| 摘要 |
<p>A cylinder lock has a plug (2) provided with coaxial pin passages (6, 8) arranged to accommodate lock pins (7, 9). At least one pin (9) has a necked portion (9a) and a head (9b), and at least one of the pin passages (6) exhibits a widened portion (6a). The pin head (9b) has a smaller diameter than the major part of the pin, and the widened portion (6a) of the recess has a smaller radius in a direction transversely of the axis of plug (2) than half the pin diameter. One or more disc-like pin members (11) may be provided between upper and lower pins (9, 7), these disc-like pin members being prevented from entering the widened portion of the recess when activating the lock with the correct key. The arrangement is such, however, that the head (9b) is readily hooked-up when an attempt to pick the lock is made.</p> |
