Patent GB-191304792-A (GB)
Title: Improvements in or relating to Impulse Transmitters for Automatic Telephone Plant.
Inventor: BETULANDER GOTTHILF ANSGARIUS
IPC: H04M1/272
Filed: 1913-02-25
Granted: 1913-09-25
Abstract: 4792. Betulander, G. A. Feb. 28, 1912, [Convention date]. Impulse-transmitters for automatic telephone systems. The number required is set up by a number of pointers or the like operating impulsedisks, each with its own spring-return device, which devices are released in succession when the telephone receiver is lifted, the pointers and impulse-disks being returnable from an advanced position while the return device remains locked, for correcting a wrong setting, and each pointer remaining in its advanced position until the corresponding impulse-mechanism has operated. When the apparatus is in its normal position, with the receiver in the cradle mounted on the rod 62, Fig. 4, the rod is depressed and rocks the lever 63 and arm 37 about its pivot, so that the hook 24 on the disk 17 of the first setting-pointer engages the corresponding impulse-disk 26. This pointer is now moved to the required position, to the right in Fig. 4 and the left in Fig. 8, carrying with it the impulse-disk 26 and also, by means of the pin 29, the cam disk 27, which is attached to a disk 11 by a sleeve 13, Fig. 10, on which the disks 17, 26 can rotate and which encloses a spring 14 connecting it to the boss 9 on the support 8. The disks 17, 11 are held in their adjusted positions by the pawls 19, 31 respectively engaging teeth in them; if now the pointer has been moved too far, it can be moved back, carrying the impulse-disk 26 with it, the disks 11, 27 remaining advanced. In the meantime, the pin 29 of the first impulse-mechanism has moved from the cam 39 of the arm 37 of the second mechanism, so engaging the hook 24 of this mechanism with its disk 26, and this pointer is now set similarly to the first. In a similar manner, all the pointers are set in turn, the pointers 16 flying back when released if it is attempted to set them in the wrong order. To start the mechanism, the reservoir is removed, whereby the pin 74, Fig. 4, disengages the pawl 31 of the first impulse-mechanism, which is returned to zero by the spring 14, the pawls 42, 43 driving the disk 4 fast to the shaft 3, which is retarded by a friction governor. During this return, the teeth of the impulse disk 26 act on the hook 53 to rock the shaft 52 to send the impulses by earthing both lines, the shaft being held out of action by the hook 53 of the last impulse-disk resting on a cam-part 49 till this disk has been set. The hook 24 of the first mechanism having been disengaged by its arm 37, the pointer 16 remains locked till the impulse-disk reaches its rest position, whereupon a cam-surface on it disengages the pawl 19; at the same time, the cam 30 disengages the pawl 31 of the second impulse-mechanism and the pin 29 rocks the arm 37 of this mechanism to disengage its hook 24. In this way all the mechanisms are released in turn. While the receiver is in the cradle, the speed-governor is locked, means being provided to prevent the replacement of the receiver during the operation of the mechanism from actuating this lock. Contact springs are arranged to be operated by the weight of the receiver for changing the circuits of the bell and telephone, and for closing one of the line circuits momentarily when the receiver is replaced but not when removed.