Patent ID: 7690175
Filing Date: 2010-04-06
Classification: B65B

Abstract:
1. A method for the packaging of articles ( 1 / 7 ) with a film ( 16 ) made of plastic material, using a packaging machine ( 10 ) equipped with two transversal welding devices ( 18 ; 20 ) situated in succession along a longitudinal direction (F), comprising the following phases: positioning said articles ( 1 / 7 ) on a conveyor belt ( 12 ) with pushers which moves in a longitudinal direction (F) activated by a conveyor motor ( 14 ); distancing said articles ( 1 / 7 ) by means of a mechanism so that between each of said articles ( 1 / 7 ) there is a constant space or pitch; feedingthe film ( 16 ) destined for wrapping the articles ( 1 / 7 ) to be packaged, in the advance direction (F) of said conveyor belt( 12 ); longitudinally welding the film ( 16 ), in the advance direction (F) of the conveyor belt ( 12 ), so as to form a tubular casing which envelops said articles ( 1 / 7 ) aligned along said conveyor belt ( 12 ); activating a motor ( 38 ) and an oscillator ( 42 ) of the welding device ( 20 ) situated downstream with respect to the welding device ( 18 ) in a longitudinal direction (F) to weld and separate said film ( 16 ) in the portion of space between one article ( 2 ) and the subsequent article ( 3 ); and activating a motor ( 36 ) and an oscillator ( 40 ) of the welding device ( 18 ) situated upstream with respect to said welding device ( 20 ) in a longitudinal direction (F) to weld and separate said film ( 16 ) in the portion of space between said article ( 3 ) and the subsequent article ( 4 ) wherein the rotation rate of the motor ( 36 ; 38 ) and oscillator ( 40 ; 42 ) of each transversal welding device ( 18 ; 20 ) is increased with respect to the rotation rate of the conveyor motor ( 14 ) which moves said conveyor belt ( 12 ) forward so as to compensate for longitudinal movements of the film ( 16 ) with respect to the conveyor belt ( 12 ).