Acf Industries, Incorporated

Ronald D VanDyke

James C Hammonds

Patricia S Stoller

In accordance with the present invention a lock block link 34 has a first end 36 connected to a trailer hitch bumper block 22 and a second end 40 which engages a lock block 46 which holds the hitch jaws 16 in closed position. The lock block link 34 is supported by an operating shaft link 54 extending from a manual operating shaft 50 extending to the side of the hitch. When the bumper block 22 is engaged by a tractor, the bumper block rotates about pins 30 connecting the bumper block to the hitch head 10. This rotation moves the lock block link 34 and in turn the lock block 46 rearwardly, which allows the jaws 16 to rotate to open position to allow exit of the trailer king pin. A lost motion connection 31 is provided in the connection between the first end of the lock block link and the bumper block to allow the lock block link 34 to move relative to the bumper block when the lock block 46 is moved rearwardly manually by the operating shaft. This connection may comprise at least one elongated slot 32 in the bumper block into which fits the first end of the lock block link.

Combination manual and automatic unlocking mechanism for trailer hitch

A tractor operated hitch is provided including a vertical strut and a diagonal strut, each connected to the hitch head and which provide the sole support for the hitch head. A bumper block assembly is pivotably mounted about the hitch head which depends from and extends outwardly from the hitch head in a direction away from the diagonal strut a distance sufficient to locate a bumper within the industry standard distance above the deck. On the opposite side of its pivot point the bumper block assembly is connected to a diagonal strut linkage which, upon application of sufficient force by the tractor to the bumper, will pivot the bumper block assembly about its pivot point and disconnect the diagonal strut linkage from an upright, engaged position to a retracted position on the deck. The vertical strut is provided with a bumper block assembly slot located between transversely spaced vertical legs or in a transverse wall portion whereby in retracted position the hitch and the bumper block assembly do not extend more than six (6) inches above the deck. This allows other tractors and trailers to pass over the retracted hitch and complies with the industry standard concerning tractor operated hitches in the retracted position.

Collapsible trailer hitch bumper block assembly

A hitch head or fifth wheel is provided including a pair of pivotable jaws which hold in place a kingpin of a highway trailer. A horizontally movable lock block, biased by a stiff spring to closed position, engages the jaws and holds them in closed position, maintaining the kingpin in place. The lock block is movable to an open position by a finger extending through an opening in the lock block. The finger is rigidly attached to a horizontally extending operating shaft which is rotatable by a handle to move the finger to an overcenter position holding the lock block in open position. The finger includes a transversely extending protrusion which is engaged by the jaws as the kingpin exits to pivot the finger from the overcenter position and allow the lock block to move to a position engaging the rear portion of the jaws, holding the jaws open until another kingpin enters the jaws and pivots the jaws to closed position.

Growing community of inventors

Florissant, MO, United States of America

Ronald D VanDyke