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Padlock

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A padlock is a portable security device designed to prevent theft, vandalism, or harm.

Padlock klódka ubt
Padlock klódka ubt

It functions by securing an opening, such as a hasp staple or a chain link, with a metal loop. This loop is called a shackle.

- Padlock -
- Padlock -

Most shackles are U-shaped and are made of metal with either a round or square cross-section. Depending on the design, the shackle might swing away from the body or slide out of it when the lock is opened. Padlocks are essential tools for protecting property in many different environments.

To understand how they work, one must look at the internal locking mechanism. There are two primary types: integrated and modular. An integrated mechanism engages the shackle directly with the internal components, known as tumblers. For example, in a "Scandinavian" style lock, the key rotates a series of disks. Each disk has a central cutout for the key and notches on its edge. When the correct key is used, these notches line up with cut-outs in the shackle. This alignment allows the shackle to slide out of the body.

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

Because the parts are directly connected to the shackle, these locks usually cannot be disassembled.

Modular mechanisms work differently by using a cylinder to separate the tumblers from the shackle. In these designs, the key turns a plug within the cylinder. This action moves a component called a "locking dog," such as a ball bearing, to retract from notches in the shackle.

bilock
bilock

This separation allows the lock to be more easily serviced or repaired. Modular locks often use pin, wafer, or disc tumblers. Many of these modern designs are also self-locking, meaning they do not require a key to close the shackle.

Padlocks have a very long history spanning thousands of years. Some examples date back to the Roman Era, between 500 BC and 300 AD. Ancient merchants used them while traveling trade routes to Asia. In China, padlocks were used during the late Eastern Han dynasty, from 25 to 220 AD. These early Chinese versions were often made of bronze and used splitting springs or letter combinations. By 850 AD, spring tine mechanisms were being used in Viking settlements like Jorvik in York, England.

As manufacturing improved, new designs emerged to provide better security. In the mid-19th century, Swedish inventor Christopher Polhem created "Polhem" or "Scandinavian" locks. These used a cast iron body and were much more secure than previous "smokehouse" or "screw key" locks. The McWilliams company patented these in 1871, and they remained popular for decades. Later, in 1877, Yale & Towne patented a design using a "cartridge" system. This allowed a stack of levers to be slid into a brass shell, making the lock easy to rekey.

Padlock 4 combination
Padlock 4 combination

Technological shifts in the 20th century changed how padlocks were made. The widespread availability of electricity allowed for metal machining. This led to locks made from solid machined blocks of metal, which resemble modern padlocks. In 1920, Harry Soref founded Master Lock and introduced the laminated padlock. This design used plates punched from sheet metal that were stacked and riveted together.

Steel Cable Padlock
Steel Cable Padlock

This method was very efficient and created a lock that was both strong and inexpensive.

Today, padlock technology continues to evolve into electronic and specialized forms. Active electronic padlocks use rechargeable or replaceable batteries and can be opened via Bluetooth, NFC, or fingerprints. Passive electronic padlocks do not require electricity and use a programmed electronic key.

Passive electronic padlock with key
Passive electronic padlock with key

Other specialized versions include steel cable padlocks, which use flexible shackles to secure large or irregular objects like bicycles. Even the concept of the padlock is used digitally; a lock icon in a web browser indicates that data is protected by encryption.

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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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