Abstract: A compact, light weight, high speed, dot matrix printing head comprises a generally circular array of stylus drivers. The printing head employs a generally circular permanent magnet common to all drivers and mounted centrally of the device. Each driver includes an arm having a stylus secured at one end thereof generally perpendicular to the arm and an armature of an electromagnet mounted on the other end of the arm. A magnetic circuit of each driver includes a section of the permanent magnet and bucking coil electromagnet in a short generally rectangular structure with the armature located at one corner of the structure such corner formed by a pole of electromagnet and a pole of the permanent magnet. The arm is carried on crossed flexures providing a pivot point for the arm in the plane of the interface of the armature and pole of the electromagnet to reduce wear. The arrangement of the structure causes the air gap forces to produce moments which are additive.

Abstract: An arm for holding the impact stylus of a high speed dot matrix printer is fabricated from a single stamping which when properly folded defines two members having C-shaped cross-sections joined by a thin web. The web is folded around the stylus to bring the 4 legs of the two C-shaped members into overlapping relationship to define a hollow elongated and tapered arm having the stylus substantially wholey encircled by the web whereby after brazing the stylus is securely held.

Abstract: An arm for holding the impact stylus of a high speed dot matrix printer is fabricated from a single stamping which when properly folded defines two members having C-shaped cross-sections joined by a thin web. The web is folded around the stylus to bring the 4 legs of the two C-shaped members into overlapping relationship to define a hollow elongated and tapered arm having the stylus substantially wholly encircled by the web whereby after brazing the stylus is securely held.

Abstract: An arm for holding the impact stylus of a high speed dot matrix printer is fabricated from a single stamping which when properly folded defines two members having C-shaped cross-sections joined by a thin web. The web is folded around the stylus to bring the 4 legs of the two C-shaped members into overlapping relationship to define a hollow elongated and tapered arm having the stylus substantially wholey encircled by the web whereby after brazing the stylus is securely held.

Abstract: A high speed printing head comprises a circular array of stylii drivers for printing characters in a dot matrix format. Each driver includes a permanent magnet and bucking coil electromagnet which when energized causes a stylus to impact a printing surface. The stylus is carried on the end of an arm supported by crossed horizontal and vertical supporting flexures at its other end whereby the arm pivots about a virtual axis lying near the plane of the working air gap of the electromagnet to reduce wear of the pole piece and armature and increase impact rebound of the arm. The magnetic structure and arm structure intersect only above the pole piece reducing flux leakage and size and weight of the structure. The arm and flexure structures are non-magnetic except at said region of intersection to reduce, in conjunction with the single region of intersection of said structures, cross-talk between adjacent drivers.

Abstract: A printing head provides an array of stylii and stylii drivers for forming characters in accordance with a desired matrix of dots. Each driver comprises a flat piezoelectric ceramic wafer and a levered beam having a stylus secured to one end and providing at the stylus end a multiplication of the movement of the wafer of approximately 4 to 1 to 7 to 1. The wafers and supporting structure are circular and structured to nest preferably coaxially, with each levered beam lying at a small angle relative to its adjacent beams so that the printing ends of the stylii may be constrained to lie along a straight line perpendicular to the direction of movement of the head.