Patent GB-190429336-A (GB)
Title: Improvements in Type-writing Machines.
Inventor: CLARK WILLIAM
Filed: 1904-12-31
Granted: 1905-03-09
Abstract: 29,336. Clark, W., [Underwood Typewriter Co.]. Dec. 31. Type-writers.-Relates chiefly to the escapement mechanism, reversible ribbon-feed mechanism, tabulating-mechanism, carriage-shift mechanism, keyboard-locking mechanism, and the carriage of type-writers. The type-bar action consists of keylevers 2 mounted on pivots 3 and having pin-andslot connections with elbow levers 5, which are connected by links 8 to type-bars 9. The levers 5 are removably pivoted on a pin 6, and are held in position by a locking-bar 7. To receive the pivot 11, each type-bar has an opening which is closed by a spring-actuated latch provided with a handle. Each key-lever has a toe 2<a> which engages a universal bar 15 supported by links 16. The bar 15 is connected by a bar 17 with a cross-bar 18, which is pivoted to the frame and carries a pawl 19 which engages an escapement wheel 20. A projection on the bar 17 also actuates a spring- controlled stop-pawl 23 when the universal bar is moved rearwards. The escapement wheel 20 is mounted on a shaft 21 carrying a loose pinion 26 which gears with the rack 27 on the rear part 28 of the carriage. The pinion 26 is caused to turn with the shaft 21 in the feed direction by means of a plate fixed on the shaft and carrying a pawl which engages the pinion. The carriage can thus be returned at the end of a line without rotating the shaft 21. The carriage is fed by means of a spring, one end of which is connected by a tape to the carriage. The carriage consists of a front portion 31 carrying the platen 32 and a rear portion 28, both of which are pivoted on a rod 33. The front portion of the carriage has rollers 34 which travel on a rail 35 carried by the shift-frame 36. Pins on the rail 35 are received loosely in openings in the frame 36 so as to allow the rail to remain vertical when the frame is tilted. The shift-frame is supported on knife-edges, and the weight of the carriage is balanced by means of a spring. The shaft 21 is caused to feed the ink ribbon by means of a pawl carried by a disc on the shaft and engaging with a loose pinion 39. The pinion 39 is connected by a spur-wheel 40 and bevel-wheel 41 with a bevel-wheel 42 which drives a shaft 44 by means of a feather-and-groove connection. The shaft 44 carries at its ends two bevel pinions 47, Fig. 11, either of which can be connected by means of bevel-wheels with the shaft 52 of one of the ribbon spools 53. The ribbon passes through a guide 56 which is moved up, at each depression of a key, by a pivoted lever 57 having pin- and-slot connections with the bar 17 and with an elbow lever 59 carrying the ribbon-guide. To enable the direction of the ribbon-feed to be reversed, the shaft 44 is provided near each end with a collar which is engaged by a forked arm 62 on a shaft 63. Springs 64 tend to throw these arms 62 towards each other, but they are held stationary by latches 65 projecting into the path of arms 66 on the shafts 63. The latches 65 are mounted on shafts 67, and their motion is limited by means of forked portions embracing members 69 of the machine frame. Each shaft 67 carries at its upper end a ribbon guide 71. Near each end of the ribbon is secured a metal loop or projection which cannot pass through the guide 71. The shaft 67 is thereby rotated, the latch 65 releases the arm 66, and the arm 62 moves the shaft 44 longitudinally, reversing the direction of the ribbon-feed. The arms 62 may be brought back to their initial position by the carriage-shift mechanism. To prevent accidental movement of the shaft 44, a spring-pressed ball located in one of the bearings 46 engages one of two grooves in the shaft. The tabulating-mechanism consists of a key-lever 73 connected by a link 74 with a lever 75, the rear end of which engages a transverse lever 77 connected with a vertically-movable stepped or other stop 79. This stop engages with the pivoted member 80<a> of one or more column stops 80 mounted on a rod 81 fixed to the carriage. A toe 83 on the stop engages with a rack on the carriage to hold the stop in position. A spring 85, Fig. 10, throws a ball 86 towards a plate 87 having a rib, so that the toe 83 is held either in or out of engagement with the rack. One of two pointers 89, 90 indicates the position of the stop on a scale 91. The carriage is released from the escapement for tabulating purposes by an arm mounted on the fulcrum of the lever 75 and carrying a roller which bears against the rack 27 and is adapted to press it out of engagement with the pinion 26 and against a brake-strip 95. In order to shift the platen for printing capitals, the shift-frame 36 is pivoted at each side of the machine to a lifting-bar 96, Fig. 14, the lower end of which is engaged by a pin 97 mounted eccentrically on a disc carried by a shaft 98. A pinion 100 on one end of this shaft gears with a toothed sector 101, Fig. 4, fixed to a shaft 102, the other end of which carries an arm 103, Fig. 1. Shift-keys 104, 105 engage the arm 103 and the sector 101 respectively. When the key 104 is depressed, the carriage is held in its upper position owing to the engagement of a latch 106 with a pin on the sector 101. To allow the carriage to fall to its lower position, the key 105 is depressed and a pin 105<a> releases the latch 106. To enable the carriage-shift mechanism to be used for setting the ribbon-reverse mechanism, the lift. ing-bars 96 are provided with pivoted hooks which engage the arms 66. To enable the carriage to be removed easily, the rod 33 has at each end a recess 33<a>, Fig. 3, in which is a pin which is engaged by a fixed slotted support 109. To lock the rod 33 in position, a latch 110 is moved vertically to fill up the space between one of the supports 109 and the end of the recess. In order to lock the carriage at the end of a line, the rock-shaft 113 which carries the bell-trip and hammer is provided with a lug. After clearing the bell-trip, the margin stop engages this lug and moves the shaft 113 longitudinally. A pivoted lever 114, Fig. 1, is thereby moved so that its lower end is in the path of the stop-pawl 23. To release the carriage, a key 117 is pressed in, whereby the shaft 113 is rotated, and a spring restores the lever 114 to its normal position.