Trailer coupler lock

A trailer coupler lock, wherein a coupler has a spherical chamber, and the coupler lock comprises:

• a lock core frame having an engagement portion and a first lock tongue, wherein the engagement portion is engaged with at least one surface of the coupler, and a sliding groove extending in a first direction is formed in the lock core frame;
• a movable lock head comprising a sliding block and an engagement portion, wherein the sliding block is slidably installed in the sliding groove, a connector is connected with the sliding block and engaged with the spherical chamber of the coupler, and the engagement portion cooperates with the connector to clamp and fix the coupler;
• a limiting piece selectively connected with the lock core frame and the sliding block simultaneously to limit a position of the sliding block in the sliding groove;
• a lock cylinder cover selectively covering an outside of the lock core frame, wherein an avoidance hole is formed in the lock cylinder cover;
• and
• a locking piece arranged at a periphery of the lock cylinder cover, wherein the first lock tongue extends through the avoidance hole and is connected with the locking piece to lock the lock core frame inside the lock cylinder cover in response to the lock cylinder cover being arranged on the outside of the lock core frame.