Device for cutting labels in a labelling machine

Device (1) for cutting labels in a labelling machine, comprising:

• a cutting roller (2) having at least one blade (3) co-operating with a fixed counter-blade (4) able to be operatively associated to the roller for cutting the labels;
• a mechanical shaft (5) whereon is keyed said cutting roller (2);
• a frame (6) to support said mechanical shaft (5);
• a heat exchanger circuit containing an operating fluid, a first portion (9a) of said circuit being constructed on said support frame (6), said exchanger circuit thermally interacting with said frame (6);
• means for generating a flow of said operating fluid within the heat exchanger circuit, characterized in that said means for generating a flow of said operating fluid are connected to the mechanical shaft (5) and are operatively inserted in said heat exchanger circuit;
• said means for generating a flow of said operating fluid comprising an impeller (10) connected to the mechanical shaft (5), the heat exchanger circuit being a closed circuit through a plurality of passageways so that the operating fluid, during operation, is recirculated through said closed circuit, wherein the closed circuit passageways pass through a first bearing, then longitudinally through the mechanical shaft, then through a second bearing, then back through said frame to said first bearing again, to thereby regulate the temperature of the cutting roller, bearings and frame.