1. What is a gear?
A gear is a toothed mechanical part that can engage with each other.It is widely used in mechanical transmission and the whole mechanical field.
2. The history of gears
As early as 350 BC, the famous ancient Greek philosopher Aristotle recorded gears in his documents.Around 250 BC, the mathematician Archimedes also described in his writings a winch that used a turbo worm.Among the ruins of what is now caitspen in Iraq are the gears of B.C.
Gears also have a long history in China.According to historical records, as far back as 400 to 200 BC in ancient China began to use gear, the bronze gear unearthed in China's Shanxi Province is the oldest found so far, as a reflection of the ancient scientific and technological achievements of the south-pointing cart is the gear mechanism as the core of the mechanical device.During the Italian Renaissance in the second half of the 15th century, the famous versatile leonardo Da Vinci not only left indelible contributions in the cultural and artistic aspects, but also in the history of gear technology. After more than 500 years, the gear still retains the original sketch.
It was not until the late 17th century that people began to study the shape of the teeth that could transmit motion correctly.In the 18th century, after the industrial revolution in Europe, the use of gear drive became more and more widespread;First the cycloid gear was developed, then the involute gear, until the early 20th century, the involute gear in the application of the advantage.Then developed the displacement gear, circular - arc gear, bevel gear, helical gear and so on.
Modern gear technology has reached: gear modulus 0.004~100 mm;The diameter of the gear ranges from 1 mm to 150 m;Transmission power up to 100,000 kw;Speed up to 100,000 RPM;The highest circumferential velocity is 300 m/s.
Internationally, power transmission gear is developing along the direction of miniaturization, high speed and standardization.The application of special gear, the development of planetary gear, the development of low vibration and low noise gear are some characteristics of gear design.