Patent GB-1053531-A (GB)
IPC: B41J3/36
Abstract: 1,053,531. Typewriters &c. LOUIS MARX & CO. Ltd. Aug. 14, 1963 [March 13, 1963], No. 32126/63. Heading B6F. Type-bar machines; keys; key lever actions; keyboards.-Portable typewriter is provided with a keyboard having three rows of keys 70A, 70B, 70C, Fig. 2, each key comprising a lever 73 guided at its rear end 77 in a slot 103 of a guide comb 101 and articulated at its front end to a bell-crank 75A pivotally mounted on a bar 89. Depression of a key pivots the bell-crank 75A forwardly which actuates a respective type bar 55 for impression against platen 155. Depressed keys are urged into their upward position by a strip of rubber or foam rubber 105, disposed in a channel 106. Space-bar actions; letter-spacing arrangements; escapement mechanism.-Depression of a key or space-bar 80, Fig. 8 (not shown), causes the bell-crank 75A or upstanding arm 83, respectively, to urge a universal bar 100, Fig. 2, to be displaced forwardly, whereby links 171, Fig. 4 (not shown), articulated at their forward end to the universal bar pivot a cranked rod 185, Fig. 2, engaged in a slot 196 of a pawl mechanism 180 co-operating with a fixed and movable pawl 195, 210, respectively, with the teeth 190 of an escapement rack 177, attached to carriage 150 which is driven by coil spring 145 passed over pulley 148, Fig. 9 (not shown), and attached with its respective ends to the carriage and carriage mounting bracket 30 to lugs 154 and 42, respectively. Case-shift mechanism; case-shift key actions.- The type bars 55, Fig. 2, are mounted in a type segment 54, fixed to a bracket plate 57 adapted for sliding movement in slots 64 of an inclined support bracket 63 and urged upwardly by spring 66, Fig. 1 (not shown). The type segment 57, Fig. 2, is also attached pivotally to yoke members 68 articulated at their forward ends to pins 69 forming a pivot for the type segment during case-shift operations. Depression of a case-shift key 86, Fig. 1 (not shown), the lever 85 of which (Fig. 3, not shown) is attached to a cranked pin 114, displaces the type segment 57 downwardly by rocking the pin 114, Fig. 2, in a clockwise direction in a slot 52 of lug 51 integral with wall 34 of the carriage mounting bracket 30. Back-spacing arrangements; back-spacing key actions.-Back-spacing key 215, Fig. 18 (not shown), is pivotally mounted on a pin 216 and articulated through a pin-and-slot connection 221, 222 to an intermediate lever 225 having a lug 227, Fig. 21. Depression of the back-spacing key displaces the lug 227 downwardly, which in turn rocks a lever 230 in a clockwise direction and an associated lever 240 in an anti-clockwise direction the lug 245 of which engages the teeth 190 of the escapement rack 175 to back-space the carriage one letter space. Carriage-release arrangements.-The carriage rack 175, Fig. 12 (not shown), is integral with upstanding levers 173 having operating tabs 174 and pivotally mounted on pins 179. Rocking of the levers forwardly disengages the rack 175 from the pawls and allows free movement of carriage in both directions. Line-spacing arrangements; carriage-return arrangements.-Line - spacing and carriage-return lever 170, Fig. 9 (not shown), is mounted on a lug 159 to line space the platen 155 and return the carriage 150 at the end of line. Stops on the lug 159 limit the movements of the lever 170 in one direction and a wire link 167 connects the lever 170 to a pawl and ratchet mechanism 168. Carriage return movement stresses the coil spring 145 for escapement mechanism. Sound deadening arrangements.-Pawl mechanism 180, Fig. 10 (not shown), includes a movable pawl 210 mounted pivotally on a bolt 192 and spaced from a fixed bracket 143 by a spacer 193. Movement of the carriage brought about by pivotal movement of the pawl 210 is cushioned by spring 194 disposed about the bolt 192 and compressed during intermittent movement of the carriage in the direction of arrow. Alarms.-A bell 146, Fig. 9 (not shown), is struck by a spring-biased trip hammer 147 operated by a tab 153 on carriage 150 as end of line is approached. Platen roller brakes; paper, card clamping and guiding arrangements.-A coil spring 158, Fig. 9 (not shown), is disposed between a carriage lug 156 and platen knob 157 to act as a frictional lock to maintain the platen 155 in an adjusted position. Concentric, spring-urged paper guide 160, Fig. 2, provided with rollers 162 is pivotally mounted on paper bail 162, bent over tabs 164 serving as handles for swinging of the guide and insertion of paper. Ink-ribbon mechanism.-Ink-ribbon spools 110, Fig. 2, are mounted on shafts 115 passing through lugs 48, Fig. 4 (not shown), and terminating in gear-wheels 117 which co-operate with worms 118, Fig. 3 (not shown), on a shaft 120, whose ratchet-wheel 130 in turn co-operates with teeth 128 on a pawl member 125 reciprocated by the universal bar 100 to advance the ink ribbon 129 step-by-step. The ink-ribbon feed is reversed manually by rocking the shaft 120 through a knob 121 to bring one or the other gear-wheel 117 into contact with the respective worms 118. The ink ribbon is guided by guides 39, 39<SP>1</SP>, Fig. 2, forming extensions on an arm 40 integral with the bracket 47 and twisted about its vertical axis to the necessary guide position. The ink ribbon 129 is raised for impression by the ink ribbon vibrator 135 actuated by a rod 205 attached to the rocking pawl assembly 180 which rocks the rod 205 in a clockwise direction.