Patent GB-529047-A (GB)
Title: Improvements in automatic switches for use in telephone or like systems
IPC: H01H67/12
Filed: 1939-05-09
Abstract: 529,047. Automatic exchange switches. ASSOCIATED ELECTRIC LABORATORIES, Inc. May 9, 1939, No. 13880. Convention date, June 20, 1938. [Class 40 (iv)] A switching unit comprises a number of independently movable elementary switches one of which is selected in accordance with the first digit whereupon a carriage portion thereof is moved in response to the second digit and a wiper carrying portion is moved in a direction at right angles in response to the third digit. All the elementary switches are controlled by common operating mechanism. As shown, each of the ten wiper-units comprises a carriage 36 which is mounted on longitudinal guide bars 42, 43 and which carries a movable slide 37 on which the wipers are mounted. An operating shaft 48 carries ten coupling members 50, and the rotation of the shaft couples a selected carriage thereto by the engagement of a  projection 50a in a corresponding slot, so that the carriage then follows the longitudinal movement of the shaft. The wipers are then moved into the multiple by the rotation of an operating shaft 58 by the engagement of a toothed flange on the slide 37 with a correspinding ratchet 61 on the shaft. During this movement, the flange engages one of ten notches in a locking bar 37a. All the three movements are effected in a step-by-step manner by a magnet 69 which operates a ratchet wheel 75, and the sequence control is is effected by a magnet 100 which operates a ratchet wheel 93 integral with a pair of cams 94, 95. The cam 94 controls through a lever 106 a clutch which couples the ratchet wheel 75 alternately with the shaft 58 and through spiral gearing 91, 92 with the shaft 48, while the cam 95 controls a locking bar 117 which alternately permits rotation and longitudinal movement of the shaft 48. In operation, the first series of impulses received by the magnet. 69 rotates the shaft 48 to select a carriage 36. The magnet 100 then operates to lock the shaft 48 against rotation, the bar 117 engaging a notched disc 118, and to permit its longitudinal movement by withdrawal of a locking arm 121. The magnet 69 then effects the longitudinal movement through the spiral gearing 91, 92. The next operation of the magnet 100 clutches the shaft 58 to the ratchet wheel 75, so that the magnet 69 moves the slide of the selected carriage into the multiple. A third operation of the magnet 100 releases the locking bar 117, so that the spring 85 operates through the spiral gearing 91, 92 to move the bar 48 first rotarily and then longitudinally back to normal, the detent 54 engaging the ratchet 53 having been withdrawn by the rotation of the shaft 58. To restore the selector to normal, the magnet 100 operates again to declutch the shaft 58 from the ratchet wheel 75, so that it rotates to normal under the control of a spring 68. The selector units are mounted one above the other on both sides of the multiple 24 with vertical staggering. The base plate of each unit is supported on ledges and is secured to the side frames by screws engaging in slots to allow adjustment in a longitudinal direction. A pair of screws permit adjustment to and from the multiple.