Patent GB-260164-A (GB)
Title: Improvements in typewriting machines
IPC: B41J7/02
Filed: 1926-04-06
Abstract: 260,164. Block, G. K. April 6, 1926. Relay type-lener actions; letter-spacing mechanism.- In relay actions comprising means for returning the type-levers and locking them in normal position, the type-levers are connected to sliding rods which co-operate with locking-means and are released therefrom by depressing the keylevers ; the type-levers may be operated by springs, the letter-spacing mechanism being employed for returning the type-levers and tensioning the springs; or the letter-spacing mechanism may be employed both for operating and returning the type-levers. In the arrangement shown in Fig 1 each type-lever 5 is connected to an actuating-spring 10 wound on a rod 9 connected to the type-lever, the spring being normally in tension but being restrained by engagement of a lug 19 on the rod with a slotted guide-plate 20. The key-levers 23 actuate forked rods 22 engaging the rods 9. A universal bail 27 engaging cams 26 on the type-levers is secured to arms 28 pivoted to lugs 30 on a trunnioned rocker 31 cooperating with an escapement wheel 33 geared to the paper-carriage. The escapement wheel is urged to rotate by the carriage-driving spring or motor but is normally locked by a dog 36, Fig. 5, pivoted on the rocker and having a tooth 38 engaging a tooth 46 of the escapement wheel. The dog is adjustable by means of a stop 40. On slight depression of any key-lever, the associated rod 9 is released and the spring 10 swings the type-lever for impression, the rocker 31 being thereby depressed and permitting the dog 36 to release the escapement wheel. After slight movement of the escapement wheel, one of the teeth 46 engages a dog 45 on the rocker and the rocker is raised thereby causing the universal bail to return the type-lever .and re-tension the spring. Repeated impressions occur if the key-lever is held down. The dog 36 on releasing a tooth of the escapement wheel is swung by a spring 42 and when the rocker is raised the dog arrests the escapement wheel by engaging the following tooth. The leading faces of the teeth 46 are inclined to co-operate with an incline on the dog 45, and the rear and bottom faces also of the teeth are inclined to facilitate release of the dog 36. To provide for adjustment of the tension of the springs 10 they are connected to an adjustable slide 13 mounted in the guide-plate 48 of the rods 22 and secured by a pawl 16; in a modification the pawl engages the slide at the top. In the arrangement shown in Fig. 6, type-levers 58 associated with the abovedescribed key-levers 23, rods 9, 22, and spring 10, engage a universal bail 61 connected by a link 62 to a rocker 66 co-operating with an escapement wheel 71 driven by a spring drum 72. The rocker is formed with a diagonal groove 68 opening at one end into a slot, the escapement wheel being normally locked by engagement of one of the teeth 70 with the outer wall of the slot. When the type-lever swings for impression, the rocker moves rearwards, the tooth 70 is released, and the escapement wheel rotates, the following tooth then entering and riding through the groove and thereby returning to the normal position the rocker with the typelever and associated parts. In the arrangement shown in Fig. 8, the type-levers 79 are connected to rods 77 having hooks 80 normally disengaged from a hooked bar 86 connected to a rocker 88. A projection 99 on the rocker engages a groove 90 in a drum 91 connected to a spring drum 93, the rocker being normally locked by means of a stop 95 and a co-operating stop 85 on the bar 86. When any key-lever 23 is depressed the associated rod 77 is coupled to the bar 86, the bar is released and the drum rotates, thereby causing the rocker to swing the type-lever for impression. After the drum has rotated a quarter of a revolution, the movement of the rocker is reversed and the type-lever and associated parts are returned to normal position. A spring 97 normally retains the stop 85 in contact with a stop 96.