Schlage introduced the Primus™ high security lock cylinder during the fourth quarter of 1988. Schlage Primus was introduced with key-in-knob/lever, rim and mortise lock cylinders. Primus was Schlage Lock Company's entrance into the high security market place with patent protection. The...
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Schlage introduced the Primus™ high security lock cylinder during the fourth quarter of 1988. Schlage Primus was introduced with key-in-knob/lever, rim and mortise lock cylinders. Primus was Schlage Lock Company's entrance into the high security market place with patent protection.
The Primus cylinder incorporates two independent lock mechanisms having a total of 11 pin tumblers. These are the Schlage six-pin tumbler mechanism and a five finger pin mechanism that operates a sidebar. The pin tumblers and the sidebar create the two shear lines. The six spring-loaded pin tumblers provide security by extending across the shear line requiring the correct bitting configuration in order to align the pin tumblers. There are ten depths of cut (numbers 0-9) for the Schlage pin tumbler locks.
Five spring-loaded finger pins are contained in each Primus lock cylinder. The finger pins are controlled by the key's side millings and function like wafers in a wafer sidebar lock. Each finger pin has an extension that contacts the blade of the key. Each of the five finger pin locations are spaced between each six adjacent pin tumbler chambers.
The original Primus patent incorporated six finger pins (numbers 1-6). Each finger pin has a depth of cut; either shallow or deep. In addition, each finger pin has an angle; either left, center or right. The number one finger pin is shallow and has a left angle of cut. The number two finger pin is deep and has a left angle of cut. The number three finger pin is shallow and has a center angle of cut. The number four finger pin is deep and has a center angle of cut. The number five finger pin is shallow and has a right angle of cut. The number six finger pin is deep and has a right angle of cut.
As the properly cut key is inserted into the keyway of the compatible lock cylinder, the pin tumblers raise and lower according to the bitting configuration. At the same time, the finger pin extensions contact the key blade, raising up and following the side milled cuts. In addition to raising the finger pins to the correct height, the root of each side cut swivels the finger pin extension to one of three positions: left, center or right. When this key is fully inserted, the finger pin gates align with the sidebar notches, creating a pocket for the sidebar to retract into the body of the plug as it rotates. The pin tumblers align at the shear line. The key can be turned, rotating the plug and operating the locking mechanism. The pin tumbler lock mechanism and finger pin lock mechanism are designed to only be operated by a properly cut, patent protected Schlage Primus key.
Patented Primus keys are designed to enter the keyway and operate both Primus and conventional lock cylinders having compatible keyways and bitting configuration for the pin tumblers and finger pins. This ability enables Primus locks and keys to be retrofit into existing Schlage key systems providing high security options as well as the capability to expand the system. To prevent unauthorized duplication of Primus keys, Schlage standard keys will not to enter Primus lock cylinder keyways.
NOTE: All Primus keys are pre-cut with the specific side milling.
The original Schlage Primus patent expired in 2007. New patents have been issued providing patent protection through 2024. This new patent protection has been incorporated into the name Primus XP. To gain the additional patent protection, Schlage Lock Company has made a number of additions, including a seventh depth finger pin and compatible side milling cut in the Primus key.
The 7-pin has a unique angle and milling location that provides an additional level of security. The 7-pin can be installed into existing Primus systems, converting them to XP. This brings the Classic Primus XP sidebar combinations to 7812. Converting an existing Primus system to a Primus XP system requires a new side bar milling having at least one 7-pin finger pin and a new Primus key with new side milling compatible with the change of finger pin(s).
With the correct tools, keying a Primus lock cylinder can be completed in a minimum amount of time for maximum profit.