| 主权项 |
1. A lock device with an automatic locking function, comprising:
a case adapted to be mounted in a door, with the case including a chamber; a latch head slideably received in the chamber, with the latch head slideable in a transverse direction between a latching position outside of the case and an unlatching position in the case; an unlatching mechanism pivotably received in the chamber and including a follower portion operatively connected to the latch head, with the follower portion pivotable between a release position and a pressing position; a base fixed in the chamber, with the base including a track and a groove in communication with the track; a locking block slideably received in the track of the base and including a receiving groove, with the locking block limited by the track and movable in the transverse direction between a front position adjacent to the unlatching mechanism and a rear position distant to the unlatching mechanism; a shaft mounted in the receiving groove of the locking block; a first sliding block slideably mounted on the shaft, with the first sliding block limited by the shaft and movable in the transverse direction between a central position in a central portion of the receiving groove and a non-central position not in the central portion of the receiving groove; a first compression spring mounted around the shaft; a second compression spring mounted around the shaft, with the first sliding block located between the first and second compression springs, with the first and second compression springs biasing the first sliding block to the central position; an electric driving device mounted in the groove of the base, with the electric driving device including a driving shaft having a threaded section at an intermediate portion thereof, with the driving shaft controlled to rotate in a forward direction or a reverse direction opposite to the forward direction; a second sliding block including a screw hole in threading connection with the threaded section of the driving shaft; a follower plate including a first portion coupled to the first sliding block and a second portion coupled to the second sliding block, wherein when the latch head is in latching position, if the unlatching mechanism pivots from the release position towards the pressing position, the latch head moves from the latching position towards the unlatching position, wherein when the unlatching mechanism is in the pressing position, the latch head is in the unlatching position, wherein when the driving shaft rotates in the forward direction, the second sliding block, the follower plate, and the first sliding block move towards the unlatching mechanism, wherein when the driving shaft rotates in the reverse direction, the second sliding block, the follower plate, and the first sliding block move away from the unlatching mechanism, wherein when the unlatching mechanism is in the release position, rotation of the driving shaft in the forward direction causes movement of the locking block from the rear position towards the front position, wherein when the unlatching mechanism is in the pressing position, the locking block is blocked by the unlatching mechanism, rotation of the driving shaft in the forward position causes the first sliding block to move from the central position to the non-central position and to compress the first compression spring, permitting the locking block to be retained in the rear position, wherein when the locking block is in the rear position, the locking block disengages from the unlatching mechanism, permitting the unlatching mechanism to pivot from the release position to the pressing position, wherein when the locking block is in the front position, the locking block engages with the unlatching mechanism, not permitting the unlatching mechanism to pivot from the release position to the pressing position, and wherein when the locking block is in the front position, rotation of the driving shaft in the reverse direction causes movement of the locking block from the front position to the rear position. |
