History of Locks
Primitive Locks - Spring Barb Locks
By Brian Morland
» THE LOCKING DEVICES OF antiquity through to the years just before the Industrial Revolution are a fascinating subject in relation to the development of the lock . It ’ s one of our areas of study ; locks made of wood , bronze and iron when applied to the ward and tumbler and the incredible variety of ways they were applied with increasing complexity and skill in many ways is the foundation for locksmiths and social understanding for historians . Therefore common to both is how a feature archives its aim together with the skills and need for the invention in the first place .
One such feature is the Spring Barb lock , it ’ s very ancient and in some specialised cases even overlapped into the mid-20th century with such things as police handcuffs ; it ’ s not known by who or where it was invented . They appeared in the back and forth movements in that ancient trade route arc stretching from the Far East through the Middle East and on into Europe no doubt inspiring smiths as they encountered them . Often described as medieval , but were known to have been used by the ancient Chinese , the Romans and the smiths of Europe , finally falling out of general use around the mid-Georgian period ; pockets of use continue to this day particularly in places like India and Iran where this traditional style padlock is very often associated with an affirmation to a deity or prophet . They can be grouped into three distinct categories each style compressing the
A typical sliding key padlock from the Far East , the key is inserted into a key hole in the end of the lock and pushed along the slot thus compressing the barbs and releasing the sliding shackle part at the other end .
Artefact No . 5094 .
‘ pockets of use continue to this day particularly in places like India and Iran where this traditional style of padlock is very often associated with an affirmation to a deity or prophet ’
spring with the key in different ways ; sliding key , turning key and screw key .
The sliding key is formed in such a way as to compress one or more springs , which are set along the inside of the body but fixed at one end only . These springs or barbs have a flared tension ; the key as it is pushed into the lock compressing the barbs into the shape of an aperture pierced into the hasp part thus allowing it to slide thereby releasing it from the body .
In this example of a turning key padlock and is typical of European styles . The key is inserted from the side and as it is turned the barbs are compressed releasing the shackle . The key does not make a full revolution but is simply turned back and removed , to lock the shackle is reinserted when the attached spring barbs will compress as it pushed home and snap locked .
Artefact No . 1630 .
In the Screw key style a helical spring holds a pin into the shackle ; at the top end of this pin bolt is a threaded portion corresponding to a mated portion on the key . A few turns of the key draws the pin bolt against the spring and out of the shackle .
Artefact No . 1633 .
Turning key locks compress the spring barbs as the key is rotated . The keys are fabricated by first beating out a rectangular sheet of iron of the appropriate size at the anvil ; it ’ s then rolled to form a tube . The bow and bit are again formed at the anvil and finally assembled .
Cross section schematic of a typical sliding key lock from the Far East .
Another version of the sliding key lock but this time with the addition of external wards . In this style the key is inserted vertically from the bottom and drawn horizontally to open passing external wards .
28
MAR / APR 2022
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