A tubular pin tumbler lock, also known as Ace lock or "axial pin tumbler lock" or "radial lock", is a variety of pin tumbler lock in which the pins are arranged in a circular pattern, and the corresponding key is tubular or cylindrical in shape.

J.A. Blake is credited with patenting the first tubular lock in 1833. Walter R. Schlage continued the development of the tubular lock. He was awarded 11 patents, and his improvements made the tubular lock what it is today.

Tubular locks are commonly seen on bicycle locks, computer locks, and a variety of coin-operated devices such as vending machines and coin-operated washing machines.

Design

Security

Tubular pin tumbler locks are generally considered to be safer and more resistant to picking than standard locks, though there are several ways to open them without a key. Such locks can be picked by a special tubular lock pick with a minimum of effort in no time; it is also possible to defeat them by drilling with a special “hole saw” drill bit. Standard tubular lock drill bit sizes are .375" (9.53 mm) diameter and .394" (10 mm) diameter.^* To prevent drilling, many tubular locks have a middle pin made of hardened steel, or contain a ball bearing in the middle pin.

A 2004 internet post by Chris Brennan revealed that certain Kryptonite locks using a tubular pin configuration could be opened with nothing more than a slightly-modified BIC ballpoint pen. ^*

Locks

Serrure tubulaire