GB182954A - Improvements in ribbon mechanism for typewriters - Google Patents

Abstract

182,954. Rogers, H. F., (Woodstock Typewriter Co.). April 19, 1921. Ink-ribbon mechanism.-Automatic feed-reversal mechanism comprises members which are reciprocated at each operation of the machine and co-operate with universally-mounted levers controlled by the ink-ribbon on the spools. In the mechanism shown in Figs. 2 and 3, each spool 74 is associated with the following mechanism. The spool shaft 75 is provided with a ratchet-wheel 76 co-operating with a feed-pawl 77 and a detent 85. the feed-pawl being connected to an arm 79 on a rock-shaft 80 which is connected to a universal bail 83 operated by the type-levers. The detent is secured to a yoke 86, pivoted on a stationary pin 87, and is provided with a headed pin 88 passing through a slot in the feed-pawl, a spring 99 being stretched betwen the voke and the feedpawl. The yoke engages a pin 91 on an arm 92,. secured to a sleeve 109 which can rock on a stationary vertical pivot 110. A feeler 100, Fig. 3, engaging the inner coil of the ink-ribbon, is pivoted on a sleeve 102 on the spool shaft, and engages the end 105 of a rod 104 which can slide in the spool shaft. The arm 92 is provided with a pin 93 engaging a grooved collar 94 on a rod 95 which can slide in the rock-shaft 80. A universally-mounted lever, consisting of a forked arm 107 mounted on horizontal pivots on the sleeve 109, engages a grooved collar 106 on the rod 104, and carries a roller 112 co-operating with a flange 113 on a reciprocating bar 114, which is connected to an arm 115 on the rock-shaft 80 and is reciprocated at each operation of the machine. The feelers normally retain the rods 104 and the arms 107 in the elevated position, the rollers 112 being out of the paths of the flanges 113. When, however, either spool is empty, the associated feeler permits the rod to drop, and the roller drops into the path of the flange. On the next operation of the machine, the arms 92, 107 are rocked bv the slide, and the pin 91 moves away from the yoke 86 and permits the spring 99 to move the feedpawl and detent into engagement with the ratchetwheel. Simultaneously, the rod 95 rocks the arm 92 associated with the full spool, and thereby causes the feed-pawl and detent of that spool to be released from the ratchet-wheel. The mechanism effects reversal positively and without strain on the ribbon. One of the arms 92 is formed with a V-end which passes over a roller on a spring-urged lever. The spool is provided with a grooved pin 118, Fig. 3, engaging a coupling- spring 117 on the sleeve 102. To prevent interference when a spool is placed on the spindle, the feeler is automatically raised when a spool is removed, bv means of a spring-urged lever 119 which is pivoted on the sleeve and is formed with a flange 121 engaging the feeler. An arm 122 of the lever normally abuts on the bottom spoolflange.