Needle printing head

Printing head with needles comprising a support (11) able to axially guide a plurality of printing needles (15), each of which has one end attached to a mobile armature (16) of a corresponding actuation electromagnet (17) having a ferromagnetic core (18) provided with polar expansions, a separation element (30) being interposed between the mobile armatures (16) and the corresponding polar expansions, the printing head being characterized in that said separation element (30) is made of a metal material and comprises means (33, 34) able to reduce the effect of eddy currents which are generated by energizing of every electromagnet (17), the separation element (30) comprising a plurality of apertures (32) each one associated with the polar expansions of an electromagnet (17) and said means to reduce the eddy currents comprising notches (33) associated with each of said apertures (32), wherein the electromagnets (17) of said printing needles (15) are arranged spoke-like, said printing head being further characterized in that said separation element (30) further comprises a central hole (31), that said apertures (32) are positioned radially with respect to said central hole (31) and that a first group of said notches (33) is arranged radially between said apertures (32) and said central hole (31).