The oldest known lock was found by archeologists in the Khorsabad palace ruins near Nineveh. The lock was estimated to be 4,000 years old. It was a forerunner to a pin tumbler type of lock, and a common Egyptian lock for the time. This lock worked using a large wooden bolt to secure a door, which had a slot with several holes in its upper surface. The holes were filled with wooden pegs that prevented the bolt from being opened.
The first serious attempt to improve the security of the lock was made in 1778 in England. Robert Barron patented a double-acting tumbler lock.
Joseph Bramah patented the safety lock in 1784. Bramah's lock was considered unpickable. The inventor went on to create a Hydrostatic Machine, a beer-pump, the four-cock, a quill-sharpener, a working planer, and more. Joseph Bramah
In I857, James Sargent invented the world's first successful key-changeable combination lock. His lock became popular with safe manufacturers and the United States Treasury Department. In 1873, Sargent patented a time lock mechanism that became the prototype of those being used in contemporary bank vaults.
Mr. Samuel Segal (former New York City policeman) invented the first jimmy proof locks in 1916. Segal holds over twenty-five patents.
Soref founded the Master Lock Company in 1921 and patented an improved padlock. In April 1924, he received a patent (U.S #1,490,987) for his new lock casing. Soref made a padlock that was both strong and chea using a case constructed out of layers of metal, like the doors of a bank vault. He designed his padlock using laminated steel.
Linus Yale Sr.
Linus Yale invented a pin-tumbler lock in 1848. His son improved upon his lock using a smaller, flat key with serrated edges that is the basis of modern pin-tumbler locks.
Linus Yale Jr. (1821-1868)
American, Linus Yale Jr. was an mechanical engineer and lock manufacturer who patented a cylinder pin-tumbler lock in 1861. Yale invented the modern combination lock in 1862.