Labeling machine for heat shrink labels

A continuous method of applying heat shrinkable film to containers which comprises:

• (a) providing a continuous supply of such film
• (b) continuously severing the film into segments of the desired length
• (c) continuously transporting the severed segments to a film applicator station
• (d) continuously applying the segments of film at the applicator station to containers each of which has a main body portion having an upper end and a lower end and presenting a surface which is vertically linear and having also at least one end portion adjoining the body portion and curving inwardly therefrom, and causing at such applicator station the leading end of each segment of film to be applied to the main body portion of a container without heat shrinking it by spinning the container about its cylinder-axis, adhering the trailing end to the leading end by means of an adhesive thereby forming a side seam and also forming on each container at least one overlapping portion overlapping an end portion of the container but unattached thereto
• (e) providing an extensible-retractable tongue, extensible to and retractable from a heat shielding position wherein it acts as a heat shield between an exterior source of heat and said side seam,
• (f) cyclicly operating such extensible-retractable tongue to extend it to the heat shielding position and thereafter retracting it, and
• (g) applying heat from an external source to predominantly said end portion to shrink it onto the container while said tongue is in extended position.

Apparatus for continuously applying heat shrink film to containers having a cylindrical body portion and at least one end portion curving inwardly from the body portion said apparatus comprising:

• (a) a film feed for continuous supply of film material from a roll thereof
• (b) a continuous cutting assembly acting to sever segments of film from such supply
• (c) a continuously rotating vacuum drum serving to grip the leading end of each severed segment of film, to adhere to an applicator station and to release the segment at such station
• (d) a continuous container transport serving to transport containers continuously to said applicator station and then to a heating station
• (e) means for wrapping each segment of film about and adhering it to the body portion of each container without heat shrinking the same and forming a side seam in the form of an overlapping, adhesively secured bond between the leading and trailing ends of the segment and also forming an overlap of the segment opposite and unattached to at least one such end portion
• (f) heating means external to the film acting to apply heat to predominantly the overlap or overlaps to heat shrink them onto the container and
• (g) an extensible-retractable tongue extensible to and retractable from a heat shielding position wherein it acts as a heat shield between an external source of heat and said side seam,
• (h) means cyclicaly operating such extensible-retractable tongue to extend it to the heat shielding position and thereafter retracting it, and (i) means for operating said heating means to apply heat to predominantly such overlap during the period that said tongue is in extended position.

Apparatus for wrapping segments of heat shrinkable sheet material around articles, such articles having a cylindrical body and at least one end portion adjoining the body and sloping inwardly therefrom, said segments having a length greater than the circumference of the body to allow the segment to be wrapped around the body with an overlap sufficient to form a seam, said segments having a width greater than the length of the body such that, when the segment is wrapped around the body, an edge portion of the segment will overlap at least one sloping end portion and will stand free, said apparatus comprising:

• (a) an article transport adapted to transport such articles in sequence to an applicator station with the body of each article accessible
• (b) a segment transport adapted to transport such segments in sequence to said applicator station with the leading end of each segment tangent to the body of the respective container
• (c) means for adhesively securing such leading end to the body of the respective container by compressing the leading end between the container and the segment transport
• (d) means for then spinning the article about its cylindrical axis
• (e) means serving during such spinning to wrap the segment about the body,
• (f) means tangent to the body of the article serving to apply pressure to the overlapping ends of the segment to adhesively secure the trailing end to the leading end of the segment,
• (g) an extensible-retractable tongue extensible to and retractable from a position wherein it acts as a heat shield between an exterior source of heat and said seam
• (h) means cyclically operating such extensible-retractable heat shield means to extend it to heat shielding position and thereafter retracting it, and
• (i) means for applying heat from an external source to predominantly such edge portion or portions during the period that said heat shield means is in extended position.