US Patent 9145178 Fifth-wheel trailer hitch

A fifth-wheel hitch assembly is provided that converts a gooseneck hitch installed on a vehicle into a fifth-wheel hitch for receiving a kingpin. The hitch assembly generally includes a base assembly, a T-arm assembly for securing the gooseneck ball or gooseneck post of the installed gooseneck hitch, and a hitch head. The T-arm assembly includes a mechanism for pulling up on the gooseneck hitch, thus securing the base assembly against the vehicle bed.