Patent GB-190300335-A (GB)
Title: Improvements in Typewriters.
Inventor: NEWTON PHILIP ARTHUR
Filed: 1903-01-06
Granted: 1903-05-28
Abstract: 335. Newton, P. A., [Blickensderfer, G. C.]. Jan. 6. Type-writers. - Re. lates to improvements in type-wheel machines, and particularly in those operated by power. Power drive. Enclosed in a casing 4 at the rear of the machine is a constantlydriven motor, preferably an electric motor. This motor drives a power shaft 5, which bears at one end the friction - wheels 181, 182, and at the other end a pinion which serves to drive a short shaft 9 journalled in the frame 7 and bracket 8. A singlerevolution face clutch, comprising the toothed elements 11, 15, is controlled by a slide bar 29 in such a manner that the forward movement of the bar produces a single counter - clockwise revolution of the cam 18, with which the slide bar 45 co-operates. The movement of the slide bar 45 effects the movement of the type-wheel to the impression point, and the bar being free from the cam is able to run slightly ahead of it towards the end of its stroke so that the type-wheel delivers a momentum blow on the paper. On its return, the chamfered face 46 engages with the straight side 19 of the cam and prevents any rebound of the latter. The bar 45 has a pin-and-slot connection with an adjustable plate 52, Fig. 2, secured to an upright arm 51 on a rock-shaft 50. The shaft 50 is normally rocked by the movements of the bar 45, a strong leaf spring 55 preventing any relative movement of the pin and slot excepting when some obstruction is met with in the working of the machine. Arms 49 extending from the shaft 50 carry a universal actuator bar 48, which is thus rocked forward and returned each time the controller bar 29 is shifted to operate the clutch. The rear end of the bar 45 is supported by the bell-crank lever 59, 60. and is prevented from hammering the cam 18 by means of the stop screw 62 and felt or leather washer 63. Action. The means by which the actuator bar 48 effects the operation of the type mechanism is shown in Fig. 7. The type-wheel 82 is carried by a spindle which turns in a support rigidly secured to a horizontal shaft 85. On each side of the said support the shaft 85 bears a sleeve 91 carrying a toothed sector 92. The toothed sectors engage on opposite sides of a pinion on the spindle of the type-wheel. Thus, if one sector moves rearwards, it turns the pinion and type-wheel, the pinion rolling on the other sector so that the support and typewheel swing towards the platen 123 at the same time that the type-wheel is being rotated. Each sleeve 91 carries a number of " tumblers " 95, one for each key in the corresponding half of the keyboard. With these tumblers engage toothed sectors 73 on operating-levers 67, to which are pivoted latches 65. The key levers 69 and operating- levers 67 are slotted to straddle the rock-shaft 50. When a key lever is depressed, the head 69<a> swings forward and the latch 65 is depressed so as to lie in the path of the actuator bar 48. At the same time, the shoulder 104 co-acts with the rib 103 to turn the rock-shaft 102, which, as shown in Fig. 2, actuates the controller bar 29 by means of a crank-arm 106. The cam 18 is thus set in motion, and the bar 48 swings forward, carrying with it the latch 65 and operating-lever 67. The tumbler 95 is moved slightly forwards until the notch 97 engages with the horizontal flange of the sleeve 91, and the tumbler and sleeve then turn together, none of the other tumblers being affected by the movement. The sector 92 causes the rotation of the type-wheel as above described. This rotation is controlled so as to bring the proper character to the printing position by the engagement with a bail 94 of a projection 100, the position of which varies inthe different tumblers. When the type-wheel has turned through a sufficient angle, the bail 94 is lifted, and a stop pawl 93 is thrown into engagement with a stopping-ratchet 87 and prevents further movement of the type-wheel. The sectors 92 and sleeves 91 are then compelled to move together, and the whole type mechanism swings over towards the impression point. A universal bar 79 tensioned by a spring 80 holds the operating-levers 67 normally in their rearward position. The gear teeth on the tumblers are formed on different pitch diameters, the smaller diameters corresponding to those characters which require greater movements of the type-wheel to bring the type to the printing position. By this means the movements of the operating-levers 67 can be made the same for all the characters. The typewheel is accurately positioned at the impression point by the engagement of a notched centering- wheel 88 with a fixed stud 107. The type-wheel is returned by means of a spring, and the front ends of the sectors 92 abut against a cushioned stop 110. The type-wheel is locked against rebound from the stop 110 by means of an arm 113 carried by the shaft 85 and co-operating with a projection 114 extending from a lever 117 which moves with the actuator bar 48. This locking-device is released the moment the bar 48 commences its forward stroke. In the modified form of " action " shown in Fig. 27, the rising arms 69 of the key levers normally engage e with the shoulders 278 of intermediate connectors 275 between the key levers and the rockshaft 102. the "action " differing in this respect from that shown in Fig. 7. When a key lever is depressed, the connector 275 is pushed forward and the nose 282 actuates the latch 65. The shaft 102 is at the same time rocked and the single-revolution clutch set in action. As soon as the operating-lever 67 begins to move, its tail piece 284 lifts the connector 275 clear of the key lever, and allows the rock-shaft 102 to return to the normal position. Another key lever may thus be struck before the first has been released. The type-wheel may be returned after an impression not directly by a spring but by means of a spring-tensioned roller acting on a reoesssd cam on the rock-shaft 85. The cam is so shaped that the shaft turns quite freely at the moment of impression, so as not to interfere with the momentum blow. The controlling-spring of the roller is, moreover, attached at one end to a part moving with the actuator bar 48, so that the spring exerts less effect during the impression stroke than during the return af the type-wheel. Carriage. The platen 123 is mounted on a carriage of any suitable construction. As shown, the carriage consists of rods 122 united by crossplates 121 and guided by wheels 125, 126, 127 of which the last named is journalled on a stud carried by an adjustable plate 129. Spacing and traversing mechanism. The spacing- mechanism shown in Fig. 1 comprises a carriage rack 131, feed-pawl 132, and detent-pawl 137. The feed-pawl is pivoted to a bell-crank lever 133, 134, the arm 134 of which can be rocked by means of pin-and-slot connection with a sliding plate 142. As the lever rocks back after displacement, the pawl 132 positively feeds the carriage forward The forward movement of the sliding plate 142 can be effected in two distinct ways. Whenever the type-wheel is moved towards the impression point, a short arm carried by the rock-shaft 85 effects the movement of the plate 142, and thus produces a space feed of the carriage. The plate can also be moved by an operating-lever similar to those marked 67, but without gear teeth, and actuated by the bar 48 under the control of a spacing bar or key. The mechanism is so constructed that if a character key and the spacing-bar are struck together the independent movements of the plate 142 are superposed, and the carriage moves through two spaces instead of one. Thus, at the end of a word, the double space can be produced at one operation, with an equivalent saving of time. The carriage can be returned at the end of a line by means of the power mechanism, which can also be used to feed it more slowly in the other direction. For this purpose the carriage is furnished with a rack 167, Fig. 1; with which engages a pinion 168 on a vertical shaft 169. This shaft is bevelgeared to a short horizontal shaft which bears friction-wheels 180, 179 adapted to engage with the unequal friction-wheels 181, 182 on the power shaft 5. The short horizontal shaft is journalled in a frame which can be slightly rocked in one direction by a key lever 187, and in the other direction by the key lever 188, the carriage being caused to return quickly and to feed forwards slowly by the respective keys. The third key lever 195 maintains both friction-wheels 180, 179 clear of the power shaft, and is depressed when the carriage is to be moved by hand. A universal frame underlies the three key levers and serves to move both the feed-pawl 132 and detent-pawl 137 clear of the rack 131. A finger lever 200 also releases the rack 131 from the pawls when pressed upwards. Fig. 29 shows a modified form of spacing- mechanism in which the carriage rack 131, Fig. 1, and pawls 132, 137 are dispensed with. The shaft 169 which bears the pinion 168 carries also a ratchet-wheel 305, with which co - operates a feed-pawl 306 which is normally clear of the ratchet-wheel. The pawl is pivoted to a carrier 307 loose on the shaft 169. The feed is effected by means of a lever 310 actuated by the movements of the bar 48, Fig. 2, and carrying at its upper end an antifriction roll which bears against the arm 309 of the pawl. Over - feeding is prevented by the wedging of the pawl at the end of its stroke between the ratchet-wheel and the block 315. The detent-pawl 323 is also normally clear of the ratchet-wheel, being held away from it by the lever 310. The detent pawl serves to prevent backward movement of the carriage on the return movement of the feeding-pawl, but at all other times the carriage is free to be moved either by hand or power in either direction. Keyboard locking - device. Superposition of characters at the end of a line is prevented by an automatic locking-device, which comprises a pin 205, Fig. 1, on the carriage,