Patent GB-191415550-A (GB)
Title: Improvements in and relating to Printing Telegraph Apparatus.
Inventor: ALEXANDER ALBERT EDGAR
IPC: H04L17/22
Filed: 1914-06-29
Granted: 1914-11-19
Abstract: 15,550. Alexander, A. E., [Union Switch and Signal Co.]. June 29. Type-printing telegraphs.-The levers of a typewriter are selected by means of a permutation bar mechanism, each of the six bars being movable by a magnet which moves a driving-pawl into engagement with the bar. Some of the selected levers are used for linespacing, carriage-return. calling the operator, and change of case. Selecting mechanism, Figs. 1, 2, 3, 4, and 9. Each of the permutation bars B is controlled by a magnet S, which is energized from a distributor contact. The armature 25, 26, Fig. 4, of an energized magnet S pushes the rod 27 forward, and thus causes the arm 29<b> of the three-armed lever 29<a>, 29<b>, 29<c> to engage with the notch 37 in a bar B. The notches 37 are slightly undercut so that the arms 29<b> remain in engagement with them, and the third arm 29<c> is latched by a hook 36. After the combination of magnets S has been energized, an impulse is sent to the magnet 38, Figs. 1 and 2. The armature of this magnet depresses the lever 54 through the rod 53, thus releasing the disk 51 from the pawl 91. The disk 31 carries a series of pins 47 touching balls 48. which rest in notches in a block 46 and are pressed by springs 50 against the cup 45. The wheel 5 is integral with the cup 45 and is driven from the motor M through the gearing 4. When the pawl 91 is removed from the disk 51, the balls 48 are pressed against the cup 45, and the shaft 10, which carries the disk 51 and block 46, is rotated. At the end of one revolution of the shaft, the pawl 91 again engages the disk 51, and the pins 47 press the balls 48 inwards against the springs 50, thus releasing the clutch. The shaft is held from backward movement by the pawl 59 engaging with the disk 58 on the shaft. The shaft 10, which thus makes one revolution after the magnets S have been operated, carries a cam 15 which, through the roller 17 and arm 32<a>, moves the levers 29 to the right in Fig. 4, and causes those of the levers 29 that have been actuated to move their permutation bars, which remain in actuated position by friction. One of the spring-pressed levers 62, Figs. 1 and 2, is thus enabled to fall into a slot in the bars; but near the end of the revolution of the shaft 10, a cam 14 restores the bars through the roller 16 and lever 39, the levers 62 being pushed back by the return movement of the bars, as each bar is provided with a number of slots having bevelled edges, as shown in Fig. 9, and one of those bevelled-edge slots is included in every selecting combination. After the swell of the cam 17 has been passed, the spring 44 acts on the arm 32<a> and returns the levers 29<b> to normal position. Type-printing mechanism, Figs. 1, 2, and 5. The selected lever 62, Fig. 2, is pulled by its spring 67 beneath a lever 81. The set of levers 81 is supported on a rod 76, and the levers are pressed by springs 69 against the underside of a rod 74. The rod 74 carries the rod 76 by two arms 75, 75a, and during the rotation of the shaft 10, the arm 70, Fig. 5, which is mounted on an eccentric on the shaft, pulls down the frame formed by the rods 74, 76. In the case of a lever 62 which has not been selected, the corresponding lever 81 moves about the rod 74 as centre; but for a selected lever 62, the corresponding lever 81 moves to the position shown in dotted lines in Fig. 2, thus raising the typewriter lever 71 to print the letter. The spring levers 81 for letterprinting are made less elastic than the levers 81<a> ... 81<e> provided for performing other operations. Change of case, Fig. 6. The lever 62<a> is provided for making a change of case. This lever is opposite a row of notches in the bars when they are in their normal positions, but the notches have bevelled edges, so that the movement of any bar pushes out the lever 62<a>. When the magnet 38 is energized without any bar B having been moved, the corresponding lever 81<a> depresses the change of case key 71<a>, and this key is held down by the pawl 83<a> engaging with the nose 78<b> of the lever 78. The pawl 82 in this case moves to the left-hand position shown in dotted lines, but when another lever 62 is selected to print a letter, the lever 81<a> is not engaged by the lever 62<a>, and the pawl 82 moves to the right-hand position shown in dotted lines; during the return movement, after the letter has been printed, the pawl 82 engages with the lip 80 on the lever 78 and releases the key 71<a>. Line-spacing, Figs. 1, 7, and 8. The selection of the lever 62b causes the lever 81<b> to operate the line-spacing lever 71<b>. In order that the messages may be printed on sheets of paper of uniform size, each message should be started a definite number of lines from the first line of the preceding message. To provide for this, each action of the lever 81<b> is arranged to rotate the ratchet-wheel 91 a step by means of the lever 87<b>. Further, the lever 62<b> is made in two parts 85, 62<b> pivoted together. At the end of a message, the lever 62<c> is selected. The effect of this is to cause a lever 87<c> to depress a rod 94, which, through its connexion with the lever 93, causes the lever 62b to buckle at its pivot point 85<a>. The lever 62<b> is held in this position by the pawl arm 96 engaging with the arm 93<a>, which is mounted with the lever 93. The depression of the lever 93 also rotates the shaft 95, Fig. 8, and the arm 95<a> on this shaft depresses the lever 54 through the lever 97. The effect of this is to operate the clutch 45, 51, and the shaft 10 rotates continuously. At each rotation, the arm 81<b> is depressed, and hence the paper is fed forward a line and the ratchet-wheel 91 moves a step. When the pin 98 on the ratchet-wheel reaches the arm 96, the lever 93 is released, the lever 62<b> returns to its normal position, and the line-spacing ceases. Carriage-return mechanism, Figs. 1 and 7. When the level 62<d> is selected, the arm 87<d> depresses the rod 94<a>, thus removing the pawl 109, Fig. 1, from the spring-pressed arm 108 and allowing the yoke 107 to close the clutch 105, 106. The effect of this is to enable the shaft 6 to drive the wheel 115 through the gear-wheels 106<b>, 112, 113. The gear 115 is mounted on the shaft 116, which rotates the drum 117 to return the carriage C. When the carriage has returned, the projection 119 disengages the clutch. The drum 117 is connected to the shaft 116 by a friction clutch, which comprises two plates 101 of spring steel mounted on a hub 102 and two rings 103 of fibre between the plates and the drum. Signalling to operator. The bell clapper 121, Fig. 1, is actuated by selecting the lever 62<c>.