Patent attributes
A trailer lock and particularly a trailer lock for locking a trailer ball cap includes a lock housing, a lock, a latch bolt, a holding seat and a detent member. The lock housing has an opening to hold the lock, a U-shaped trough to hold the latch bolt, a through trough to hold the holding seat and allow the detent member to slide on the holding seat. The lock has a housing chamber on one side to couple with the trailer ball cap. The latch bolt can control movement of the detent member by turning of the lock so that the detent member is wedged in a latch trough on one end of the latch bolt, and a latch end of the latch bolt is extended and anchored in the housing chamber of the lock housing and locked on the trailer ball cap. When the trailer is separated from a vehicle, the trailer ball cannot be coupled thereby to provide theft-proof function.