Patent ID: 7378013

Claim:
A coupler for securing a trailer to a vehicle having a tow hitch ball, said coupler comprising: a first coupler section comprised of a generally concave cavity for receiving a tow ball, a cylindrical socket larger than said cavity communicating with said concave cavity and an opening extending to one side of said cylindrical socket; a lock ring having a circular portion with an opening therethrough and an arm portion extending to one side of said circular portion, said circular portion of said lock ring being dimensioned to be matingly received within said cylindrical socket with said arm portion extending through said opening, said lock ring being rotatable in said socket between a first position wherein said opening in said lock ring is aligned with said concave cavity to allow a tow ball to be inserted therein through said opening, and a second position wherein said opening is out of alignment with said concave cavity; and a second coupler section attached to said first housing section to capture said lock ring in said cylindrical socket.