| 摘要 |
<p>A pin tumbler lock of a first embodiment includes a shell containing top pin s; and a plug, rotatable within the shell, containing standard bottom pins, and a shorter bottom pin, set back from the face of the plug. A tubular key has bitings corresponding to the standard bottom pins, and a projection corresponding to the short bottom pin. When the key i s inserted, the bitings and the projection press all the bottom pins to the shear line. In a second embodiment, a lock includes a shell containing top pins and a depression; an d a plug, rotatable within the shell, containing bottom pins. The depression is configured and dimensioned to receive one of the bottom pins. The depression may be opposit e one of the bottom pins, and there may be one more bottom pin than top pins. When the ke y is inserted, the bottom pins are moved to the shear line.</p> |
