Patent GB-914750-A (GB)
Title: Printing telegraph apparatus
IPC: H04L17/24
Filed: 1959-05-01
Abstract: 914,750. Typewriters. TELETYPE CORPORATION. May 1, 1959 [May 13, 1958], No. 14895/59. Class 100 (4). [Also in Group XL (b)] In a printing telegraph apparatus in which a type wheel is mounted in a carrier on a shaft displaced from and parallel to a shaft rotatable to position the type wheel in the operation to select the character to be printed, the carrier is rocked about the rotatable shaft to impact the type wheel against a platen to print the character. The type wheel is provided also with a number of rows of characters, and the carrier is moved parallel to the axis of the rotatable shaft according to the row which includes the character selected for printing. Selector mechanism, Figs. 1, 2, 3, 4.-The signal impulses are applied to a magnet 15 having an armature 19, biased to the released or spacing position by a spring 21 and carrying an arm 24 with a transverse extension 84 co-operating with shoulders on marking levers 25, spacing levers 26 and a start lever 27 to hold in association with a flutter cam 28 the armature locked in its position in response to the incoming pulses, generally as described in Specification 676,825. The incoming start element releases the start lever 27 which through arm 82 engage bifurcated extension 81 of lever 74 rocked so that a lateral projection is moved out of the path of stop lug 73 of start-stop cam disc 66 secured to the shaft 58, the lever 74 being restored to the arresting position by the engagement of the projection 79 with the non-recessed portion of the cam. In response to the marking elements, the downward movement of the mark sensor 25 and of its extension 29 allows the corresponding selector member 32 . . . 36 to move downwardly when permitted to do so by the recess on the associated timing cam 61 . . . 65 so that the ends 88 of extensions 38 engage the notched ends 89 of pull bars 39 slidably mounted on a rod 41 and are moved upwardly by the extensions 38 when the member 32 . . . 36 is associated with the non-recessed portion of its cam. Each pull bar 39 has a projection 44 co-operating with a spring-biased latch 45 normally in engagement with a shoulder 48 in an extension of the associated selector bars 49-1 . . . 49-5, which on release move to the left and upwardly under the action of inclined slots 50 and springs (not shown). The pull bars 39 are restored to normal by a U-shaped bail member 93 having a T- portion 95 extending across the bars 39 and an arm engaging a reset cam 67 on the shaft 58. A cam 68 on the shaft 58 rocks an arm 67 which through stud 102 rocks arm 99 so that it is clear of the bail 102 and the bars 49-1 . . . 49-5 which have been unlatched can move to the left. The member 106 integral with the arm 107 also operates a toothed clutch, Fig. 2 (not shown), so that a cam 133 on a sleeve 128 connected to the shaft 58 rocks a bell-crank 138 connected to the shaft 103 so that the bail 102 in its leftward movement engages the shoulder 101 of the arm 99, and in its rightward movement moves arm 99 and bail 96 to restore any bar 49-1 . . . 49-5 which had been released to move to the left. The bell-crank lever 138 carries also an arm 139 for controlling the printing operation. Type selection and printing operation, Figs. 3, 7, 10, 11.-The bars 49-1 . . . 49-5 which control character selection are notched along their lower edges to permit the selection of function bars 152, Fig. 7, pivotally mounted on a rod 153 and supported in a cradle 156 which is raised after the reception of each code combination by a link 157 connected to an arm 158 on a shaft 159, Fig. 3, rocked by shaft 161 and cam 132 on the sleeve 128. Arms 212, 213, Fig. 7, controlled by the bars 49-1, 49-2 effect the axial positioning of the type-wheel 151 which is selectively rotated from a home position by arms 214, 215 and bars 49-4, 49-5 in one or the other direction, as in Specification 556,700, under control of the selector bar 49-3 and an arm 216. An arm 192 on a lever 188 rocked by the cam 133, Fig. 3, on the sleeve 128 engages an operating frame 193, Fig. 7, resiliently attached by a spring 194 to a slidable sleeve 173 secured to the type-wheel and the frame carries a projecting portion 226 which engages stops 221, 222, 223 selectively positioned by the arms 212, 213. If, for example, neither of the bars 49-1, 49-2 is raised, i.e. selected, the type-wheel is moved axially so that the projection 226 engages the stop 221. If either of the bars 49-1, 49-2 is raised, an integral arm 220 engages a lateral extension 224 so that the stop 221 is rocked out of the path of the projection 226, and the typewheel is axially positioned by engagement with stop 222 or 223. If both bars 49-1, 49-2 are selected, the stops 221 . . . 223 are removed and the type-wheel position is determined by the engagement of the projection 226 with a fixed abutment 232 in the type-wheel supporting carriage. The rotational position of the typewheel is determined by a gear-wheel 242 mounted on the shaft 173 and selectively rotated by rack members 239, 241 having extensions 243, 244, Fig. 11, engaging abutting portions of a cage or framework formed by members 235, 236, 237, Figs. 7 and 11, associated with operating extensions 233, 234 of arms 214, 215 rocked by the bars 49-4, 49-5 when selected. An arm 254 controlled by the third selector bar 49-3 has an extension 257 operating through an arm 258 to position a member 248 slidable on a shaft 249, so that a bail 247 is operatively engaged with a shoulder 245, 246 on the racks 239, 241, respectively. When neither bar 49-4, 49-5 and consequently neither arm 233, 234 is operated, the extension 243 (or 244) is arrested by the member 237. If bar 233 is rocked, arm 233 (or 234) is arrested by member 236, and if bar 234 is rocked, the arm 233 (or 234) is arrested by the member 235. If both bars 233, 234 are rocked the movement of the arm 243 (or 244) is limited solely by engagement with an edge portion 266 in the fixed frame 238. When, for example, the bail 247 is in engagement with the notch 246, the upward movement of the frame 251 in conjunction with spring 252 moves the rack 241 upwardly until the projecting arm 243 of the downwardly moving rack 239 engages a projection of the frame 235 . . . 237. On the reverse movement of the lever 188 a set-screw 253 engaging the frame 251 moves the rack 241 downwardly to restore the type-wheel 151 to its normal position, the rack 239 at the same time being moved upwardly. For rotation of the type-wheel in the opposite direction, the bail 247 engages the notch 245 so that the rack 239 is moved upwardly to rotate the type-wheel until the arm 244 engages an obstructing portion of the selecting cage 235, 236, 237. The printing action is effected by an arm 196 linked to arm 195 of the lever 188 and carrying a stud 204 engaging the arm 207 of a detent member 209 which is rocked clockwise to allow a spring- biased hammer 179 to impinge the type-wheel 151 against the platen 163. On the return, rightward movement of arm 186, the bail 197 is rotated counterclockwise so that it is latched by the detent 209 to hold the hammer 179 in its normal position. Case-shift operation.-The letter-shift and figure-shift signals provide maximum displacement of the type-wheel in the axial and the opposite rotational senses since the 1st, 2nd, 4th and 5th pulses of these two signals are marks. The lower-case and upper-case characters are carried by opposite circular portions of the type carrier 151, the normal housing position being at the centre of the letters semi-circle, and the housing position for the upper case condition being at the diametrically opposed position. The gear 242 which is rotated by the rack 239 or 241 to position the type-wheel 151 has an octagonal sleeve 273, Fig. 14, carrying a bevel gear 274 meshing with gears 277 carried on pin 276 on a sleeve rotatable on a shaft 271 carrying a second bevel gear 272 meshing with the gears 277. The shaft 271 is resiliently connected to the sleeve 273 by a groove 280 and detent balls held in position by a retaining member 283. When in response to the figure shift signal the type-wheel shaft 173, Fig. 7, has been rotated through approximately 90 degrees from its home position and the frame 193 carrying the shaft has been advanced its maximum axial amount the forward end of an extension 301, Fig. 12, engages the portion 303 of a hook member 294 which through a spring 292 rocks a lever 291 so that a ledge 299 is disposed under a sector member 281 secured to the sleeve 275. The lever 291 is also locked by a pivoted detent. On the return movement, when the wheel 242 moves anti-clockwise, with the sector 281 engaging the ledge 299 so that the pins 276 are held, the ball is moved out of groove 280 and sleeve 271 is displaced about 90 degrees relative to sleeve 273. Due to the rotation of gears 277, 272 a clockwise rotation of a further 90 degrees is imposed on sleeve 271 connected to the typewheel shaft 173, Fig. 12, which takes up a position 180 degrees from its home position in the lower-case group. When the member 193 returns to its lowest or home position, the arm 302, Fig. 10, strikes the arm 293, Fig. 12, of the lever 291 which becomes latched behind the shoulder 297 of the slide 295. The letters-shift signal rotates the sector 281 anticlockwise through 90 degrees from its position shown so that it is obstructed for return (clockwise) movement by the under-surface of the ledge 299, and in addition to this displacement of 90 degrees the type-wheel is given a further displacement in the anticlockwise direction when the wheel 242 is rotated to its normal position. Character-spacing; line feed; suppression of spacing, Figs. 7, 17, 19.-The type-wheel carriage is stepped by a cable 322, Fig. 17, passing around pulleys and with its ends attached to two drums mounted on a cylindrical tube enclosing a fixed rod on which is mounted a spring having one end fixed and the other end a