Patent GB-1431745-A (GB)
Title: Printing apparatus
IPC: B41J3/38
Filed: 1974-01-30
Abstract: 1431745 Selective printing KROY INDUSTRIES Inc 30 Jan 1974 [30 Jan 1973] 04248/74 Heading B6F A tape printer comprises a type disc 36, Fig. 14, a print hammer in the form of a piston 155, tape feed means 70, Fig. 3, and ink ribbon feed means, 111, the impact of the piston 155 being variable in accordance with the area of the character printed, the type disc having positive alignment pins 31, and the type being fed a variable distance dependent on the character printed. After setting the type disc 36 manually, a print button 28 is depressed, whereupon a motor 10 is energized if the type disc is correctly aligned, and is connected to a cam assembly 14 for a single revolution thereof. During such revolution an arm 65 is pivoted through cam surface 42, the arm 65 idling about a shaft 68 to which the tape feed roller 70 is fixed, and an arm 106 idles about a shaft to which the ink ribbon feed roller 111 is fixed. The hammer piston 155 is also drawn downwardly against a driving spring 156, Fig. 14. As the cam continues to rotate, the hammer piston 155 is released causing an impression, the ink ribbon feed roller is rotated by the arm 106 returning and being clutched to the ink ribbon feed roller shaft, and the tape feed roller is-driven by the return of the arm 65 now clutched to shaft 68. Impact adjustment.-The type disc, Fig. 12, is provided with a ring 177 of varying radius which is sensed by a pin 175, Fig. 3, and whereby the position of a spring clip 162, Fig. 14, is adjusted according to the character being printed. The compression of the spring 156 is thereby adjusted to vary the impact pressure. Character and word spacing adjustment.-The type disc is also provided with a ring 76 which is sensed by a projection 75, Fig. 3, on the arm 65 during the feed rotation of the tape feed roller 70. The extent of tape feed is thereby adjusted according to the character selected. Spacing between words is achieved by depressing a button 82, whereby the shaft 68 is rotated through an arm 78. The extent of rotation of the shaft 68 and hence of the tape feed roller 70 is determined by the position of a stop 79 which can be adjusted by a manually rotatable wheel 63 according to the font being used. Ink ribbon feed adjustment.-The rate of feed of the ink ribbon is dependent on the position of the stop 79 which carries a sloping arm 118 sensed during the ink ribbon feed by a pin 116 on an arm 100 coupled to the arm 106. Alignment for impression.-On first depressing the print button 28, pins 31 are urged towards the type disc and enter notches 35, Fig. 14, therein to ensure accurate alignment of the type disc, A switch (40, Fig. 11, not shown) in the motor circuit is closed only when the pins 31 are in their correct position, thus preventing a print operation when the type disc is incorrectly aligned.  Back-spacing.-Two characters, e.g. A, W, can be closed together in kerned relationship by backspacing the tape before printing the second character, by depression of a button 142, Fig. 3. The button acts on mechanism 130 which grips the tape and draws it backwards to a limited extent. This is the subject of Specification 1,419,044.