SU696443A1 - Device for retrieval of punched cards - Google Patents

Description

(54) DEVICE TO SEARCH PUNCH CARDS

The invention relates to the field of electrical computer technology, namely, to information retrieval tools and can be used5

in mechanized and automated information retrieval systems.

There are known devices for sorting and searching for punched cards that contain a reading unit, the output j of the OToporo soe-y Yudinen with the first input of the comparator, the second input of which is connected to the output of the switching unit, the input of which is connected to the second output of the position selector of the punched card punch cards whose input through the control unit is connected to the output of the memory unit, the first input of which is connected to the outputs of the comparing unit, the task block for logical operations, 20

the output of which is connected to the third input of the comparison unit 1.

A disadvantage of the known devices is the impossibility of specifying logical operations on the features, which by 25 are searched for punched cards, in order to soften the selection criteria.

The purpose of the present invention is to improve the speed of the device by performing a search in one run for any number of features.

This is achieved by the fact that the second output of the logic operation task block is connected to the second input of the memory unit, and the first input of the position selection unit is connected to the second input of the control unit.

The drawing shows a block diagram of a device for searching punched cards. The device comprises a reading unit 1, a comparison unit 2, a switching unit 3, a block card position selection unit 4, a memory unit 5, a control unit 6, a punched card supply unit 7, a logical operations task unit 8. The information outputs of the readout unit 1, which is a photovoltaic unit for positional reading of information printed on a punched card, are connected by an eight-channel line with the first inputs of the comparator unit 2, which is a collection of 80 groups of three inverting riEs each. The second inputs of the comparison unit 2 are connected to the outputs of the switching unit 3, which is

a set of bipolar switching elements (switches) with a matrix of decoupling diodes arranged in the form of an information floor of a punched card. The second output of the position selection unit 4, represented by an electromechanical current distributor, is connected to the input of the switching unit 3, and the first to the second input of the control block b. The first output of block 8 of the task of logical operations is connected to the third input of block 2 of the comparison, the second output of block 8 is connected to the second input of block 5. Output of comparison unit 2 through memory block 5 and block

6 control connected to block input

7 punch cards.

The device works as follows 3 ohm.

An array of punched cards with information (features) applied to them is put into the device’s pocket, and in the switching unit 3, the dialing (by switching to the operating state of the switching elements) information is collected. I) corresponding to the sampling program, i.e. on which comparison and selection of punched cards will be made. In the task block for logical operations 3s1, the necessary logical operations (AND, OR, NOT) on the signs are given; the corresponding inputs of block 2 are switched. comparison and memory block 5. After starting the device, the information printed on the punch card is positionally read in read block 1 and the information signals corresponding to the punched holes in this position of the punch card go to the first inputs of the inverters NOT of the compare unit f 2 to its second input position through the corresponding groups of switching elements of the switching unit 3. Simultaneously with the reading of this position of the punch card in the position selection unit 4, a strobe signal is generated, arriving through the switching unit 3 to the second input of block 2, a comparison,

When, for example, a logical operation I is specified, these two signals — read from the punch card and gating — are compared for a match to two successively switched on schemes — NOT, forming the prohibition element. Such an inclusion provides a discrepancy detection, t. e. logical operation AND on given signs; punched cards that have all the given attributes will be selected. Comparing the information read from this position of the punch card with the information typed in the switching unit 3 under the effect of the strobe signal at the output of the comparison unit 2 in the case of a discrepancy between the read and typed information, a signal is generated that arrives at the first input of the unit 5 and includes elements that fix mismatch. At the end of the process of reading all positions of the punched card in block 4, the position of the end of the punched card is generated at the second input of control unit 6, the signal of the memory element fixing the mismatch is sent to its first input, and the mechanism for moving the punched card is not activated, i.e. The punched card is guided into the general receiving pocket of the device.

In the event that in the process of positional reading of a punched card, the information printed on the punched card and typed in the switching unit 3 completely coincides (i.e., no mismatch occurs) the memory element fixing the inconsistency remains in its original state, and the signal the end of the punch card includes a mechanism for moving it into the selection pocket. When specifying a logical operation OR Above the specified indicia, two consecutively connected circuit boards of the comparison unit 2 are connected, additionally, to their second input, the element riE by switching in block 8 of the task, logical operations. With such elements turned on, the output signal is generated only if the information read from the punch card coincides with the information typed in the switching unit. In case of coincidence of one of the signs, when reading under the influence of a strobe signal at the output of comparison unit 2, a signal is generated that includes the memory element of block 5, which fixes the coincidence. The further selection process proceeds as in the case of the absence of mismatches during the implementation of operation AND

in case of a discrepancy between one of the signs read from the punch card and the one specified in the switching unit 3, the punch card will also be selected. Only punched cards that do not contain any of the specified features will not be selected. This implements the OR operation. (

When specifying a logical NOT operation (negation) of a sign, the memory element of the punched card sampling unit records every occurrence of a given sign in the process of reading. The output signal of the readout unit in this case goes through the He circuit of the comparison unit 2 and fixes; with memory element. After the end of the readout process in block 6, the control