Throughout the world's industrial history, the source of modern mining machinery can be traced back to the silt excavators in the late fifteenth Century, in Siena, Italy, about 50 kilometers from the southern part of Florence. Because water shipping has been a very important mode of transportation in Italy, it is necessary to dredge the river regularly. According to the "Da Finch notes", the excavating ship is juxtaposed by two small boats. A water truck like wheel is set up between the side side, and the end of the four corner of the wheel is installed with a shovel. The bucket is driven by the revolving wheel by manpower, and the bucket is put into the bottom of the river to dig the silt. The bucket capacity is generally not over 0.2-0.3 cubic meters. When the silt laden bucket is rotated to the top, the mud will be dumped into the cabin through the slide plate. This should be the embryonic form of a multi bucket excavator. In 1712, the British man Thomas Neen (Thomas Newcomen) invented the piston type steam engine, which was improved by Watt, and was made into a watt type steam engine in 1769. Its energy efficiency is more than 5 times higher than that of the new steam engine. The extensive application of the steam engine has made the digging machine begin to change from manpower drive to mechanical drive.
In 1833-1835, William Otis (William Otis), a railway engineer in Philadelphia, designed and built the first hoist type single bucket excavator driven by a steam engine and mounted on a railway flat. It is used as a mixed structure of iron wood. The revolving arm of the crane is still traced by the human rope, and it is excavated through the continuous extension of the rail. Therefore, it is called the railway shovel (steam shovel). However, because of Otis's early death, patent protection and low labor cost, Otis type steam shovel has not been widely applied. Since 1870, the development of large-scale construction of railway and steam shovel in the United States entered the golden age, and its performance has been improved continuously. It began to be applied in the fields of railway construction, canal excavation, strip mining and so on. In 1910, the first motor driven steam shovel was developed in the United States, and tracked walking equipment was applied. In 1912, a full rotary steam shovel driven by gasoline engine and kerosene engine was introduced, and a steam shovel driven by diesel generators was introduced in 1916. In 1924, the direct drive of diesel engine began to be used on single bucket excavator. Since then, with the development of the automobile industry, the tire chassis has been gradually applied to small excavators. In 1940s, a suspension excavator equipped with hydraulic backhoe was installed on tractors.
The Second World War and the resumption of post war construction have greatly promoted the development of mining machinery. With the application of hydraulic technology, in 1951, the French Poclain (Pok) company launched the world's first full hydraulic excavator. Born in 1879, Georges Bataille, founder of the company, was founded in 1927 with engineer Anthony ledger, with the main business for repairing agricultural machinery and in 1930 the company was renamed as a manufacturing company. Since 1948, Pok has made small wheel excavators, with the number of employees increasing to 120. In October 1951, it developed the first hydraulic excavator, which used the wheel chassis modified by dodge 4x4, the front part of the car cab and the hydraulic excavator in the rear. The upper body is composed of a console, a hydraulic arm and a bucket, which revolve around the column above the rear axle of the chassis, and the volume of the square bucket is about 1 cubic meters.
In 1961, the company launched the TY45 wheeled hydraulic excavator, using a unique top three wheel chassis with a total power of 48 horsepower and a weight of 10 tons, which sold 30 thousand units in 1982. In 1974, the company's excavator business was merged by Keith group, retaining only the business of hydraulic components. Keith, founded in 1842, is the world's first enterprise to produce steam machine threshing machines, and began producing steam rollers, graders and other 名媛直播 in 1912. In 1957, chase bought the American Tractor Company in Indiana, when the company had developed a crawler type hydraulic excavator.
The hydraulic excavators in the initial trial production mostly use the hydraulic technology of aircraft and machine tools, lack of hydraulic components suitable for various working conditions of excavators, the quality of manufacturing is not stable enough, and the supporting parts are not complete. Since 1960s, hydraulic excavators have entered the stage of popularization and vigorous development, and the number of excavator manufacturers and varieties has increased rapidly, and output has increased rapidly. By the beginning of 70s, hydraulic excavators accounted for 83% of the total output of excavators, and gradually replaced mechanical excavations. The weight of the whole machine is below 50 tons, and the bucket capacity is below 4 cubic meters.
