A trailer safety device for use in conjunction with a trailer hitch is provided having a bracket assembly from which a free-swinging body assembly is suspended. The bracket assembly and body assembly are positioned in spaced relationship above the trailer hitch to prevent inadvertant or accidential opening of the trailer hitch. The free-swinging body assembly is permitted to swing freely between points of constraint defined by inhibitors such as a bracket shoulder or an inhibitor latch. In this manner, a substantial portion of the body assembly remains positioned directly above the trailer hitch to block its opening and the body assembly absorbs shocks and jolts by swinging to and fro. To open the trailer hitch, the body assembly is manually retracted to one side of its swinging arc thereby enabling the trailer hitch to open.

A safety hitch for connecting a trailer to a towing vehicle, the safety hitch including a plate, that is connected between the trailer tongue and a hitch member mounted on the vehicle, to coact with the ball and socket connection between the trailer tongue and hitch member to prevent dislodgment of the ball of the hitch member from the socket in the trailer tongue. The plate has a keyhole slot formed therethrough such that the plate can be placed on the hitch member and moved to a position to engage small portions of the slot with portions of the hitch member underlying the ball for securing the plate to the hitch member in such position. Upwardly extending, apertured lugs mounted on the base plate engage the sides of the trailer tongue and are pinned thereto via a pin that passes through a hole through the trailer tongue, such hole being positioned to align the socket in the trailer tongue with small portions of the slot. An upwardly extending heel portion of the plate engages the underside of the tongue to prevent the tongue from pivoting off the ball and the engagement of the ball and socket prevents movement of the base plate which would permit the large portion of the slot from becoming aligned with the ball for dislodgment of the base plate from the hitch member.

A security device for a trailer hitch or similar article which engages with an outwardly extending peripherial flange around the trailer hitch or similar article, and which includes an element which extends into a coupling opening in the trailer hitch or similar article, thus precluding removal of the security device from the trailer hitch or similar article. A padlock is utilized to deter unauthorized removal of the security device from the trailer hitch or similar article, and the security device includes means to protect the shackle of the padlock from unauthorized removal.

A releasable locking device for preventing premature coupling of a truck tractor's air braking glad hand to a truck trailer's air braking glad hand is disclosed. The device includes a set of jaws adapted to interlock with each other and the non air-connecting end of a glad hand. A channel integral with the set of jaws houses a barrel lock to effect control of the interlocking of the set of jaws with the non air-connecting end of the glad hand so that, when the set of jaws is interlocked with each other and the non air-connecting end of a glad hand, an operator may not prematurely couple a truck tractor's air brakes to a truck trailer's air brakes.

A trailer decoupling prevention device for preventing the trailer from decoupling from a trailer hitch mounted on a towing vehicle. The trailer decoupling prevention device comprises a bracket, and a connector assembly to connect the bracket to the trailer. A lower plate is movably supported by the bracket. A lower plate stop assembly is provided for selectively permitting movement of the lower plate between a coupled position and an uncoupled position. In the coupled position, at least a portion of the lower plate is positioned to prevent the trailer from being removed from the trailer hitch. In the uncoupled position, the lower plate is positioned to permit removal of the trailer from the trailer hitch. A unique coupling member for selectively coupling a flexible linkage to an attachment member is also disclosed.