When we match a key and try to unlock it, it may not be possible to unlock it smoothly every time. We can twist the key left and right with a little force, or twist it while shaking up and down, you can also pull out the key and screw it again.
If the key handle can be unlocked by pressing down, it may be that the key tooth file inside is a little deeper;
If the key handle can be unlocked by lifting it up, it may be that the key tooth file outside * is deep;
If the whole key can be unlocked by lifting it up with its flat end, it may be that the whole key tooth has been filed deeply;
If the key extraction point can unlock the lock, it is'Shoulder'More files;
For those key teeth with more files or'Shoulder'
You can use the method of stamping to extend it and correct it, or re-match it with a key;
If you twist the key hard to unlock the lock, but it is not flexible to turn the lock cylinder, it may be that a tooth of the key is a little higher, we can pull out the key to observe the indentation on the key tooth, the indentation can be slightly corrected with a fine file. When observing the indentation, the key teeth can be turned back and forth against the light, so that those tiny indentations can be more easily observed, the following will further explain how to generate indentation when talking about the hidden matching of bullet locks.
In ancient times, the original style of the lock was only the rope and knot used to bind the items to show the owner's possession of the items.
In the famous ancient Greek legend, Alexander, the Prince of the King of Macedonia, invaded the Arabian Peninsula and occupied gerdiao.
There is an ancient chariot placed in some shrines in the center of the city's streets, on which is the famous'Geldios knot'
According to legend, the person who untied the knot was the ruler of Asia. Alexander couldn't untie it.
Finally, he pulled out his sword and cut the knot into two breaks with one sword in Alexander's way.
It is hard to say whether Alexander's way really opened the knot, but today's car thieves, facing the solid steering wheel lock, simply saw the steering wheel with a saw, would they think that their ancestors, how could it be Alexander at the time of his reign?
However, the origin of locks did not start from Alexander's kingdom.
Experts from all over the world generally believe that there are two starting centers for locks: one is the Mesopotamia and Egypt, and the other is Greece, Rome and even the whole Western Europe, to the British Isles and then to the United States;
Another center is China, which was introduced to North Korea, East Japan and South Vietnam.
All these changes took place after human beings had rooms and doors.
At first, only crude wooden bolts limited the door--
It gradually evolved into a stronger metal lock bolt. In order to insert them into the lock and fix them, clockwork and Reed are used in the mechanism--
The structural positions of these devices were changed, and various types of locks were born. In order to open them, we need specific keys.
Various early mechanical locking devices were created on the basis of various mechanical principles.
The function of the key is to make the locking mechanism in the lock change accordingly, when unlocking (Decoding)
In the process of, only when the key code and the lock code are identified and confirmed by the mechanism, the lock bolt and the lock tongue can be activated through the transmission parts to release the lock and decode smoothly.
The safety performance of the mechanical lock depends on two mechanical principles. One is to rely on the obstacles fixed in the lock to prevent the fake key from entering and rotating, and the second is to use one or more movable limiting objects, installed in the lock, the key determines whether it is in the previously scheduled opening position. The more the number, the more complex the code, and the safety performance will be improved accordingly.