Single-Actuator Synchronized Double-Leaf Hatch Linkage Calculator

How the synchronized double-leaf hatch works

The actuator moves the lower arm of a central bell crank. One connecting rod reaches the left lid; the other reaches the right lid. Both lids lift from their outside hinges and meet at the middle when shut. The animation keeps each connecting rod at a fixed length while it moves.

This is a dimensionally consistent illustration based on the supplied reference images, not a reconstruction of measured hardware. Enter the real pivot and bracket dimensions before fabrication or ordering an actuator.

Adjusting actuator positions

Set the clear opening width, fully open angle and total weight of both moving lids. Enter measured hinge, seal or spring resistance if known. Use the four mount sliders to move the actuator’s fixed frame pin and moving crank pin in X and Y. The drawing, required stroke and force recalculate through the full sweep, so you can compare actuator families and lengths. The example starts with a 6-inch Super Duty actuator; the Actuator matches tab checks other catalogue options against the calculated force, stroke and pin lengths.

Before building the hatch

Check rod and lid interference through the complete motion. Design rigid mounts for every hinge and pivot, positive stops and a means of safely supporting or locking the open lids. Verify the actuator’s push and pull ratings, duty cycle and limit settings. The example does not include wind, snow, impact or unmeasured friction loads.