Apparatus and method for heating a movable web

Patent metadata

Field	Value
Publication number	US-2023090054-A1
Application number	US-202217947424-A
Country	US
Kind code	A1
Filing date	Sep 19, 2022
Priority date	Sep 20, 2021
Publication date	Mar 23, 2023
Grant date	—

Abstract

A heating unit for heating a continuous web, includes a heating roller rotating about an axis of rotation and having an outer surface comprising a pattern of thermally conductive areas and thermally insulating areas, and at least one induction heater electromagnetically coupled to the thermally conductive areas of the outer surface of the heating roller.

First claim

1 . A heating unit for heating a continuous web, comprising:
a heating roller rotating about an axis of rotation and having an outer surface comprising a pattern of thermally conductive areas and thermally insulating areas, and a heating device for heating said thermally conductive areas, comprising at least one induction heater electromagnetically coupled to said thermally conductive areas of the outer surface of the heating roller.

2 . The heating unit of claim 1 , wherein said at least one induction heater is stationary.

3 . The heating unit of claim 1 , wherein said at least one induction heater has an electromagnetic emitting window facing said outer surface of the heating roller.

4 . The heating unit of claim 3 , wherein said at least one induction heater is movable with respect to the heating roller between a close-up operative position and a spaced apart inoperative position, so that in said inoperative position a continuous web can be inserted between said emitting window and said outer surface of the heating roller.

5 . The heating unit of claim 1 , wherein the pattern of thermally conductive areas comprises a plurality of frame-shaped thermally conductive areas surrounding corresponding thermally insulating areas.

6 . The heating unit of claim 1 , wherein said thermally conductive areas are formed by two continuous longitudinal thermally conductive elements and by a plurality of transverse heating elements extending between the two continuous longitudinal thermally conductive elements.

7 . The heating unit of claim 1 , further comprising a temperature sensor configured for detecting a temperature of the continuous web downstream of said at least one induction heater and a power unit configured for adjusting an intensity of an electromagnetic field generated by said at least one induction heater depending on the temperature detected by said temperature sensor.

8 . An apparatus for packaging articles, comprising:
first and second feeding assemblies configured for feeding first and second continuous webs in respective longitudinal directions, an inlet conveyor configured for feeding a flow of articles between said first and second continuous webs, an overlapping unit configured for overlapping to each other the first and second continuous webs on opposite sides of said flow of articles, a compression unit configured for compressing said first and second continuous webs around articles of said flow of articles, and at least one heating unit for heating at least one of said first and second continuous webs, the at least one heating unit comprising:
a heating roller rotating about an axis of rotation and having an outer surface comprising a pattern of thermally conductive areas and thermally insulating areas, and
a heating device for heating said thermally conductive areas, comprising at least one induction heater electromagnetically coupled to said thermally conductive areas of the outer surface of the heating roller.

9 . A method for heating a continuous web, further comprising:
providing a heating roller configured to rotate about an axis of rotation and having an outer surface comprising a pattern of thermally conductive areas and thermally insulating areas, feeding a movable continuous web in contact with the outer surface of the heating roller, and generating an electromagnetic field inductively coupled to said thermally conductive areas so as to heat said thermally conductive areas by induction heating.

10 . The method of claim 9 , wherein said electromagnetic field is generated by at least one stationary induction heater.

11 . The method of claim 9 , wherein said electromagnetic field is emitted through an electromagnetic emitting window facing said outer surface of the heating roller.

12 . The method of claim 11 , wherein said movable continuous web moves through a gap defined between said electromagnetic emitting window and said outer surface of the heating roller.

13 . The method of claim 9 , further comprising:
feeding in respective longitudinal directions first and second continuous webs, at least one of which has a thermally activated adhesive on one surface thereof, feeding a flow of articles between said first and second continuous webs, overlapping said first and second continuous webs on opposite sides of said flow of articles, and compressing said first and second continuous webs around articles of said flow of articles and fixing to each other said first and second continuous webs by said thermally activated adhesive, wherein before overlapping said first and second continuous webs on opposite sides of said flow of articles, at least one of said first and second continuous webs is passed on the outer surface of the heating roller heated by induction heating.

14 . The method of claim 13 , wherein said at least one of said first and second continuous webs is locally heated along frame-shaped heating areas.

15 . The method of claim 14 , wherein said first and second continuous webs are compressed along frame-shaped compression areas surrounding respective articles of said flow of articles and overlapped to respective heating areas.

Assignees

• Fameccanica Data Spa

Inventors

• Radovani Asti

Classifications

• B65B51/28

  Rollers for producing longitudinal and transverse seams simultaneously · CPC title

• B65B9/02 Primary

  Enclosing successive articles, or quantities of material between opposed webs · CPC title

• B29C65/32 Primary

  Induction · CPC title

• B29C66/433

  Casing-in, i.e. enclosing an element between two sheets by an outlined seam (for bookbinding B42C11/06; for packaging B65B; by laminating B32B37/00; enclosing tubular articles between substantially flat elements B29C66/53261) · CPC title

• B65B11/12

  and then to form closing folds of similar form at opposite ends of the tube · CPC title