Patent GB-374296-A (GB)
Title: Improvements relating to letter-spacing mechanism for typewriting machines
IPC: B41J19/42
Filed: 1931-06-30
Abstract: 374,296. Typewriters. FAIRWEATHER, W. C., 65, Chancery Lane, London.-(Underwood Elliott Fisher Co.; 342, Madison Avenue, New York, U.S.A.) June 30, 1931, No. 18813. [Class 100 (iv).] Letter-spacing mechanism. - Universal-bar mechanism is mounted as a unit on a detachable bracket, and escapement mechanism may be mounted as a unit on another bracket detachably secured to standards on the universal-bar bracket. The universal-bar mechanism shown in Figs. 2 and 5 and comprising a bail 30 attached to a table 31 is carried as unit by a bracket 48 which is secured to members 25, 28 of the framework and is inserted at the back of the machine. Standards 49, 50 on the bracket have extensions 51 supporting a rock-shaft 37 formed with arms 35, 36 which are pivotally connected to the table by means of bolts 34 passing through bushes in the arms and lugs on the table. The arms and shaft consist of a light casting. The shaft is provided with bushes 72 containing balls 71 which are retained by split washers and engage the coned ends of a screw 75 and a gudgeon 65 mounted in bosses 52. The gudgeon is mounted eccentrically and is turned to true the bail 30 with reference to the type-levers 17. The gudgeon is retained by a screw 80, and a pin co-operating with notches on the head of the gudgeon. The screw 75 is turned to take up play in the bearings and is retained by another screw 76. A slotted guide tongue 38 on the table enters a slot 39 formed in the segment 19 and having hard pins 87 at the ends. Two independently adjustable returning springs 56 for the universal-bar mechanism are connected to the pivots 34, and the ends 58 of rods 59 which are adjustably mounted in bosses 60 formed in plates 62 secured to the standards 49, 50. One of the plates has a stop-arm 64 for engaging a lug 40 on the table, the stop-arm being bendable for adjustment. Escapement mechanism comprising an escapement wheel 45, and a rocker 42 carrying fast and loose dogs 43, 44, is mounted as a unit on a bracket 100 which is inserted at the back of the machine and is secured by screws 101 to the standards 49, 50. A compact bearing for the escapement wheel consists of a bush 105 which is forced into a boss 106 on the bracket and is formed with races for balls 107, companion races being formed in a cone 108 on the hub 104 of the escapement wheel, and a cone 109 which is secured by a screw 110 to the hub. The rocker 42 is trunnioned on the coned ends of screws 113 mounted in the bracket and formed with a neck 115 for permitting the rocker to yield when the carriage is arrested. An adjustable stop for the loose dog consists of a cone 119 formed on a resilient rod 120 threaded into the bracket. A screw 41 on the rocker co-operates with the lug 40 on the table 31. Ink-ribbon mechanism.-A shaft 97 forming part of the feed mechanism is mounted in bearings 98, 99 formed on the bracket 48 and secured to the frame member 25 respectively, an arm 96 on the shaft being connected to a link which is detachably connected to an arm 94 on the shaft 37. Space-key actions.-The space key 123 operates the escapement independently of the universal bar by means comprising a rod 132 which is provided with a head 133 engaging the rocker 42 and passes through a sleeve 138 mounted in an arm 140 on the bracket 100. The sleeve has a head 137 for arresting the rocker and is threaded into the arm. The rod is threaded into a knuckle 131 connected by a link 129 to an arm 127 operated by the space key. The throw and normal position of the rocker are adjusted by means of the rod and sleeve. On disconnection of a screw 130, the knuckle and rod can be removed with the bracket. A spring 126 normally holds a stop 141 on the space key in contact with a ledge 142.