In the late 1800s, German inventor Otto Büttner designed two groundbreaking mechanical calculating machines. While not commercially successful themselves, Büttner‘s patented devices marked innovations in automation and demonstrated the promise of mechanical calculation. His 1883 Schaltklinke mechanism particularly foreshadowed 20th century breakthroughs.
Overview and Context
Büttner created his first patented calculator in 1883 at a time of rapid advancement in mechanical automation of mathematics. Inventors across Europe competed to design machines that could reliably perform chained arithmetic operations automatically. Gottfried Leibniz first conceived the stepped drum mechanism in the 1600s, while Blaise Pascal built one of the earliest working mechanical calculators in the 1640s.
By Büttner‘s era, the field saw continuous refinements to calculating machines along with intermittent major leaps incorporating new mathematical approaches. Integrating the emerging Schaltklinke "switching latch" mechanism rather than the classic Leibniz stepped drum, Büttner‘s first patented device proved one such innovative leap. His calculators also presaged later commercially successful machines from inventor Christel Hamann.
The 1883 Schaltklinke Mechanism Patent
Büttner‘s first patented calculator design from 1883 represented a pioneering advance by utilizing the newer Schaltklinke or "switching latch" mechanism for automated mathematical calculation. Invented by Jacob Leupold and used in a few subsequent machines, the switching latch consisted of a rotating cylindrical cam with depressions that could engage an pawl to in turn rotate a counting gear wheel by precise increments.
Each number wheel could get selectively engaged and disengaged in sequence, enabling reliable chained calculation. This contrasted with previous designs prone to inaccuracies as gear slippages accumulated. Büttner configured sliding levers to set digits and intermediate gears to transfer the numeric input to output dials, achieving a reliable calculator in a compact 37 x 10 x 21 cm, 5.4 kg desktop machine:
| Specification | Value |
|---|---|
| Dimensions | 37 x 10 x 21 cm |
| Weight | 5.4 kg |
| Digit Precision | Up to 20 digits |
| Key Innovations | Schaltklinke mechanism, single lever function switching |
Contemporary reviewers commended the device‘s comparative simplicity versus competing machines as well as its affordability. However, Büttner only produced a few copies, including one for the Royal Saxon Statistical Bureau.
The 1884 Pinwheel Mechanism Design
Büttner patented a second calculating machine design in 1888, this one based on the traditional pinwheel architecture. Patented with his partner Wilhelm Brückner, it weighed over 8 kg and calculated up to 20 digits through a technical complexity that impeded commercial success.
However, Büttner‘s first Schaltklinke-based machine proved the more enduring influence and promise. The Royal Saxon Statistical Bureau assessed this device for daily practical use and found it reliable, convenient, and uncomplicated compared to alternatives. Büttner unsuccessfully tried manufacturing more units out of Saxony, limited by business challenges rather than flaws in the underlying invention.
Influence on Future Computing Innovations
While never mass-produced, Büttner‘s 1883 breakthrough device directly presaged the pathbreaking calculating machines of German inventor Christel Hamann decades later. Hamann extensively utilized the Schaltklinke mechanism at industrial scales, evolving Büttner‘s architecture to power his eponymous adding machines manufactured internationally since the 1920s.
In retrospect, Büttner helped progress mechanical calculation from unreliable early efforts by pioneers like Pascal and Leibniz to the automated digital computers that ultimately realized their visions of advanced mathematical automation. Situated between these eras, Büttner represented the methodical nineteenth century scientific approach of testing and evolving calculator architectures through several iterations until hitting upon durable designs. The immense human labor at mechanical calculation aimed specifically at eventual replacement by machinery.
Büttner contributed two such iterations that not only proved functionally reliable themselves, but provided foundations for other inventor‘s commercially successful devices shortly thereafter. By persistently channeling humanity‘s mathematical ambitions into physical form, Büttner offered pivotal momentum toward today‘s ubiquitous computation.
