Striker device for printers

In a striker device for printers, comprising a printing support;

• a character-carrying member of having individually movable characters;
• a print hammer which is actuatable in an impact sense and direction to cause a selected character of said character-carrying member to strike against said printing support;
• and an actuating member movable to actuate said hammer, wherein the improvement comprises silencer means comprising:
• guide means capable of ensuring freedom of movement for said actuating member with respect to said print hammer in said impact sense and direction;
• an element of elastomeric material interposed between said actuating member and said print hammer such as to transmit kinetic energy from said actuating member to said hammer with a delay, in which said element of elastomeric material is interposed between two oppositely-disposed surfaces of said print hammer and said actuating member respectively, which surfaces are transverse with respect to said impact direction, for applying a compression force to said element of elastomeric material;
• and
• a second element of elastomeric material which is interposed between two other oppositely-disposed surfaces of said actuating member and said print hammer respectively, and which can be subjected to a compression effect in response to a reciprocal movement of said actuating member with respect to said print hammer in said impact direction and opposite thereto.

A striker device for printers of the type comprising a platen roller;

• a character-carrying disc having characters carried by blades which are movable individually in an impact direction and sense;
• a print hammer which can be actuated to cause a selected character of said character-carrying disc to strike against said platen roller;
• an actuating unit for the print hammer which is provided with a stator body adapted for electromagnetic excitation and ferromagnetic armature capable of movement together with the hammer and in response to excitation of the stator body to actuate said hammer;
• and a return spring for returning the hammer towards a rest position, said print hammer and said ferromagnetic armature having a hammer mass and an armature mass respectively, wherein the improvement comprises silencer means comprising:
• guide means for causing said armature to be freely movable with respect to said print hammer in said impact sense and direction;
• and
• an element of elastomeric material interposed between said armature and said print hammer such as to transmit kinetic energy from said armature to said hammer with delay upon the striking of the selected character with a reciprocal movement of said actuating member with respect to said print hammer in said impact sense and direction, through said guide means;
• wherein the hammer mass and the armature mass are in an inertial ratio included between 0.25 and 1;
• and
• wherein the element of elastomeric material and the platen roller have levels of rigidities which are in a rigidity ratio included between 0.25 and 1 to prolong the action of the printing action of said hammer.