End fittings for flexible hoses

Abstract

A two-piece self-locking end fitting is made from a collar which fits over the end of a plastic hose and an annularly serrated insert which fits within the hose. In one embodiment, after the collar is placed over the end of a thick-walled hose, the insert is placed inside the end of the hose. In another embodiment, an insert is first placed inside a thin-walled hose to give it added body and rigidity. Then, the collar is slipped over the outside end of the hose. In either embodiment, a swaging die is drawn over the collar to reduce its diameter and thereby capture the hose against the annular serrations of the insert. As the diameter reduces, an annular ridge in the collar is automatically canted into an annular valley in the insert to securely lock them together. After the cant takes place, further compression causes the ridge to elongate and lock the insert firmly so that it cannot move relative to the collar, which in turn provides the primary gripping force to hold the hose and fitting together.