Ask about the development history of tractors in China.

Since ancient times, many people have tried to use mechanical power instead of human and animal power for farming. But it was not until19th century that Europe entered the steam engine era that the birth of power agricultural machinery became possible. In 1930s, 65438+2009, people began to study the use of steam trucks to pull agricultural machinery for field work. However, the steam engine tractor (the predecessor of steam tractor) that could be built at that time was like a water locomotive. Even if you are not trapped in the ground, the soil will be so hard that it is impossible to cultivate. 185 1 year, Fallas and Smith in England used steam engines to realize mechanized farming of farmland for the first time. Some people regard this as the beginning of agricultural mechanization, but at that time, their method was to put the steam engine at the head of the field and pull the plough share far away with wire rope. Later, with the development of steam engine manufacturing technology, a miniaturized steam engine appeared, which was installed on the chassis of the vehicle to drive the wheels, so that agricultural machinery could be directly driven from the field, which led to the birth of tractors. Alabat of France and R.C. Parvin of Illinois invented the earliest steam-powered tractors in 1856 and 1873 respectively. The tractor at that time was very similar to the early steam engine, but it had more horsepower and slower speed.

The original tractor was bulky, expensive and inconvenient to use, and often needed several people to operate. They are suitable for farming in the vast Yuan Ye, which is difficult for ordinary individual farmers to afford. 1889, Chad engine company in Chicago, USA, manufactured the world's first agricultural tractor using gasoline internal combustion engine-Bajia tractor. Because of its portability, convenient operation and high efficiency, the appearance of internal combustion engine laid the foundation for the popularization and application of tractors. At the beginning of the 20th century, Sweden, Germany, Hungary, Britain and other countries almost simultaneously produced tractors powered by diesel internal combustion engines. During the First World War, due to the war, the shortage of labor and the rising price of agricultural products promoted the development of agricultural tractors. During the period of1910-1920, the tractor driven by steam engine and the tractor driven by internal combustion engine launched fierce competition, and the latter showed greater superiority and gradually eliminated the former. Today's tractors use diesel internal combustion engines.

Tractors are divided into wheeled and crawler types. The earliest tractors used iron wheels, which were not only heavy and easy to get stuck, but also often crushed the roots of plants. As early as the 1930s, shortly after the birth of steam cars, it was envisaged to install "tracks" made of wood and rubber on the wheels of cars, so that heavy-duty steam cars could walk on soft soil. However, the performance and use effect of the early tracks were not good until 19065438. Three years later, Holt, an engineer from California, applied Lumbard's invention to design and manufacture the "77" steam tractor. This is the first crawler tractor in the world. 1904165438+1October 24th, this tractor was tested for the first time and then put into mass production. 1906, the tractor manufacturing company founded by Holt produced the world's earliest crawler tractor powered by gasoline internal combustion engine. This tractor began mass production the following year, and it was the most successful tractor at that time. A few years later, it became the prototype of the first tank developed by Britain in the world.

In the development of wheeled tractors, people initially widened the steel wheels to increase the landing area and reduce the pressure, but the effect was not good. Later, they came up with a method of adding a rubber protective layer to the steel wheel. After the birth of automobile tires, people used solid and pneumatic tires for tractors. However, automobile tires are not completely suitable for tractors. First, the grooves of automobile tires are too shallow and thin. Secondly, it is found that the tractor's driving performance on soft ground is better when the tire is under-inflated than when the tire is fully inflated. 1932 American Fils Dang tire rubber company produced large-size high-pattern low-pressure pneumatic rubber tires. This is the first tire really suitable for agricultural tractors, which greatly improves the driving and traction performance of wheeled tractors.

By the end of 1940s, tractors had replaced livestock as the main power of farms in North America, Western Europe and Australia. Since then, tractors have been widely used in Eastern Europe, Asia, South America and Africa.