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Padlock

technology Maturity 11-13 Next article →

A padlock is a portable tool used to keep things safe.

Padlock klódka ubt
Padlock klódka ubt

It stops theft, harm, or vandalism by securing an opening. You might see one used on a chain link or a door hasp.

- Padlock -
- Padlock -

Most padlocks have a U-shaped metal loop called a shackle. This shackle can either swing away or slide out of the body. The lock works by using a mechanism to hold that shackle in place.

Double Ball Cutaway Padlock (open)
Double Ball Cutaway Padlock (open)

This keeps the loop from moving so the object stays shut.

There are different ways these locks work step by step. Some use an integrated mechanism where the parts touch the shackle directly. For example, a "Scandinavian" style lock uses rotating disks. A key turns each disk until notches on their edges line up. Once they line up, the shackle can slide out of the body. Other locks use a modular mechanism. In these, a key turns a plug inside a cylinder. This moves a "locking dog," like a ball bearing, to let the shackle move.

bilock
bilock

People have been making padlocks for a very long time. Some examples date back to the Roman Era between 500 BC and 300 AD. Merchants used them while traveling old trade routes to Asia. In China, padlocks were used during the late Eastern Han dynasty.

Padlock 4 combination
Padlock 4 combination

Early Chinese locks were often made of bronze. They sometimes used splitting springs or even letter combinations. In England, Viking settlements in York had locks from 850 AD. These used spring tine mechanisms to stay secure.

Many famous inventors changed how locks were built. Christopher Polhem invented the "Scandinavian" lock in Sweden. This design was so good that a company in New Jersey made them until the 1950s. In 1871, the McWilliams company received a patent for these locks. Later, Yale & Towne patented a design in 1877 with a special "cartridge." This allowed people to change the keys easily. In 1920, Harry Soref started Master Lock using laminated plates.

Steel Cable Padlock
Steel Cable Padlock

These plates were stacked and riveted together to make a strong, low-cost lock.

Today, we use many different kinds of padlocks in our lives. Some are electronic and use a fingerprint or a phone to open.

Passive electronic padlock with key
Passive electronic padlock with key

Others use a flexible steel cable to wrap around a bicycle. We even see the idea of a padlock on the internet. A small lock icon on a web browser shows that data is secure. Some people even use physical locks to show love. They attach them to bridges or monuments to show their feelings are permanent.

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🖼️ Images & Media (7)
File:Padlock klódka ubt.JPG
Padlock klódka ubt.JPG
File:- Padlock -.jpg
- Padlock -.jpg
File:Double Ball Cutaway Padlock (open).jpg
Double Ball Cutaway Padlock (open).jpg
File:Padlock 4 combination.JPG
Padlock 4 combination.JPG
File:Passive electronic padlock with key.jpg
Passive electronic padlock with key.jpg
File:Steel Cable Padlock.jpg
Steel Cable Padlock.jpg
File:bilock.JPG
bilock.JPG
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