Patent US2714382A successfully refreshed from Google Patents.
← Back to Patent Explorer
US4124434A Expired / Lapsed US ⏱️ 0.0 years remaining

Apparatus for lining by lamination air-permeable containers with thermoplastic sheeting or film

Assignee: Rissen Maschinenfabrik GmbH
•
Filing: 1976-10-26
•
Granted: 1978-11-07
•
Expires: 1996-10-26
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract Apparatus for lining by lamination air-permeable containers with thermoplastic film involving a deep drawing operation. The containers are held in deep drawing molds formed in a rotating table and the film blanks are formed from a film web onto individual holding means secured to another rotating table, the driving means for the tables being synchronized such that the film blanks are timely presented for the deep drawing operation following heating. Each holding means includes a metallic frame having a plurality of closely spaced pins for penetrating a film blank around the area to be deep drawn, the pins causing the area to be relieved of stresses during heating and shrinkage and hence troublesome wrinkles in the blanks prior to being deep drawn. Surprisingly, the pins do not cause tearing of even very thin film, because of the head conductor property of the pins and its effect on the arcing of the film blank in the vicinity of the pins as the blank shrinks.

Inventors

  • 👤 Fritz Wommelsdorf
  • 👤 Werner Schmidt

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 18:34
CPC Classifications
B; B29; B29C; B29C51/00; B29C51/26; B29C51/30; B29C51/32; B29C51/16; B29C51/165; B29C51/18; B29C51/20; B29C51/22; B29C51/42; B29C51/421; B29C51/424

Claims Analysis

Total Claims: 13
Claim 1
Independent Claim 158 words
In an apparatus for heating and deep drawing of thermoplastic film for lining air-permeable containers by lamination, said apparatus including a mold for supporting a container to be lined by deep drawing the film therein, means for holding the film, means for heating the held film, and means for deep drawing the film into the container, the improvement in said holding means for maintaining the film in a plane state, comprising a plurality of pins arranged in parallel to each other and perpendicular with the plane of said film, said pins piercing said film while holding the film, a first set of said plurality of pins being located at a distance opposite a second set of said plurality of pins, thereby bounding the area to be deep drawn, said pins being transverse to the shrinkage direction of the film, the distance between said first and second sets remaining constant while the film is being heated and deep drawn.
Claim 2
Dependent Claim 158 words
In an apparatus for heating and deep drawing of thermoplastic film for lining air-permeable containers by lamination, said apparatus including a mold for supporting a container to be lined by deep drawing the film therein, means for holding the film, means for heating the held film, and means for deep drawing the film into the container, the improvement in said holding means for maintaining the film in a plane state, comprising a plurality of pins arranged in parallel to each other and perpendicular with the plane of said film, said pins piercing said film while holding the film, a first set of said plurality of pins being located at a distance opposite a second set of said plurality of pins, thereby bounding the area to be deep drawn, said pins being transverse to the shrinkage direction of the film, the distance between said first and second sets remaining constant while the film is being heated and deep drawn.
Claim 3
Dependent Claim 26 words
Apparatus in accordance with claim 1, wherein said first and second sets of said plurality of pins completely surround the area subject to being deep drawn.
Claim 4
Dependent Claim 30 words
Apparatus in accordance with claim 2, wherein said pins in said first and second sets are spaced apart transversely to the main shrinkage direction not in excess of 15 mm.
Claim 5
Dependent Claim 24 words
Apparatus in accordance with claim 1, wherein said holding means includes a frame to which is secured at least said first set of pins.
Claim 6
Dependent Claim 27 words
Apparatus in accordance with claim 4, wherein said pins and said frame are metallic and said pins are secured in said frame so that heat conducts therebetween.
Claim 7
Dependent Claim 19 words
Apparatus in accordance with claim 4, and including heat conduction means for the removal of heat from said pins.
Claim 8
Dependent Claim 23 words
Apparatus in accordance with claim 4 wherein said frame is provided with cut-out sections between said pins to permit passage of stripping teeth.
Claim 9
Dependent Claim 32 words
Apparatus in accordance with claim 4, and including means for forming a film blank from a film sheet dimensioned for holding by said pins and transferring said film blank onto said pins.
Claim 10
Dependent Claim 139 words
Apparatus in accordance with claim 8, wherein said holding means includes a plurality of frames and wherein said film sheet is a continuous web and is conveyor mounted, and wherein said forming and transferring means includes a transfer wheel, a plurality of outwardly displaceble guides mounted circumferentially contiguously on said transfer wheel, along which in their retracted positions is placed the continuous film web, each of said guides having a retaining means at its extremity onto which said film blank is formed from the web and temporarily held during transfer of the blank, said plurality of frames being conveyed past said transfer wheel at a uniform distance therefrom to permit uniform outward movement of said guides to permit transfer of said film blanks from said retaining means of said guides to the pins of respective ones of said frames.
Claim 11
Dependent Claim 73 words
Apparatus in accordance with claim 4, wherein said holding means includes a plurality of frames mounted on a first revolving table and wherein said mold is formed in a second revolving table into which are formed additional similar molds, and including driving means for said first and second tables to cause them to cross each other to cause correspondence of said frames with a container supporting mold during the respective deep drawing operations.
Claim 12
Dependent Claim 17 words
Apparatus in accordance with claim 9, wherein the retracted positions of said outwardly displaceable guides are adjustable.
Claim 13
Dependent Claim 48 words
Apparatus in accordance with claim 1, and including an endless conveyor and wherein said holding means is arranged with other similar holding means on said conveyor so as to pass said holding means through a film introduction station, a film heating station and a film deep drawing station.

References Cited (Backward Citations)

US2736065A Cited
US2509439A Cited
US2559573A Cited
US2891280A Cited
US3134307A Cited
US3528865A Cited
US3697369A Cited
US3933562A Cited
US3957558A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1981-11-06 1982-05-08 1982-11-07 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1985-11-06 1986-05-08 1986-11-07 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1989-11-06 1990-05-08 1990-11-07 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag