Patent ID: 7886805

Claim:
A spring tensioning unit for a roll-up closure, the closure having: a pair of end plates; an axle rotatably mounted between and on the end plates; a drum for carrying a closure, the drum rotatably mounted on the axle; and a tensioning coil spring mounted on the axle and connected between the axle and the drum; the unit having: a ratchet wheel fixedly mounted on the axle adjacent one end plate, the wheel having spaced-apart teeth on its periphery; a stop member slidably mounted on the one end plate with a stop tab cooperating with the teeth on the wheel to stop movement of the wheel in a direction reducing tension on the spring; a lever mounted between the wheel and the end plate, the lever having a lever tab for cooperating with the wheel, the lever movable on the axle both radially and rotationaly to position the lever tab against a tooth and to then rotate the tooth, and the axle, in a direction to increase tension on the spring.