Ratchet Lock

I returned to the study and targeted the roller shade suspended across the window frame. Clamping the center pull-ring with my right claw, I applied steady downward displacement. The internal roller rotated smoothly. At seventy centimeters of vertical travel, three audible clicks registered from the right-hand ratchet cap: centrifugal pawls clearing the gear teeth. I decelerated travel speed by twelve percent. The gravity pawl dropped into the nearest locking notch with an acoustic snap. Torsion spring held static under load. Darkness sealed across the glass pane. Counterbalance equilibrium verified.