Printer head

Abstract

A printer head having a circular first yoke, a cylindrical permanent magnet fixed on the circular first yoke, a (n) number of electromagnets (n is an integer) positioned on a circle on the first yoke within the permanent magnet having predetermined angle intervals, a ring shaped second yoke fixed on the permanent magnet so that the upper surface of the second yoke is on the same plane as that of the upper surface of the electromagnets, a ring shaped spacer positioned on the second yoke, a disk shaped spring fixed on the spacer having a common outer ring and a (n) number of projections projected in the internal direction from the common outer ring, (n) number of armatures each fixed on each projection of the spring, (n) number of print needles each fixed to each armature so that a print needle is perpendicular to the plane of the spring, a circular yoke plate fixed on the spring having (n) number of radial slits for accepting the armatures and the width of each slit being narrower than the width of projection of the spring, a guide frame fixed on the yoke plate having a ring and a hollow cylindrical post positioned at the center of the ring, the post having a guide slit at the top of the guide frame for accepting the tops of the aligned print needles, a side hole at the side of the post at the extension of the guide slit being provided. And an oil felt being provided on the inner wall of the permanent magnet.