History of the Lock: America
With a rich history and industrial boom not seen before in the last few hundred years, America, a young country in comparison to European countries, has had its fair share of history, invention and of course, locks.
Anyone familiar with the history of America is sure to know the influence of the English in its early days. The British kept quite a "tight ship" of its skilled craftsmen and their works thus keeping their patents and laborers from prospering elsewhere. American locks had a poor showing for many years and struggled in sales and craftsmanship until and American physician by the name of Abraham O. Stansbury was granted an English patent in 1805 for his pin tumbler lock which was based on the principles of Bramah's and the Egyptian locks.
This design was granted the first lock patent two years later by the United States Patent and Trademark Office. While this particular lock was never manufactured for sale it featured a double acting pin tumbler and segmented pins that automatically recoiled when any of the tumblers were pushed too far.
Improved upon locks like the one invented by Soloman Andrews had adjustable tumblers and keys and allowed for rekeying at any time. Since the feature of rekeying relied on more skilled but hard to find locksmiths they were used more for businesses such as banks and not for the home. Partnered with another lock inventor by the name of Newell, Soloman Andrews received patents on the removable tumbler lock that could be disassembled and scrambled in the 1850's. This lock was built with a double set of internal levers and had interchangeable bits which matched the varied arrangements of the tumblers making it painstakingly difficult at that time. Alfred C. Hobbs, a legend in the locksmith world for picking Jeremiah Chubb's famous lock, came along in the 1850's as well and patented what he termed "Protector" locks. While they certainly had their protective qualities, they were shown to be flawed and defeated early on.
American locks have shown much by way of improvement over the years from 1805 to 1865 with Linus Yale's "Quadruplex" bank lock in 1844 that featured designs based on Stansbury and Bramah, as well as the ancient Egyptian design. His son, Linus Yale Jr. improved on his fathers design so much that he is credited as the inventor of the modern pin tumbler lock. Yale Jr. also invented the Cylinder Lock in 1865, considered as the most important lock design and development creating a new standard in the industry. While providing higher levels of security this lock not only could not be rekeyed but could be used on varieties of doors and sizes, be mass produced and showed that keys no longer needed to pass through the width of a door to make its way to the bolt mechanism or tumblers, allowing for smaller, thinner keys.
There has not been a lot in the basic design of locks that has occurred since the mid to late 1800's in the United States, however some notable locks are the interlocking deadbolt (aka jimmy-proof rim lock) in 1916, an interchangeable core developed in 1920, the Blake Brothers door latch that was designed with two connecting doorknobs, setting the standard for lock design today. The Walter Schlage cylindrical lock in 1928 which also incorporated a locking mechanism between two knobs, Chicago Lock Companies "Chicago Ace Lock", a tubular key lock and the high security mechanical locks invented by Medeco in 1967.As time has progressed, so have locks and we see that a history of security has provided so much for the present day locks and their inspiration.