Shear pin coupling

Claim 1

A shear pin flexible coupling for connecting two shafts, comprising: two coupling halves each connectable to one of said shafts and each including a radially extending annular flange spaced from and confronting the flange of the other half, said flanges having spaced bores which can be aligned with the like bores of the opposite flange; an outer bushing fitted into each bore, each outer bushing having a central opening the surfaces of which tapers inwardly toward the gap between the flanges; an inner bushing having a single split and being received in each outer bushing, said inner bushing having a central opening and an outer surface which is tapered to complement the taper of the outer bushing; elongated shear pins extending across the gap and having two circular cylindrical ends of like diameter disposed within the tapered inner bushings, and a central annular groove disposed in said gap; and means for forcing the inner bushings in the direction of the gap to rigidly grasp the shear pins with an interference fit, said forcing means each comprising a circular loading plate having a rim which bears against the outer end of the split bushing and having a central bore, and a headed bolt having its shank extending through the central bore and threaded received into one end of the shear pin.