Resistance adjusting device for non-pull cord window blind

A resistance adjusting device for a non-pull cord window blind, the resistance adjusting device comprising:

• a base having a top opening, a first positioning portion and a fixed shaft having circular cross-section;
• a resistance adjusting seat disposed on the base and having a transmission shaft and a plurality of resistance adjusting rods, the transmission shaft having a transmission hole which is polygon-shaped in cross-sections, the resistance adjusting seat being rotatably sleeved onto the fixed shaft of the base by the transmission hole of the transmission shaft, the plurality of resistance adjusting rods being disposed around the transmission shaft;
• and
• a control pin having a driving shaft, the control pin being sleeved onto the fixed shaft of the base by the driving shaft in a way that the control pin is displaceable vertically and rotatable, the driving shaft having a second positioning portion and a driving portion which is polygon-shaped in cross-sections, the second positioning portion of the driving shaft of the control pin being engaged with the first positioning portion of the base to disable the control pin from rotating when the control pin is located at a positioning position, the second positioning portion of the driving shaft of the control pin being separated from the first positioning portion of the base and the driving portion of the driving shaft of the control pin being embedded in the transmission hole of the transmission shaft of the resistance adjusting seat to enable the control pin to drive the resistance adjusting seat to rotate together with the control pin when the control pin is located at an adjustment position;
• wherein the base is provided on a top surface thereof having a protruded edge formed therein;
• the top opening being formed in an underside of the protruded edge, the protruded edge having a polygonal hole formed therein and defining the first positioning portion, the polygonal hole being disposed in open communication with the top opening;
• the second positioning portion of the control pin is located adjacent to a top end of the driving portion;
• the second positioning portion has polygonal cross-sections;
• the driving shaft of the control pin is provided at a bottom end thereof with a sleeve hole having circular cross-sections;
• the driving shaft of the control pin is rotatably sleeved onto the fixed shaft of the base by the sleeve hole.