The entire lock is self-contained within the one-half inch plug diameter.
It includes two parallel rows of six pin tumblers with each row acting
independently with its own side bar. The equivalent of two side bar locks in a
one-half inch cylinder! Each side of the lock is operated separately by each half
of the dual-bladed key. Both the lock mechanism and the key forming process
are patented worldwide. Only the factory and authorized BiLock Service
Centers can duplicate the keys.
Every BiLock cylinder consists of a plug, 2 sidebars, 8, 10 or 12 pin tumblers
and springs, and a cap that holds
the pins and springs in the plug. There are only15 different pin tumblers, all of the same size and shape. Four
are common pins which accept only one depth of cut in the key each (e.g., a #1, 2, 3 or 4 depth cut). The
common pins have a second dummy hole to frustrate picking. The other eleven pin tumblers are master pins
that will accept from 2 to 4 depths of cut on the key.
When the key is inserted in to the lock. the pin tumblers are
to form a shear line on each side of the lock. This allows the spring-loaded
sidebars to locate the deep holes on the pin tumblers, and to retract so that
the lock can be turned to the open position. When the key is returned to the
locked position and withdrawn, the spring-loaded side bars are forced into
the slots in the lock body ­p; which places the cylinder in the locked
position. In the locked position, all pin tumblers rest on the bottom of the
keyway, making it impossible to read the combination or impression the key.
Essential to the BiLock system is the unique dual-bladed, "U" shaped key.
Each side of the key is cut
differently and engages its own set of pin tumblers and side bars. The key blank is originally uncut in
a 90° form. There are no key blanks of this type available anywhere else in the world. The uncut
blank can only be cut and formed with proprietary equipment at the factory or at an authorized
BiLock Service Center. The blank is cut to code on both sides and then formed into the "U" shape
­p; a patented process. The colored key head (18 different colors) is then inserted and crimped
securely into place.
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