Pin and tumbler locks are the ones that you’re most likely to find on doors in the U.S. In fact, 90% of all U.S homes are protected by pin and tumbler locks. The original design of this lock consisted of a series of single pins. When these were locked, they kept the bolt from moving by being pushed into the bolt itself. The key was used to lift the pins out of the bot, allowing the bolt to move freely. This was the first instance of a shear line, folks! This major discovery paved the way for modern locks. Early locks we’re made out of wood, but metal soon became the material of choice. Brass locks followed, and then the use of iron. The Yale Company modified the pin and tumbler lock, making it smaller and better at its job. The lock hasn’t changed much in its core design since then, but different add-on’s to the method have been applied in modern locks. Features like sidebars, ball bearings, hardened steel and security pins are auxiliary components that enhance modern lock security.
Pin tumblers are tacks in a lock that are pushed down by a spring. In order to separate the pins from the shear line, each pin must be raised to a specific level. Once the pins are freed from the tumbler, the lock is open and can be manipulated freely. From there you can lock or unlock the bolt inside. The edge of the blade in traditional pin and tumbler locks are the bitting area. There have been a few small changes to the internal components of pin and tumbler locks over time, but the base design and function remains intact. Newer designs like axial//tubular locks and dimple locks offer better security than their traditional counterparts. A key that is not designed to match the biting in a pin and tumbler lock will not be able to move the bolt.