Jaap's Mechanical Calculators Page


Brunsviga Nova II

Brunsviga and the Pinwheel calculator
Brunsviga Nova II
Promotional material

Brunsviga and the Pinwheel calculator

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.

Brunsviga Nova II

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.

Brunsviga Nova II
Brunsviga Nova II
Brunsviga Nova II
Brunsviga Nova II
Brunsviga Nova II
Brunsviga Nova II
Brunsviga Nova II
Brunsviga Nova II
Brunsviga Nova II
Brunsviga Nova II
Brunsviga Nova II
Brunsviga Nova II
Brunsviga Nova II
Brunsviga Nova II
Brunsviga Nova II
Brunsviga Nova II

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.

Brunsviga Nova II
Brunsviga Nova II
Brunsviga Nova II
Brunsviga Nova II
Brunsviga Nova II
Brunsviga Nova II


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.


Promotional material

Here are various leaflets promoting the Brunsviga calculators.

Différents Modèles Nova-Brunsviga
4-page leaflet
212mm × 281mm

Nova II-IV9
December 1929
Trifold leaflet
148mm × 210mm

Nova 13-13Z
March 1930
Trifold leaflet
148mm × 210mm


Here are a various advertisements relating to Grimme Natalis & Co, their Brunsviga calculators, and to Olympia.

1883-08-01 journal of domestic appliances
1885-10-01 journal of domestic appliances
1889-01-22 Export
1889-12-02 journal of domestic appliances
1894-01 Stahl und Eisen
1896-02-10 Het nieuws van de dag
1897-11-14 Algemeen Handelsblad
1901-02-16 scientific american
1903-10-20 Provinciale Noordbrabantsche en 's Hertogenbossche courant
1903-10-23 Provinciale Noordbrabantsche en 's Hertogenbossche courant
1904-04-16 Die Woche
1904-05-14 Die Woche
1906-11-24 Journal fur die reine und angewandte Mathematik
1909-05-25 De Tijd
1909-09-06 De Telegraaf
1909-11-10 Algemeen Handelsblad
1910 The Fixing Of Rates and Fares
1914-04-08 Tammerfors Nyheter
1915-04 Zeitschrift fur Mathematik und Physik
1916-07-05 Nieuwe Rotterdamsche Courant
1919-09-13 Svenska Tidningen
1921-03-17 De Preanger-bode
1921-04-01 De Maasbode
1921-06-03 Algemeen Handelsblad
1922-06-13 Algemeen Handelsblad
1922-10-05 Uusi Suomi
1926-06-12 Pilsner Tagblatt
1928-11-13 Suomen Sosialidemokraatti
1928-11-28 De Maasbode
1928-11-30 De Maasbode
1928-12-05 De Maasbode
1928-12-05 Helsingin Sanomat
1928-12-11 Algemeen Handelsblad
1928-12-12 De Maasbode
1928-12-18 Algemeen Handelsblad
1929-01-11 Suomen Sosialidemokraatti
1929-03-01 Helsingin Sanomat
1929-04-06 Maaseudun Tulevaisuus
1929-08-15 Helsingin Sanomat
1929-10-08 Helsingin Sanomat
1929-11-09 Keskisuomalainen
1930-01-28 De Telegraaf
1935-10-17 Algemeen Handelsblad
1952-02-02 De Preangerbode
1952-08-30 De vrije pers
1953-04-01 De locomotief
1953-07-14 De Preangerbode
1958-08-30 Algemeen Handelsblad
1958-11-29 Algemeen Handelsblad
1959-10-10 De Volkskrant
1960-01-09 Algemeen Handelsblad
1961-01-21 Algemeen Handelsblad


Here are some articles related to Grimme, Natalis & Co., and Brunsviga calculators.

1873-08-30 Wiener Welt-Ausstellung
1873-09-06 Wiener Welt-Ausstellung
1885-04-01 journal of domestic appliances
1892-09-10 Schweizerische Bauzeitung
1892-10-02 journal of domestic appliances
1893-11-24 De Maasbode
1893-11-27 Het nieuws van de dag
1893-12-01 Leeuwarder Courant
1899-04-12 De Telegraaf
1899-04-21 Algemeen Handelsblad
1899-05-18 Het nieuws van den dag
1901-04-23 Het nieuws van den dag voor Nederlandsch-Indie
1902-09  Zeitschrift fur Instrumentenkunde
1903-12-30 Report on the organization and working of railways in America
1905-08-04 The Railroad Gazette
1911-07 Royal Statistical Society Journal

Die Rechenmaschine Brunsviga
(1897-08-18, Prometheus)

1897-08-18  Prometheus 1
1897-08-18  Prometheus 2
1897-08-18  Prometheus 3
1897-08-18  Prometheus 4
1897-08-18  Prometheus 5

Modern Instruments and Methods of Calculation, a Handbook of the Napier Tricentenary Exhibition

1914 Modern Instruments Napier Tricentenary 1
1914 Modern Instruments Napier Tricentenary 2
1914 Modern Instruments Napier Tricentenary 3
1914 Modern Instruments Napier Tricentenary 4
1914 Modern Instruments Napier Tricentenary 5
1914 Modern Instruments Napier Tricentenary 6
1914 Modern Instruments Napier Tricentenary 7

The Calculating Machines
(1925, Ernst Martin)

1925 Ernst Calculating Machines 1
1925 Ernst Calculating Machines 2
1925 Ernst Calculating Machines 3
1925 Ernst Calculating Machines 4
1925 Ernst Calculating Machines 5

Elementary Mathematics from an Advanced Standpoint
(1932, Felix Klein)

1932 Elementary Mathematics 1
1932 Elementary Mathematics 2
1932 Elementary Mathematics 3
1932 Elementary Mathematics 4
1932 Elementary Mathematics 5
1932 Elementary Mathematics 6


PatentFiling datePublished dateNameDescription
DE 124,57807-07-190021-10-1901Franz TrinksLock crank/input when clearing
See also AT 9,031 B, GB 1900/19,762
DE 126,74326-06-190008-01-1902Franz TrinksLock input when crank turns
See also AT 9,034 B, GB 1900/19,762
FR 344,54107-09-190407-11-1904Franz TrinksInput register
AT 30,756 B16-11-190525-11-1907Franz TrinksLock input when shifting carriage
AT 30,763 B16-11-190525-11-1907Franz TrinksOvershoot prevention
DE 185,00507-11-190516-05-1907Franz TrinksLock input through pin at crank handle
AT 32,602 B19-10-190610-04-1908Franz TrinksIndependent input pins
See also FR 6,833 E, GB 1906/23,659
FR 362,96921-04-190618-07-1906Franz TrinksCarry mechanism lever
US 843,50606-03-190605-02-1907Franz TrinksInput lever arrangement
DE 203,65926-10-190729-10-1908Franz TrinksCounter 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 975,18013-06-190708-11-1910Franz TrinksFixed counter
AT 43,003 B29-03-190911-07-1910Grimme, Natalis & Co.Carriage shift by button press
See also CH 50,241, FR 409,262, US 967,821
AT 43,677 B29-03-190925-08-1910Franz TrinksBack transfer
DE 224,13125-07-190812-07-1910Grimme, Natalis & Co.Register locking mechanism
See also AT 47,275 B, CH 49,626, DK 13,282 C, US 953,622
DK 13,284 C10-07-190930-05-1910Grimme, Natalis & Co.Carriage shift mechanism
See also CH 49,628, FR13873E, FR 406,992, US 946,367
AT 59,385 B24-04-191226-05-1913Franz TrinksBlock input when clearing register
See also CH 59,698, FR 443,343, GB 1912/10,604, US 1,040,059
AT 61,307 B12-10-191225-09-1913Franz TrinksInput display register
See also CH 61,229, FR 449,723, GB 1912/24,275
AT 63,783 B02-01-191310-03-1914Franz TrinksRatcheted clearance mechanism
See also CH 62,620, FR 452,838
AT 66,728 B18-10-191325-09-1914Franz TrinksCarry mechanism
See also CH 66,344, FR 463,789, GB 1913/25,754
AT 66,729 B22-12-191325-09-1914Franz TrinksCarry mechanism
See also CH 67,131, FR 466,956, GB 1914/00,037, US 1,098,193, US 1,100,631
AT 68,733 B16-03-191425-05-1915Franz TrinksCarry mechanism improvement
See also CH 68,850, FR 470,156, GB 1914/07,963, US 1,134,780
AT 68,992 B27-03-191410-06-1915Franz TrinksOptionally copied input
See also CH 71,871, GB 1914/08,867, US 1,118,829
FR 467,39617-01-191410-06-1914Carl Rasmussen; Grimme, Natalis & Co.Carry mechanism
AT 72,870 B06-08-191527-12-1916Franz TrinksLock crank when pins not aligned
See also CH 71,476, FR 520,006, GB 147,114, US 1,220,029
CH 72,51529-11-191502-06-1916Grimme, Natalis & Co.Lock crank when pins not aligned
See also US 1,194,900
CH 72,99027-11-191501-08-1916Grimme, Natalis & Co.Pin alignment
CH 72,99127-11-191517-07-1916Franz TrinksLock crank when pins not aligned?
CH 91,91716-06-192001-12-1921Franz TrinksMechanism for shifting window on counter
DE 321,611 C23-04-191909-06-1920Franz TrinksCounter register with complementary digits and sliding window
See also SU 10,427
DE 325,901 C18-04-191909-01-1922Franz TrinksCounter 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 B10-12-192027-12-1922Franz TrinksFixed counter above input
See also CH 91,167, FR 528,855, GB 157,898
DE 354,897 C21-06-192120-06-1922Grimme, Natalis & Co.Mechanism for shifting window on counter
DE 359,634 C18-12-192125-09-1922Grimme, Natalis & Co.Input alignment mechanism
DE 377,424 C15-09-192218-06-1923Grimme, Natalis & Co.Lock for transport
DE 378,838 C01-11-192206-08-1923Grimme, Natalis & Co.?? shifting mechanism
DE 383,722 C31-10-192217-10-1923Grimme, Natalis & Co.?? Register clearing mechanism disengages clicking mechanism
DE 384,531 C22-08-192203-11-1923Grimme, Natalis & Co.Input clearing mechanism
DE 386,578 C21-11-192221-12-1923Grimme, Natalis & Co.Number wheel
DE 390,460 C29-03-192319-02-1924Franz TrinksWarning 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 C20-06-192311-04-1924Franz TrinksCarriage shifting mechanism
DE 396,316 C21-03-192202-07-1924Grimme, Natalis & Co.Input clearing disengages clicking mechanism
CH 107,41409-02-192416-10-1924Grimme, Natalis & Co.Pinwheel
See also DK 33,854 C, FR 577,245, GB 212,540
AT 99,766 B07-02-192425-04-1925Franz TrinksWarning bell on counter with sliding window
See also CH 108,220, DK 34,136 C, FR28776E, GB 212,561
AT 101,809 B20-09-192425-11-1925Grimme, Natalis & Co.Crank handle cradle lock
See also CH 110,312, DK 35,306 C, FR 586,482, GB 224,212
CH 110,31103-09-192401-06-1925Grimme, Natalis & Co.Carriage shift mechanism
See also DK 34,566 C, GB 223,895, SU 5,719
GB 212,54803-03-192422-01-1925Grimme, Natalis & Co.Shifting carriage rack
GB 223,89408-10-192411-06-1925Grimme, Natalis & Co.Number wheel
GB 224,21104-10-192412-03-1925Grimme, Natalis & Co.Single tooth drive
CH 113,19823-03-192502-01-1926Grimme, Natalis & Co.Clearing indicator
See also GB 233,672
DE 401,412 C02-03-192404-09-1924Grimme, Natalis & Co.decimal point indicators
DE 404,370 C17-04-192418-10-1924Grimme, Natalis & Co.carry mechanism
See also DE 412,945 C, FR 595,063, GB 232,577
DE 404,887 C14-05-192425-10-1924Grimme, Natalis & Co.Clearing mechanism
See also CH 112,987, DK 35,289 C, GB 234,061
DE 405,482 C17-04-192406-11-1924Grimme, Natalis & Co.carry mechanism
See also GB 232,567
DE 408,461 C11-04-192429-01-1925Grimme, Natalis & Co.Guard against crank reversal
DE 409,297 C22-06-192405-02-1925Grimme, Natalis & Co.Lock input
DE 411,403 C12-10-192420-03-1925Grimme, Natalis & Co.Decimal point indicator
DE 412,373 C02-10-192421-04-1925Grimme, Natalis & Co.Lock input
DE 415,284 C18-04-192412-02-1928Grimme, Natalis & Co.pins in two sections
DE 416,830 C24-12-192427-07-1925Grimme, Natalis & Co.Carry mechanism
DE 419,313 C20-12-192408-10-1925Grimme, 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 C20-12-192409-03-1926Grimme, 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 C21-09-192317-02-1926Grimme, Natalis & Co.Calculation mechanism timing
See also CH 118,488, DK 35,686 C, SU 7,077
DE 416,040 C15-01-192507-07-1925Grimme, Natalis & Co.Carriage alignment during back transfer
See also GB 230,828
DE 416,828 C04-02-192527-07-1925Grimme, Natalis & Co.Turn direction indicator
DE 417,288 C05-02-192510-08-1925Grimme, Natalis & Co.Backtransfer interlock
See also CH 118,033, DK 36,935 C, FR 610,268
DE 417,396 C04-02-192514-08-1925Grimme, Natalis & Co.Backtransfer
See also CH 118,489, DK 36,934 C, FR 610,247, SU 7,076
DE 418,746 C27-02-192521-09-1925Grimme, Natalis & Co.Backtransfer interlock
See also CH 118,490, DK 36,936 C, FR 610,269, SU 8,380
DE 418,749 C20-02-192521-09-1925Grimme, Natalis & Co.Clearing mechanism for register
See also CH 117,597, DK 36,643 C
DE 437,284 C30-04-192618-11-1926Grimme, Natalis & Co.Crank cradle pincer


Rechnerlexikon has a page for the Nova II.
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, .