Two-wheel tractor or walking tractor (, , ) are generic terms understood in the US and in parts of Europe to represent a single-axle tractor, which is a tractor with one axle, self-powered and self-propelled, which can pull and power various farm implements such as a trailer, cultivator or harrow, a plough, or various seeders and harvesters. The operator usually walks behind it or rides the implement being towed. Similar terms are mistakenly applied to the household rotary tiller or power tiller; although these may be wheeled and/or self-propelled, they are not tailored for towing implements. A two-wheeled tractor specializes in pulling any of numerous types of implements, whereas rotary tillers specialize in soil tillage with their dedicated digging tools. This article concerns two-wheeled tractors as distinguished from such tillers.
Definition
Research has identified several terms used to identify the two-wheel tractor including: "walk-behind tractor, iron-ox, walking tractor, mechanical ox, ox-machine, pedestrian tractor, hand tractor, single-axle tractor, and in Asia, tok-tok".
There is also a bit of confusion in the nomenclature regarding machines with similar size or configuration, that operate a single implement (such as power tillers, rear-tine tillers, rotary hoes, rotary ploughs, rotary tillers and rotavators etc.).
The important distinction between a two-wheel tractor and any of these machines is that the two-wheel tractor is a single-axle machine where the operator usually walks behind it or rides the implement being towed and is designed to operate multiple interchangeable implements.
On the hand, the machines in the other categories above typically only operate one implement (such as a tiller) which is often an integral part of the machine (rather than being removable).
The "power tiller" can be understood as a garden tiller or rototiller of the small () petrol/gasoline/electric powered, hobby gardener variety; that are often sold as a rotary tiller, though the technical agricultural use of that term refers solely to an attachment to a larger tractor.
Alternatively, the term "power tiller" or "rotary tiller" as is understood in Asia and elsewhere is the rubber- or iron-wheeled, self-propelled machines of usually powered by heavy-duty single-cylinder diesel engines (and many Asian countries historically have had to pay a high luxury tax on petrol/gasoline).
Adding to the nomenclature confusion, agricultural engineers like to classify them as the single-axle tractor. For clarity, the rest of this article refers to the self-propelled, single-axle, multi-attachment tractive machines called the two-wheel tractor.
For agricultural production in the past and in the present, the two-wheel tractor accepts a wide range of implements for soil-working such as the: rototillers, moldboard plow, disc-plow, rotary plow, root/tuber harvesting plow, small subsoiler plow, powered and non-powered harrow, seeders, transplanters, and planters ( zero till and no-till planters) and seeders.
In plant protection and weed control, two-wheel tractor implements consist of various inter-cultivators and sprayers. For harvesting forage available two wheel tractor implements are: sickle bar mowers, disk mowers, hay rakes, hay tedders, hay balers and bale wrappers [for silage production].
For grain harvest the available implements are: reaper or grain harvesters, reaper-binders, and even combine harvesters [although typically only for Asian two-wheel tractors].For transport, trailers with capacities from 0.5 to 5 plus ton cargoes are available.
The general mowing implements consist of lawn mowers, brush mowers, and flail mowers and for snow removal the implements consist of snowblowers, power sweepers, and snow or dozer blades. Other implements include: chipper/shredders, log splitters, electrical generator, pressure washer, crimper-roller, fertilizer/salt/lime spreader, and stump grinder.
This list of implements is inexhaustible which means that the two-wheel tractors can execute practically all of the chores done by larger 4-wheel tractors, with the exception of items like front-loaders, which obviously have the physical stability requirements of a 4-wheel (two-axle) tractor.
This confusion over, or perhaps just ignorance of the utility of 2-wheel tractors, persists even at research and institutional levels. The United Nations' Food and Agriculture Organization's own statistical database, FAO Stat gauges levels of agricultural mechanization by numbers of 4-wheel tractors and ignores completely the fact that 2-wheel tractors often perform much, or even exactly, the same work as done by 4-wheeled models. By using FAO's statistics, international donors and agricultural research and development centres assume that as Bangladesh and Sri Lanka have very few 4-wheel tractors, they are completely unmechanized compared to (e.g.) India, which have a large population of them (besides 300,000 two-wheel tractors). Yet, when two-wheel tractors are included, Bangladesh and Sri Lanka are the most highly mechanized countries in south Asia in terms of area farmed using mechanized tillage. Two-wheel tractors are also extremely common for agricultural use in the mountainous countries of Europe (Italy, France, Spain, Germany, Switzerland, Austria, etc.), and as of 2015, there are at least 15 brands of two-wheel tractors of Italian origin alone.
History by country in chronological order
Development of single-axle tractors and power tillers worldwide began in the early 20th century and for many decades involved a mixture of people working independently in local contexts and, in other cases, of people expanding on the inspiration provided by others' work in distant locales, learned about via exports, travel (whether for jobs, business, or military service), or reading (magazines, newspapers, journals). The homegrown instances and the interwoven threads are discussed in subsequent sections.
Europe
In 1910, Dr. Konrad von Meyenburg of Basel, Switzerland, applied for a patent for a "Machine for Mechanical Tillage". Patent Number 1,018,843 was granted on February 27, 1912. He then licensed his patent to Siemens-Schuckertwerke of Berlin, Germany. Siemens, an electrical manufacturer, built their first two-wheel tractor with rotovator Bodenfräse (rotovator or literally soil grinder) using an electric motorized two-wheel tractor and a long extension cord in 1911. The idea was quickly abandoned and Siemens began using two and four cycle single cylinder internal combustion gasoline/petrol or diesel engines to power their two-wheel tractors. Around 1932 Siemens sold off its cultivator division and focused on its electrical applications. Mr. Eberhard Bungartz of Munich, Germany, a trailer manufacturer, purchased the division in 1934 with all patents, parts, and machinery, and he went into production using the Bungartz name.
The (Société Industrielle de Machines Agricoles Rotatives) of Switzerland began development of a similar machine and by 1932 was producing several machines ranging from to 10 horsepower, with a tilling width of 14" to 36", and weight from .
Starting after World War II, many countries in Europe started producing two-wheel tractors, most notably Italy. In 2014, Italy had over 15 manufacturers. Starting in the late 1960s and early 1970s, many European two-wheel tractors underwent an "evolution" which sharply contrasted them from the Asian and American machines: The introduction of fully reversible handlebars, allowed the machine's PTO (Power Take Off, where implements are mounted) to be effectively in the front or rear of the tractor, depending on handlebar position. This allowed much safer and more practical operation. Only very recently (since 2005) have any Asian manufacturers added this feature to their machines at all, and the bulk of Asian machines are still produced without this feature. Some two wheel drive tractors can be paired, through the PTO, with a drive axle on trailing equipment, creating a four-wheel drive arrangement for severe conditions.
In France, Somua, a company set up in the mid to late 1800s for making military equipment and later buses and even three wheel tractors, began making "motorculteurs" from the late 1920s till after World War II.
Other manufacturers now out of business were Energic and Labor.
Staub appeared to start making motorculteurs from about 1938 and still in production today. The first rototiller was the PP3. Later there was a PP4.
United States
Two-wheel tractors existed in the U.S. at least as early as 1913, when the Detroit Tractor Company advertised a tractor whose operator, riding on the implement, controlled the tractor via reins, just as he would a horse team. By 1918, the Moline Plow Company's Moline Universal Tractor likewise relied on its implement to supply the rear wheels in a four-wheel articulated unit, though its design dispensed with the long trailer tongue and horse reins. A 1918 example of Moline advertising called the Universal "the original two-wheel tractor", which was a fanciful claim in light of the Detroit Tractor and other machinery described with that phrase from 1913 through 1915. But Moline Plow no doubt felt pressured to claim priority in response to a very similarly built competitor, the Allis-Chalmers Model 6-12, which Moline Plow alleged was a patent-infringing copy.
E.R. Beeman invented the Gas Garden tractor, two wheeled walk behind model, in 190_. He had been a V.P. at Moline Plow Company prior to his invention. The BEEMAN Tractor Co. was located in Minneapolis, Minnesota. Previous to inventing Gas Garden Tractor, Mr. Beeman invented the Gas Garage door opener.https://oldpathsequipment.com/2013/02/beeman-tractors-designed-for-market-farms/ (August, 1918, issue of "Tractor World" magazine) "The Beeman tractor represents the development work of four years, not of unknown or inexperienced inventors or manufacturers, but of men who have worked under the direction of E. R. Beeman, formerly vice president and manager of the Monitor Drill branch of the Moline Plow Co. He was assisted by skilled and experienced tractor men in the experimental work and manufacturing, both in the shops and the field. Statement is made that the tractor as produced for commercial distribution is mechanically correct, the engineering principles have been proven, and the machines are built of high grade material." As early as 1911, Benjamin Franklin Gravely of Charleston West Virginia began with connecting the Indian motorcycle to a manually operated push plow. In 1916 he incorporated and, after obtaining partners, began producing single-wheel tractors and attachments under the name Gravely Tractor. The Model "D" Gravely Power Plow, like the prototype, was a single-wheeled affair, with a air-cooled engine. It wasn't until 1937 that Gravely would introduce the Model L two-wheeled tractor with a engine. Through the 20th century, Gravely became arguably one of the most successful and recognizable two-wheeled tractors produced in the United States, at one point offering 120 individual attachments for their all-gear drive machines.
In 1915, Rush Hamilton of Healdsville, California, designed grouser drive wheels for his tractor, which came with an articulated two-iron-wheeled sulky to which wagons or plows could be attached. It was about this time that he formed the Hamilton Tractor Company. About 10 years later, the wheels were called "Hamilton wheels" when used on a Fordson tractor. In 1916 he helped form the Fageol Motors Company, where he assisted in the development of the Fageol tractor.