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One, the origin of the lock -- wood lock

The earliest locks in the world came from Chinese wooden locks or wooden structure locks. In the past 5000 years, early wooden locks have been found in Yangshao culture ruins. The cycle has been written about the log lock and key. Early wooden locks are simple in structure, heavy in shape, colorful and easy to open with keys like bamboo sticks. The spring and Autumn period, the real class (Luban) improved, confidentiality is enhanced, and start making use of copper. In the folk, the wood locks have been used in the Ming and Qing Dynasties.

Two, the leaps of the lock -- three reed locks

Because wooden locks are not strong enough, but later they are made of bronze, but their structures are simple. In the Han Dynasty, a copper reed structural lock was commonly seen. It was commonly called three spring lock or reed lock, and the elastic force of two or three pieces of plate copper was used to achieve the function of closing and opening. Because the reed device can do a variety of changes, and can use the shape of key holes to determine the pattern of the key, safety performance, secrecy more than wood lock is a big step, and the scope of use is more extensive, so there is a wide lock. Since the Tang Dynasty, this kind of lock has been continuously improved and developed in the first century in 50s. There are more than 120 different styles. Some special techniques such as dark door, directional, two open, no key and text cipher have been used, which greatly increase the secrecy of the lock.

Three. Modern lock - car lock

In the eighth Century A.D., the eastern Romans made the original leaf lock, also known as the keyhole lock, and used key teeth to move the leaf gap in the lock to switch. In eighteenth Century, the British man, Dennis Potter, invented a cam switch lock. The metal blade in the lock was controlled by the spring. The key inserted in the lock must first turn the blade to open the lock. In nineteenth Century, European manufacturers invented a high - level cam - switch lock, the key's tooth flower increased to 1600, and the subsequent improvements made the key tooth flower up to thousands of changes. The key to the lock of the blade is beautiful and elegant. It is recognized as the standard of locks and keys. Many countries make large gold keys and give them to friends and VIPs to symbolize respect, peace and friendship. I started producing leaf locks from Qing Dynasty, and I was gradually replaced by elastic lock after 1930s. After the founding of new China, many enterprises still produce iron padlock with leaf structure.

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