Patent ID: 7677607
Filing Date: 2010-03-16
Classification: F16L

Abstract:
1. A coupling assembly comprising: a union member including a first receiving portion having internal left-handed threads and a second receiving portion having internal right-handed threads; a first coupling member having external left-handed threads that are threadingly engaged to the internal left-handed threads of the union member; a second coupling member having external right-handed threads that are threadingly engaged to the internal right-handed threads of the union member; and at least two annular seals, one of which is provided between the union member and the first coupling member and the other provided between the union member and the second coupling member; a first retaining element provided between the first coupling member and the union member for limiting axial movement of the first coupling member in a direction away from the second coupling member; and a second retaining element provided between the second coupling member and the union member for limiting axial movement of the second coupling member in a direction away from the first coupling member, wherein at least one of the first and second retaining elements is selected from the group consisting of a split, retaining ring seated in a groove in the union member, a radially inward protruding rib extending from an interior surface of the union member, and radially inward protruding bumps extending from an interior surface of the union member, and wherein, upon rotation of the union member, the length between the first and second coupling members changes.