Patent GB-773285-A (GB)
Title: Data comparing device
Filed: 1955-08-26
Abstract: 773,285. Statistical apparatus. INTERNATIONAL BUSINESS MACHINES CORPORATION. Aug. 26, 1955 [Aug. 31, 1954], No. 24558/55. Class 106 (1). A data comparing device for determining the relative magnitude of a primary data with respect to a secondary data, each of the data being arranged according to a first prescribed scale and within one of a plurality of classes, each of the classes being arranged according to a second prescribed scale, comprises first means for comparing the primary and secondary data so as to determine their relative magnitudes in accordance with the first prescribed scale, and second comparing means effective consequent upon an unequal determination by the first means to modify the determination in accordance with the second scale. On the record cards used, the data is represented in each column by one or more perforations according to the code shown in Fig. 3 (the first scale). Each column has twelve index positions R, X, 0, 1, 2-9. Numerical information is represented by a single perforation in a corresponding index position, alphabetical information is represented by one entry in a zone position (R, X or 0) and one entry in a numerical position and special-character information is represented by a single entry in a zone position or by a combination of entries in zone and numerical positions. Further there is blank column information which is designated by the absence of any entry. Cards punched according to this code are not readily collatable since the characters defined do not fall into a sequence of groups which may be arbitrarily selected as below:- This is the second scale referred to above. When it is desired to determine the relative magnitude of a first data with respect to a second data it is necessary to correct or modify by a suitable means the comparison initially produced according to the first scale (Fig. 3) so as to produce a final relative magnitude result which is in accordance with the prescribed scale of values (i.e. the second scale). If the first comparison indicates equal data the second comparison is unnecessary, but if they are not equal the correction must be made to give a final relative magnitude result. The invention may be applied to a card collator, e.g. similar to that described in Specification 523,652. Cards are fed from primary and secondary card hoppers along converging paths towards collecting pockets. Sensing brushes positioned at points along the paths read the cards as they pass. Two sets of brushes are provided for the primary cards, at primary brush station (PBS) and a sequence brush station (QBS). One set of brushes is provided for the secondary cards, at a secondary brush station (SBS). The sequence brushes are for comparing cards moving in sequence from the primary hopper. Such comparisons are made in exactly the same way, when required, as comparisons between primary and secondary card date. As shown in Fig. 2, the sensing brushes are connected to code relays (blocks 51, 52, 53) which are picked in accordance with the binary code shown in Fig. 3. The primary station code relays within block 52 and the secondary station code relays within block 53 govern contacts arranged in a circuit to form a primary-secondary data compare unit represented by block 55. Block 54 similarly represents a sequence data compare unit. The correction relays within block 61 correct or modify an initial comparing result so that the final result is in accordance with the prescribed scale of values. The outputs from compare units 54, 55 are used to govern control relays within blocks 56, 57 which set up contacts in blocks 58 to control primary, secondary and eject clutches (block 59) and the record card distributing magnets (block 60). The twelve position card indicia code (Fig. 3) is translated to an intermediate six position binary code (see Fig. 3) and six relays, A to F, are accordingly provided responsive to signals sensed by the brushes. The relays are picked as indicated in the binary code column, Fig. 3, and their contacts are arranged to form the compare circuits represented by blocks 54, 55. Further contacts of the code relays are arranged to form a circuit for detecting whether the character sensed is a special character. Such a circuit is provided for primary, secondary and sequence brush stations. There are also provided for each brush a station circuit to determine whether the column sensed on the card is blank. If the first comparison indicates that the primary data is of greater magnitude than the secondary data, it is necessary to determine whether the primary data is within the special class and if it is, the primary data should be low according to the second scale. The primary special character circuit accordingly directs the test impulse to the secondary special character circuit to determine whether the secondary data is also a special character. If it is the initial comparing result will be correct because the two data are in the same class. If the primary data is blank the primary blank correction circuits will alter the initial comparing result. If, conversely, the primary data is of smaller magnitude than the secondary data it is necessary to determine whether the primary data fall within the special character class and if it does the initial comparison will be correct in accordance with the second scale. If the primary data is not a special character it must be determined whether the secondary data is, and if so the initial comparing result is altered. If the secondary data is in the blank class the initial comparing result will again be altered. Circuits are shown and described with reference to examples.