History of ancient machinery in China.

History of ancient machinery in China.

China is one of the countries with the earliest mechanical development in the world. There were many mechanical inventions in ancient China, each with its own characteristics in the utilization of power and the design of mechanical structure. The design and application of many special machinery, such as south guide car, seismograph and incense burner in quilt (see color map [Yin incense burner in Tang Dynasty, 1963 Xi unearthed in Anshapo village. The hemispherical incense burner is made by gravity (no matter how I roll and rotate the spherical shell, the mouth of the burner is always in a horizontal state), which is unique. The ancient metal smelting and casting technology was invented earlier and the technology was exquisite. For example, the Shang and Zhou bronzes are simple and vigorous, and the Spring and Autumn bronzes are slender and exquisite, forming a unique style of ancient Chinese bronzes. The earliest bronzes discovered in China, such as the copper knife unearthed in Majiayao, Dongxiang, Gansu, have been around 4800 years ago.

Before the Spring and Autumn Period (before 770 BC), about 400,000-500,000 years ago, primitive tools such as scraper, chopping tool and triangular tip tool appeared in China. Grinding technology appeared 40,000 to 50,000 years ago. Many stone tools have been smooth and sharp, with single edge, double edge, convex edge, concave edge and round edge. Bow and arrow appeared 28,000 years ago and was the earliest invention in machinery. From 8000 BC to 2800 BC, a pottery wheel (pottery turntable) appeared. Agricultural tools appeared in about 6000 ~ 5000 BC. Besides stone axes and knives, there are also stone hoes, shovels, stone sickles, mussels, bone sickles and bones. Stone axes and knives have been polished with hard sand.

Around the Xia Dynasty, there were non-spoke wheels and various spoke wheels. There were quite exquisite two-wheeled vehicles in the Shang and Western Zhou Dynasties (see ancient vehicles in China). Canoes, rafts and other water vehicles have long appeared. In the late Neolithic period, people were able to cast simple tools and weapons with stone models and clay models. During Shang and Yin Dynasties, with the development of handicraft production and the improvement of technical level, a splendid bronze culture was formed. The bronze smelting and casting technology has been highly developed (see China Ancient Bronze Metallurgical and Casting Technology). Fang Ding, a bronze casting company, weighs 875 kilograms, and the bronze casting Ceng Houyi Zunpan in the Spring and Autumn Period has been very fine. The period from the Spring and Autumn Period to the Han and Wei Dynasties (770 BC-265 AD) was the period when ancient Chinese machinery began to develop rapidly.

In the Spring and Autumn Period, the smelting and casting technology of iron and pig iron (see China ancient cast iron technology) began to appear. The appearance of black core malleable cast iron, white core malleable cast iron and forged steel has accelerated the transition from bronze to iron. After the mid-Spring and Autumn Period, lost wax casting and low melting point alloy casting and welding technology were invented. During the Warring States period, there were processes such as stack casting and anchor chain casting. Gray cast iron was smelted in the middle of the Western Han Dynasty, and thin-walled iron castings with a wall thickness of 3 ~ 5 mm appeared. The heat treatment technology of cast iron has also developed.

Crossbows appeared in the Spring and Autumn Period, and the crossbow machine for controlling shooting is a relatively dexterous mechanical device. By the Han Dynasty, the machining accuracy and surface smoothness of crossbow machine had reached a fairly high level. Han crossbow has eight specifications: 1 stone to1stone. The formation of these norms marked the initial establishment of mechanical manufacturing standards in the Han Dynasty. The names of workers, forgers and grinders are left on the crossbow machine (see bow and crossbow).

Kao Gong Ji, circulated during the Warring States Period, is the earliest extant handicraft monograph, which records the manufacturing technology of wheels. The elasticity of bow, the firing rate of arrow and the stability of flight are deeply explored.

There were various types of warships and a large number of three-story and four-story cabins in the Han Dynasty. Some ships have been equipped with stern rudder and efficient propulsion tools. During the Western Han Dynasty, the incense burner in the quilt was exquisitely constructed. No matter how the spherical incense burner rolls, the hemispherical furnace body in its center always remains horizontal.