Actuator for Wire of Matrix Printer
Original Publication Date: 1978-Jan-01
Included in the Prior Art Database: 2005-Feb-20
A wire printer actuator comprises a bobbin 10 wound with an energizing coil comprising forward winding 11 and rear winding 12. A wire element 13, such as a wire for a matrix printer, extends into a central opening 14 in the bobbin 10. Attached to the actuator end of the wire element 13 are cylindrical front and rear permanent magnets 15 and 16, respectively, with polarities as shown. A cylindrical soft iron magnet 17 is attached to the wire element between the permanent magnets 15 and 16. The permeability of the magnet 17 is substantially greater than the permanent magnets so that its diameter may be reduced in its center region without appreciable reduction in magnetic flux. A soft iron plug 18 in the end of bobbin 10 in the region of rear winding 12 completes the magnetic circuit.