Patent ID: 8740492

Claim:
A coupling comprising: a hook, the hook comprising opposed upper and lower portions, with a pull axis extending generally between the upper and lower portions, the upper portion comprising a slot for receiving a lifting strap, and the lower portion comprising a circular cutout and an insertion opening extending from a periphery of the cutout to an outer edge of the hook, wherein the insertion opening extends at an angle relative to the pull axis; an elongate housing, the housing comprising opposing upper and lower ends, with a housing axis extending generally between the upper and lower ends, the lower end configured to connect to a lifting bracket, and the upper end of the housing comprising a lateral notch, the housing further comprising a circular opening extending through the upper end thereof extending substantially perpendicular to and intersecting the notch, wherein a width of the notch is greater than a thickness of the hook, such that the lower portion of the hook is insertable into the notch so that the circular cutout of the hook is aligned with the circular opening of the housing; and an elongate shaft, wherein the shaft is resiliently mounted to the housing via a biasing member so as to be slidable within the circular opening of the housing, the shaft comprising a cylindrical portion and a flattened portion opposite the cylindrical portion, the cylindrical portion defining a diameter substantially corresponding to a diameter of the circular opening, and the flattened portion defined by opposing flats extending substantially parallel to the housing axis; wherein the coupling is movable between: a locked position, wherein the lower portion of the hook is inserted into the notch, the cylindrical portion of the shaft is biased by the biasing member into the notch and through the circular cutout of the hook, and the hook is rotated so that the insertion opening is non-parallel to the housing axis, thereby locking the hook to the housing about the shaft, and whereby moving the hook along the pull axis moves the housing in substantially the same direction; and an unlocked position, wherein the lower portion of the hook is inserted into the notch, the flattened portion of the shaft is pressed against the biasing member into the notch and through the circular cutout of the hook, and the hook is rotated so that the insertion opening is aligned parallel to the opposed flats of the flattened portion of the shaft, whereby moving the hook away from the housing along the housing axis releases the hook from the housing.