Curtain body locating mechanism of a curtain with no cord

A curtain body locating mechanism for use in a curtain with no cord, comprising:

• a fixed base with an upper guide groove and a lower guide groove disposed at two ends thereof respectively, wherein the upper guide groove and the lower guide groove on each end correspond with each other;
• two first driving wheels disposed on the fixed base rotatably and engaged with each other;
• a coil spring configured to connect the two first driving wheels and optionally winded onto one of the two first driving wheels;
• two second driving wheels disposed on the fixed base rotatably and engaged with the two first driving wheels respectively;
• two driving ropes, one end of each of the two driving ropes being connected to a respective one of the second driving wheels;
• and
• a resistance unit having two movable shafts, at least one tension spring, two stoppers and two resistance wheels, wherein upper and the bottom ends of each of the movable shafts are inserted movably into the respective upper guide groove and the lower guide groove at each end of the fixed base respectively, the tension spring is connected to the two moveable shafts, each of the two stoppers is disposed on the fixed base and located between one of the second driving wheels and one of the moveable shafts, respectively, each of the resistance wheels is rotatably nested on a respective one of the movable shafts and is winded around by one of the driving ropes so that each of the resistance wheels can be separated from the stopper by the pulling force of the driving rope and clamped to the stopper through the elastic restoring force of the tension spring.