Portrait of Donát Bánki



Our century is also called the century of motorization, but at the sight of or sitting in cars sweeping along, do we think of the person to whom we owe this dashing, the magic of the buzzing engine?

To a Hungarian engineer, Donát Bánki. His figure, bearded, almost always with a cigar in his hand, has been faded away by time, but his creations have remained, by which he wrote his name in the history of the world's technical culture. He was one of the greatest personalities among Hungarian mechanical engineers. He had one passion: cigars, because this was the one which he could indulge in while working as well.

The memories of the family have also faded in the course of time, but this cloud of smoke has recently been recalled even by his only living grandchild: "When we visited my grandparents with my parents, I would always see my Grandfather in the midst of a big cloud of smoke in the house on Rose Hill. He liked smoking cigars and smoking a pipe as well."

He was born in a small village in Komárom County called Bakonybánk on 6 June, 1859. His father had been the head physician of the military during the 1848 revolution and war of independence; he guarded the spirit of 1848 even after decades had passed, and he raised his children in this spirit.

Donát Bánki was nine years old when his father was transferred to Lovászpatona as a district medical officer. As the majority of children today, Bánki was also amazed by the enormous paddle wheel of the water mill at Lovászpatona.

When he was a student in Pápa, he also went out to the mill there once in a while; then it was operating, now it can only be seen in ruins. These memories of childhood also contributed to the fact that after decades had passed, he began to engage himself in hydraulics. The student years in Pápa were followed by the ones in Budapest, where, having successfully passed his grammar school leaving examination, he became a student of the Faculty of Mechanical Engineering of the Technical University.

The economic and social developments in 19th-century Hungary were determined by three important – interconnected – chains of events: the Reform Period, the 1848-49 revolution and war of independence, and the 1867 reconciliation.

The period following the 1867 compromise was the age of modern industrial development, of the formation of large-scale mechanical industry particularly.

Parallelly with industrial developments, the traffic and civic design of Pest-Buda also showed considerable changes in the course of the second half of the 19th century. The funicular to Castle Hill was completed in 1870, and the cog-wheel railway to Sváb Hill started to operate in 1874. In 1887, the first tram set off between the Western Railway Station and Király Street. In 1861, at least six years before Siemens and Wheatstone, Ányos Jedlik discovered the principle of the dynamo.

Mechanical engineer Donát Bánki, whose essay on gas engines won the 100-florin award of the Technical University in 1880, when he was 21, contributed to the international recognition of Hungarian industry, as this study of his was published not only in Hungarian but in German as well. He was a graduating student when professor Ignác Horváth assigned him as an assistant to the Department of Mechanics.

As a young mechanical engineer, he was employed as a designer in the Hungarian Royal State Railway Machine Works in 1881, then he worked in the Ganz and Co. Iron Casting and Machine Works for 17 years. He started his factory career as a designer, and finished it as an engineer-in-chief. It was here that he prepared and patented his first significant invention, the dynamometer serving for measuring peripheral force of belt-driven power transmissions, generally used at that time. His invention, published as well, received the Hollán award in 1877. (This award was founded by the Hungarian Society of Engineers and Architects in recognition of the services rendered by its first president, Ernő Hollán.)

He received the Hollán award again for his study titled 'Theory of Gas Engines' in 1893. "The study of Donát Bánki titled 'Theory of Gas Engines' unites all the properties that make it primarily worth being awarded by the importance, originality, and formal perfection of the subject. The study deals with a subject not duly appreciated so far by special literature. It is superfluous to emphasize the significance and current validity of the subject since the role of gas engines in small-scale industry is commonly known, and it is also well-known how rapidly the application of gas engines has been spreading in the last few years. (...)

By virtue of all these properties, this treatise of Donát Bánki is excellent in the Hungarian and even in the international technical literature. Dated in Budapest, 16 February, 1893."

During the first year of his activity at the Ganz Works, he was assigned to take charge of the instalment of the Elevator then under construction (destroyed during World War II), serving to unload the corn supplies arriving on the Danube at the railway station in Ferencváros. He solved this task so well, that András Mechwart, the general manager of the factory, commissioned him to develop his own invention, the rotary plough. Bánki converted the plough into a steam-engine device, which constituted a completely new solution at the time.

"You have gained significant merits in constructing the Mechwart-type steam and petroleum ploughs," company manager Jenő Cserháti wrote about Bánki in a record dated 21 October, 1898, "by having overcome the difficulties, not infrequently considerable ones, met with in the course of the experiments going on for several years with great skill and lucky ingenuity. (...)"

The designer achieving more and more significant results – as an assistant at the Technical University –, got into close working relationship with János Csonka, the master mechanic of the engineering shop at the University.

Their fruitful cooperation is earmarked by several patents.

  • 19 January, 1889: Innovation on gas engines

  • 14 March, 1889: Camshaft for four-stroke engines

  • 11 April, 1889: Innovations on gas and petroleum engines

  • 31 October, 1890: Gas and petrolem hammer

  • 11 February, 1893: Innovations on petroleum engines

In the latter, the principle of the first petrol atomizer, the so-called "carburettor" was explained.

As a result of the innovations and patents in succession the Bánki-Csonka motor appeared, and with it the mass production of gas and petroleum engines in the Ganz Works. The most important innovation regarding the engine, the carburettor, constituted one of the most significant steps in the development of combustion engines. The device, according to their patent specification, explaining the principle of the atomizer clearly and unambiguously, is theoretically the same, as the ones used today all over the world. The name of the device is also due to them. The French patent application by Maybach relative to the carburettor is half a year later, but since the inventor patented it as an independent device, he could secure greater protection for it. This fact, however, does not decrease the significance of the invention of Donát Bánki and János Csonka. Although this invention, currently produced in hundreds of millions, established the basis for automobilism, Bánki went up to his Rose Hill villa on foot all his life...

The fuel for the first combustion engines was gas, mainly coal gas. Naturally, this set narrow limits to their applicability. In the history of combustion engines, the "industrial turning point" was produced by the use of an easily transportable fluid fuel – petroleum at the beginning. The adequate explosive mixture – of petroleum or petrol gas with air –, necessary for the operation of combustion engines, was difficult to produce since petrol was dangerous because of its explosiveness, petroleum however would only evaporate and mix with air at a higher temperature. Thus the composition of the explosive mixture was not constant, which had a strong impact on the stable running of the engine.

This is written in their patent application dated 11 February, 1893: "Our machine is supplied without a petroleum pump, as long as the petroleum quantity required for each cylinder charging is swept along by the air sucked into the machine. The petroleum inlet opening is constantly open, so speed must be regulated by blocking air suction.

When the piston goes down the valve opens and sucks air into the conic part of the cylinder through a pipe..., while sweeping along... fluid fuel from... the dashpot... connected to the fuel tank. The fluid swept along by the stream of air..., is replaced from the tank evenly,... due to the interposed dashpot..., the advantage and result of which is that the quality of the mixture will not change. A cone serves to control the opening."

The patent specification is a clear and unambiguous description of the principle of the atomizer, documenting the fact that their invention took half a year's precedence over Maybach's. Therefore they were indubitably the first all over the world.

And the idea? János Csonka recalled it as follows:

"Seeing how florists blow water with their glass blowpipes in a pulverized form to water their flowers, I told Bánki that we should evaporate petroleum or petrol the same way to achieve a perfect combustion. Some days after this observation we got together with assistant professor Bánki and constructed the atomizer together in professor Asbóth's laboratory."

In 1894, Bánki patented his first high-pressure combustion engine, later to be called Bánki-engine. Still in 1894, Donát Bánki's twin-cylinder motorbike was completed, and in 1898, his engine with water injection was produced. The decisive structural element of this latter was the double Bánki-carburettor, bringing well-deserved international recognition to the creator of this invention, of great significance both from the theoretical and the practical point of view.

The activity of Donát Bánki at the Ganz Works ended in 1898, but he stayed to act as a technical advisor of the factory. He was invited to head the Department II of Mechanical Construction Engineering (Machine Elements and Hoisting Engines) of the Technical University, then a year later he took over the lead of the Department III of Mechanical Construction Engineering (Hydraulics and Hydraulic Machinery).

Tódor Kármán remembered his sometime professor as follows: "As regards creative thinking, I learnt the most from professor Donát Bánki, a lean, narrow-faced, goateed, decent gentleman at the university. He was a mechanical engineer, teaching hydraulics. He was against applying purely empirical rules in mechanical engineering, and attempted to explain us at least approximately, why things happen in nature the way they really do."

When the buildings of the Technical University were being built in Lágymányos at the beginning of the present century, Bánki managed to have a caloric and a hydraulic engine laboratory constructed as well. His laboratory was so well-equipped, as the similar laboratories abroad.

At the present Technical University, the heritage of Bánki is principally carried on by the Department of Hydraulic Machinery. The self-portrait of Donát Bánki is preserved in the room of the head of department. In the department laboratory, future mechanical engineers prepare for their noble tasks. His course books and special articles have been read by many generations.

He also utilized his industrial experience in his teaching work, enriching engine technology by further inventions. In 1898, he submitted his patent for a water-pulverization, high-compression engine, which soon became produced in the Ganz Works; both its performance and consumption showing conspicuously good results. (Such an engine was exhibited and received an award at the Paris World Fair in 1900).

From 1908 on, Bánki concerned himself with flying, so to say, the fashion of the age. The issue of stabilizing aircrafts particularly engrossed his attention, and mentioned it in his university lectures as well.

In the middle of the 18th century, János András Segner operated a mill near Göttingen with a device now considered to be the precursor of the turbine. Donát Bánki first presented the design of his own turbine in a study written in German in 1917, and later in the Millers' Periodical in Hungarian. It is a solution capable mainly of utilizing small hydraulic powers – as it was indicated by Bánki himself as well -, serving principally to replace the paddle wheels of mills or to modernize water mills. The corporation selling Bánki-type water turbines produced and put into operation 853 turbines until 1928. This still modern hydraulic engine is manufactured in many countries at present times.

During the decades of Donát Bánki's creative activity, he applied for several patents. His major inventions amount to about 20, and nearly 150 of his special publications are known. Several of them were particularly recognized by the Hungarian Society of Engineers and Achitects; his book titled 'Energy Transformations in Fluids' was awarded a gold medal (1917).

From the end of the 19th century on, more and more patented Hungarian inventions were produced and sold in Hungary and abroad as well, among them those of Bánki, who became a corresponding member of the Hungarian Academy of Sciences in 1911. He was invited to be a guest professor at universities abroad several times, but he did not accept the invitations. The patriotic feeling he received from his father when he was a child proved to be a maxim influencing all his life: "I deem it to be my patriotic obligation to stay at the Technical University of Budapest and serve the cultural and economic development of my homeland" he wrote answering the invitation of the university of Zurich.

During the First World War, another large-scale project engrossed his attention, namely the hydro-electric power station to be built at Vaskapu (lower Danube, where now a power station is operating, built in cooperation by Rumania and Yougoslavia). In his proposal submitted he also dealt with the utilization of the energy produced: he wanted to conduct the electrical energy to Budapest, and to solve simultaneously the irrigation problem of the Great Hungarian Plain. The project would have facilitated the navigation on the lower Danube and the electrification of townships in the Hungarian Plain.

During the hours of leisure he liked painting. "Bánki was not only our neighbour in Buda, but a good friend of my father's," as Tódor Kármán recalled this period, continuing his recollections as follows: "He liked to paint as an amateur. He would always ask me to pose for him." These pictures have not survived, unfortunately, but some of his paintings preserve his touches.

He was already suffering with illness when he heard that the mill at Lovászpatona – the far-away world of childhood – had received a Bánki-type engine. He would have liked to go there and see the old days and his creation in it. All this remained to be only a dream.

"The Hungarian engineering profession is in deep mourning. One of those few has left us for ever who went off the beaten path – one of the great researchers presented by Fate rarely even to nations much greater than we are. Donát Bánki was one of the greatest." The date was 1 August, 1922 as calendars showed.

In his farewell speech, among other things, Emil Schimanek thus appreciated the work of the great predecessor: "I should characterize Bánki, the scholar, the machine designer of genius, the excellent professor, the outstanding specialist, the admirable colleague, and last but not least, the noble-hearted man, this warm-hearted apostle of sincerity and justice, who can be put as an example to be followed on the pedestal where only the most eminent ones of the country can be placed."