Flap for circular air duct - with coil spring fitting to cut-outs in duct interior

摘要

The circular air duct is fitted with a special flap (3) which has an outside contour to fit the circular wall of the duct. The flap is fitted with a coil spring whose two coil sections (8) are each provided with a free end (11) which is clipped into small cut-outs (13) in the wall of the duct. The spring closes the flap and the system requires no further attachments to the duct to secure the flap. The flap is operated by a rod or Bowden cable attached to a cutout of the flap.