Ladder tape device for a venetian blind

A ladder tape device for a venetian blind, comprising:

• a U-shaped fixing base fixed in a head rail of the venetian blind;
• a ladder tape retainer with opposite ends placed on corresponding two side-panels of the fixing base;
• a plurality of ladder tapes with a top end of each ladder tape passing through the fixing base and being wound on the ladder tape retainer;
• and
• a limiting cover buckled on the top end of the fixing base, wherein an inner wall of the limiting cover and an outer wall of the top end of the ladder tape retainer are separated by a predetermined distance to form a ladder tape limiting space;
• wherein an opening is integrally defined in a middle of the limiting cover with two narrow openings at opposite ends of the opening and a wide opening between and communicating with the narrow openings, and the wide opening and the narrow openings are arranged in a line parallel to an axial direction of the ladder tape retainer;
• wherein a width of the wide opening in a direction perpendicular to the axial direction of the ladder tape retainer is greater than widths of the narrow openings in the direction perpendicular to the axial direction of the ladder tape retainer;
• the plurality of ladder tapes is wound on a portion of the ladder tape retainer below the wide opening.