Package making – Methods – Wrapping contents including cover forming
Reexamination Certificate
1999-07-06
2001-07-24
Lazarus, Ira S. (Department: 3721)
Package making
Methods
Wrapping contents including cover forming
C053S466000, C053S234000
Reexamination Certificate
active
06263644
ABSTRACT:
The present invention relates to a method of wrapping a product in a sheet of heat-seal wrapping material.
The present invention may be used to particular advantage on machines for cellophaning packets of cigarettes, to which the following description refers purely by way of example.
BACKGROUND OF THE INVENTION
On known machines for cellophaning packets of cigarettes, a sheet of heat-seal wrapping material is folded against one wall of the product, and at least two portions of the sheet of wrapping material superimposed one on top of the other; and a sealing surface of a sealing head is then brought into and maintained for a given length of time in contact with the superimposed portions to seal the portions together and stabilize the sheet of wrapping material in the folded configuration.
On known cellophaning machines, the sealing surface of the sealing head is maintained constantly at an operating temperature which gets closer to the melting temperature of the heat-seal material in direct proportion to the increase in the operating speed of the machine.
When the sealing surface is brought rapidly into contact with the superimposed portions of the sheet of wrapping material and the temperature of the sealing surface is close to the melting temperature of the heat-seal material, the portions of the sheet of wrapping material contacting or close to the sealing surface tend to crease and/or become undulated, thus seriously impairing the appearance of the wrapping. This problem is particularly noticeable on modern cellophaning machines operating at very high speeds of over 500 packets a minute.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a method of wrapping a product in a sheet of heat-seal wrapping material, designed to eliminate the aforementioned drawback, and which at the same time is both straightforward and cheap to implement.
According to the present invention, there is provided a method of wrapping a product in a sheet of heat-seal wrapping material, the method comprising the steps of folding said sheet of wrapping material about said product and superimposing at least two portions of the sheet of wrapping material one on top of the other against a wall of said product; establishing contact between the superimposed portions and a sealing surface of a sealing head; maintaining the sealing surface in contact with said superimposed portions for a given time interval; and cutting off contact between the sealing surface and said superimposed portions; characterized in that the temperature of the sealing surface is set to a lead-in first value as the sealing surface first contacts said superimposed portions, and is increased to a working second value during said given time interval.
The present invention also relates to a machine for wrapping a product in a sheet of heat-seal wrapping material.
According to the present invention, there is provided a machine for wrapping a product in a sheet of heat-seal wrapping material, the machine comprising folding means for folding said sheet of wrapping material about said product and superimposing at least two portions of the sheet of wrapping material one on top of the other against a wall of said product; a sealing head having a sealing surface; actuating means for establishing contact between the superimposed portions and the sealing surface of said sealing head; and control means for controlling the temperature of said sealing surface; characterized in that said control means provide for setting the temperature of the sealing surface to a lead-in first value upon the sealing surface first contacting said superimposed portions, and for increasing the temperature of the sealing surface to a working second value during a time interval in which the sealing surface contacts said superimposed portions.
REFERENCES:
patent: 3035379 (1962-05-01), Cloots et al.
patent: 3348474 (1967-10-01), Virta et al.
patent: 3431398 (1969-03-01), Wahle et al.
patent: 3864186 (1975-02-01), Balla
patent: 5123226 (1992-06-01), Near
patent: 5477661 (1995-12-01), Draghetti et al.
patent: 5613344 (1997-03-01), Osti et al.
patent: 5811185 (1998-09-01), Schreck et al.
patent: 5900310 (1999-05-01), Murschall et al.
patent: 5996318 (1999-12-01), Draghetti
patent: 6000199 (1999-12-01), Boldrini
patent: 8839253 (1998-11-01), Draghetti
patent: 3718702 (1988-12-01), None
patent: 0079760 (1983-05-01), None
patent: 2277729 (1976-02-01), None
patent: 2045678 (1980-11-01), None
English Translation of Abstract of DE 3718702.
English Translation of Abstract of FR 2277729.
Ghini Marco
Spatafora Mario
G. D Societa' per Azioni
Huynh Louis K.
Ladas and Parry
Lazarus Ira S.
LandOfFree
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