Patent GB-906296-A (GB)
Title: Automatic character reading apparatus
Filed: 1959-10-02
Abstract: 906,296. Automatic character reading. CUMMINS-CHICAGO CORPORATION. Oct. 2, 1959 [Oct. 20, 1958], No. 33442/59. Class 106 (1). Characters legibly represented on a record such as a cheque. Fig. 1, as patterns of perforations at positions within a 3 Î 6 matrix are sensed by elements located at predetermined ones of these positions and electric signals derived from the sensing are converted to a single signal representing the character sensed. The upper zone of the cheque, Fig. 1, carries punched characters, the lower zone carries the usual written and printed information. Between the two zones is a row of feed holes 25 by which the cheque is located as it is fed through the machine as described below. The feed holes have the same spacing as the recorded characters. The four positions of the matrix which are sensed are shown in Fig. 3. In addition a fifth position, the seventh row in the third column is provided for a parity check hole c which is added in order that the total number of holes sensed shall always be even. The representations of digits 1-9 and 0 and symbols "+" and "-" are shown in Fig. 2. Data common to a number of cheques e.g. the numbers 21 and 22 may be applied by punching through a number of cheques at once. Cheque feeding.-The cheques are fed singly from a stack 30, Fig. 4, by a friction roll 35 and are taken by a band 36, against which they are pressed by balls, to a pin drum 39. The leading edge of the cheque engages a fixed finger 40 which holds up the cheque until the first hole fits over one of the pins. The cheque is then drawn round an arc of the drum by the pins being held in close engagement with it by a spring-tensioned band 42. On leaving the drum the cheque is taken by another friction band 44 and delivered to an output hopper. Sensing.-During its passage round the drum 39 the cheque is also guided by an idler drum 49, Fig. 6, there being a space between the two drums so that light from a lamp 50 can fall on to the perforated zone of the cheque. Light passing through the holes of the character representations falls on to a mask 48a, Fig. 5, having openings at the sensing positions shown in Fig. 3 which lead to photocells in the sensing head. Two other openings are provided leading to photo-cells PCD, PCE which detect the presence or absence of a cheque at the sensing position. Timing pulses for gating out the signals from the photo-cells at the instant when a character pattern is properly aligned with the mask 48a are derived from holes 39c in the side wall of the drum, through which light passes to a photo-cell PCS. Recognition circuit, Fig. 7.-The outputs from each of the matrix position photo-cells PC6, PC8, PC10, PC15 and PCc are amplified and clipped to a uniform value before application to gates G6, G8, G10, G15 and Gc. The other input to these gates is from the timing pulse photo-cell PCS but a gate 90 in this circuit prevents the gates G6 &c. being opened when there is no cheque at the sensing station. For this purpose the signal from photo-cell PCD is inverted and used to control the gate so that the gate opens only when there is no signal from the photo-cell owing to its being obscured by a cheque. The gating pulse from gate 90 is delayed in an adjustable delay 92 before application to gates G6 &c. For the purpose of setting this delay so that the read out pulse synchronizes exactly with the appearance of character signals the read out pulse is applied to a cathode-ray tube 275 together with the signal from one of the photo-cells which may be selected by a switch 279. The trace on the screen indicates exactly the time relationship of the signals and the delay is adjusted accordingly. The gates G6, G8, G10, G15 and Gc give positive and negative outputs on paired leads 170, 174 when the corresponding photo-cells give signals at the instant of the gating pulse. These leads are connected by diodes in a matrix 210 to vertical output leads connected to terminals 1-9, 0, + an -. According to the combination of input signals from the five photo-cells, a positive output from B+ appears on one of these terminals. The " end-of-cheque " photo cell PCE gives a signal as soon as the cheque clears the sensing station. This signal after amplification, clipping inverting and differentiation appears on terminal E and indicates to the apparatus (e.g. statistical apparatus or a sorter) that one cheque is completely read and that subsequent data belongs to a following cheque.