Padlocks

Padlocks are portable locks with a shackle that may be passed through an opening (such as a chain link, or hasp staple) to prevent , theft, vandalism or harm.

There are padlocks dating to the Roman Era, 500 BC – 300 AD. They were known in early times by merchants traveling the ancient trade routes to Asia, including China.

Padlocks have been used in Europe since the middle La Tène period, subsequently spreading to the Roman world and the Przeworsk and Chernyakhov cultures. Roman padlocks had a long bent rod attached to the case, and a shorter piece which could be inserted into the case. Przeworsk and Chernyakhov padlocks had a sleeve attached to the case, and a long bent rod which could be inserted into the case and the sleeve.

Padlocks have been used in China since the late Eastern Han Dynasty (25–220 AD). According to Hong-Sen Yan, director of the National Science and Technology Museum, early Chinese padlocks were mainly "key-operated locks with splitting springs, and partially keyless letter combination locks". Padlocks were made from bronze, brass, silver, and other materials. The use of bronze was more prevalent for the early Chinese padlocks.

Padlocks with spring tine mechanisms have been found in York, England, at the Jorvik Viking settlement, dated 850 AD. During this period between 850 AD and the early 1000 AD was when the name 'padlock' was coined. It was contrived during this period to initially hold livestock within its quarters of the paddock, whereby the word pad was derived and applied to form the current word.

Smokehouse locks, designed in England, were formed from wrought iron sheet and employed simple lever and ward mechanisms. These locks afforded little protection against forced and surreptitious entry. Contemporary with the smokehouse padlocks and originating in the Slavic areas of Europe, "screw key" padlocks opened with a helical key that was threaded into the keyhole. The key pulled the locking bolt open against a strong spring. Padlocks that offered more key variance were the demise of the screw lock. Improved manufacturing methods allowed the manufacture of better padlocks that put an end to the Smokehouse around 1910.

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Wikipedia