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United States Patent 0

1

3,512,139 SYSTEM AND APPARATUS FOR AUTOMATIC

DATA COLLECTION Andrew C. Reynolds, Jr., Waterbury, John F. Carragan, Woodbury, and George J. Yagusic, Watertown, Conn., assignors, by mesne assignments, to Control Data Corporation, Minneapolis, Minn., a corporation of Minnesota

Filed Dec. 31, 1959, Ser. No. 863,227 Int. Cl. Gllb 13/00; G06f 1/00, 7/00

US. Cl. 340—172.5 37 Claims

This invention relates to a system for automatic data communication and collection, and a central receiver recorder for such a system. More particularly, the inven tion relates to an on line, or real time, system for use in collecting, sorting, collating, and transmitting data from a plurality of remote station transmitters to a cen tral o?ice receiver and recorder. The automatic communication system of the present

invention may be used, for example, in factories where a plurality of data transmitters may be installed in dif ferent areas, shops, or departments, for transmission of manufacturing data to the central receiver-recorder of the invention ‘which may be located in a central accounting o?ice. Such data may include: numbers of units manu factured on particular machines; designated job orders ?lled by machine operators; identity and hourly wage rates of the machine operators; total time required for each operation, etc. Alternatively, the apparatus of the inven tion may be used in warehouses and distribution centers for collection of order receipt and delivery time informa tion for inventory control purposes, or in department stores for automatic collection of point of origin sales data, etc.

In a large factory, for example, there is at present a great deal of paper work required to be done in the vari ous shops and departments, including such handwritten reports as time tickets for payroll entries, production and inventory control records, cost accounting, quality con trol inspection and scheduling reports, etc. For automatic ce'ntral office computing, this mass of data now has to be individually punched into cards by manual operations, and the punched cards have to be veri?ed by human op erators before they can be fed to tabulating or computer apparatus. Various systems which have heretofore been suggested for expediting the How of this information into the central o?ice have included the use of closed circuit television, which introduces the added problem of hu man error in reading the data from the TV screen, and the use of intercommunicating telephone circuits, which frequently results in error and misunderstanding of the verbally-relayed information. In these prior art systems, the multiplicity of personnel involved results in divided responsibility, which is quite undesirable. The principle of the data transmission and collection

system of the present invention is to capture the required information at the point of origin, select, sort, and col late it automatically and substantially instantaneously, and then to transmit infallibly the desired data to a cen tral receiver-recorder where it is permanently punched into tape or recorded on some other common language medium which can be fed directly into an automatic computer without the further intervention of possible human error.

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3,512,139 Patented May 12, 1970 'ice

2 In the copending application of A. C. Reynolds, Jr.,

et al., Ser. No. 841,926 ?led Sept. 21, 1959, and entitled “Data Transmission Apparatus” which is assigned to the same assignee as the present application, there is disclosed the apparatus and circuitry of a data transmitter for the system of the present invention, including data card han dling and reading apparatus, apparatus for encoding ?xed and variable input information, and scanner and control circuits for such apparatus. The present application dis— closes some controls of the data transmitter of the pres ent invention not shown in the above-identi?ed applica tion, which controls are used for intercommunication be tween the central receiver-recorder and the data transmit ters in the system of the invention. This application also discloses and claims a preferred embodiment of a cen tral receiver-recorder for the system of the invention. An important feature of the invention is the transmis

sion of information set into the data transmitters at any time in the form of a plurality of data cards, manually adjustable dials, and automatic telemetry signals over a plurality of data transmission channels equal in number to the number of code channels on the data cards. Another feature of the invention is the initiation of

transmission, selection and operation of a ready transmit ter by means of a multiple conductor, coded search line system, using fewer search conductors than there are numbers of transmitters in the system. A further feature of the invention is provision for the

location and selection of another transmitter, which is ready to transmit during the progress of recording a transmission from a previously selected transmitter, there by eliminating switching delays at the central office. Another feature is the translation of the data received

at the central receiver-recorder into a different code for a continuous recording medium, illustratively record tape, having either a greater or lesser number of channels than the data cards, and including a parity check channel.

Still another feature of the invention is the generation at the central receiver-recorder of space symbols to be recorded on the continuous medium when ?elds contain ing no symbols occur in a message. A further feature is the provision of a synchronous shift

register or buffer storage unit which synchronizes the incoming data characters to the recording rate of the con tinuous medium recorder. A still further feature of the invention is a novel low

voltage monitoring circuit which insures that no data will be lost during periods of ?uctuating line voltage.

Still another feature of the invention is the continuous automatic resetting of all bistable elements of the re ceiver-recorder during periods when no message is being received. A further feature of the invention is the provision at

the central receiver-recorder for recording a central of?ce message including instantaneous time, date, and addi tional preselected characters which may be recorded on the continuous medium either prior to or subsequently to recording of the received transmitter messages. A still further important feature of the invention is

the automatic transmission from the remote transmitters of a number corresponding to the total number of char actors in each message being transmitted, and apparatus at the central receiver-recorder for comparing this num ber with the number of characters actually received.

3,512,139 Other features of the invention will ‘become apparent

from consideration of the following speci?cation. In the art of machine data handling and data process

ing, commonly referred to as automatic computing, one of the most serious problems has long been to ?nd rapid and accurate means for feeding input information into the available high speed data processing equipment. While known types of electronic computers are capable of op erating upon great quantities of data very rapidly, and can solve complex problems and record accurate answers very quickly, much time and human effort is required to assemble, sort, collate, compile, and insert the input data which is the information that the big computers are adapted to operate upon. The lab-or of skilled and semi skilled persons, who may be engaged for many hours or days in preparing the required input data, is not only costly and susceptible of human error but by the time in put media is prepared for the computer the usefulness of the data may be lost or greatly impaired.

It is to these problems of facilitating, expediting, and economizing on the input of statistical data into auto matic data processing systems, and to assuring greater ac curacy of such information, that the present invention is broadly directed.

In the applications of Curtis Hillyer, Ser. No. 556,120 ?led Dec. 29, 1955 entitled “Automatic Information Transmission" and Ser. No. 686,070 ?led Sept. 25, 1957 entitled “Data Transmission Apparatus,” ‘which applica tions are assigned to the same assignee as the present in vention, there is disclosed a system and apparatus for automatic information transmission and collecting com prising a plurality of data transmitters connected to a cen tral receiver-recorder. The system of the present inven tion is an improvement in the system disclosed in the above-identified Hillyer applications.

In order to manufacture a commercially acceptable au tomatic data collection system, many problems must be solved. For example, the message recorded at the central receiver-recorder must be extremely accurate and error free since the recording is made on a continuous medium which is adapted to be directly fed into a computer with out the intervention of further veri?cation. On the other hand, it is important that the message be transmitted to the central receiver-recorder in a very short period of time so that other transmitters connected to the central receiver-recorder which are ready to transmit their mes sage will not have to wait very long, thus various com monly known forms of redundant transmission of infor mation cannot be used. The cable that connects the data transmitters to the cen

tral receiver-recorder must have a minimum number of conductors to transmit the information and to transmit various control signals, yet reduction of the number of conductors must not unduly increase the complexity of the data transmitters or the central receiver-recorder. In particular, since a plurality of data transmitters will ordinarily be connected to a single central receiver-re corder, in order to insure minimum system cost the data transmitters must be kept as simple as possible.

Since a data transmitter, in a properly designated sys tem, may be much less complex and costly than a central receiver-recorder, it becomes important to maximize the number of transmitters which may be connected to one receiver-recorder. This means that the time required for transmission and the necessary interval between messages must be reduced to a minimum. When this is done addi tional transmitters may be connected to a single central receiver-recorder without increasing the waiting time for a ready transmitter during peak loading periods. Further more, the connection of each transmitter to the cable should be kept as simple as possible. Ideally the system should be completely parallel, and therefore each trans mitter should be effectively connected to each conductor of the cable. The common cable used in the system of the present

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4 invention will necessarily be in proximity to electrical noise generators, for example, heavy electrical machinery in factories. The system must, therefore, have a very high degree of discrimination between random interference noise signals and the information signals being trans mitted from the data transmitters. As previously stated, since time is of the essence in the system, various forms of redundant transmission in time cannot be used. Other means had to be found which would assure that the cen tral receiver-recorder be free from various transient and noise signals on the data transmission lines.

In order to minimize further the number of conductors required in the common cable, it is desirable that all in formation transmitted to the central receiver-recorder from the remote data transmitters be transmitted in a common language that is in one particular code. Thus the information from data cards, variable dials, telemeter ing inputs, special characters, etc., should all arrive at the central receiver-recorder in the same code; yet this form of transmission must not unduly complicate the apparatus at the data transmitters. Any translation from one code to another should therefore take place at the central re ceiver-recorder. As discussed in the above identi?ed application of

Andrew Craig Reynolds, Jr., et al., the simplest method of achieving this objective is to transmit all the data from each data transmitter in the code of the data cards. Means must then be provided at the central receiver-recorder for translating this code into the common language code adapted for recording on the continuous medium chosen as the output of the central receiver-recorder.

Also, since in the present state of the art it is possible to provide continuous medium recorders having much higher clock rates (at which characters may be recorded) than the rate at which characters may be transmitted from the data transmitters; and since available continuous medium recorders are generally demand devices, that is, they re quest a character when they are ready to record a char acter; the incoming characters from the data transmitters of the invention are temporarily stored in a buffer stor age and synchronized with the clock rate of the continu ous medium recorder prior to their being recorded. A buf fer storage unit for this purpose accepts characters as they are received from the data transmitters and supplies characters for recording to the continuous recorder upon request. Furthermore, since the rate at which characters are transmitted from the data transmitters may vary from the normal average rate, due to variations in line voltage at the data transmitters, or differences in hole spacing and hole size on the data cards, the buffer storage unit of the invention must be able to store enough characters prior to recording so that no characters are lost, and yet it is desirable that the storage means he of minimum size in order to minimize cost. A central receiver-recorder for an automatic data col

lection system of this nature must, for some users thereof, be able to supply characters for recording on the con tinuous medium in the absence of received characters from the data transmitters. That is, for example, many of the users of such a data system will not wish to punch a character on their data cards between ?elds of data characters which they wish to have recorded on the con tinuous medium with space characters inserted there between. In this case, the central receiver-recorder must be adapted to provide the proper number of space char acters for the continuous medium recorder between re~ ceipt of the data characters as read from the data cards. As the rate of transmission from the data transmitters varies, the central receiver-recorder must be able to rec ognize the early or late receipt of a data character so that no space character will be improperly recorded by the continuous medium recorder.

Since many computing machines using the continuous medium records produced by central receiver'recorders are provided with a parity monitoring means for detect~