Electromagnetic wire printer

In a wire printer of the type comprising a group of substantially straight and substantially parallel printing wires, means for guiding the printing ends of said wires for longitudinal movement towards and away from a printing station, a group of electromagnets comprising one electromagnet for each of said printing wires, means for supporting said electromagnets in a row extending along said group of printing wires, each of said electromagnets comprising a core extending at right angles to the printing wires and having a front end adjacent to said group of printing wires and a rear end remote from said group of printing wires, a winding on said core, an armature extending along said core, means for pivotally connecting said armature to the rear end of said core, a biasing spring tending to move the armature away from the front end of the core, and means for connecting the front end of the armature to the rear end of a corresponding one of said printing wires for imparting said longitudinal movement thereto,

• the improvement characterized in
• that each of said cores consists of a substantially plane strip the plane of which forms right angles with the printing wires, and
• that each of said armatures consists of a strip having a flat main portion, a rear portion magnetically connected to the rear end of the core strip, and a front portion offset towards the core to form a pole face separated from the front end of the core by an air gap,
• and that the printer comprises at least two groups of printing wires and at least two corresponding rows of electromagnets, each of the core strips of one row being connected at its rear end to a core strip of the other row by a yoke-piece integral with the strips.

A wire printer comprising a group of substantially straight and substantially parallel printing wires, means for guiding the printing ends of said wires for longitudinal movement towards and away from a printing station, a group of electromagnets comprising one electromagnet for each of said printing wires, means for supporting said electromagnets in a row extending along said group of printing wires, each of said electromagnets comprising a core consisting of a substantially plane and substantially straight strip the plane of which and the longitudinal axis of which form right angles with the printing wires, said strip having a front end adjacent to said group of printing wires and a rear end remote from said group of printing wires, a winding on said core, an armature extending along said core, said armature consisting of a strip having a flat main portion, a rear portion magnetically connected to the rear end of the core strip, and a front portion offset towards the core to form a pole face separated from the front end of the core by an air gap, means for pivotally connecting said armature to the rear end of the core, means for connecting the front end of the armature to the rear end of a corresponding one of said printing wires for imparting said longitudinal movement thereto, a flat biasing spring tending to move the armature away from the front end of the core, said flat biasing spring being attached to the flat main portion of the armature strip at the side of said strip facing away from the core strip and having a front extremity extending beyond said flat main portion, each of said core strips being provided with a rest member for said front extremity of the flat biasing spring, said rest member being rigidly attached to the front end of the core strip and being arranged to engage the side of the spring engaging the armature strip, and a stop member for limiting the movement of the armature away from the core, said stop member being integral with said rest member.