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US4567713A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of and apparatus for producing a package

Assignee: Multivac Sepp Haggenmueller GmbH and Co KG
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Filing: 1984-05-14
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Granted: 1986-02-04
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Expires: 2004-05-14
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Abstract

Abstract A method of producing a package is provided wherein a product is brought into a depression formed using a shrinkable sheet material, a cover is brought over the depression, the sheet material is shrunk by heating and the depression is closed with a cover by heat-sealing. In order to shrink the depression free from creases onto different and irregular product surfaces steam is admitted to the sheet material having a saturation temperature above the sheet material temperature such that the steam condensing at the sheet material transfers its heat of condensation to the sheet material. The apparatus for performing the method comprises a sealing station with an upper tool and a lower tool movable relatively thereto and having a chamber for receiving the depression, the chamber being connected with a steam generator.

Inventors

  • 👤 Johann Natterer

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 04:59
CPC Classifications
B; B65; B65B; B65B53/00; B65B53/02; B65B53/06; B65B31/00; B65B31/02; B65B31/021

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 130 words
The method of packaging, comprising forming a depression in a heat-shrinkable sheet material by deep drawing such as to define a receptacle with a rim peripherally thereof, depositing the article to be packaged into the receptacle, providing a cover sheet of an area coextensive with the rim of the receptacle, placing the assembly comprising the receptacle and cover sheet in a closed chamber, evacuating the closed chamber, delivering heated steam into the evacuated chamber, measuring the pressure within the closed chamber, terminating delivery of steam into the closed chamber when the pressure in the closed chamber reaches a value corresponding to the saturation temperature of the steam which is substantially equal to the shrinkage temperature of the sheet material and heat-sealing the cover sheet to the rim of the receptacle.
Claim 2
Independent Claim 130 words
The method of packaging, comprising forming a depression in a heat-shrinkable sheet material by deep drawing such as to define a receptacle with a rim peripherally thereof, depositing the article to be packaged into the receptacle, providing a cover sheet of an area coextensive with the rim of the receptacle, placing the assembly comprising the receptacle and cover sheet in a closed chamber, evacuating the closed chamber, delivering heated steam into the evacuated chamber, measuring the pressure within the closed chamber, terminating delivery of steam into the closed chamber when the pressure in the closed chamber reaches a value corresponding to the saturation temperature of the steam which is substantially equal to the shrinkage temperature of the sheet material and heat-sealing the cover sheet to the rim of the receptacle.
Claim 3
Dependent Claim 10 words
The method of claim 1 wherein the steam is superheated.
Claim 4
Dependent Claim 23 words
The method of claim 1 wherein the walls of the chamber are heated to a temperature above the saturation temperature of the steam.
Claim 5
Dependent Claim 42 words
The method of claim 1, wherein the space surrounding the article to be packaged within the receptacle is evacuated during the heating of the sheet to an evacuation pressure being below the pressure in the chamber surrounding the outside of the depression.
Claim 6
Dependent Claim 177 words
Apparatus for producing a package by forming a depression in a heat-shrinkable sheet material such as to define a receptacle with a peripheral rim, inserting the article to be packaged into the receptacle and covering and heat-sealing a cover sheet to the rim of the receptacle; the apparatus comprising a sealing station having an upper tool part embodying a heating element and a lower tool part movable relative thereto, said lower tool comprising a chamber for receiving said receptacle, a steam generator connected with said chamber via a steam duct, means for measuring the pressure within said chamber and means for controlling the supply of steam to said chamber, said controlling means being controlled by said measuring means to start the supply of steam to said chamber at a first predetermined pressure within said chamber and to stop the supply of steam to said chamber at a second predetermined pressure within said chamber, said second predetermined pressure corresponding to a saturation temperature of said steam which is substantially equal to the shrinkage temperature of said sheet material.
Claim 7
Dependent Claim 177 words
Apparatus for producing a package by forming a depression in a heat-shrinkable sheet material such as to define a receptacle with a peripheral rim, inserting the article to be packaged into the receptacle and covering and heat-sealing a cover sheet to the rim of the receptacle; the apparatus comprising a sealing station having an upper tool part embodying a heating element and a lower tool part movable relative thereto, said lower tool comprising a chamber for receiving said receptacle, a steam generator connected with said chamber via a steam duct, means for measuring the pressure within said chamber and means for controlling the supply of steam to said chamber, said controlling means being controlled by said measuring means to start the supply of steam to said chamber at a first predetermined pressure within said chamber and to stop the supply of steam to said chamber at a second predetermined pressure within said chamber, said second predetermined pressure corresponding to a saturation temperature of said steam which is substantially equal to the shrinkage temperature of said sheet material.
Claim 8
Dependent Claim 46 words
The apparatus of claim 5, wherein said upper tool part comprises an upper chamber and said upper chamber and said chamber are adapted to be selectively connected with the suction side of a vacuum pump or with the ambient air by means of a connecting conduit.
Claim 9
Dependent Claim 67 words
The apparatus of claim 5, wherein said steam generator comprises a heated housing with a cylindrical interior space, a cylindrical body being inserted into said cylindrical space, said cylindrical body having an outer diameter corresponding to the inner diameter of said interior space and comprising a flute disposed on the cylindrical surface thereof and extending from one end plane to the other end plane of said body.
Claim 10
Dependent Claim 17 words
The apparatus of claim 7, wherein a heating element is provided in the walls surrounding said chamber.
Claim 11
Dependent Claim 24 words
The apparatus of claim 5, wherein a steam conduit comprising a steam valve is provided between said steam generator and said lower tool part.

References Cited (Backward Citations)

US3321886A Cited
US3956867A Cited
US4137688A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1989-02-03 1989-08-05 1990-02-04 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1993-02-03 1993-08-05 1994-02-04 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1997-02-03 1997-08-05 1998-02-04 $7700.00 Window Closed / Lapsed

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