| 摘要 |
<p>A novel push button operated combination lock has a series of plungers on either side of a central channel in which the bolt operates. The plungers are notched differently on their respective sides and the combination may be changed by releasing the plungers and reversing them in their channels. The bolt is not releasable unless the correct plungers and only the correct plungers are depressed and there is no means of knowing from the push buttons which plungers or how many plungers must be depressed. The plungers may be reset by pressing the bolt for a new attempt at the right combination or to lock the mechanism. Although the mechanism is readily reset to change the combination when the cover is removed, the cover may only be removed when the bolt is out of the mechanism, securing it against tampering. A variety of forms are shown in which the mechanism is used on a security chain, a padlock, a window lock, and a dead bolt mechanism.</p> |
