Roller blind and control device thereof

A roller blind, comprising:

• a linkage assembly, including an outer tube connected with a curtain fabric;
• and
• a control device, disposed at one end of the outer tube and engaged with the outer tube, the control device comprising:
• a reeling mechanism, having an engaging portion;
• a solenoid valve, disposed in the reeling mechanism;
• a push mechanism, movably disposed on the reeling mechanism, the push mechanism being connected with the solenoid valve;
• a front cap, engaged with the engaging portion of the reeling mechanism, the front cap being connected with the push mechanism;
• a damper, disposed in the reeling mechanism;
• an outer rod disposed in the outer tube and a limiting mechanism disposed on the outer rod and engaged with the outer tube;
• and
• a tail seat disposed at another end of the outer tube, an inner rod being disposed in the tail seat, the inner rod being connected with the outer rod;
• when an operation portion of the inner rod is operated to rotate the inner rod, the inner rod drives the outer rod to rotate relative to the outer tube, so that a slider is rotationally moved on an inner tube to adjust a distance between the slider and the limiting seat,
• wherein the limiting mechanism includes the inner tube sleeved on one end of the outer rod, a slider and a limiting seat that are rotationally movable in the inner tube, the slider has a first threaded portion, the inner tube has a second threaded portion, the first threaded portion of the slider is meshed with the second threaded portion of the inner tube, the outer tube has a limiting rib located in a limiting portion of the slider, when the outer tube is rotated to lower the curtain fabric, the outer tube drives the slider to rotate and move on the inner tube along the limiting rib in cooperation with the second threaded portion;
• when the slider is pushed against the limiting seat, the slider drives the outer tube to stop rotating,
• wherein after the solenoid valve is energized, the solenoid valve drives the push mechanism to push against the front cap so as to separate the front cap from the engaging portion, and the reeling mechanism is not subject to a resistance of the damper to drive the outer tube to rotate so as to lower the curtain fabric, wherein the inner rod includes a first coupling member, a second coupling member is disposed on the tail seat, a return elastic member is sleeved on the inner rod;
• when the first coupling member of the inner rod is disengaged from the second coupling member of the tail seat by operating the operation portion, the return elastic member stores a return elastic potential energy, and the inner rod drives the outer rod to rotate relative to the outer tube;
• when the operation portion is released, the return elastic member releases the return elastic potential energy to return the inner rod, so that the first coupling member of the inner rod is engaged with the second coupling member.