Patent GB-191119661-A (GB)
Title: Improvements in Impulse Transmitters for Automatic Exchange Telephone Systems.
Inventor: BETULANDER GOTTHILF ANSGARIUS
IPC: H04M1/274
Filed: 1911-09-04
Granted: 1912-03-14
Abstract: 19,661. Betulander, G. A. Sept. 5, 1910, [Convention date]. Automatic exchange systems; telephones, mounting and supporting.-In an impulse transmitter for automatic exchange telephone systems in which the number of the wanted subscriber is first set by separate pointers, &c., for each digit, the winding of the spring, which subsequently operates the contact-maker, is effected by the act of setting one or more of the pointers. The invention is described as applied to an impulse transmitter for four-digit numbers, in which the operation of the thousands digit pointer winds up a spring, which is released when the micro-telephone is removed from its cradle, whereupon the contact member 53, Fig. 7, rotates over four sets of contacts 58, Figs. 3, 7, some of which have been earthed by the setting of the digit pointers. The four circular contact disks 4, Figs. 3, 4, each provided with a setting- lever 5, are loosely mounted on a shaft 3, and are formed with an insulated part 10, Fig. 4, which normally engages a set of ten contacts 9, connected to the corresponding set of contacts 58, Fig. 7, in the path of the member 53. The rotation of the setting levers 5 brings the metal part of the disks 4 into engagement with one or more contacts 9, thus earthing one or more of the contacts 58. The con'act member 53 is fixed to a shaft 23, connected by a spiral spring 39 to a disk 29, which is loose on the shaft 23 and carries a pawl 32, Fig. 3, which engages a notch in a disk 28, secured to a pinion 24 engaging a toothed segment 22 fixed to the shaft 3. The rotation of the thousands digit setting-lever 5 causes its pawl 12, Fig. 4, to rotate a disk 11 secured to the shaft 3, thereby causing the disk 28 to rotate the disk 29 through rather more than a revolution, so as to tension the spring 39. The contact member 53 is prevented from rotating at this stage by a rod 77, Fig. 4, controlled by the telephone cradle. When the pawl 12 has rotated the disks 28, 29 fully, it engages a cam 16 on a fixed disk 15, and is raised from the disk 11, which is now held by its notch 18 engaging a catch 17 controlled by the telephone cradle. When the telephone is removed, the rod 77 frees the member 53, which is rotated by the spring 39 through a complete revolution, the contact roller 57 engaging a continuous wire 59, whilst the roller 56 sends impulses to line as it passes over those contacts 58 which are earthed. When, at the end of a conversation, the telephone is replaced, the catch 17 releases the disk 11, which is returned to its normal position by the springs 19, Fig. 3, on the ends of the shaft 3. To retard the rotation of the member 53, the shaft 23 is connected to a vane 50 through gears 36, 44, 47, and 48. The setting-levers 5 are retained in their set position against the action of springs 84 by means' of holes 83 which engage pins 82 on levers 81, carrying rollers 93. A pivoted yoke 85, Figs. 3, 4, supports arms 91 which carry conical pins 92, in such a manner that the levers 81 are pressed apart to release the levers 5 when the yoke 85 is depressed by a roller 90 on the segment 22 of the thousands setting-lever. Any attempt to set the other pointers before setting the thousands pointer, which winds the operating-spring, is thus unsuccessful, as the levers are at once drawn back by their springs 84.