How Does a Key Work?
Something so easy and with such a simple mechanism has the ability to lock and unlock anything and everything and yet, we still rely on it. This is because the mechanism is not as simple as it looks and takes great precision and has a tremendous amount of attention to detail involved.
Keys may be small, but they have many individual parts to them. What’s truly unique is that all these elements must be absolutely precise. Or else, the key won’t fit and the lock won’t open. And that’s when frustration sets in. There are five parts which make up a typical key which you would use in your home or office:
- Bow (or more commonly called the “Head”): This is the part of the key which sticks out once it’s placed in the door lock (in other words, it’s the part which you hold and turn).
- Shoulder: This part of the key prevents it from going any further into the lock.
- Blade: The long, slender part of the key which actually makes its way into the lock.
- Cuts: Along the blade, you’ll notice little jagged pieces running along it. Those are called cuts.
- Tip: The pointy end of the key.
The cuts which are along the blade of the key are designed to align perfectly with the key’s lock. Inside the lock are spring-loaded mechanisms called pins. When the correct key slides into a lock, the pointed cuts on the blade allow the pins to move up and down until they are lined up along a track that’s called a shear line.
When all the pins are synchronized with the shear line, they can turn and the lock will open. Ever notice that sometimes a key will fit perfectly into a lock, only to not have it open? That’s because one of the pins inside won’t line up with the shear line. This will prevent the lock from turning — and ultimately opening.
