Electronic door lock and transmission mechanism thereof

An electronic door lock installed on a door panel, the electronic door lock comprising:

• a first lock body comprises a pedestal member and a covering member;
• a transmission mechanism installed on the first lock body, and comprising:
• a gear box comprising a lower cover and an upper cover, which are combined with each other, wherein the lower cover comprises a first opening and at least one detection hole, and the upper cover comprises a second opening corresponding to the first opening;
• a motor module installed on the lower cover;
• a transmission gear set pivotally coupled with the lower cover and engaged with the motor module;
• a transmission rod, wherein a first end and a second end of the transmission rod are respectively penetrated through the first opening and the second opening;
• a clutch transmission module comprising a clutch gear, a connection element and two stopping elements, wherein the clutch gear has a first surface and a second surface opposite to the first surface, wherein a concave structure is formed in the first surface, two push blocks are disposed within the concave structure, arranged along a same rotation path and opposed to each other, a first pivotal hole runs through a middle region of the concave structure, and two sensing points are formed on the second surface, arranged along a same rotation path and opposed to each other, wherein the transmission rod is penetrated through the first axial hole, so that the clutch gear is pivotally coupled with the transmission rod and engaged with the transmission gear set, wherein the connection element is rotatably embedded within the concave structure, and the connection element and the transmission rod are connected with each other, so that the connection element is linked with the transmission rod, wherein the two stopping elements are installed on two opposite sides of the connection element, and the two stopping elements comprise two stopping parts corresponding to the two push blocks, respectively;
• and
• a motion detection circuit board electrically connected with the motor module and installed on a lateral side of the lower cover away from the upper cover, wherein the motion detection circuit board has a third surface and a fourth surface opposite to the third surface, wherein a returning detection module is installed on the third surface, the returning detection module is installed in the at least one detection hole, the returning detection module comprises a first returning detection unit and a second returning detection unit, and the first returning detection unit and the second returning detection unit are aligned with a rotation path of the two sensing points;
• and
• a latch assembly comprising a latch mandrel, a latch bolt and a torque blade, wherein the latch bolt is received within the latch mandrel, the torque blade is penetrated through the latch mandrel, the torque blade is connected with the first end of the transmission rod, and the latch bolt is selectively protruded out or retracted back through the torque blade,
• wherein while the motor module drives a rotation of the clutch gear through the transmission gear set, the two push blocks are rotated to push the stopping parts of the corresponding stopping elements, and the transmission rod is correspondingly rotated, wherein while the transmission rod is rotated, the torque blade is correspondingly rotated, and the latch bolt is correspondingly protruded out of the latch mandrel, wherein after the latch bolt is protruded to a locking position, the motor module drives a reverse rotation of the clutch gear, and the two push blocks are detached from the corresponding stopping elements, wherein when the motion detection circuit board detects that one of the two sensing points is transferred across at least one of the first returning detection unit and the second returning detection unit, the reverse rotation of the clutch gear is stopped, and a returning process is completed.