Patent GB-295496-A (GB)
Title: Improvements in automatic typewriters
IPC: B41J5/38
Filed: 1927-07-19
Abstract: 295,496. Evans, K. D., and Hooven, C. E. July 19, 1927. Strip - controlled type-lever machines. - The type-levers are moved for impression by means including a driving- member which is controlled alternatively by a perforated strip or the keylevers, the keylevers remaining stationarv when the typewriter is working under control of the strip; the strip or key-levers control also shift mechanism, positivefeed letter-spacing mechanism, and mechanisms for returning the carriage and traversing the carriage in tabulating. In the machine shown in Figs. 1, 3, and 9, the type-levers 18 engage sub- Tevers 23 having forks 26 engaging pins on actuating-members 28 supported by a rod 31 and bar 33, and guided by combs 29, 30, each actuating- member having spring-pins 37, 39, and an arm 36. The pins 39 co-operate with a reciprocating bar 50, secured to a rock-shaft 52, and with arms 15 on the key-levers 11, the arms having apertures which on depression of the keys permit the pins to rise into the path of the bar. The pins 37 co-operate with a perforated strip 42 and a reciprocating bar 45 rocking on a shaft 46. The .arms 36 co-operate with a reciprocating driving- member 53 secured to arms 54 on a rock-shaft 55. A driving-shaft 56 operated by a motor 57 is provided with eccentrics 60, 61, the eccentric 61 operating the driving-member 53 by means of a link 69, and the ecentric 60 operating the bars 45, 50 by means of links 62, 65. The strip passes over a cylindrical support 43 formed with a slot 44 for the bar 45. The strip is formed at the sides with feed-holes engaging sprockets 47 on the shaft 46, a ratchet-wheel 48 on the shaft engaging a feed-pawl 49 on the link 62. The shaft is mounted at the ends in one side of the framework 10 and in a projecting arm thereon, the arrangement enabling an endless strip to be passed on to the support. When the typewriter is operated under control of the strip the presentation of a perforation to one of the pins 37 permits the pin to drop into the path of the bar 45, and the associated member 28 is moved for. wards to bring the arm 36 into the path of the driving-member 53. When the member 53 descends, the member 28 rocks on the rod 31 and the associated type-lever is moved upwards for impression. The member 28 and the type-lever are returned by a spring 34. The key-levers remain stationary when the typewriter is controlled by the strip. When the typewriter is to be operated under control of the key-levers, stripfeed is suspended by releasing the pawl 49, a key for this purpose being connected by a link 68 to a lever 67 engaging the pawl. On depressing any of the key-levers, the associated pin 39 is permitted to engage the bar 50 and the typelever is actuated in the above-described manner. The pins 39 and arms 15 may be replaced by the arrangement shown in Fig. 13 and comprising a hook 126 pivoted on the key-lever 120 and normally resting on a lug 130 on the associated member 128 which co-operates with the driving- member. When the key-lever is depressed, an arm 127 on the hook rides over a reciprocating bar 131, and on release of the key-lever it is returned almost to normal position by a spring pin 123. The hook thereupon engages the lug, and the arm 127 is moved into the path of the bar 131, so that on forward movement of the bar the member 128 is moved forward and is then actuated by the driving-member in the abovedescribed manner. The key-lever has a lug 132 for limiting the movement of the hook. Platen-shift mechanism. - The shift-frame of the platen is connected to an actuating-member 28 which is controlled by a shift-key or the perforated strip in the above-described manner. Letter-spacing mechanism. - Positive-feed mechanism comprising a pawl driving a screw- and-nut device is provided for letter-spacing the carriage immediately after one of the type-levers has effected impression under control of the perforated strip or the keys in the above-described manner. The carriage 22<a>, Figs. 1 and 9, is provided with a non-revoluble threaded rod 73, Figs. 1 and 3, engaging a nut consisting of a pin on a sleeve 74 mounted in a bracket 82 on the framework. A ratchet-wheel 76 on the nut co-operates with a spring-urged pawl 76<a> carried by an arm 77 on the continuously operated rock-shaft 55. The pawl is reciprocated at each operation but is normally prevented from turning the ratchetwheel by means of a pin on the universal-bar frame 110 and a co-operating bevelled lug 115, Fig. 3, on the pawl. When the universal bar is in normal position, the lug rides under the pin and disengages the pawl, and on return of the arm 77 the pawl returns idly. When, however, one of the type-levers 18 is operated, the universal bar is moved rearwards and the pin is moved out of the path of the lug, thereby permitting the pawl to turn the ratchet-wheel and effect letterspacing during the return movement of the typelever. Space-key actions.-The above-described letterspacing mechanism can be operated by means of an actuating-member 28<c>, Fig. 1, which is controlled by a space-key or the perforated strip, and engages a rocking arm 116, Figs. 1 and 3, connected to the universal-bar frame 110. Carriage-releasing mechanism.-When it is desired to move the carriage by hand, the pawl 76<a>, Fig. 3, is depressed, and a detent is simultaneously released from the ratchet wheel 76 by rocking a finger-lever 117, Fig. 1. Carriage-returning mechanism. - Power-actuated carriage-returning mechanism is controlled by the perforated strip or a key. In the mechanism shown in Figs. 1, 3, and 9, a pinion 75 on the above-mentioned nut 74 engages a pinion 78 on a sleeve 79 mounted in the bracket 82 and geared to a shaft 84 having a bevel-gear 85. A bevel gear 87 splined on the continuously rotating shaft 56 engages a forked lever 90 connected by a link 91 to an actuating-member 28b controlled by the perforated strip or the carriage-returning key. When the member 28b is actuated, the gear 87 is moved into engagement with the gear 85, and the carriage is returned by means of the screw-and-nut device 73, 74. A spring pin 93 co-operates with a V-disc 92 on the gear 87 to retain the gears 87, 85 in engagement during return of the carriage. The gear 87 is disengaged by means of a lever 94 engaging a head 95 on one of the carriage-supporting rods 71, this rod being free to move longitudinally and being held in normal position by a spring 99. When the carriage has been moved to starting position an adjustable stop moves the rod 71 longitudinally and the lever 94 releases the gear 87. thereby arresting the carriage. Automatic means is provided for releasing or rendering ineffective the letter-spacing pawl 76<a> during return of the carriage. Tabulating-mechanism.- Power-actuated mechanism controlled by the perforated strip or a tabulating-key moves the carriage for tabulating, the movement being arrested by means of co-operating stops. In the mechanism shown in Figs. 1, 3, and 9, a bevel-gear 86, splined on the continuously rotating shaft 56, engages a forked lever 89 connected by a link 91 to an actuating-member 28a controlled by the perforated strip or a tabulating-key. The actuating-member is connected by a link 100 to a frame 102 mounted to rock and move longitudinally on the framework 10 and provided with an adjustable stop 107. When the actuating-member is operated, the gear 86 is moved into engagement with the gear 85 and traverse of the carriage is started. Simultaneously, the frame 102 is rocked, bringing the stop 107 into the path of a stop 106 on the carriage, and then receives slight movement longitudinally by means of a spring 105. A pin 103 on the frame thereupon engages the face of a plate 104 and serves to maintain the gears 85, 86 in engagement. When the stop 107 is engaged by the stop 106, the frame 102 is moved longitudinally to release the pin 103 and is then rocked by a spring 108, the gear 86 being thereby disengaged and the carriage arrested.