Patent GB-716158-A (GB)
Title: Improvements in or relating to a record card controlled accounting machine
IPC: G06F11/10
Filed: 1952-08-21
Abstract: 716,158. Statistical apparatus. INTERNATIONAL BUSINESS MACHINES CORPORATION Aug. 21, 1952 [Nov. 14, 1951], No. 21007/52. Class 106 (1) A record card controlled calculating machine arranged to enter a multidigit amount is characterized in that means are provided for entering the units and alternate digits of the amount in a predetermined substitute form while the tens and alternate digits are entered in original form, and means are provided for computing the units digit of the sum of the entered digits. A checking symbol or digit is then obtained by subtracting the units digit of the sum of the entered digits from 10 to obtain the tens complement which figure becomes the checking symbol and is entered in the machine with the original number. The rule of substitution employed conforms to the following table:- original digit 0, 1, 2, 3, 4, 5, 6, 7, 8, 9. substituted digit 0, 2, 4, 6, 8, 1, 3, 5, 7, 9. Taking for example the number 257348 and making the substitution we have:- original number . 257348 substituted number 217647 Adding the digits of the substituted number with tens cast out gives 7, the tens complement of which is 3, i.e., the checking symbol or check digit, the original number may now be recorded as 2573483. It is apparent therefore that upon cross addition of the digits of the original number with substitutions made as before and the check digit included in the addition, the result will be zero. If the result is other than zero an error is indicated and the machine may be stopped. The apparatus referred to in the description and drawings is substantially the same as a known card punch described in Specification 684,273, [Group XV]. With the initiation of a machine cycle the main shaft will rotate causing cams P1, P2, P3, P4, P5, P6, P7 and P8 to make and break such as shown in the timing diagram of Fig. 2a. Assuming that it is required to originate the key number for a postal order bearing the serial number 1235 then when the cam controlled contacts P6 make at 180 degrees of the first cycle the 1 value standing in storage relay R107, Fig. 1c will be transferred into the storage relay R112. A hold circuit for this relay is established by the cam controlled contacts P2 through contacts R112a. When the operator depresses the 2 key 50 in order to punch the next higher digit in column 2 of the detail card two circuits are established, one operates the escape movement to advance the card one column, the other operates the punch magnet to cause the digit 2 to be punched in the detail card. At 180 degrees of the second cycle when contacts P6 close the value standing in the relay R104 will be transferred to the relay R109 which is representative of 5 value. At the end of the second cycle as shown in Fig. 2b the relays R114, R101, R118, R116 and R109 are all energized. When the 3 key 60 is depressed by the operator to commence the third cycle, the corresponding 3 interposer magnet 188, Fig. 1a, will be energized causing the programme card to escape to column 4 while the detail card will escape to column three. The programme card bears a "4" perforation which causes the relay R117 to be energized causing the substitute relay R102 to be energized. Thus the total of the first three digits of the serial number with a 4 value substituted for the second digit is now temporarily entered in the relays R104, R106 and R107 which are respectively representative of the values 5, 2 and 1 equal to a sum of 8. At 180 degrees of the third cycle the total standing in the relays R104, R106 and R107 will be transferred to the relays R109, R111 and R112. The fourth cycle is commenced by depressing the 5 key 66 which will result in the tens digit of the serial number being punched in the fourth column of the detail card. The corresponding 5 interposer magnet 188 causes the programme card to escape to column five, when the perforations " 12," " 4," and " 5 " are sensed causing the relay R101 to continue to hold, and energizing relay R117 and also energizing relay R116. At this stage relays R104 and R105 are storing the sum of the four digits entered with the second and fourth digit substituted. At 180 degrees of the fourth cycle the values in relays R 104 and R105 are transferred to relays R109 and R110. At 86 degrees of the next (fifth) cycle the cam controlled contacts P5 will make and establish a circuit for reading out the tens complement of the value stored in relays R104 and R105. This circuit may be traced from the cam controlled contacts P5 inductor 33, Fig. 1a, as follows, contacts R114d now closed, R103e now closed, R108c as shown, R109c shifted, R105c transferred, conductor 80 the 1 interposer magnet 188, conductor 34 and then conductor 14. The energization of the 1 interposer magnet 188 initiates a normal punch cycle representing the key number 1 being punched in the fifth column of the record card. A similar circuit arrangement is described for checking a record card which already bears a serial number having a check number appended thereto.