Ventilation door device for refrigerator

A ventilation door device for a refrigerator, including:

• a frame having an end plate provided with an opening portion, and having a blocking plate assembly rotatably mounted to the end plate, the blocking plate assembly is able to rotate between a closed position where the opening portion is completely closed and an open position where the opening portion is completely open;
• a housing engaging the frame and forming a driving chamber between the housing and the frame;
• and
• a driving module at least partially being held in the driving chamber and configured to drive the blocking plate assembly to rotate;
• wherein the frame has a housing engagement portion located at the side edge of the end plate and extending substantially perpendicular to the end plate, and the housing is connected to the housing engagement portion of the frame;
• wherein the blocking plate assembly includes a blocking plate to be installed on the end plate and an elastic component disposed on the blocking plate, when the blocking plate assembly is in the closed position, the elastic component abuts the frame and elastically deforms to seal the opening portion;
• and
• wherein the end plate of the frame has a sealing portion arranged around the opening portion and protruding from the end plate, and when the blocking plate assembly is in the closed position, the elastic component abuts the sealing portion of the frame,
• wherein the driving module comprises:
• a stepper motor;
• a teeth missing gear connected to the stepper motor;
• a sector gear meshing with the teeth missing gear;
• and
• an output shaft connected to the sector gear and connected to the blocking plate;
• wherein the stepper motor can drive the blocking plate to rotate via the teeth missing gear, the sector gear and the output shaft,
• wherein the outer periphery of the teeth missing gear has an arc section next to its teeth section;
• when the blocking plate is in the closed position, the outer surface of the arc section of the teeth missing gear abuts the sector gear, thereby preventing the sector gear from rotating in the direction of opening the blocking plate, and
• wherein the outer periphery of the sector gear has a concave locking arc next to its teeth section, and the concave locking arc is recessed toward the center of the sector gear;
• when the blocking plate is in the closed position, a part of the arc section enters the interior of the concave locking arc, preventing the concave locking arc from rotating relative to the arc section, thereby the teeth missing gear prevents the sector gear from rotating in the direction of opening the blocking plate.