Coupling lock for an engine and a boat hull

A coupling lock for an engine and a boat hull comprising a base dock and a upper dock, wherein:

• the base dock is fastened to a transom of the boat hull and has two fastening rods extended from the bottom thereof, each of the fastening rods having a first gear rack on an inner side;
• and
• the upper dock includes a frame and a lock body housed in the frame to allow the fastening rods to run through and couple therewith,
• wherein the lock body held in the upper dock includes a lock plug, a lock case, a lock core, two latch members, two sliding plates and two springs;
• wherein:
• the lock plug has a housing chamber in a center thereof to hold the lock core, two latch troughs on two ends of a front side corresponding to each other, a sliding trough on a lower side communicating with the two latch troughs and the housing chamber located thereabove;
• the lock case is a hollow member located between the frame and a retaining plate to hold the lock plug, and has apertures on two sides to allow the fastening rods to run through;
• the lock core is housed in the housing chamber of the lock plug and has a keyway on one end and a lock bolt on another end which is turnable about a fixed point when the keyway rotates to perform locking and unlocking operation;
• the two latch members are located in the latch troughs and have respectively a second gear rack on one side mating the fastening rod and two stubs extended respectively from the upper side and the lower side;
• the two sliding plates are located in the sliding trough in an inverse manner, and have one end coupled with the lower side of the latch member and another end forming a hook to latch one side of the lock bolt such that the turning of the lock bolt controls the movement of the latch members to engage or disengage the second gear rack with the first gear rack of the fastening rods;
• and
• the two springs are located in the latch trough and have one end pressing one side of the latch members.