GB392356A - Number indicating arrangements for the impulse transmitters of automatic telephone instruments - Google Patents

Abstract

392,356. Impulse transmitters. GREENBERG, W., 269, North 26th Street, Por'tland, Oregon, U.S.A. May 7, 1932, No. 13266. [Class 40 (iv).] An indicator for showing the number dialled is, associated with an impulse transmitter, the indicator being set by bars successively cooperating with a cam surface formed on the inside of the casing and setting the indicator drums through rack and pinion gearing. When the first digit of the number is dialled the end of the first bar 36 slides along the cam surface 7, formed on the inside of the casing 6, and moves the first indicator drum, through rack 28 and pinion 21, to display the relative indication. As the dial restores pawl 62 engages one of the teeth 23 and holds the indicator whilst the bar 36 drops into the lower slot 59 in the guide block 27 (see Fig. 5), to bring its end out of the range of the cam surface. The pawl 50 engages the first tooth on the ratchet selector 42 and allows the second bar 37 to fall into the path of the cam 7. This bar 37 is now moved in accordance with the second digit and sets the second indicator drum to display the second digit. On the return movement of the dial this bar 37 falls below the cam surface and 42 is' moved another step to bring bar 38 into operative position, the cycle being repeated for each digit dialled. To reset the mechanism the button 66 is depressed so that, by means of the linkage shown, the bars 25 are all raised above the selector ratchet 42, the holding dog 49 is disengaged from the teeth on selector' 42 to let the latter return to its normal position beneath the bars 25 and the holding pawls 62 are removed from teeth 23 to allow the indicator drums and operating bars to resume their original positions.