As the largest mining machine in the world, electric shovel has undergone a long development process. The early excavation and construction of mankind depended mainly on manpower, and some primitive excavating tools emerged. In the late fifteenth Century, a group of engineers in Siena, Italy, designed a dredger based dredger. Da Finch improved the design on this basis. The dredger has a ten type winch with a wooden structure on the side side, with a bucket at the end, with a capacity of about 0.2 cubic meters. The handle of the winch is pushed by manpower to drive the bucket work. This can be said to be the embryonic form of a multi bucket excavator. But before the steam engine appeared, the excavating equipment was still driven by manpower.
In 1679, the French Denis Papin invented the steam cooker with high pressure. He used a steam in a high pressure cooker to push a piston in a cylinder, thereby creating a simple steam engine. But Papin's invention did not actually apply to industrial production. In 1698, the British man Thomas Savery (Thomas Savery) invented the non piston steam pump, using the steam pressure difference to extract mine water, but the efficiency was very low. In 1712, Scotland blacksmith Thomas Neen (Thomas Newcomen) produced a piston type steam engine capable of 10 reciprocating movements per minute. The steam engine began pumping in mines in the United Kingdom, France and Germany. Thus Europe entered the early stage of the industrial revolution.
In 1763, Watt, the British man, began to improve the steam engine, and developed a separate condenser, adjustable valve, cylinder insulation, planetary gear, parallel linkage mechanism, centrifugal governor, pressure gauge and other components, and made the first prototype in 1769, which was more than 5 times higher than the new steam engine. . After the invention of Watt steam engine, it was rapidly promoted and applied. In 1769, French Frenchman became the world's first three wheeled steam car. In 1804, British Richard Trevithick made the world's first steam train. In 1807, American Fulton invented the steamship. In September 27, 1825, the world's first railway was opened between Stockton and Darlington in England, and the total length was 21 km, so European countries began to build railways. In May 24, 1830, the railway from Baltimore to Ohio was the first railway in the United States, followed by the rapid expansion of the railway construction in the eastern states of the United States, which led to the demand for earthwork machinery.
In 1833, William Otis, a railway engineering contractor in Philadelphia, United States, began developing a steam powered excavator powered by Otis. In 1835, the first steam driven single bucket excavator was successfully constructed. The excavator uses half revolving, rail line, iron wood mixed structure, mast big arm structure similar to crane, bucket rod mounted on the big arm, dug bucket on the bucket. The steam driven winch drives the lifting bucket of the chain and the pulley, and the gear for the telescopic bucket is driven by a chain. There is one person on either side of the machine, and the rope is used to pull the rotation of the big arm, and at the same time, it is also responsible for operating the bucket door latch. The whole set of excavators, including steam boilers, was placed on the four - wheel railway flat, with a hoist single bucket excavator in front of a steam locomotive. The excavator can excavate the belt through the continuous extension of the rail. The excavation of the excavator is about 35 m cubic meters per hour, which is more suitable for the construction of railway engineering. Therefore, people call it the railway shovel (steam shovel).
There is no doubt that this is a great invention. At that time, China was still in the Daoguang year, and the United States had not yet developed the western part of the country, and the South still used a lot of black slaves. Until the early twentieth Century, before the advent of bulldozers and scrapers, earthmoving machinery referred to as steam shovels. For the first time, it used machines to excavate earthwork, though not perfect. But from the point of view of the history of the machinery industry, it has established a model, and the giant shovels, which are all powerful in the world's large open-air mines, still use the basic form of Otis's steam shovel.
