How does a combination lock work? Why is it considered more secure than the cylinder lock?

We all want our valuable possessions to be kept in safe spots, locked away from any potential harm or theft. One basic way of securing such assets is by locking them up.

Now, there are several kinds of locks such as padlocks, knob locks, rim locks, etc. But in this piece of information, we will be comparing the combination lock versus the cylinder lock and conclude which of these is more secure for you to use.

A combination lock is activated by twisting a dial, pushing buttons, or manipulating a row of movable numbers, such as in a suitcase. Whatever the form, the operating principle is the same. All such locks open with the entering of a correct sequence of numbers which have either been set by the manufacturer or changed by the owner. The type of lock used as a padlock for doors and bikes is a good example to explain the internal working. It has a series of notched wheels with a looped metal bar running through them. The bar has as many bumps as the wheels, but until the notches catch onto these protrusions, the bar remains restrained and cannot slide out. The lock opens only when the proper sequence of numbers is selected, and wheels are turned accordingly.

A more complex dial-type combination lock is used for safe or other highly secure containers. There is a numbered dial that is turned to achieve the particular combination of numbers. Behind the dial, there are usually three wheels and each turns according to its respective number when the dial is moved. When the first number is set, a metal pin attached to it turns the first wheel. The metal pin fits through the notch of the wheel. This wheel does not move in subsequent operations. The second number dial aligns the slot of the middle wheel with that of the first and, finally, the third wheel’s slot is aligned, and the bolt then is released.

A cylinder lock, however, functions through the use of a metal key. These locks have a distinguishing feature which is a cylindrical shaped deadbolt in the center of the doorknob. This lock would open only when the designated metallic key is entered into the given slot. Many cylindrical locks have the option of locking from the inside and also the outside, with both sides having keys for unlocking the bolt. Otherwise, there may also be locks that have a button on one end that can be used to lock or unlock.

The cylinder lock is shaped literally like a cylinder which is attached to a cam. A slot is provided on the lock for inserting the key. When one inserts a key in a cylinder lock and turns, the cylinder rotates an attached cam which either pulls or pushes the bolt. If you turn the key one way, the cam pulls on the bolt and the lock opens. If you turn it the other way, the cam pushes the bolt which closes the lock. The function of a cylindrical lock is fairly simple which makes it easily breakable.

The cylinder lock is known to be used for very low-security purposes such as locking offices or storerooms. Keeping highly prized assets within the security of a cylindrical lock is a bad idea. It is because such locks are highly manipulative and can be easily broken through the use of pliers or a pipe wrench. Important items kept inside a room with a cylinder lock may need to be further stored in a safe with higher security.

The combination locks are among the most secure. If the dial has 100 numbers on it, then there are 100 possible positions of alignment for each of the three wheels—and a total of one million possible combinations for the lock. The addition of a fourth ring or wheel will increase this by a factor of 100 and make it impossible for anyone to discover the combinations of locks. The numbers can easily be changed, and there are innumerable variations today in the basic designs of combination locks.

The kind of lock you choose for your functionality depends on the level of security you wish to achieve. So, for example, you own some very rare artefact which is extremely valuable, and you need to keep it safe, the right option to choose would be a safe with a combination lock.