Patent ID: 8240805

Claim:
An assembly of a multiplicity of machines employed to perform a printing operation, where the said assembly has a single light source, with each machine including: a printing device that creates at least one inked zone ( 5 ) on a printing substrate, by means of at least one printing ink, a feedback loop ( 6 ) to perform the regulation of at least one characteristic of said inked zone ( 5 ), the feedback loop acting directly on the printing device; wherein the feedback loop includes: at least one control unit, to control at least one characteristic of the said printing ink, in accordance with a difference between at least one characteristic of a control inked zone ( 5 ) and at least one characteristic of a measured inked zone ( 5 ); at least one detection system ( 7 ) to measure at least one characteristic of said inked zone ( 5 ), where the detection system ( 7 ) includes: at least one sensor designed to capture light radiation reflected by the said inked zone ( 5 ), and to generate a signal representing at least the characteristic of the inked zone ( 5 ), and at least one first optical fibre ( 10 ), designed to convey, to the vicinity of the inked zone ( 5 ), light radiation emitted by the said single light source.