Patent GB-190428745-A (GB)
Title: Typewriting Machines.
Inventor: MILLS BENJAMIN JOSEPH BARNARD
Filed: 1904-12-29
Granted: 1905-08-24
Abstract: 28,745. Mills, B. J. B., [Williams Typewriter Co.]. Dec. 29. Type-writers. - Relates more particularly to front-strike machines. (1) Type-bar actuating mechanism, Fig. 1. To the key-levers 1 are pivoted at 2 links 3 provided with slots engaging pins 5 on bell-crank levers 6 pivoted in supports 27 on the fixed frame 8. Each link 3 is formed with an extension 10 having a rounded nose 11 engaging the lever 6 at a greater distance from its pivot than is the pin 5, so that when the key 1 is depressed the nose 11 first operates to move the lever 6 and type-bar, until the end of the slot engages the pin 5, after which the movement of the type-bar is accelerated. The levers 6 are connected to the type-bars 15 by rods 14. The bars 15 are pivoted in hangers or brackets, each of which is formed by two plates secured together with a distance-piece between. The plates are formed with recesses to reduce friction. The links 3 are folded at 10 so as to straddle the lever 6, and the latter are pivoted in U-shaped brackets 27, and so shaped and arranged that their upper ends are in an arc of a circle, and are adapted for interchanging so as to change the location of adjacent type-bars if desired. (2) Aligning-devices. As the types strike, they are aligned by means of a hole 28 in the type-bar 15, Fig. 12, engaging a pin 29 of spherical, acarn, or like form, attached to a plate 31 and extending through an opening in a rebound spring 30. The hole 28 is curved to the radius of the type-bar, so that the pin 29 at its greatest diameter engages and fits when at any part of the hole. (3) Paper carriage, and line-spacing devices. Fig. 15 shows an end view of the carriage, and Fig. 19 a sectional view. The platen 35 is mounted in a vertically-movable frame 59 for effecting the shift of the platen, and the weight is partially counterbalanced by springs. Line-spacing is effected by a sliding pawl 37 engaging the ratchet-wheel 36 on the platen, one end of which is provided with rack teeth 39 engaged by a pivoted segment having an operating- lever 42. The pawl is pressed into engagement by a spring 38, and its movement is limited by a stop-pin 44, carried by a pivoted arm 45 and held in position for one, two, or three &c. line-spacing by a spring latch 49 having several notches 46 for engaging the pin. A paper table 54 extends under the platen, and is formed with a recess 55 for the transverse bar of a pivoted frame 87, when the latter is out of use as shown. Pressure rollers at the rear side of the platen are carried by springs. In the frame 59 is pivoted at 62 a segmental brake shoe 61 pressed by a spring 63 against the cylindrical end of the platen. On the spring 63 is a detent roller engaging the ratchetwheel 36. For retracting the brake shoe 61, a short shaft 67 having a milled head is journalled in the shoe, and is provided with a cam engaging a fixed pin on the framing. The detent may be lifted from the wheel 36, without disengaging the shoe 61, by a turn of the shaft 67, which is formed with a flattened portion on which the spring 63 normally engages. Pressure rollers 71 at the front side of the platen are carried by a tubular shaft turning on a shaft 73 having cams on its ends for lifting the rollers. The shaft 66 of the platen is connected by a clutch device with a co-axial short shaft having a knob for turning the platen. The clutch device may be disengaged for removal of the platen. Elastic margin or column guides 85 are fitted to slide on the horizontal scale-bar 86. When very stiff paper is used, it is held to the platen by the frame 87, which is then turned forward on to the platen over the paper. (4) Spacing and carriage-controlling mechanism, Figs. 22, 24, and 28. On the carriage 59 is a rackbar, engaging a spurwheel 97 on a shaft 96, and also a pinion 109 geared by a pinion 106 with the wheel 97. These wheels and the escapement are mounted in a removable frame 91, held in its adjusted position by clamps and pivoted wedge - like bolsters. These bolsters raise the frame into operative position against the clamps. On the shaft 96 is mounted the spring drum 98, provided with a ratchet winding-arrangement. On the frame 91 is a stop lever 113, which may be turned into position to engage a pin 112 on the wheel 97 to lock the machine, and to prevent sudden unwinding of the spring when the frame 91 is removed from the machine. On the frame 91 is a bell 114, and a hammer tripped by a projection on the carriage. The bell-hammer frame is operated through the medium of a lever and pin, so that the carriage operates it only in one direction of its movement. On the shaft of the pinion 109 is loosely mounted an escapement wheel 123, coupled to the shaft by a ratchet and pawl device, so that it moves with the wheel 109 in one direction only, thus permitting the ready return of the carriage. A dog-rocker 129 is pivoted at 127, 128 in the frame 91, and carries a fixed dog 131 and a movable dog 132. The dog 132 is pivoted at 133, and is also pivoted or arranged to be movable laterally by a releasing-arrangement 159, 160, 162, 163 to disengage it from the wheel 123 and free the carriage. The dog 132 is pulled by a spring 134, and is moved by the wheel 123 back against a buffer 145 on an arm 146, which is pivoted at 147 and sustained by a spring 152, the tension of which may be regulated by a cam 153. A modified buffer arrangement is described. The position of the buffer may be adjusted by a cam-stop 150. The teeth of the wheel 123 and of the dog 132 are bevelled on the sides on which they engage each other as the dog rocks back into engagement. The rocker 129 is held against the stop 191 by the returning-spring 190, and is rocked by means of a lug 204 engaging the pin 130. The lug is on a plate 203 fixed on a link 201 which is connected to an arm 208 operated by an arm 207 and a universal bar 206 engaged by hooks 205 on the links 14 which operate the type-bars. The link 201 has a finger 200 engaged by a loop on a rod 197 operated by an arm 196 on the space-key frame 195. (5) Platen-shifting mechanism, Fig. 41. The platen frame 59 is carried by parallel-motion links 210, from which is suspended a frame 211 carrying a wheel 212 running on a track bar 214, on which it is guided by the parts 216, 217. Legs 215 supporting the track are adjustable in length by screws 218, 221, the lower ends of which are formed with knifeedges resting in recesses in levers 224. Latches 229 formed with curved projections engaging holes in the legs prevent displacement of the legs. The levers 224 are connected by accelerating-links 232 to the shift key-levers 231. These links are formed from blanks, bent over to embrace the ends of the levers 224, one leg being bent to pass through a hole in the lever 231 and engage a hole in the other leg. The holes are formed with convex upper and lower sides to permit of free movement without loss of motion. When a lever 231 is depressed, the outer end 233 of the link first acts on the lever 224 and afterwards on the inner end 235. A screw 238 passed through the lever 224, and engaging a slot in the link, holds the latter in place. The upward motion of the platen is limited by inclined stops 247 engaging stop-pins 249, adjustable in posts 248 by screws 250, 252. The shift levers 231 are connected by the pivot bar 244 so that they move together. They are formed with the usual keys 253, and are also provided with locking-keys 257 pivoted at 259. The key 257 carries a rod 263, lying under the lever 231, and this rod moves a latch 254 pivoted at 255 on the lever, causing it to engage under a retaining-piece 266 and hold the lever in its depressed position when it is depressed by the key 257. It may be released on depressing it by the key 253, the latch 254 being returned to its inoperative position by the spring 265. The retainer 266 is pivoted at 267 and is adjustable by means of a cam 271. (6) Ribbon mechanism. The ribbon passes from one spool 298 to the other, and also passes between two pairs of feed-rollers 304, each pair being geared to the adjacent spool by gearing 312. Each spool 298 rests on, and is driven frictionally by, a friction disc 296 on the shaft 295, so that the spool winds up the ribbon fed to it by the rollers 304. One or other of the shafts 295 is driven by bevel gears from a transverse shaft 279, movable endways to put either shaft 295 in gear, and reverse the feed. In the hub of each spool is a spring-pressed lever to which the end of the ribbon is secured, and which, when the ribbon is all unwound, operates to depress a sleeve 326 against the pressure of a returning- spring 327. A cam-surface on the sleeve 326 operates a lever 330 connected by a link 332 to a plate 334 which is pivoted at 336 on a pivoted frame 335. The plate 334 is thereby raised into position to be engaged by a shoulder on a universal frame 276, and is moved to the right on the next operation of a key 1. All the keys 1 operate the bar 275 of the frame 276. Each plate 334 is connected by a rod 339 to a bell-crank lever, which operates to move the shaft 279 longitudinally to reverse the feed. One feed roller of each pair 304 is carried by a lever 308 operated, to raise the roller of the inoperative pair, by a wedge rod 344 connected to each plate 334. The shaft 279 is driven by ratchet gear, the pawl-arm of which is rocked by an arm on the universal frame 276. The shaft 279 may also be moved by hand to reverse the feed when desired. A housing 298<1> surrounds each spool. A means is provided for moving the ribbon over the printing point at each depression of a key, and also for initially raising the ribbon each time the platen is shifted. The ribbon-guide is mounted to slide, and is moved by bell-crank levers &c. operated by a rod connected to the universal frame 276. The connection between two of the levers comprises slots in the levers, engaged by an antifriction roller connected with a pivoted frame moved by