Quick Release Linkage
This linkage system can be used to slowly pull back on a cable connected to a spring or other elastic device and then suddenly release tension on the cable. As the wheel rotates, the pin is able to capture the first linkage bar (green). Notice that the second linkage bar (red) is raised above the first linkage bar and will never be captured by the pin. Slowly drag the slider to the end and watch the quick release.
Snapshot 1: the linkage in its initial resting position
Snapshot 2: the linkage as the wheel has rotated approximately 180 degrees and has started to rest on the pin
Snapshot 3: the linkage as the wheel has rotated just under 360 degrees and is about to rapidly release away from the pin