What is the “Berlin lock” that locks through the door with a rare “key without handle”?
A typical key consists of a key blade part that is inserted into the keyhole and a handle part that is pinched by hand. However, the key of the “ Berlin lock ”, which was invented in Germany more than 100 years ago, is known for its unusual shape with blades at both ends .
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You can see exactly what the Berlin lock is actually by looking at the following movie that actually locks the door.
The actual Berlin lock looks like this, and both ends of the metal bar are blades.
A normal key can pass the hole in the handle through the key ring, but the key of the Berlin lock cannot be fixed to the key ring because there is no handle. Then, the device which hangs to the key holder is done by hooking the blade to the cylindrical part attached to the key ring.
The blades at both ends have the same shape, and either can be locked or unlocked. Insert one end of the key into the keyhole ...
When I turned the key instead of holding the blade, it was unlocked.
Looking at the other side of the door, you can see that the keyhole is shaped like a katakana “fu”.
A key sticked out of the keyhole to penetrate the door.
Go outside, close the door and turn the key.
If you remove the key, the door will be locked.
The Berlin lock was invented in 1912 by Johannes Schweiger, a locksmith in Berlin. Berlin locks have the effect of ' preventing forgetting to lock' because they must be locked in order to remove the key, and have been installed in more than 20,000 houses mainly in Berlin. In addition, it was reported that the parts that fix the key of the Berlin lock were invented so that even a drunk person could safely carry the key and take it out easily.
However, because Berlin was divided during the Cold War following the Second World War, it was difficult to receive Berlin locks in some areas of Berlin. In addition, the locking technology has evolved, and safer locks have been made, so it seems that the Berlin lock has not been newly installed.
Nonetheless, Berliner Mieterverein, a political party dealing with housing issues in Berlin, reports that “as of 2005 we have confirmed that 8,000 to 10,000 Berlin locks have been used in Berlin”.