US Patent 7806425 Trailer hitch

A trailer hitch having a retaining latch bolt to reduce shaking includes a locking head, a bolt seat, a retaining element, a latch bolt and an elastic element. The retaining element has a first directing rib to be rapidly positioned in a first bolt aperture of a first coupling member. The bolt seat has a positioning rib anchored in a second bolt aperture of a second coupling member to facilitate coupling of the first coupling member and the second coupling member. Hence the latch bolt can be coupled easily and adjustment of coupling tolerance can be performed as desired. Locking can be done to thwart pilferage of the trailer. And the latch bolt can be held firmly without sliding or shaking.