Patent GB-794091-A (GB)
Title: Improvements in or relating to printing telegraph apparatus
Inventor: HANDLEY JOHN
IPC: H04L17/00
Filed: 1954-01-25
Abstract: 794,091. Typewriters &c CREED & CO., Ltd. Jan. 21, 1955 [Jan. 25, 1954; Feb. 19, 1955], Nos. 2118/54 and 4872/54. Class 100(4) [Also in Group XL(b)] In printing-telegraph apparatus, a typecarrier is selectively positioned by the operation of a motor driven cam sleeve in conjunction with the operation of control members which are selectively set in accordance with the response of an electromagnet to received code combinations or by mechanical means under control of a keyboard. Two sets of control members are employed so that whilst one set is being used to position the type-carrier, the other set is operated in accordance with the subsequent character or signal combination. When the start element is received, the armature 1 operates links 4, 5 to rock a shaft 3 carrying an arm 25 engaging an arm 26 of a lever so that a pawl 28 is raised to release a clutch 7 allowing a cam sleeve 29 to be driven through gears 12, 13. An arm 49 attached to the shaft 3 permits a roller 47 to fall into one of five successive recesses in a cam 32 in response to spacing elements of the code combination so that a pecker 33, Fig. 4, having upper and lower projections 50, 60 is effective to set plates 34, 36...42 or 35, 37...43 of the two groups made operative respectively for successive signals. The plates of the two sets are alternated and the projection 50 is spaced from the projection 60 by a distance equal to that between successive plates of the same set, i.e. twice the spacing of successive plates. During the setting of one set of plates by projection 50, the lower projection 60 passes under the projection 59 of that set whilst during the setting by projection 60 at the time of striking of a projection 59<SP>1</SP> of a plate e.g. 39 in response to a space element the projection 50 will pass over projection 591 of 37. The pecker 33 is traversed across the array of plates 34...43 by an arm 55 connected by links 52, 53, 54 to an arm 51 operated in steps by a traverse cam 31. At the commencement of rotation of shaft 29, a cam 30, Fig. 2, for releasing the clutch controlling the printing mechanism forces outwardly a roller 61 carrying an arm 62 which moves downwardly and a pin 64 engages a projection 65 on an arm 66 to rock a shaft 67 so that its opposite end 68, Fig. 3, raises a bar 69 with an opening 70 which engages a tooth 71 of a member having a projection 23 normally engaging a finger 20 of a clutch control mechanism. When the roller 61 falls into the recess of the cam 30 towards the end of the revolution of the shaft 29, the bar 69 is pulled downwards and the projection 23 is rocked clear of the finger 20 so that the clutch 9 operates to allow the printing shaft 19 to be driven for one revolution. During its downward movement the bar 69 is cammed outwardly so that the toothed member is free to rotate and restore the projection 23 to its arresting position. Soon after the commencement of rotation of the shaft 19 resetting levers 92 are moved to the left and towards the end of the revolution are moved to the right to reset the plates of the set used for printing a character or performing a function. Also, early in the rotation of the shaft 19 either cam 94 or 95 engages respectively an anvil 96 or 97 to move the storage unit to the left or right so that a set of plates can be read for the printing operation, and the set of plates used for the previous selection and restored during the previous rotation of the shaft 19 can be selectively set by the next incoming signal. Also a cam on the shaft 19 raises frame members carrying pins 77, 78 engaging notched plates 79-83 so that after the set of control plates 34, 36...42, or 35, 37, 43 has been shifted the plates 79...83 are selectively set by engagement of their members 144 respectively with the raised or cut away portions 145, 146. The setting of the plates controls the inward movement of the bars 162...169 allocated to various functions and control signals such as "Bell", "Who are you?" In addition, each plate carries an operating member 149 which is effective to close contacts carried by members 147, 148, 150 operative when the keyboard is operated to send code combinations of current impulses. Type-wheel positioning mechanism. The type-wheel 129 is rotationally and vertically set by aggregate motion mechanism controlled by rocker levers 99... 103, Fig. 4, associated with the selectively set control plates 34, 36...42 or 34, 37...43. The projection 262 on a rocker 99 when not held by an operated plate is able to move a distance of 3 units so that its end attached to link 111, Fig. 1, can move 4 units. The remaining rockers 100...103 can drop 6 units when not blocked by associated control plates so that their free ends attached to links 112...115 can move 8 units. Links 111, 112 are connected to a first summation rocker 116, the centre of which and the end of link 113 are connected to a second summation rocker 117. The centre of rocker 117 is pivoted midway between the centre and an end pivot of an arm 118 connected by a link 119 to a cross arm 120, the centre of which is pivoted on a rack 121 and pulled by spring 109 disposed under link 119. The selective operation of the rockers 99-101 effects rotation of the type-wheel through 0 to 7 units of rotation. The rocker 102 effects reverse rotation of the type-wheel through 8 units, so that a total of sixteen positions are obtained. The fifth racker 103' moves link 115 eight units and operates a third summation rocker 132 to move rack 133 rotating gears 134-139 to lift the vertical rack 140 and to raise the type wheel for a second row of types as selected by rockers 99 to 102. The correct vertical and rotational positions of the type-wheel are ensured by detent members engaging recesses in a vertical rack on the type-wheel carriage and the space between teeth of the bevel wheel on the type-wheel shaft. Printing operation. After the operation of the rockers 99-103, a printing cam 151 lifts a lever 152 and the end 153 is pressed down so that the frame 156 is pivoted about the shaft 157. When the roller 159 engages the step 158 of the cam 151, the end 153 of the lever 152 moves up rapidly and the type-wheel 129 moves sharply to the right and prints the selected character. Suppression of printing operation. When a function is selected one of the bars 162... 169 moves inwardly and an upstanding pro... jection 183 engages the side of a notch in a plate 177 pivoted on a shaft 180 and having a re-entrant portion engaging a pin 175 on an arm of a frame 172 pivoted at 173. The frame has a pawl 170 latching with a pawl 171 on the lever 152. When printing is to be effected, the plate 177 moves downwardly under control of its cam and the re-entrant portion engaging the pin 175 rocks the frame so that the pawls 170, 171 are disengaged and the roller 159 is able to drop and rock the arm 152. If one of the bars 162...169 is selected, the plate is prevented from dropping when the cam permits it to do so and the pawl 170 is not rocked out of engagement with the pawl 171 so that the end of the arm 152 is prevented from moving and effecting the printing operation. Spacing on printing. The frame 172 has a projection 176 engaging a pivoted lever 178 connected by a link 187 to a vertical lever 188. When printing takes place the lever 178 is rocked so that the vertical-lever 188 is moved to the left and a tooth 193 moved under the end 191 of a rocker 190 which is actuated to move the lever.188 downwardly and through rockers 194, 195 to rotate shaft 196 carrying a fork 197, Fig. 3, pulling down a lever 198 which thrusts a pivoted pawl 199 against the teeth of guide rail 200. Case shift. The selection of the function bar 167 allocated to figure-shift moves lever 229 clear of rocker 141, Fig. 3, so that link 143 operates the rack 133 and lifts the type-wheel 129 to print figures until the lever 229 is restored. The bar 169 operated in response to the letter-shift signal pushes lever 229 back to its normal position to prevent operation of rocker 141 so that link 143 does not operate the rack 133. Line-feed. When the bar 164 is selected, a link 221 is moved so that it is engaged by a rocker 228, Fig. 3, and moved downwards. Link 222, Fig. 2, moves downwards and operates rocker shaft 223 pivoted on a pin 224 and actuating upwardly a pawl 225 which engages a ratchet wheel 227, shown in Fig. 1, and rotates the platen roller 226. Double spacing may be obtained by moving a lever 426, carrying the pin 224, to the left. Carriage return. The fourth bar 165 is operated and causes link 207 to be moved into engagement with rocker 210 and to be raised by cam 217. Link 207 causes rockers 194, 195 to turn shaft 196 in the direction opposite to that for letter-feed and lever 198 is pushed up.'A projection 289 on a pawl 199 lifts arms 290 associated with locking projection 201 so that it is clear of the teeth on the rail 200. Pressure of the projection 289 on arm 290 keeps pawl 199 out of engagement with the teeth on rail 200 and the carriage returns under the action of a spring drum. The return of the carriage to its initial position is damped by a plunger engaging steel shot in a container. Specifications 794,093 and 794,094 [both in Group XL(b)] are referred to.