The pinwheel calculator as we know it was invented by Willgodt Theophil Odhner in around 1871. He was Swedish, but was working in Russia at the time for Ludvig Nobel, an oil magnate. Pinwheels had been used before in various forms, but never in large numbers because the precise engineering needed for manufacturing it is difficult. At almost the same time as Odhner in Russia, Frank Baldwin in the USA developed his own pinwheel calculator, but had difficulty selling it. Odhner made a few machines for Nobel, but it wasn't until 1890 that he had an improved design that was easier to make, and had set up a workshop in St. Petersburg to start producing them. The next year he also opened a production plant in Germany, but soon found it too difficult to oversee two such widely separated locations, and in 1892 the German plant was sold to Grimme, Natalis & Co, together with all its equipment, designs and patent licenses to manufacture the Odhner calculator for the German, Belgian and Swiss market.
The company Grimme, Natalis & Co was set up in November 1871 by Carl Grimme and Kaufmann A. Natalis. They were both sewing machine manufacturers who had decided to join forces. They also made other metal household apparatus, like ovens and heaters. In 1892 they began making pinwheel calculators in their plant in Braunschweig (Brunswick) using the brand name Brunsviga, which is the latin name for the town. Their first models, models A and B, were exact copies of the Odhner design, but with different numbers of digits. Soon their main engineer and co-director Franz Trinks devised several improvements (such as safety interlocks) and new designs. It took many years for the market for calculators to develop, but through extensive advertising using the slogan "Gehirn von Stahl" (Brains of Steel), demand grew. Eventually the demand for calculators even began to outgrow that of sewing machines.
While Brunsviga was the first Odhner clone, others would follow, especially after Odhner's patents expired. For example Triumph, Thales, Walther, Facit, Felix, Tiger, and many others. Willgodt Odhner died in 1905, and his sons took over the company. In the Russian revolution the Odhner company was confiscated, so the Odhner brothers returned to Sweden and started anew with the Original-Odhner company. In Russia the confiscated assets were used to produce the Felix brand of pinwheel calculators.
Meanwhile in Germany, Grimme Natalis & Co released a new series of models in 1925, the "Nova" series, which shared many interchangable parts for ease of production and repair. In 1927 the company incorporated the brand name into its company name, changing it to "Brunsviga-Maschinenwerke Grimme, Natalis & Co ", because by then it was producing calculators almost exclusively.
Competition between calculator companies was fierce, and in 1957 Brunsviga was bought by Olympia-Werke, a company that spun off from AEG and which made mostly typewriters. So from then on Brunsviga was once again merely a brand name. By 1963 the only mechanical calculator model they still produced was the Olympia-Brunsviga 13 RM, and in 1969 the last plant that still produced this machine, located in Spain, stopped too.
The "Nova" series of models is the culmination of almost all of Franz Trink's developments. The Nova II was the most popular, and a little over 10,000 Nova II machines were produced from 1925 till 1934. The Nova I had fewer digits, and the Nova III had an extra revolution counter without a carry mechanism. Franz Trinks retired soon after this, and the Brunsviga pinwheel machines remained essentially unchanged until the 1950s. It has many clever features:
One of the few innovations not used in the Nova are longer stationary input pins. Some earlier models had input pins that did not rotate with the pinwheels when the crank was turned, which allowed them to be longer and more comfortable to use. This mechanism must have been considered too expensive or complicated to continue with.
My machine has serial number 6T 2O 864. Note that is the letter O. The first thousand had the numbers 6T 2N xxx, the next thousand 6T 2O xxx, then 6T 2P xxx, after which they switched to a fully numerical format of 103,000 onwards.
The paint on the top cover is crackled, and flaking off quite badly. Mechanically it is in reasonable condition. It mostly works fine, if a little stiffly, except that clearing the input sometimes leaves one of the digits set to 1. The back transfer also sometimes doesn't quite fully push the input pins to the correct position.
Below is a video I made that demonstrates the Brunsviga Nova II.
In 1957, Brunsviga was bought by Olympia-Werke, a company that spun off from AEG and which made mostly typewriters, but also some pinwheel calculators. In the 1960s, Olympia gradually stopped producing most mechanical calculator models, moving to electric and electronic ones. The mechanical model that continued the longest was the Olympia-Brunsviga 13 RM. It is a fairly standard pinwheel machine, with back transfer. They were mostly manufactured in Spain, and the ones sold in Spain itself used the brand name Minerva. Other than the name, the Minerva is identical to the Olympia-Brunsviga 13 RM.
It uses a standard pinwheel design, clearly from the Olympia stable rather than the Brunsviga. It has its 8-digit revolution counter in the carriage, to the left of the 13-digit results register. The add/subtract switch is shifted to a neutral position when the counter is cleared, and the direction of the next turn of the crank shifts it to the correct state. To do a back transfer, first clear the input, push down the back-transfer button which is located to the right of the register, and then clear the register.
This Minerva has serial number 30091, and is in reasonable condition. It works correctly, except that the back-transfer mechanism does not always quite push the input pins back to their correct places.
After removing the four rubber feet the bottom plate comes free. This gives access to the screws on the sides that keep the top part of the casing in place.
Here are various leaflets promoting the Brunsviga calculators.
Différents Modèles Nova-Brunsviga
212mm × 281mm
148mm × 210mm
148mm × 210mm
Here are a various advertisements relating to Grimme Natalis & Co, their Brunsviga calculators, and to Olympia.
Here are some articles related to Grimme, Natalis & Co., and Brunsviga calculators.
Die Rechenmaschine Brunsviga
Modern Instruments and Methods of Calculation, a Handbook of the Napier Tricentenary Exhibition
The Calculating Machines
(1925, Ernst Martin)
Elementary Mathematics from an Advanced Standpoint
(1932, Felix Klein)
|Patent||Filing date||Published date||Name||Description|
|DE 124,578||07-07-1900||21-10-1901||Franz Trinks||Lock crank/input when clearing|
See also AT 9,031 B, GB 1900/19,762
|DE 126,743||26-06-1900||08-01-1902||Franz Trinks||Lock input when crank turns|
See also AT 9,034 B, GB 1900/19,762
|FR 344,541||07-09-1904||07-11-1904||Franz Trinks||Input register|
|AT 30,756 B||16-11-1905||25-11-1907||Franz Trinks||Lock input when shifting carriage|
|AT 30,763 B||16-11-1905||25-11-1907||Franz Trinks||Overshoot prevention|
|DE 185,005||07-11-1905||16-05-1907||Franz Trinks||Lock input through pin at crank handle|
|AT 32,602 B||19-10-1906||10-04-1908||Franz Trinks||Independent input pins|
See also FR 6,833 E, GB 1906/23,659
|FR 362,969||21-04-1906||18-07-1906||Franz Trinks||Carry mechanism lever|
|US 843,506||06-03-1906||05-02-1907||Franz Trinks||Input lever arrangement|
|DE 203,659||26-10-1907||29-10-1908||Franz Trinks||Counter with complemetary digits|
See also AT 39,207 B, CH 45,340, DK 12,416 C, FR 395,531, GB 1908/22,435, US 935,565
|US 975,180||13-06-1907||08-11-1910||Franz Trinks||Fixed counter|
|AT 43,003 B||29-03-1909||11-07-1910||Grimme, Natalis & Co.||Carriage shift by button press|
See also CH 50,241, FR 409,262, US 967,821
|AT 43,677 B||29-03-1909||25-08-1910||Franz Trinks||Back transfer|
|DE 224,131||25-07-1908||12-07-1910||Grimme, Natalis & Co.||Register locking mechanism|
See also AT 47,275 B, CH 49,626, DK 13,282 C, US 953,622
|DK 13,284 C||10-07-1909||30-05-1910||Grimme, Natalis & Co.||Carriage shift mechanism|
See also CH 49,628, FR13873E, FR 406,992, US 946,367
|AT 59,385 B||24-04-1912||26-05-1913||Franz Trinks||Block input when clearing register|
See also CH 59,698, FR 443,343, GB 1912/10,604, US 1,040,059
|AT 61,307 B||12-10-1912||25-09-1913||Franz Trinks||Input display register|
See also CH 61,229, FR 449,723, GB 1912/24,275
|AT 63,783 B||02-01-1913||10-03-1914||Franz Trinks||Ratcheted clearance mechanism|
See also CH 62,620, FR 452,838
|AT 66,728 B||18-10-1913||25-09-1914||Franz Trinks||Carry mechanism|
See also CH 66,344, FR 463,789, GB 1913/25,754
|AT 66,729 B||22-12-1913||25-09-1914||Franz Trinks||Carry mechanism|
See also CH 67,131, FR 466,956, GB 1914/00,037, US 1,098,193, US 1,100,631
|AT 68,733 B||16-03-1914||25-05-1915||Franz Trinks||Carry mechanism improvement|
See also CH 68,850, FR 470,156, GB 1914/07,963, US 1,134,780
|AT 68,992 B||27-03-1914||10-06-1915||Franz Trinks||Optionally copied input|
See also CH 71,871, GB 1914/08,867, US 1,118,829
|FR 467,396||17-01-1914||10-06-1914||Carl Rasmussen; Grimme, Natalis & Co.||Carry mechanism|
|AT 72,870 B||06-08-1915||27-12-1916||Franz Trinks||Lock crank when pins not aligned|
See also CH 71,476, FR 520,006, GB 147,114, US 1,220,029
|CH 72,515||29-11-1915||02-06-1916||Grimme, Natalis & Co.||Lock crank when pins not aligned|
See also US 1,194,900
|CH 72,990||27-11-1915||01-08-1916||Grimme, Natalis & Co.||Pin alignment|
|CH 72,991||27-11-1915||17-07-1916||Franz Trinks||Lock crank when pins not aligned?|
|CH 91,917||16-06-1920||01-12-1921||Franz Trinks||Mechanism for shifting window on counter|
|DE 321,611 C||23-04-1919||09-06-1920||Franz Trinks||Counter register with complementary digits and sliding window|
See also SU 10,427
|DE 325,901 C||18-04-1919||09-01-1922||Franz Trinks||Counter register with complementary digits and sliding window|
See also AT 86,598 B, CH 90,733, DE 325,902 C, DE 325,903 C, SU 10,427,US 1,445,461
|AT 90,434 B||10-12-1920||27-12-1922||Franz Trinks||Fixed counter above input |
See also CH 91,167, FR 528,855, GB 157,898
|DE 354,897 C||21-06-1921||20-06-1922||Grimme, Natalis & Co.||Mechanism for shifting window on counter|
|DE 359,634 C||18-12-1921||25-09-1922||Grimme, Natalis & Co.||Input alignment mechanism|
|DE 377,424 C||15-09-1922||18-06-1923||Grimme, Natalis & Co.||Lock for transport|
|DE 378,838 C||01-11-1922||06-08-1923||Grimme, Natalis & Co.||?? shifting mechanism|
|DE 383,722 C||31-10-1922||17-10-1923||Grimme, Natalis & Co.||?? Register clearing mechanism disengages clicking mechanism|
|DE 384,531 C||22-08-1922||03-11-1923||Grimme, Natalis & Co.||Input clearing mechanism|
|DE 386,578 C||21-11-1922||21-12-1923||Grimme, Natalis & Co.||Number wheel|
|DE 390,460 C||29-03-1923||19-02-1924||Franz Trinks||Warning bell on counter with sliding window|
See also AT 99,483 B, CH 108,102, DK 34,004 C, FR 577,413, GB 213,549
|DE 393,955 C||20-06-1923||11-04-1924||Franz Trinks||Carriage shifting mechanism|
|DE 396,316 C||21-03-1922||02-07-1924||Grimme, Natalis & Co.||Input clearing disengages clicking mechanism|
|CH 107,414||09-02-1924||16-10-1924||Grimme, Natalis & Co.||Pinwheel|
See also DK 33,854 C, FR 577,245, GB 212,540
|AT 99,766 B||07-02-1924||25-04-1925||Franz Trinks||Warning bell on counter with sliding window|
See also CH 108,220, DK 34,136 C, FR28776E, GB 212,561
|AT 101,809 B||20-09-1924||25-11-1925||Grimme, Natalis & Co.||Crank handle cradle lock|
See also CH 110,312, DK 35,306 C, FR 586,482, GB 224,212
|CH 110,311||03-09-1924||01-06-1925||Grimme, Natalis & Co.||Carriage shift mechanism|
See also DK 34,566 C, GB 223,895, SU 5,719
|GB 212,548||03-03-1924||22-01-1925||Grimme, Natalis & Co.||Shifting carriage rack|
|GB 223,894||08-10-1924||11-06-1925||Grimme, Natalis & Co.||Number wheel|
|GB 224,211||04-10-1924||12-03-1925||Grimme, Natalis & Co.||Single tooth drive|
|CH 113,198||23-03-1925||02-01-1926||Grimme, Natalis & Co.||Clearing indicator|
See also GB 233,672
|DE 401,412 C||02-03-1924||04-09-1924||Grimme, Natalis & Co.||decimal point indicators|
|DE 404,370 C||17-04-1924||18-10-1924||Grimme, Natalis & Co.||carry mechanism|
See also DE 412,945 C, FR 595,063, GB 232,577
|DE 404,887 C||14-05-1924||25-10-1924||Grimme, Natalis & Co.||Clearing mechanism|
See also CH 112,987, DK 35,289 C, GB 234,061
|DE 405,482 C||17-04-1924||06-11-1924||Grimme, Natalis & Co.||carry mechanism|
See also GB 232,567
|DE 408,461 C||11-04-1924||29-01-1925||Grimme, Natalis & Co.||Guard against crank reversal|
|DE 409,297 C||22-06-1924||05-02-1925||Grimme, Natalis & Co.||Lock input|
|DE 411,403 C||12-10-1924||20-03-1925||Grimme, Natalis & Co.||Decimal point indicator|
|DE 412,373 C||02-10-1924||21-04-1925||Grimme, Natalis & Co.||Lock input|
|DE 415,284 C||18-04-1924||12-02-1928||Grimme, Natalis & Co.||pins in two sections|
|DE 416,830 C||24-12-1924||27-07-1925||Grimme, Natalis & Co.||Carry mechanism|
|DE 419,313 C||20-12-1924||08-10-1925||Grimme, Natalis & Co.||Simplified number wheel construction|
See also AT 102,415 B, CH 113,197, DK 35,372 C, GB 229,301
|DE 426,140 C||20-12-1924||09-03-1926||Grimme, Natalis & Co.||Improved pinwheel|
See also AT 102,414 B, CH 112,632, DK 35,119 C, FR 596,069, GB 228,902
|DE 414,135 C||21-09-1923||17-02-1926||Grimme, Natalis & Co.||Calculation mechanism timing|
See also CH 118,488, DK 35,686 C, SU 7,077
|DE 416,040 C||15-01-1925||07-07-1925||Grimme, Natalis & Co.||Carriage alignment during back transfer|
See also GB 230,828
|DE 416,828 C||04-02-1925||27-07-1925||Grimme, Natalis & Co.||Turn direction indicator|
|DE 417,288 C||05-02-1925||10-08-1925||Grimme, Natalis & Co.||Backtransfer interlock|
See also CH 118,033, DK 36,935 C, FR 610,268
|DE 417,396 C||04-02-1925||14-08-1925||Grimme, Natalis & Co.||Backtransfer|
See also CH 118,489, DK 36,934 C, FR 610,247, SU 7,076
|DE 418,746 C||27-02-1925||21-09-1925||Grimme, Natalis & Co.||Backtransfer interlock|
See also CH 118,490, DK 36,936 C, FR 610,269, SU 8,380
|DE 418,749 C||20-02-1925||21-09-1925||Grimme, Natalis & Co.||Clearing mechanism for register|
See also CH 117,597, DK 36,643 C
|DE 437,284 C||30-04-1926||18-11-1926||Grimme, Natalis & Co.||Crank cradle pincer|
Rechnerlexikon has a page for the
Rechenmaschinen-Illustrated has a many Brunsviga models.
Rechnen Ohne Strom is an interesting site that has a page about Brunsviga/Olympia.
John Wolff has a page about Brunsviga models.
The Odhner Calculator, Memorial site has information about the early pinwheel machines by Odhner.
John Wolff has many Brunsviga models and a section about a Brunsviga Exposition.
© Copyright 2019 Jaap Scherphuis, mechcalc a t jaapsch d o t net.