| 摘要 |
<p>A door latch mechanism has a pivoted latch disposed between a retaining solenoid and a four-bar toggle linkage. The toggle linkage connects the operating stem of the solenoid to the latch, has an under-the-center arrangement in a direction away from the solenoid in the latched position of the mechanism, and provides a substantial mechanical advantage to amplify the holding force of the solenoid. When the solenoid is de-energized and pressure is applied to open the door, the latch pivots and the toggle linkage collapses to release the keeper bar. The keeper bar is trapped but has a limited movement in both horizontal and vertical directions in a plane substantially parallel to the pivot axis of the latch. the overall arrangement is relatively simple, compact, inexpensive, easy to install, and reliable in its operation.</p> |
