US2776091A - Electrical apparatus for computing a check symbol - Google Patents

Electrical apparatus for computing a check symbol Download PDF

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Publication number
US2776091A
US2776091A US231540A US23154051A US2776091A US 2776091 A US2776091 A US 2776091A US 231540 A US231540 A US 231540A US 23154051 A US23154051 A US 23154051A US 2776091 A US2776091 A US 2776091A
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Prior art keywords
relay
contact
digit
symbol
storage
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US231540A
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English (en)
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Chenus Pierre Jacques Charles
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Compagnie des Machines Bull SA
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Compagnie des Machines Bull SA
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    • G—PHYSICS
    • G06—COMPUTING OR CALCULATING; COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F11/00—Error detection; Error correction; Monitoring
    • G06F11/07—Responding to the occurrence of a fault, e.g. fault tolerance
    • G06F11/08—Error detection or correction by redundancy in data representation, e.g. by using checking codes
    • G06F11/10—Adding special bits or symbols to the coded information, e.g. parity check, casting out 9's or 11's
    • G06F11/1008—Adding special bits or symbols to the coded information, e.g. parity check, casting out 9's or 11's in individual solid state devices
    • G06F11/1012—Adding special bits or symbols to the coded information, e.g. parity check, casting out 9's or 11's in individual solid state devices using codes or arrangements adapted for a specific type of error
    • G06F11/104—Adding special bits or symbols to the coded information, e.g. parity check, casting out 9's or 11's in individual solid state devices using codes or arrangements adapted for a specific type of error using arithmetic codes, i.e. codes which are preserved during operation, e.g. modulo 9 or 11 check
    • G—PHYSICS
    • G06—COMPUTING OR CALCULATING; COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F7/00—Methods or arrangements for processing data by operating upon the order or content of the data handled
    • G06F7/38—Methods or arrangements for performing computations using exclusively denominational number representation, e.g. using binary, ternary, decimal representation
    • G06F7/40—Methods or arrangements for performing computations using exclusively denominational number representation, e.g. using binary, ternary, decimal representation using contact-making devices, e.g. electromagnetic relay
    • G06F7/42—Adding; Subtracting

Definitions

  • the present invention relates to calculating apparatus for effecting combinations in accordance with a given law so that said apparatus indicates at a given instant a certain result by a change in the condition of one of a group of output channels of the apparatus, and the energisation of one of a group of input channels of the apparatus results in a variation of the said change of condition from this output channel to another output channel as a func-v tion of the energised input channel and in accordance with the said law.
  • the broad object of the invention is to provide a calculating apparatus adapted to calculate from a number a checking symbol in terms of a base value N, the value of said checking symbol being equal to the difference between the sums of the digits of odd and even denominations of the number or to the complement to N of said difference.
  • the calculating apparatus essentially comprises a digit entering device to successively enter in true value the digits of a number, two result storage devices under control of control means whereby a single storage device is alternately operative at each digit entry, electrical switching members and connections which are of the type of the so-called columnshift arrangement, adapted in such a way that, when a digit is entered, the value of said entered digit is added to or subtracted from the value of the previously stored result according to which storage device was operative before said digit entry.
  • FIG. 1 illustrates the principle of one form of the invention
  • Figure 2' is a diagram corresponding to Figure 1
  • FIGS. 3-, 4 and 5 are similar diagrams corresponding to other forms of the invention.
  • Figure 6 is a diagram illustrating one embodiment of a calculating and checking apparatus according to a first embodiment
  • Figure 7 is a diagram illustrating a calculating and checking apparatus according to a second embodiment
  • Figure 8 shows a detail of Figure 6 illustrated in ditferent form
  • Figure 9 shows a third embodiment and checking apparatus.
  • apparatus comprising an assembly of members, preferably all identical and so disposed as to form a regular panel composed of a series of horizontal and vertical rows.
  • members of an electrical nature connected by electrical connecting of a calculating means will be considered, but it is to be understood that the invention is not limited to members of this type and that the said members may equally well be of magnetic, optical, hydraulic or other similar form, or of combined form, the connections made also being of corresponding nature.
  • ref- 2,776,091 Patented Jan. 1, 1957 erence is made to-an arrangement consisting of rows, or forming a panel, it isnot the material position which is to be considered, but the mutual connections of the elements with one another and with the external elements acting thereon.
  • a panel of members is provided in accordance with the invention as illustrated in Figure 1.
  • One of these members is diagrammatically indicated at 0, while the others are represented by dots for the sake of clarity of the drawing.
  • n members the panel being assumed to be square but it would also be possible without departing from the scope of the invention to provide a rectangular panel comprising nXp members, n and p being dillerent.
  • In the left-hand part of the figure there are 11 input channels E0 to En, corresponding respectively to the n horizontal rows and, at the top and bottom respectively, n-terminals or input channels A0 to An and B0 to En.
  • Each member 0 comprises three terminals or connections e, a,-b and has the following property: If it is energised at a and at e it transmits energisation to b. Preferably, if it is energised at b and at e it conversely transmits energisation to a.
  • This second property is not essential and examples of embodiment of the invention will be shown in which it is not utilised. It will first be assumed that this property exists.
  • the said members are readily conceivable and may vary considerably, that is, they may consist of relay controlled contacts, mechanical members or the like.
  • the members 0 are, in accordance with the invention, connected to the terminals or input members E, A and B as indicated by the continuous lines, that is to say, all the members of one horizontal row of the order x may be energised from a common input member Ex,
  • all the members of one vertical row of the order z may be energised from a common input ,member 'Bz or may transmit such energisation thereto,
  • supplementary inputs such as Ax could be provided, but it is preferable according to the preferred embodiment of the invention, to consider that the terminals A and B form cyclic assemblies of base 12, that is to say that the Relation 1 or 2 is accurate to within it.
  • the extension (in dot-and-dash lines) of the diagonal of the order y issues at By.
  • a combining panel of the type shown fin ,l Figure 1 may be employed 3 to. effect additions and subtractions. It may therefore be regarded as a calculating. arrangement.
  • auxiliary. members in order to adapt the said arrangement to a suitable form in accordance with the preferred embodiments of the invention, itis. necessary. to add. theretoat least someof, the following auxiliary. members:
  • Figure 1 may be diagrammatically:
  • ed to ma isell obtain th t the n ry -n m x in the calculating apparatus results in adding x when a result y is already stored therein, or in subtracting x when. a result. -z-- is already stored therein.
  • The. com tirntation of entering operations results in a. succession of alternate adding and. subtracting. operations.
  • Results 2 or y may, assume values. ranging. from-.Ofto n 1, n being the base value considered. If it is desired to begin a series of operations with an addition, it is suificient. to first enter. the value Ointhe storage device al loted to.results "-y; ifit. is desired, as the case maybe,
  • he mb nati may e. d utsd y gla ina e.
  • Fig. 3 represents a theoretical diagram wherein x is replaced by n-x, the increasing values running from B to A0.
  • the relevant formulas are:
  • n-z y.-
  • -nx that is: x--y for addition, and:
  • Each contact energises an entry relay R0 to RX while pairs to the recording electromagnets F0 to Fx on the one hand and to the indicating devices (lamps or the like) 0 to X on the other hand.
  • the circuits of the recording electromagnets (which recording is effected by punching or printing record cards or in a like manner) are completed by the closing of the contact CEand the indicating devices may be operated by closing of the contact CL.
  • the unidirectional elements A80 and ABO are also shown in Figure 6a.
  • a trigger arrangement is employed to feed the combining panel alternatively through its upper terminals A0 to Ax or through its lower terminals B0 to Bx, so that the symbol may be automatically calculated by successive differences as digits are entered into the arrangement by depressing the keys E0 to Ex.
  • the principle of such a trigger arrangement will be understood more clearly with reference to Figure 8, which shows the essential parts thereof.
  • the said arrangement comprises in symmetrical arrangement transformers TI or TS, the secondary winding of which feeds a relay RMI or RMS through a rectifier Al or AS, which loads a capacitor CI or CS at the terminals of the said relay.
  • MIK is one of the relays M10 to MIX of Figure 6a
  • MSK is one of the relays M50 to MSX.
  • I and S are utilisation arrangements, for example signalling arrangements.
  • E is a key. Assuming first that the trigger arrangement is not energised and that a voltage is momentarily applied to 'J by the contact U, MSK is traversed by a current and CSK is closed. An impulse is set up through AI, RMI is energised and CMI opens momentarily, which has no effect at this instant. S therefore remains energised by CSK. If the contact U is opened again and E is momentarily depressed, there are obtained by an analogous process the closing of CIK, an impulse in AS, the momentary opening of CMS and consequently the breaking of MSK.
  • the said symbol is so determined that the sum of the digits of even order of the number to be checked, including the symbol, is equal to the sum of the digits of uneven order, or the ditfiference between these sums is null, or equal to 11, or 22, or another multiple of the checking base.
  • thechecking base is 11 for checking decimal numbers.
  • this symbol is delivered at its output terminals; or the number 38420 is accompanied by its symbol already calculated, thus forming an aggregate datum (384208).
  • the calculating arrangement is used to verify the transcription of the number.
  • the current is set up at the positive and negative terminals in Fig. 6a.
  • contact CD will be opened to ensure the resetting of the arrangement, and then re-closed.
  • storage relay M80 is energized from the positive terminal through contacts CD, CRD and the return to negative terminal is effected through windings PTI and RD.
  • the circuit of M13 includes PTS which induces during the energisation of M13 an impulse in the trigger arrangement which temporarily opens CMS and breaks M80. As CMI is closed, M13 remains energised and indicates 3 through A133 ( Figure 6b) until the introduction of the following digit, which is 8.
  • E8 energises R8 which closes all the contacts of its horizontal row.
  • B3 is connected to A5 by the contact 85.
  • the positive voltage thus applied energises M and, through TI, energises the relay RMI which breaks CMI and de-energises M13.
  • the automatic operation of the trigger device ensures the alternate setting into activity of the upper storage device (MStl-MSX) and lower storage device (Mitt-MIX).
  • MStl-MSX upper storage device
  • Mitt-MIX lower storage device
  • the operation of the apparatus may be summarized by the succession of the result relays at the registering condition, namely: M13; M85; MIX; M53; M18.
  • the operator closes the key CL and sees that this digit is an 8, as being manifested by the operativeness of the indicator device 8, in parallel with relay M18, through terminal B8 and unidirectional element ABS.
  • electromagnet EB may, for instance, serve to control the printing mechanism and cause it to print, on the document under check, a distinctive mark indi- Upon closure of key CC 7 cating that no error was found during the checking process.
  • the Figure 7 shows a second embodiment of the invention in accordance with the diagram of Fig. 2 and established on the base value 10. It may be noted here that a checking digit or symbol calculated on base 10, nearly provides as good a security against errors as when calculated on base 11, on the condition that it also results from alternate additions and subtractions of the digits of the number handled.
  • the circuit Fig. 7 is substantially equivalent to that one shown by Fig. 6.1, within the number of relays.
  • Another relay trigger system is shown.
  • the trigger essentially comprises electro-magnet RBl, relay I and cam controlled contact 74, the latter being provided to alternately set under voltage holding lines 708 and 701. Such an alternation is effected at each energization of electro-magnet RBI.
  • the digit ent'ry relays R0-R9 are arranged in a normal order, as also are the storage relays MSO-MS9 and MIO-MI9.
  • the terminals A0-A9 and B0-B9 (Fig. 7) are respectively connected to the terminals with corresponding numbers All-A9 and 130-139 represented on Fig. 6b. This arrangement constitutes an application of the theoretical diagram of Fig. 2.
  • the first digit 7 is then introduced by the closing of contact E7.
  • This causes the energization of relay R7 and eletcromagnet RBI.
  • a circuit is completed from terminal A0, through one of the contacts controlled by R7, to terminal B7 and relay coil M17.
  • the pawl it controls is actuated and turns in a clockwise direction the ratchet wheel integral with cam 75, by a quarter of one revolution, thereby opening contact 74.
  • Relay 1 being deenergized, contact 1a returns to the rest position.
  • the movable blade of contact In must be of such a size and form that the positive voltage be not removed from line 703 before line 701 is itself set under voltage.
  • M80 is thus de-energized while M17 becomes energized and is held through its holding contact and line 701.
  • RB1 obviously is de-energized and a spring moves back the pawl Without changing the angular position of cam 75.
  • the introduction 'of the second digit 5 again causes the operation of the relay trigger which transfers contact Ia, thereby permitting the de-ener'gization of relay M17 and the held energization of relay M52.
  • the whole operation may be summarized by the storage relays successively energized, namely: MI7, M82, M18, and M87. 7
  • the indicator lamp '7 When the operator closes the key-contact C-L (Fig. 6b) the indicator lamp '7 will be lighted, manifesting the value of the resulting symbol. that is 7 which is the difference between the digits of odd denominations (7-
  • the operation of the arrangement according to Fig. 7 may be summarized by the succession of the storage relays sequentially energized, that is: M12; MSS; and M18.
  • FIG. 9 This embodiment is designed to give the same results as those given by the circuits shown by Figs. 6a6b and constitute also 'an application of the theoretical diagram of Fig. 5.
  • the values of the entry relays R0RX and storage relays MIX-M10 are allotted to said relays in orders contrary to the incremental order resulting from the vertical and oblique connections.
  • the base value is 11 and there is only one result storage device.
  • a common relay G controls the setting under 'voltage of one holding line and of one control line 101, by means of three contacts G1, G2, G3, two of which (G1 and G3) being contacts with delayed actuation.
  • the delay applies to closing as also to opening, and the delay of contact G1 is greater than that of contact G3.
  • Each storage relay controls a holding contact, C0 for instance, and one delayed contact C0d, for instance.
  • Push-button D controls the initial entry of 0 in the calculating apparatus.
  • EO-EX are push-buttons, each of which has one normally closed contact and one normally opened contact, to control the entry of the digits to be entered. Thanks to a spring action, all push-buttons return to normal position when released.
  • Output terminals A0-AX are to be connected to the indicating organs shown by Fig. 6b, in accordance with corresponding values.
  • the operation is as follows. Let the symbol corresponding to the number 63 be calculated.
  • the apparatus is set under voltage by closing key CD.
  • Relay G becomes energized by a circuit extending from positive terminal through key contact CD, wire 103a, relay coil G, Wire 104, the closed contacts E0-EX in series, wires 102e, 1020, 102a, to negative terminal.
  • the momentary actuation of D completes two circuits. The first one extends froin positive terminal I, through key contact CD, wire 103a, relay coil R0, wire 105, upper contact D, wires 1020!, 102c, 102a, to negative terminal thereby closing the horizontal row of contacts controlled by R0.
  • the second one through lower contact D, sets under voltage the wires a, 110b, 1100. It follows the energization of the storage relay M10, which holds itself energized through C0 and line 100.
  • R0 is de-energized but terminal A0 remains under voltage, thanks to contact C0d closed.
  • the first digit 6 is entered by depressing push-button E6, thereby breaking the energization circuit for relay G, and completing a circuit for relay R6, which closes its horizontal row of contacts.
  • Contact G2 is immediately opened but contact G3 reclose's a little later.
  • line 100 is no longer under voltage and relay M10 is de-energized. Due to the fact that the delay of G1 is greater than the delay of G3, terminal A0 remains under voltage a little time after re-closure of contact G3, permitting, during this time, the completion of a circuit extending from terminal through key contact CD, wires 103a,
  • relay R6 When push-button E6 is released, relay R6 is dc-east gized and relay G is energized again. As contact G3 is opened a little after contact G2 is closed, the holding circuit for relay M16 is not broken. Still a little after, terminal A6 is set under voltage through G1 closed, line 101, contact C6d closed and wire 116.
  • the indicating device 8 is now operative to display the symbol 8 corresponding to the number 63.
  • Electrical calculating apparatus for calculating from a number expressed in a numeration system of radix n a checking symbol in terms of a base value N and equal to the difference between the sum of the digits of the odd denominations and the sum of the digits of the even denominations of said number, or to the complement to N of said difference, comprising a digit entering device including a number n of entering relays, each assigned to introduce a distinct digit in the apparatus when operated, energizing means for selectively operating one of said entering relays, a first symbol storage device and a second symbol storage device comprising each a number N of storage relays, each relay either of said storage devices being assigned to one symbol value from 0 to N-l, control means made operative to control the successive operation of said first and second storage device alternately at each digit introduction in the apparatus, a circuit arrangement arranged as an addition table comprising a matrix of two-point make contacts with N columns and 22 rows, the contacts of each row being controlled by an associated one of said entering relays so that the contacts
  • each of said storage relays has individual holding means, and including two holding lines each associated with one of said storage devices, and switching means to set into activity at the start of operation a holding means for maintaining its energization, and including two holding lines each associated with one of said storage devices, and switching means to set into activity at the start of operationsa storage relay assigned to the 0 symbol in said first storage device, said control means cooperating with said digit entering device, and
  • Electrical calculating apparatus for calculating from a number expressed in a numeration system of radix n a checking symbol in terms of a base value N and equal to the difference between the sums of the digits of odd and even denominations of said number, or to the complement to N of said difierence, comprising a digit entering device including N entering relays, each assigned to introduce a distinct digit in the apparatus when operated.
  • energizing means for selectively operating one of said entering relays, a first symbol storage device and a second symbol storage device, each comprising a number N of storage relays, each relay in either of said storage devices being assigned to one symbol value from 0 to N1 and being fitted with individual holding means, two holding lines each associated with one of said storage devices, first switching means for making alive either of said holding lines, a circuit arrangement arranged as an addition table including a matrix of make contacts distributed in N columns and N contact rows, the contacts of each row being controlled by an associated one of said entering relays, so that the contacts of a different row will be closed according to which digit is being introduced in the apparatus, a first group of diagonal conductors in which group each conductor connects contacts pertaining to all the rows but to different columns of the matrix to a separate storage relay in said first storage device, a second group of conductors in which group each conductor connects the contacts of a single column to a separate storage relay in said second storage device, second switching means for energizing one storage relay of
  • Electrical calculating apparatus for calculating from a number expressed in a numeration system of radix n a checking symbol in terms of a base value N and equal to the difierence between the sums of the digits of odd and even denominations of said number, or to the complement to N of said difference, comprising a digit entering device including N entering relays, each assigned to introduce a distinct digit in the apparatus when operated, energizing means for selectively operating one of said entering relays, a first symbol storage device and a second symbol storage device, each comprising a number N of storage relays, each relay in either of said storage devices being assigned to one symbol 11 value from 0 -to N-l and being fitted with individual holding means, two holding lines each associated with one of said storage devices, first switching means for making alive either of said holding lines, a circuit arrangement arranged as an addition table including 'a matrix of makecontacts distributed in N columns and N contact rows, the contacts of each row being controlled by an associated one of said entering relays, so that the contacts of a different

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Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2886239A (en) * 1954-02-16 1959-05-12 Willem Hendrik Theodorus Helmi Check symbol computer
US2969912A (en) * 1957-02-26 1961-01-31 Ibm Error detecting and correcting circuits
US2970764A (en) * 1954-06-04 1961-02-07 Ibm Checking circuit
US3017091A (en) * 1957-03-26 1962-01-16 Bell Telephone Labor Inc Digital error correcting systems
US3098994A (en) * 1956-10-26 1963-07-23 Itt Self checking digital computer system
US3191009A (en) * 1961-08-17 1965-06-22 Sperry Rand Corp Check digit verifiers
US3431406A (en) * 1958-07-03 1969-03-04 Sperry Rand Corp Check digit verifiers
US3448254A (en) * 1965-07-28 1969-06-03 Anker Werke Ag Data checking system

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US2244700A (en) * 1939-09-21 1941-06-10 Bell Telephone Labor Inc Telephone system
US2364540A (en) * 1942-10-10 1944-12-05 Ibm Calculating machine
US2404250A (en) * 1944-01-22 1946-07-16 Rca Corp Computing system
US2428811A (en) * 1943-10-30 1947-10-14 Rca Corp Electronic computing device
US2434499A (en) * 1944-11-10 1948-01-13 Ibm Relay computing mechanism
US2436178A (en) * 1943-10-21 1948-02-17 Rca Corp Electronic computer for transforming polar into rectilinear coordinates
GB614639A (en) * 1943-10-04 1948-12-20 Jean Eugene Paul Verneaux Improvements in electrical apparatus for performing arithmetical calculations
US2486809A (en) * 1945-09-29 1949-11-01 Bell Telephone Labor Inc Biquinary system calculator
US2502360A (en) * 1947-03-14 1950-03-28 Bell Telephone Labor Inc Electronic computer
US2538636A (en) * 1947-12-31 1951-01-16 Bell Telephone Labor Inc Digital computer
GB650685A (en) * 1947-02-26 1951-02-28 John Albert Lawrence Electromechanical calculating machine
US2565511A (en) * 1948-04-27 1951-08-28 Int Standard Electric Corp Register system

Patent Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2244700A (en) * 1939-09-21 1941-06-10 Bell Telephone Labor Inc Telephone system
US2364540A (en) * 1942-10-10 1944-12-05 Ibm Calculating machine
GB614639A (en) * 1943-10-04 1948-12-20 Jean Eugene Paul Verneaux Improvements in electrical apparatus for performing arithmetical calculations
US2436178A (en) * 1943-10-21 1948-02-17 Rca Corp Electronic computer for transforming polar into rectilinear coordinates
US2428811A (en) * 1943-10-30 1947-10-14 Rca Corp Electronic computing device
US2404250A (en) * 1944-01-22 1946-07-16 Rca Corp Computing system
US2434499A (en) * 1944-11-10 1948-01-13 Ibm Relay computing mechanism
US2486809A (en) * 1945-09-29 1949-11-01 Bell Telephone Labor Inc Biquinary system calculator
GB650685A (en) * 1947-02-26 1951-02-28 John Albert Lawrence Electromechanical calculating machine
US2502360A (en) * 1947-03-14 1950-03-28 Bell Telephone Labor Inc Electronic computer
US2538636A (en) * 1947-12-31 1951-01-16 Bell Telephone Labor Inc Digital computer
US2565511A (en) * 1948-04-27 1951-08-28 Int Standard Electric Corp Register system

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2886239A (en) * 1954-02-16 1959-05-12 Willem Hendrik Theodorus Helmi Check symbol computer
US2970764A (en) * 1954-06-04 1961-02-07 Ibm Checking circuit
US3098994A (en) * 1956-10-26 1963-07-23 Itt Self checking digital computer system
US2969912A (en) * 1957-02-26 1961-01-31 Ibm Error detecting and correcting circuits
US3017091A (en) * 1957-03-26 1962-01-16 Bell Telephone Labor Inc Digital error correcting systems
US3431406A (en) * 1958-07-03 1969-03-04 Sperry Rand Corp Check digit verifiers
US3191009A (en) * 1961-08-17 1965-06-22 Sperry Rand Corp Check digit verifiers
US3448254A (en) * 1965-07-28 1969-06-03 Anker Werke Ag Data checking system

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FR1020239A (fr) 1953-02-03

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