CURTAThe universal pocket
System C. Herzstark
|Weight 230 gr.|
|CONTINA S.A. Mauren/Liechtenstein|
|For the exact time:|
|the pocket watch ...|
|For taking pictures:|
|the miniature camera...|
|high precision pocket calculating machine,|
performing the four arithmetic operations.
Contina S.A. launches a novelty: the universal pocket calculating machine, robust and efficient. It is a high precision item, constructed according to the principles of fine-mechanical mass production and with the experience of several decades provided by the designer C. Herzstark specializing in the construction of calculating machines.
The picture above shows that the dimensions of this machine are extremely small. One can easily hold it in one hand or put it in ones pocket without any inconvenience. It answers to the long term demand by calculators who wished a less cumbersome machine that could be used anywhere, and it therefore fills a niche that has always existed for calculating machines.
The Curta is the indispensable aid for traveling merchants,
the building contractor on the construction site, the technician
in his workshop, the designer at his drawing board, the
scientist in his lab, and the student. Every place where
the use of a noisy machine would be intolerable and where it isn't possible or
practical to bring a heavy and cumbersome machine, like during surveying,
the eminent qualities of the CURTA render it indispensable.
In commercial or technical offices, in
banks and administrative offices as well as behind the
counter, the CURTA is especially appreciated for its easy handling.
In fact, until now it was not possible for an operator to use his machine
directly on his writing pad. Therefore he paid the extra effort of numerous
movements of his body, his hands, his head and his eyes, to and from his
writing pad and the calculating machine.
The advantages of the Curta have gained it the approval without reserve of
professionals, and a considerable demand for it from all over the world.
With the Curta a high precision calculating machine has been realized that equals the universal hand driven machines, millions of which are spread all over the world. According to more than one report the Curta is superior to many of them, most notably by its simplicity and convenient operation.
|Fig. 1: Writing space = calculating space|
|Fig. 2: Writing space | calculating space|
The numbers (for example the numbers to be added, one of the two factors of the multiplication, or the divisor of the division) are set by means of the sliding knobs. It suffices to displace the knob corresponding to the unit of the digit desired (tens, hundreds, thousands) until that digit appears in the corresponding setting window.
Control of the number set is simple because all digits remain visible in a horizontal line in the setting windows.
The crank that drives the mechanism of the machine has a stop that can be felt easily, and helps in counting the number of revolutions during the calculation. When the crank is pulled or pushed along its axis, the mechanism moves between two positions, the lower one for augmentative calculations (adding, multiplication) and the upper one for diminutive calculations (subtraction, division). In both cases the crank has to be turned clockwise, a special stop preventing it from being turned in the opposite direction.
The revolution counter (digits in the clear segment) counts the number of revolutions made by the crank and indicates for addition the number of terms; for multiplication, the multiplier; for division, the quotient; for calculation of a root, the root. The revolution counter is operated on at the window corresponding to the position of the carriage indicated by the arrow.
The totalisator (digits in the black segment) indicates for addition, subtraction and multiplication, the result. For division, it indicates, depending on the calculation method used, the remainder or the dividend.
The continuous carrying of tens on both counters enables a considerable speed-up for many operations and reduces the number of revolutions of the crank (e.g. for multiplication using the 'simplified method'). It also enables the addition of multipliers (important for instance for cubatures, the calculation of interests etc. ...).
Setting the counters to zero is done by the handle with a ring (see fig. 3 and 4). It can be rotated in two directions. It has two, clearly indicated, stop positions where the clear segment borders the black one. Both counters can be set to zero in one movement, or each separately.
The machine viewed
from the back
Sample calculation. The numbers shown in figures 3 and 4 are those of the following multiplication: 645 432 x 63 992. The multiplicand can be seen in the control windows (fig. 3), the multiplier on the revolution counter and the product on the totalisator (fig. 4).
The time required for this calculation, including setting the numbers, is about 15 seconds with 29 revolutions of the crank. But if the simplified method of multiplication is used, made possible by the continuous carrying of tens, the time required is about 10 seconds, with only 13 revolution of the crank.
A division with a 6 digit quotient takes 30 seconds on average, including setting the numbers.
All other operations can be done in a minimum amount of time, using methods already known for ordinary machines.
|The protective anti-shock case|
of the Curta
|View of the precision mechanism of the Curta|
View of the Curta without its hull
and with detached carriage.
Schematic view of
of the Curta.
In the Curta subtraction is reduced to an addition by means of a vertical displacement of the stepped drum, that, when in its upper position, lets a complementary number of teeth engage with the setting gears. These simple operating principles enable a rational and robust construction, which ensures the reliability of the Curta.
|Building I, Mauren|
|Building II, Eschen|
Reproduction of texts and illustrations, even partial, is prohibited
without our permission and without indication of the source.
Illustrations and descriptions can be subject to minor modifications.
34 51 6 f
Andries de Man