GB409374A - Improvements in or relating to record-controlled statistical printing machines - Google Patents

Abstract

409,374. Statistical machines. BRITISH TABULATING MACHINE CO., Ltd., Victoria House, Vernon Place, Southampton Row, London. Oct. 31, 1932, No. 30594. Convention date, Dec. 24, 1931. [Class 106 (i).] The invention relates to record - controlled statistical printing machines of the kind in which the perforated records are read in motion and in which type carriers are reciprocated past a printing line in synchronism with the card reading and are arrested when card holes are read so that the appropriate type is positioned at the printing-line ; the typecarriers being subsequently restored. In a machine of this type and in which the reading occupies the major portion (e.g. 10/14ths) of the machine cycle, the invention consists in providing gearing whereby some or all of the mechanisms of the machine are driven at a constant velocity during the card reading portion of the cycle and at a decreasing and then increasing velocity during the rest of the machine cycle. The object is to increase the speed of the card reading and the type-carrier setting without increasing the speed of restoration of the type-carriers. In known machines these carriers are set at one rate and returned at a faster rate. In the present invention the type-carriers are moved at substantially the same speed in each direction. The invention is applied to the kind of machine described in Specification 247,200, [Class 106 (i)], having vertically reciprocated type bars which are arrested differentially by electromagnetically released pawls when the holes are read. The type bars are reciprocated by a groove 23, in a cam 21 which rotates once per card cycle, which groove is so designed that the bars are raised during half a card cycle and then lowered during the second half cycle. The bars being thus raised during ¢, instead of 10 /14ths, of a card cycle, the card feed mechanism 33, 34, 36, 40, 41, 42 is driven faster by non-circular gear wheels 51, 52, actuated through the train 44, 48, 47, 46, 45 from the machine motor, whereby the cards are read at a fast though steady speed. The wheels 51, 52 have the same number of teeth and half of the wheel 52 (in angular measurement) is circular, whereas 10/14ths of the wheel 51 is circular. The reading mechanism will thus complete 10/14ths of its complete cycle whilst the printing mechanism, driven through train 52, 49, 50, 22, 21, 23, completes of its cycle. During the remainder of the cycle the card feed first slows down and then accelerates so as to complete a full cycle in the same time as the full cycle of the printing mechanism. It is possible to drive the printing mechanism through the gears 51, 52, or similar gearing, but the above arrangement is preferred.