Patent attributes
A fifth wheel includes a top plate having a throat that is adapted to receive a kingpin of a trailer. The fifth wheel is equipped with a locking mechanism including a jaw slidably connected to the top plate and slidable between a closed position where the jaw blocks passage of a kingpin out of the throat of the fifth wheel and an open position where a kingpin may pass into and out of the throat of the fifth wheel. The jaw has an edge adapted to engage a kingpin positioned in the throat of the fifth wheel when the jaw is in the closed position. A release arm is pivotally attached to the top plate and the jaw. A trigger member is pivotally attached to the release arm and has a locking head. A main spring urges the jaw towards the closed position. A locking protrusion is attached to the top plate and is engaged by the locking head of the trigger member when the jaw is in the open position so as to prevent the jaw from moving into the closed position. A release member is pivotally attached to the distal end portion of the release arm.