Patent GB-538473-A (GB)
Title: Improvements in ciphering machines
IPC: G09C3/00
Filed: 1939-11-06
Abstract: 538,473. Ciphering machines. HAGELIN, B. C. W. Nov. 6, 1939, No. 29464. Convention date, Nov. 12, 1938. [Class 146 (ii)] In a key-board ciphering machine with keys representing the characters to be coded or decoded, displacing mechanism for effecting the coding operation and means for indicating or reproducing the coded or decoded characters, the indicating or reproducing means are mounted upon a shaft combined with keyoperated stops, each stop being adapted to control the shaft at a position which corresponds to the primary character and forms the initial position for the coding operation. Depression of a key 33 rocks, through a roller 37 cn the lever 34, a catch 40, to release a corresponding bell-crank 43 whereby the upper end is swung into the path of movement of a cam 31 of a series arranged about a shaft 24 normally held against rotation. The shaft is connected by a slipping spring clutch to a gear-wheel driven from the main shaft 1 which is driven either manually &c. from a motor 13. The rear end of the depressed key lever actuates a universal bar 57 to rock a pawl and permit rotation of the shaft 1, the pawl being reset to interrupt the rotation after one revolution. The first stage of movement of the shaft 1 releases the shaft 24 and, under the influence of the spring, it is caused to rotate until stopped by the engagement of the cam 31 with the set bell-crank 43. The shaft is then relocked in position, and further rotation of the shaft 1 effects rewinding of the spring. The shaft 24 is connected to a shaft 30 carrying printing rollers 32a, 32b, and when the shaft 24 is stopped, the type on roller 32a corresponding to the key depressed is in printing-position. After a short period of rotation of the shaft 1 a lever 50 is rocked by a cam 52 to swing a beam 46 and reset in normal position the bell-crank 43. The shaft 24 carries a gear-wheel 65 driven by a gear-wheel 68 which is rotated by varying amounts to cause resetting of the shafts 24 and 30 whereby the roller 32b is set to print the secondary sign. The gearwheel 68 is actuated by bars 73 axially movable in slots in discs 71, 72 carried by the shaft 1, the bars only engaging the gear-wheel when projected beyond the disc 71. The bars carry projections 77 which act to release the shaft 24 for rotation, and projections 91 which co-operate with cam surfaces 90. The projections 91 are arranged in groups, so that any number of bars up to the number of characters on the rollers 32a, 32b can be projected into co-operation with the wheel 68. The cam surfaces 90 are rocked into or out of operative position by levers 83 carrying projections 85 extending into the path of rotation of pins 82 movable into operative or inoperative position as desired in discs 81 rotatably mounted on a shaft 80. The discs are connected so as to permit of independent rotation in one direction only to corresponding gear-wheels 92 having numbers of teeth with no common factor, and the wheels 92 are driven by gear-wheels 93 having an equal number of teeth and secured to a shaft 94 carrying a further gear-wheel driven the distance of one tooth at each rotation of the shaft 1. The printing-rollers carry on their peripheries two set of characters, one set 103 comprising only the letters and the other 104 the signs; in ciphering, the set 104 of the roller 32b printing the secondary characters are not employed, while during deciphering, the set 104 of the roller 32a printing the primary characters is not used. The rollers are slidable on the shaft 30 under the influence of a fork 164 controlled by a shaft 154. The paper is fed in web form over the rollers by means of feed rolls 116, 117. The former is provided with a ratchet-wheel rotated step by step by a pawl 119 connected to a spring-pressed lever 120, the other end of which runs on the periphery of a cam 124 on the shaft 1. Shortly before the shaft completes its rotation, the lever end falls into a depression in the cam to cause feed of the paper. In order to insert a space in the cipher after each five letters, the lever is permitted to fall a greater distance into the depression of the cam and so provide a two-tooth feed for the wheel 118. The movement of the lever is normally limited by a stop on a lever 128 spring- pressed into contact with a pin 134 on a further lever 131 pressed into contact with a cam 130. The lever falls into a depression in the cam at every fifth operation and so causes withdrawal of the stop and permits the lever 120 to fall farther. In the printing of the clear text the spaces are not required so withdrawal of the stop lever 128 is permitted or prevented by a recess in a bar 136 movable by a shaft 156 carrying a handle 157 which can be adjusted to positions for effecting ciphering or deciphering. The actual printing is effected by a hammer 108 on a lever 109 under the control of a cam 112 on the shaft 1. Spaces in the clear text are replaced in the cipher by a letter corresponding to X, so that on depression of the space bar the X key is depressed. This causes the presentation of a gap 149 in a disc 138 or 139 attached to the type wheel opposite the end 141 of a lever 140 having an extension engaging a cam 142 on the main shaft. The lever is therefore permitted to rock and raise a stop lever 143 into the path of movement of the lever 109. Although the signs on the set 104 may be used in the clear text, they do not appear in the cipher, but a letter, e.g. the letter corresponding to Z in the clear text, must appear in the cipher to indicate that signs are being printed. The shift key is therefore connected to the Z key, and its operation causes a gap 176 in the disc 138 or 139 to be presented opposite the end of the lever 140. The gap is deeper than the gap 149 and causes a stop 177 on the lever 143 to swing in front of an extension of the lever 120 to prevent the operation of the paper feed of the clear text. At the same time, the rear end of the lever 140 strikes a bell-crank 174 causing its upper end to move forward and push outwardly one of two pins 166, 167 mounted in the end of an arm 165 attached to the shaft 154. When the pin is pushed forward, it lies in the path of a cam 169 on the main shaft 1, the action of the cam being to rock the arm 165 and consequently the fork 164 to slide the printing rollers along the shaft 30. A cam 171 resets the pin towards the end of the rotation of the shaft When the handle 157 is in ciphering position, a cam 155b on the shaft 156 maintains the arm 153b of the secondary type wheel 32b beneath the lever 140b to permit the letter X to be printed, and the secondary arm 165b is held against movement to prevent the signs from being printed. In deciphering, the cam 155 holds the arm 153 in position under the lever 140 to permit printing of the letter X, and an arm 183 connected to the arm 153 prevents rocking of the arm 165 while the arm 165b is free for operation. Specification 455,333 is referred to.