds toward each other and subsequently vertically moving both the second and third molds toward each other.
Claim 11
Dependent Claim 24 words
The method of claim 3 wherein at least the first and third molds are alternately shuttled to a position aligned with the second mold.
Claim 12
Dependent Claim 26 words
The method of claim 3 further comprising creating a completely recyclable and entirely thermoplastic pallet having structural projecting legs and ribs between the joined adjacent sheets.
Claim 13
Dependent Claim 22 words
The method of claim 3 further comprising creating separated openings between joined inner margins in at least two of the joined sheets.
Claim 14
Dependent Claim 30 words
The method of claim 3 further comprising rotating a wheel retaining at least one of the molds, such that at least one of the sheets is moved between multiple ovens.
Claim 15
Independent Claim 156 words
A method of making a multisheet article with a first mold for a first sheet, a second mold for a second sheet, a third mold for a third sheet, and an abutment, the method comprising: (a) heating and forming the first sheet with the assistance of the first mold; (b) heating and forming the second sheet with the assistance of the second mold; (c) heating and forming the third sheet with the assistance of the third mold; (d) inserting the abutment into a gap between spaced apart peripheral margins of the first and second sheets; (e) joining together peripheral margins of the first and second sheets; (f) compressing together peripheral margins of the second and third sheets between the third mold and the abutment; (g) joining together the peripheral margins of the second and third sheets thereby forming the multisheet article; and (h) removing the abutment from between the first and third molds after step (g).
Claim 16
Independent Claim 156 words
A method of making a multisheet article with a first mold for a first sheet, a second mold for a second sheet, a third mold for a third sheet, and an abutment, the method comprising: (a) heating and forming the first sheet with the assistance of the first mold; (b) heating and forming the second sheet with the assistance of the second mold; (c) heating and forming the third sheet with the assistance of the third mold; (d) inserting the abutment into a gap between spaced apart peripheral margins of the first and second sheets; (e) joining together peripheral margins of the first and second sheets; (f) compressing together peripheral margins of the second and third sheets between the third mold and the abutment; (g) joining together the peripheral margins of the second and third sheets thereby forming the multisheet article; and (h) removing the abutment from between the first and third molds after step (g).
Claim 17
Dependent Claim 25 words
The method of claim 13 further comprising heating the peripheral margins of the second and third sheets through the third mold and through the abutment.
Claim 18
Dependent Claim 18 words
The method of claim 13 further comprising applying vacuum pressure to conform the sheets to their respective molds.
Claim 19
Dependent Claim 30 words
The method of claim 13 further comprising sensing the temperature during sheet joining by removably positioning at least one sensor adjacent to portions of the sheets to be fused together.
Claim 20
Dependent Claim 17 words
The method of claim 13 further comprising introducing compressed air between portions of the sheets during joining.
Claim 21
Dependent Claim 18 words
The method of claim 13 further comprising introducing compressed vaporized water between portions of the sheets during joining.

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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) 2004-09-24 2005-03-26 2005-09-25 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2008-09-24 2009-03-26 2009-09-25 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2012-09-24 2013-03-26 2013-09-25 $7700.00 Window Closed / Lapsed

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