Pin Tumbler Locks

What Are Pin Tumbler Locks?

A pin tumbler lock is a type of lock in which a number of pins are arranged in a circular pattern, and the corresponding key is tubular or cylindrical in shape. It is a cylinder based lock design that uses movable pins to prevent rotation of the plug. Basically, the pin tumbler lock is a lock mechanism that uses pins of varying lengths to prevent the lock from opening without the correct key. A key is used to properly elevate pins to allow the plug to rotate and the locking bolt to be retracted. Other names have been used for this unique and historic type of lock, including circle pin tumbler lock, radial lock, or Ace lock after its original manufacturer.

They are one of the most used locks worldwide, used in bicycle locks (such as the Kryptonite lock), Kensington computer locks, elevators, and a variety of coin-operated devices such as vending machines, and coin-operated washing machines. Tubular pin tumbler locks are generally considered to be safer and more resistant to picking than standard locks. They have become more popular than lever tumbler locks.

History of pin tumbler locks

Pin tumbler locks were first seen in the ruins of the Palace of Khorsabad in Iraq. The pin tumbler lock was invented in ancient Egypt some 4,000 years ago. They were initially made of wood, subsequently replaced by brass and metal. In 1805, the earliest patent for a double-acting pin tumbler lock was granted in England to American physician Abraham O. Stansbury based on the Egyptian design.

In 1800, Linus Yale Jr. and Linus Yale Sr. redesigned the pin tumbler with the idea of pin pairs. Linus Yale Jr continued the work of his father and made it smaller and more reliable. It is interesting to note that the lock has remained virtually unchanged since Linus Yale Jr.’s last design.

Over the centuries pin tumbler locks have come to be thinner, less cumbersome and safer locks.

How a pin tumbler lock works

Pin tumblers are a series of pin stacks pushed down by a spring. Once all pin stacks are separated the plug can freely rotate and actuate the locking bolt to lock or unlock the lock. Based on this mechanism, an incorrect key will not align all components correctly; rotation of the plug will be blocked at the shear-line.

Design

The lock has a cylindrical hole in which the plug lies. This plug must rotate before the lock can open.  The plug has a key way through which the key enters. The other end has a lever which allows a retracting bolt. A series of 6-8 holes are drilled vertically in the plug containing key pins. Driver pins are placed between the key pins and springs. The cam is an extension connected to the back of the plug which actuates the bolt mechanism to lock or unlock the lock.

Types of pin tumbler locks include cylinder locks (which include rim mounted, euro cylinders, key in knobset cylinders, Ingersoll format cylinder, American and Scandinavian round mortise cylinder, Scandinavian oval cylinder), and electronic/digital cylinder which work using electric current.

More information on the available design types currently in the market can be obtained from KC Worthing Locksmiths.

How secure are pin tumbler locks?

Pin tumbler locks are well protected against drilling and are highly resistant to severe weather conditions. They are however vulnerable to attacks such as lock picking, key bumping or pick guns, decoding, bypass and lock snapping.

How much do they cost?

Pin tumbler locks are cost effective. The price of lever tumbler locks varies widely depending on the particular design type and the number of levers. You can get a quote from KC Worthing Locksmiths.

If you need more information on installation, maintenance, repairs of pin tumbler locks as well as other different types of locks contact KC Worthing Locksmiths who offer all kinds of locks, and modern security services.