TECHNICAL DATA of the Mechanical Calculator BRUNSVIGA-10 ************************************************************************* Serial-Number: 138576 Dimensions: (ca.) Width = 8_3/4" / 22 cm Depth = 7 " / 18 cm Height = 3_1/2" / 9 cm Weight: (ca.) 8 lbs / 3.5 kg Mechanics: Split-Stepped Drum Functions: Add, Subtract, Multiply, Divide Registers: Input = 6 Decimals Counter = 5 Decimals (Neg.Figures RED) Arithmetic = 10 Decimals Manufacturer: BRUNSVIGA MASCHINENWERKE GRIMME, NATALIS & CO. A.-G. Braunschweig Germany 1935 BASICS & HOW TO USE the BRUNSVIGA-10 **************************************** BASIC SETTINGS: =============== (a) Main-Crank: --------------- For addition (+) the crank is turned clockwise; for subtraction (-) the crank is turned counter-clockwise. In the idle position the crank is DOWN & LOCKED. To make one or more turns with the crank, pull out the handle to unlock. When finished the turn(s), let the handle snap into lock again. The locked down position only makes other functions (ex. clearing) accessible. REMARK: Every started turn has to be finished completely! Accidentally started turns are correctible somehow. (b) Clearing Registers: ----------------------- The input has to be cleared by pressing the right lever on front The counter unit will be cleared with the crank on the upper left side The arithmetic register will be cleared with the crank on the right side of the carriage (c) Shifting the Carriage: -------------------------- The carriage can be pulled out to the right by hand. Pressing down either the left or right silver lever, let the carriage move one step to the left. The left position "1" is the "Start Position" of the carriage. (d) Counting Direction: ----------------------- After clearing the counter, a white mark shows its neutral state. It depends of the 1st turn of the main crank what happens: When (for addition) the 1st turn is clockwise, the counter shows white figures; when (for subtraction) the 1st turn is counter-clockwise, the counter shows red figures. In both cases the counter will work with 10s-carry and allows "Shortened Method of Multiplication". ADDITION & SUBTRACTION: ======================= Example: 123 + 45 - 6 = 162 Clear input, counter and arithmetic units. ADD: Enter the first number (123) in the far right of the input unit. Make a positive (clockwise) turn with the crank to transfer the number into arithmetic unit. The counting unit displays the figure 1. Enter the second number (45). Make a positive (clockwise) turn with the crank to add the number. The arithmetic unit displays the intermediate sum (168) and the counting unit displays the figure 2. SUBTRACT: Enter the third number (6). Make a negative (counter-clockwise) turn with the crank. The arithmetic unit displays the result (162) and the counting unit is decreased by 1. REMARK: NEGATIVE RESULTS are displayed in the arithmetic unit as the COMPLEMENT of the next higher 10, 100, 1000, ... Example: -12 = 99...9988 MULTIPLICATION: =============== Example: 123 x 45 = 5535 Clear input, counter and arithmetic units. Enter the multiplicand (123) in the far right of the input unit. The multiplicator (45) has two digits, so the carriage is shifted to position 2. Make positive (clockwise) turns with the crank, until the first figure of the multiplicator (4) will appear in the 2nd position of the counter unit. Shift the carriage to position 1. Repeat positive turns with the crank, until the second figure of the multiplicator (5) appears in the 1st position of the counter unit. The multiplication is done: The multiplicand (123) stays in the input unit, the multiplicator (45) in the counter and the result (5535) is in the arithmetic unit. DIVISION: ========= Example: 22 : 7 = 3.1428 Remainder 4 Division requires 3 steps: (1st) To Set the Dividend into Arithmetic Unit: ----------------------------------------------- For the maximum number of decimals, pull out the carriage to the far right position. Enter the dividend (22) in the far right of the input unit. Make a positive (clockwise) turn with the crank to transfer into arithmetic unit. (2nd) To Set the Divisor into Input Unit: ----------------------------------------- Clear counter & input units. Enter the divisor (7) under the dividend (22). (3rd) To Divide: ---------------- Make negative (counter-clockwise) turns with the crank until the arithmetic unit shows an "underflow". Make one positive (clockwise) turn with the crank. Move the carriage to the next left position. Repeat this procedure until the required number of decimals ... The result (3.1428) is in the counter (in RED), and the remainder (4) is in the arithmetic unit. The divisor (7) stays in the input unit, therefore an additional decimal can be estimated... ( 5, cause 5 x 7 = 35). R E M A R K S : ========================================================================= Remark to History: ------------------ The calculator came in bad shape - found in a dumpster ??? Dirty, rusty, bent and dent ... If the machine could tell their story, it would be an interesting one: The inventory tag reads BUNDESGESUNDHEITSAMT / ROBERT KOCH INSTITUT Remarks to Restoration: ----------------------- (1) After cleaning, the machine could NOT RESET TO ZERO properly, because the worn-out mechanics. To prevent that the RESET COMB in the axle of the ARITHMETIC UNIT snaps in his PARK POSITION GAP just before all figures are reset to zero ... ... the TIP OF A WIRE (glued-in on top of the right side) guards the worn-out edge of the park position gap. (2) The input decimal marker bar was missing. A new INPUT MARKER BAR with MARKERS out of brass sheet is home-made ... (3) The BELL was not active. Because the hammer is not to adjust in working conditions, the central hole in the bell was made oval: Now the bell is adjustable in hight relative to the hammer until the sound is right. impressum: ************************************************************************* © C.HAMANN http://public.beuth-hochschule.de/~hamann 07/30/08 |