| 摘要 |
A ladder drum for adjusting and regulating the angular orientation and closure of horizontal slats of a venetian blind, of the type incorporating ladder cords or tape ladders, having a polygonal profiled structure comprising a series of planar sidewalls defining a substantially hollow interior. The number of sidewalls defining the polygonal structure is greater than four sidewalls, and less than or equal to twelve sidewalls, with each adjacent plane sidewall having an internal angular orientation in the range of 90° to 150°. To enhance the uniform closure of the slats of a horizontal blind, the polygonal ladder drum is more preferably in the form of an uneven hexagon that is either formed from injection molded plastics or a metal die stamping. The opposing top and bottom sidewalls are greater in measurement than the remaining mediate sidewalls, with at least two opposing mediate sidewalls having attachment means to insert and retain ladder cords in a counter balanced relation. The lateral peripheral edges of the profile body have either flared openings or notches to catch and re--spool misaligned ladder cords. Ladder tapes may also be secured to the profile structure through die cut serrated prongs or through the use of a detachable serrated clip. |
