Patent GB-777719-A (GB)
Title: Improvements relating to signal selecting and permutation setting mechanism
IPC: H04L17/18
Filed: 1954-05-03
Abstract: 777,719. Printing-telegraph receivers. GRIFFITH, R. G. July 28, 1955 [May 3, 1954], No. 12811/54. Class 40 (3). In a printing-telegraph receiver for the selective setting of a number of permutation members by a member actuated by the received signals, an oscillatory sideways displacement is applied to a lever having a centrally located fulcrum so that one end of the lever operatively coacts with the signal-actuated member and the other end controls means to effect the selective setting of the permutation members in accordance with the sequential operation of the signalactuated member. In response to the start element of a signal the armature extension 204, moved upwardly by a spring 202, lifts a detent lever 144 clear of a bar 145 so that a spring 143 rocks a projection 141 on a lever 142 clear of a tooth 161 on a member carried on the receiver shaft 140. The member 144 is held out of operative relation with the armature extension 204 by the engagement of cam surface 206 with the upper surface of the bar 145. Towards the end of half a revolution of the shaft 140 a cam 158 rocks the arm 159 of the lever 142 so that the projection 141 is moved to the arresting position and the lever 144 is returned to its latched position. If the magnet 200 should be in de-energized condition when the lever 144 is moved back, the end of a pin 205, carried by the lever 144, engages the side of the extension 204 and the lever 144 is returned against the action of a spring 272 surrounding the pin 205 and mounted between ears on the lever 144. Cams 216 ... 220 on the shaft 140 allow latching levers 122 to move forward in sequence under the action of springs 226 so that associated levers 228 pivoted at 227 on vertical levers 230 move forward to cooperate with an extension 232 on the lever 210 pivoted on an axis 213 mounted in a frame 209 oscillated by a multi-point flutter cam 208 carried by the shaft 140. The lever 209 is moved downwardly immediately after a lever 228 has been allowed to move forward. If the magnet 200 is de-energized (space element), the extension 234 of lever 210 does not engage the extension 233 of the armature so that the extension 232 does not operate the levers 228 which return to their normal position with the member 221 still latched. If the magnet is energized by a mark element, the extension 234 engages the extension 233 and the lever 210 is rocked clockwise so that its extension 232 moves the corresponding lever 228 downwards and out of its latching engagement. The lever moves forward under the action of spring 231 on the lever 230 until a projection 235 engages a bail 236 carried by a pivoted lever 247. The lever 228 is rocked counterclockwise by the engagement of its cam surface 257 with the end surface of the lever 221 which moves back under the action of its cam 216 ... 220 and effects further anticlockwise rocking of the lever 228 so that its projection 248 is raised into the path of the bail 236. A shaft 237 released towards the end of half a revolution of the shaft 140 carries a cam 238 operating a space cradle 240 with an extension engaging the projections 241 ... 245 so that the members 221 which are latched move to the rear the associated levers 228 carrying with them the associated levers 230 having pins 246 located in notches in the permutation bars 3 . . . The cam 239 rocks the cradle 247 so that the bail member 236 engages the projections 248 on the unlatched members 228 which are moved to the left so that the associated levers 230 and their pins 246 move the associated permutation bars to the left. In a modification, Fig. 2 (not shown), bars corresponding to the levers 228 have two downward projections co-operating with one or the other of projections on pivoted T-members which are moved upwards simultaneously and are individually linked to the permutation bars. In a modification of the start-stop mechanism for the shaft 140, Fig. 4 (not shown), a lever operated by the detent lever 144, Fig. 1, has a pin-and-slot connection with a separate two-armed lever carrying the projection 141 and the pin on the arm 159 actuated by the cam 158.