Transmission assembly with a lock gate structure for an optical disc device for preventing pieces of an optical disc from escaping the optical disc device

An optical disc device for preventing the pieces of exploded disc from flying out of the optical disc device, comprising:

• a main chassis;
• a disc holding down plate, one edge of which is pivotally connected to the main chassis;
• a budging mechanism having a compression shaft and a pushing board, the pushing board mounted on the disc holding down plate, the compression shaft pivotally connected to the disc holding down plate, one end of the compression shaft extending to the working area to mechanically interfere with an optical disc entering the working area, the other end of the compression shaft connected to the pushing board and driving the pushing board to slide;
• a transmission assembly including a longitudinal plate and a driving axle respectively mounted on one side of the main chassis, one side face of the longitudinal plate provided with a sliding sawteeth device that is able to slide in one dimensional direction and match with the sliding of the pushing board, one end of the sliding sawteeth device extending to form a flange to cooperate with the pushing board, the other end of the sliding sawteeth device having, a row of bottom sawteeth, dimension and the extreme sliding positions of the bottom sawteeth fitting for a sliding distance of the longitudinal plate, in a first extreme sliding position the bottom sawteeth meshing with a front gear set up on the driving axle to transmit motive force from the driving axle to the longitudinal plate such that the longitudinal plate is able to move in one dimensional direction;
• and
• a lock gate structure having a driving plate, one edge of the driving plate pivotally connected to a roller, the other edge of the driving plate extending upward to form a lock gate, the driving plate connected pivotally to the main chassis via a pivot for opening or closing a loading slot of the optical disc device;
• wherein the longitudinal plate further has a zigzag shaped first guiding hole defined therein in which the bottom horizontal hole of the first guiding hole is defined as a bottom route, the top horizontal hole of the first guiding hole is defined as a top route, the inclined hole communicating with the bottom and top holes of the first guiding hole is defined as a rising route;
• through the first guiding hole, the longitudinal plate engages with a pole formed on a face of a cam which is pivotally connected to the main chassis;
• the cam also has a through hole defined therein to engage with a guiding column formed on one side of the driving plate of the lock gate structure;
• the pole and the through hole of the cam are located in relative positions such that during the movement of the pole from the bottom route to the top route, the cam drives the lock gate to close the loading slot and during the movement of the pole from the top route to the bottom route, the cam drives the lock gate to open the loading slot.