Industry News

As early as 350 BC, the ancient Greek philosopher Aristotle recorded gears in literature. Around 250 BC, mathematician Archimedes also described in literature the use of a worm gear winch. In the present-day Katsifen ruins in Iraq, there are still preserved BC gears.

Gears have a long and rich history in China. According to historical records, gears were already in use in ancient China as early as 400-200 BC. The bronze gears unearthed in Shanxi, China, are the oldest gears discovered to date. As a guide to reflecting ancient scientific and technological achievements, the chariot is a mechanical device with a gear mechanism as its core. During the Italian Renaissance in the second half of the 15th century, the famous polymath Leonardo da Vinci Da Vinci not only made indelible contributions in the field of culture and art, but also in the history of gear technology. After more than 500 years, the current gear still retains the prototype of the sketch from that time.

It was not until the end of the 17th century that people began to study the shape of gear teeth that could correctly transmit motion. In the 18th century, after the European Industrial Revolution, the application of gear transmission became increasingly widespread; Firstly, the development of cycloidal gears followed by involute gears, and by the early 20th century, involute gears had gained an advantage in applications. Subsequently, variable gears, circular arc gears, bevel gears, helical gears, and so on were developed.

Modern gear technology has reached: gear module 0.004-100 millimeters; Gear diameter ranges from 1 millimeter to 150 meters; The transmission power can reach 100000 kilowatts; The speed can reach 100000 revolutions per minute; The highest circular speed reaches 300 meters per second.

Internationally, power transmission gear devices are developing in the direction of miniaturization, high-speed, and standardization. The application of special gears, the development of planetary gear devices, and the research and development of low vibration and low-noise gear devices are some characteristics of gear design.

3. Gears are generally divided into three categories

There are many types of gears, and the most common classification method is based on the gear axis. It is generally divided into three types: parallel axis, intersecting axis, and staggered axis.

1) Parallel axis gears: including spur gears, helical gears, internal gears, racks, and helical gears.

2) Intersecting shaft gears: including spur bevel gears, bevel bevel gears, zero degree bevel gears, etc.

3) Interlocking shaft gears: There are interlocking shaft helical gears, worm gears, hyperbolic gears, etc.

The efficiency listed in the table above is the transmission efficiency, excluding losses such as bearings and mixing lubrication. The meshing of gear pairs with parallel and intersecting axes is basically rolling, and the relative sliding is very small, so the efficiency is high. Interlocking shaft gear pairs such as helical gears and worm gears generate rotation through relative sliding to achieve power transmission, so the influence of friction is very significant, resulting in a decrease in transmission efficiency compared to other gears. The efficiency of gears refers to the transmission efficiency of gears under normal assembly conditions. If the installation is incorrect, especially when the assembly distance of the bevel gear is incorrect, resulting in errors in the same cone intersection point, its efficiency will significantly decrease.