A lock includes a body defining a first bore having a lock core mounted therein, and a second bore having an engaging element inserted thereinto; and a front barrier shield fixedly mounted in the body in front of the lock core. A communicating hole is formed in the body behind the lock core to communicate the two bores. A locking pin is disposed in the communicating hole to move into or out of a locking hole formed on the engaging element under control of the lock core, so as to lock or release the engaging element to or from the body, respectively. The front barrier shield includes a plurality of axially spaced and staggered barrier sheets to define a zigzag keyway, preventing a thief from peeping through the first bore and destructing the lock core.
The present invention provides a safety interlock system for mechanically securing an industrial process or appliance, including a lock which can be unlocked with a key, wherein the key comprises one or more key code elements which can be positioned in different positions and the selected position of the key code elements corresponds with a specific key code, and wherein the lock comprises one or more lock code elements which can be positioned in different positions and the selected position corresponds with a specific lock code, wherein the lock is locked except when the key code is identical to the lock code when the key is inserted.
A tubular lock is disclosed. The tubular lock includes an outer portion, and an inner portion. A plurality of movable driver pins is disposed between the outer portion and the inner portion. The pins are accessible through a space formed by the outer portion and the inner portion. At least one fixed structure prevents an unauthorized tubular lock picking structure from entering the space.