Abstract: A mounting arrangement for mounting a printer component to a support, using a foil including a number of mounting apertures, into which pins are inserted to provide alignment. The engagement of the pins in the aperture causes local deformation of the foil, the resulting forces acting to align the pins to an accuracy which can be greater than that to which the foil is manufactured.

Abstract: The thermal printer of the invention comprises a frame, a print head tiltably mounted in the frame, and a spring carried by the frame and forming a member for urging the print head into its printing position, with a flexible sheet of conductors terminating at the print head. According to the first characteristic of the invention, the spring is made of an electrically conductive material and includes a finger for being received in a corresponding orifice of the frame, while a portion of the sheet carries a conductive eyelet through which the finger of the spring passes when the spring is received in the orifice of the frame, the spring thus pinching the eyelet against the frame.

Abstract: A wire dot printer head of the present invention is provided with an abrasion preventive member in a yoke. The abrasion preventive member encloses the outer periphery of the armature support shafts. The yoke, together with an armature spacer having a plurality of cutouts for holding the armature support shafts, holds the armature support shafts. The armature support shafts do not directly contact the yoke because of the use of the abrasion preventive member. It is therefore possible to restrain abrasion of the yoke surface and accordingly to prevent deterioration in printing quality.

Abstract: An ink density closed loop control system for an ink ribbon of an impact printer having a reservoir roller formed of an ink absorbent material with at least one or more channels within the reservoir roller fluidly connected to a pump and ink supply. A transfer roller can contact the reservoir roller for imparting ink to the ink ribbon. A sensor senses the relative amount of ink on the print ribbon and an electrical drive responsive to the sensor drives the pump for a flow of ink to the one or more channels. The sensor can sense ink on different segments of the ribbon and, with two or more channels in the reservoir roller can distribute ink to two or more segments of the reservoir roller depending upon the ink sensed at a particular segment of the ribbon. A further enhancement of this invention provides a multi-viscosity ink to compensate for changes in ambient temperature conditions.

Abstract: A wire dot printer head including a yoke, cores arranged in an annular form on the yoke, coils combined with the cores so as to fit the cores, armatures supported so as to be raised or lowered in respect to the cores, wires supported at the free ends of the armatures in such a way that they may be driven and displaced, and an extremity end guide having guide holes for independently and slidably supporting the extremity ends of the wires to arrange them. When the moving direction of the wire dot printer head is as a main scanning direction, the guide holes of the extremity end guide are arranged along an arc curved only in direction of the sub-scanning direction so as to cause the arrangement positions in the main scanning direction to be made different.