How do keys open doors?
Unlock the secrets of how these simple devices keep your possessions safe
Throughout history, numerous lock-and-key combinations have been used to keep rooms and valuables secure. The earliest lock comprised of a series of wooden pins that could be moved only by a key with a matching profile. Called a pin-lock, it formed the basis of today’s pin-tumbler lock (often called a Yale or radial lock). Inside the barrel of a pin-tumbler lock is a series of spring-loaded, two-part pins of varying length. When a small, flat-sided key is inserted into the barrel, the serrations along its edge push the pins up. If the key is the correct one for the lock, the pins will line up so that the bottom half of the pins sit perfectly inside the barrel. This enables the barrel to be turned (or tumbled) with the key, which opens the lock. Other keys may fit into the lock, but the lack of pin-alignment stops the barrel from turning. Not all keys are flat, though. Those that fit into warded locks – used widely during the Middle Ages – are cylindrical. Instead of pins, these locks use curved plates, or wards, to block incorrect keys from turning. Only those with matching ‘notches’ can rotate fully. This design led to the first skeleton keys – versions that had most of their notches filed down to avoid the wards. Many companies are now developing mechanical door locks that don’t need physical keys. They can be opened with the sound of your voice or a swipe of your smartphone – although most still allow you to use an old-fashioned key.
How keys work How Keys Open Locks Tip And Tricks
Take a look inside a pin-tumbler lock to understand how keys open doors
The end of lost keys?
A British insurance company estimated that the average person spends 3,680 hours – that’s 153 days – searching for misplaced items, mainly smartphones and keys. However, a gadget called Tile can dramatically reduce these wasted hours, helping you find your essential items quickly and easily. While it looks like a simple square of plastic, each Tile contains a Bluetooth tracking device. If you attach it to your valuables, it can transmit its location – in the form of radio waves – over short distances (around 30 meters), using very little power. Almost all smartphones have in-built Bluetooth, so by installing a dedicated app, they can wirelessly communicate with your Tiles. If you lose your keys, the app directs you to their location using sound. If you misplace your phone, you can ring it by pushing a button on one of your Tiles. It will play a tune even if it’s on silent!
Tile tags act like homing
beacons to help you track
down missing valuables