Patent GB-190805760-A (GB)
Title: Improvements in Typewriting Machines.
Inventor: BROWN ALEXANDER TIMOTHY
Filed: 1908-03-14
Granted: 1909-03-15
Abstract: 5760. Brown, A. T. March 14. Typewriters.- Relates to the margin stop, linelock, bell, and carriage -release mechanism of typewriters. The various devices are shown applied to a f r o n t - strike machine employing type - b a r 42, 43 carried by segments 45,46, and operated by key-levers which are connected by rods 52 to levers 48 and links 47, the former being pivoted on a wire 50 in a segment 51 and having heels s 53 which operate a universal segmental bar 58. The bar 58 is suspended by links 60, 65 from arms 62, 67 on shafts 63, 68, arms 70, 71 upon which are connected by a link 72. The carriage feed comprises a rack 13 engaging with a spring-driven toothed wheel 14 and with a toothed wheel which gears with a pinion loose upon a shaft. The shaft carries an axially movable member 23, Fig. 1, which is adapted to clutch with teeth upon the loose pinion and is connected with suitable escapement mechanism. Bell-crank key-levers 37, 38, Fig. 1, pivoted at 36 support a yokebar 33, against which rests a roll 32 un the arm 31 of a vertically pivoted m e m b e r 27, 28. The depression of a key-lever 37 oscillates the arm 27 so as to release the member 23 from its clutch engagement with the loose pinion. The carriage is thus released from its escapement mechanism and may move under the influence of the wheel 14. The keylevers 37 have a limited movement. The margin stops are mounted on a bar 75 extending between arms 76 secured upon a shaft 77. The arms 76 may also carry a tabulator stop-bar 83. The stopbar 75 can be swung into a position above the platen 12 so that the stops may be adjusted on the bar with direct reference to the paper ; a scale may however be provided on the rear face of the bar. One or both hubs 78 of the arms 76 are shaped to be engaged by a spring 80, which tends to hold the arms in the position shown in Fig. 3. A stop 100 on a piece 86 determines the left-hand margin of the paper, and the carriage is arrested at the end of its letter-spacing movement by a stop 116 on a piece 87. The stop-pieces 86, 87 are of sheet metal bent at 88 to embrace the bar 75, and have ears to which are pivoted latches 91 adapted to engage teeth 90 on the bar. Ears 96 support the latch springs 98. The latches 91 are extended over the rear face of the bar 75, so that the stop-pieces cannot be removed from the bar until the latches have been first removed from their pivots. Both stops 100, 116 coact with a stop 101 pivoted at 103 in a rod 102, which is movable in its bearings 5, 6 towards the left against the action of a spring 112, Fig. 8, when the stops 101, 116 engage. An arm 126 on the rod 102 bears against an arm 123 of the pivoted bell hammer 118. Before the stop 101 meets the stop 116, it is lifted by a cam 115 on the stop-piece 87, thereby rocking the rod 102 to lift the bell hammer 118, which drops to ring the bell when the stop 101 is released by the cam. The stop 101 is notched to engage the stop 116, Fig. 7. A hook 133 on an arm 135, pivoted in the rod 102 and controlled by a spring 141, is caused by the endlong movement of the rod to engage beneath a short arm 132 upon a link 128 which is guided by a pin 131 and connected to the arm 70. The bar 58 is thus prevented from being moved rearwardly when a key is depressed. The arm 135 passing through the upper plate 4 limits the rocking movement of the rod 102. A line-lock release key 143 when depressed lifts a rod 151 which actuates an arm 152 to rock the rod 102 and release the hook 133 from the link 128, thus allowing additional letters to be written at the end of the line. The line-lock does not return to locking position. The rod 151 is beneath the arm 152 only when the line is locked. When the carriage is released by means of the keys 37, the arm 31 acts upon a lever 155 pivoted in the rod 102, Fig. 7, to withdraw the stop 101 from the paths of the stops 100, 116 against the action of a spring 106. The stops 100, 116 and cam 115 are bevelled on their reverse faces so that they may pass the stop 101 when the carriage returns after having been drawn to the right into the margin, or to the left beyond the line-locking position. The toothed ends of the latches 91 serve as indexes by-whicli the stops can be set with reference to the paper or to the scale on the bar 75.