Key retainer

A key retainer device (KRD) is a small metal unit that is wall or door mounted, usually designed for the interchangeable core that retains one key (Key A) while the second key (Key B) is used for authorized purposes. When the key in use (Key B) is returned into the key retainer, the key held captive (Key A) is turned and then can be released. Now, the special key, perhaps top master (Key B) is held captive again. The key retainer is a method for providing visual key control.

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Key Retainer for Small Format Interchangeable Cores

A key retainer device (KRD) is a small metal unit that is wall or door mounted, usually designed for the interchangeable core that retains one key (Key A) while the second key (Key B) is used for authorized purposes. When the key in use (Key B) is returned into the key retainer, the key held captive (Key A) is turned and then can be released. Now, the special key, perhaps top master (Key B) is held captive again. The key retainer is a method for providing visual key control.

Applications

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These include janitorial or custodial staff, irregular or temporary users, guests and other authorized users that require access to a certain key but to whom that key is not issued directly. The KRD acts as a "mechanical sign-out sheet", physically controlling access to the key and providing accountability for its eventual return.

Operation

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One key (High Level/Special) is retained in a core (at 1/4 turn) until another "release" key is inserted in the other core and rotated 90° (1/4 turn). Then the "retained" key can be removed for use while the "release" key is held (trapped) for visual accountability purposes. This cycle is repeated in reverse when the normally "retained" key is returned and the "release" key is removed "retrieved" by the authorized user.

Padlocks

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The term "key retainer" can also refer to a padlock that does not allow the key to be removed when the shackle is in the open position. This prevents accidentally leaving the padlock unlocked, and it also prevents accidentally locking the key inside a locker, shed, etc.

References

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v t e Locks, locksmithing, lock picking, and security alarms
Fundamental concepts	Access control Authentication Key control Key duplication Key relevance Master keying Password Physical security Rekeying
Lock hardware	Bitting Interchangeable core Key blank Key code Key retainer Lockrod Lockset Bored cylindrical lock Mortise lock Rim lock Single-point locking Three-point locking
Keys	Berlin key Car key Keychain Skeleton key Smart key
Mechanical locks	Warded lock Pin tumbler lock Disc tumbler lock Lever tumbler lock Magnetic keyed lock Padlock Combination lock Rotary combination lock Time-delay combination locks Time lock Tubular pin tumbler lock Wafer tumbler lock
Electronic locks	Electromagnetic lock Electronic lock Electric strike Keycard lock
Other lock types	Arrow lock Bicycle lock Bramah lock Chubb detector lock Child safety lock Kensington Security Slot Latch Luggage lock Power door locks Protector lock Real-estate lock box Steering-wheel lock The Club
Lock picking	Lock bumping Locksport Slim Jim Snap gun
Door hardware	Dead bolt Door chain Door closer Door frame Door furniture Door handle Door security Doorstop Hinge Night latch
Emergency access/exit	Crash bar Electromagnetic door holder Emergency exit Emergency light Exit control lock Exit sign Knox Box
Security alarms	Alarm device Alarm monitoring center Car alarm Card reader Closed-circuit television Door loop Dual loop Fingerprint scanner Glass break detector Heat detector Key switch Keypad Miniature snap-action switch Motion detector Occupancy sensor Passive infrared sensor (PIR) Perimeter intrusion detection Photoelectric sensor Piezo switch Pressure switch Proximity card Reed switch Tripwire Ultrasonic transducer Vandal-resistant switch Water detector Window security
Miscellaneous	Glossary of locksmithing terms John M. Mossman Lock Museum Key to the City Lock Museum Lock Museum of America Musée de la Serrure Puzzle lock
Category:Locksmithing Keys Locks Book

Key retainer

Applications

Operation

Padlocks

See also

References