Labelling machine

#1. Field of the Invention

#The present invention relates to a labelling machine which sticks a label on the external surface of an object having a planar or a curved surface, such as a bottle, a can, a paper cylindrical container, a recording tape cassette, etc (hereinafter referred to as a container).

#2 Description of the Prior Art

#These and other objects and advantages of the invention will become more fully apparent as the following description is read in conjunction with the drawings wherein:

#FIG. 1 is an overall plan view of a labelling machine in accordance with the present invention;

#FIG. 2 is a plan view of the label suction drum illustrating its positioning relative to the label applicator drum;

#A label applicator drum 1 rotates in the center of a labelling machine. A plurality of label suction drums 2 are arranged around the label application drum 1. A label holder 3 is positioned adjacent to each label suction drum 2. The label holders 3 are permitted a horizontal swing motion. A paste application drum 5 is arranged between the last one of the label suction drums 2 and the container to apply paste to the labels. A conveyor 4 is positioned adjacent to the label applicator drum 1 for conveying containers to the label applicator drum 1. At the instant when a container makes contact with the label sticking drum 1, a label held by suction applied along the external surface of the label applicator drum 1 is urged against an external surface of the container. As a result, a label is transferred to the container and sticks on the external surface of the container. As will be explained later, the present invention is directed to the action by which a label is transferred from the label suction drum 2 to the label application drum 1.

#A number of air passages 7 are provided in the label applicator drum 1. The air passages form air suction holes 11, at one end, on the cylindrical surface of the label applicator drum 1. At their other end, the air passages 7 form a series of openings 8 arranged on the undersurface of the label applicator drum 1. An air suction groove 12 is arranged along the upper surface of a bed plate 14 on which the label sticker drum 1 is rotatably supported. The air suction groove 12 abuts the locus of the series of openings 8. A vacuum pump (not shown) is connected with the air suction groove 12. The air suction groove 12 extends from a position close to the first one of the label suction drums 2 to a position close to the conveyor 4, as shown by broken lines in FIGS. 1 and 2. Therefore, as the label applicator drum 1 rotates, vacuum is applied selectively to a limited number of the air suction holes 11 as they pass over and along the air suction groove 12.

#The label suction drums 2 rotate around respective vertical shafts. A plurality of label suction drums 2 are arranged around the label applicator drum 1 as shown in FIG. 1. The cylindrical external surface of the label suction drum 2 is split into upper and lower portions 2a, 2b, respectively, by a circular groove 21 formed at the center of the generation line thereof, as shown in FIGS. 3-8. Pairs of projections 22 are provided at uniform angular intervals on both the upper and lower halves 2a, 2b of the label suction drum 2. A non-projected cylindrical portion, or horizontal groove 25, separates each pair of projections 22 as shown in FIGS. 5-7.