Patent GB-374138-A (GB)
Title: Improvements in ink ribbon mechanism for typewriting machines
IPC: B41J33/514
Filed: 1931-03-05
Abstract: 374,138. Ink-ribbon mechanism. JAMES, R. W., 11, Queen Victoria Street, London..-(Remington Typewriter Co. ; Ilion, New York, U.S.A.) March 5, 1931, No. 6911. [Class 100 (iv).] Automatic reversal.-Operating-devices for the ribbon-feeding means are carried by a reversing-member which is automatically shifted by co-operation of one or other of the operating-devices with an associated interponent controlled by the ribbon. To prevent disablement of the ribbon-feed by stalling of the reversing-member in midposition, means is provided for automatically shifting the reversing-member on operation of the machine. In the mechanism shown in Figs. 1 and 6, each spool is provided with a ratchet wheel 31 co-operating with a feed-pawl 29 and a detent 32 on an operating- device or bell crank 23 connected by a link 20 to an arm 17 on a rock-shaft 13 carrying a universal bar 7 which is operated by the key - levers 5 and a returning - spring 56. 'The bell cranks are mounted on a reversing- member 26 consisting of a bar having pins 60, 61, 62 engaging apertures in the framework 1. Each spool is provided with an interponent 51 consisting of a rod connected to a lever which normally engages the inner coil of the ribbon and maintains the interponent out of the path of the associated bell crank. When the ribbon has been wound off either spool, the interponent drops and on operation of a key-lever the bell crank abuts on the interponent and shifts the reversing- member, the pawls and detents of the empty and full spools being thereby moved into and out of engagement with the ratchet wheels. The bell cranks have enlargements 27a for preventing the interponents from dropping at the wrong side of the bell cranks. The disengaged pawl and detent are prevented by a pin 36 from engaging their ratchet wheel. The movements of the reversing-member towards the right or left are completed by an over-centre C-spring 66 connected to pins 67, 68 on the framework and reversing-member. The pins 60, 61, 62 arc provided with sounddeadening washers. For automatically shifting the reversing-member if it is stalled in midposition, for instance by handling the pins when the machine is lifted, the rock-shaft 13 is provided with a bevelled arm 118, Fig. 6, which, on depression of the keys, co-operates with a bevelled projection 115 on the reversing- member. Specification 372,477 is referred to. Vibrator mechanism.-A vibrator 89, Fig. 1, is mounted on parallel links 94, 87 pivoted on a bracket 84 on the carriage 86, the link 87 having an extension connected to an actuating-lever 75 on the framework by a link 79 arranged to permit carriage shift. The actuating-lever has a slot 74 engaging a pin 73 on a link 72 which is connected to an arm 59 on the rock-shaft 13 and can be adjusted laterally by means of a finger-lever 105 to adjust or silence the vibrator. The fingerlever is connected by a link 100 to a bell crank 96 having a pin 97 engaging a slot in the link 72. The movements of the finger-lever are limited by slots, an over-centre C-spring 109 holding the finger-lever in either extreme position. To silence the vibrator, the finger-lever is set in mid-position, the pin 73 being thereby set opposite a recess 74a in the slot 74.