NZ592048A - Pin cylinder lock assembly with biased tumbler pins - Google Patents

Abstract

592048 A pin tumbler cylinder lock assembly comprising a cylinder housing 501, a plug 502 rotatably mounted in the cylinder housing 501, a keyway extending along the longitudinal axis of the plug 502 and open at a front end of the plug 502 to allow insertion of a key, a plurality of tumbler pin passageways extending inwardly from the circumference of the plug 502 to the keyway, and a plurality of driver pin passageways extending outwardly from the interior of the cylinder housing 501, the tumbler pin passageways being aligned with the driver pin passageways in one rotational position of the plug 502, a plurality of tumbler pins 4B, 4D slidably mounted in respective tumbler pin passageways, a plurality of driver pins slidably mounted in respective driver pin passageways and a plurality of resilient biasing means for resiliently biasing respective driver pins inwardly. The tumbler pins 4B, 4D include a telescopic tumbler pin assembly including an outer pin and an inner pin slidably mounted in the outer pin. The inner pin or outer pin are arranged to be resiliently biased inwardly by the associated driver pin and the outer pin is arranged to be biased relative to the inner pin by resilient means 505A acting between the inner and outer pins. The plug 502 is prevented from rotating relative to the cylinder housing 501 by the telescopic tumbler pin assembly except when the radially inner end of the outer pin of the telescopic pin assembly projects inwardly into the keyway further by a predetermined amount than the radially inner end of the inner pin of the telescopic pin assembly.