Slotted conical spring washer

Abstract

A slotted conical (non-flat) spring washer with an encircling ring provides improved spring washer performance. A split or slotted conical spring washer is encircled by a retaining ring that prevents the ends of the washer adjacent to the slot from expanding as the washer is compressed. The ends of the washer on both sides of the slot move to prevent the washer material from exceeding its yield strength. The ring restricts the radial movement of said outside diameter of the washer strip away from a center axis of the washer bore. The ring can be a counter bore in a member to be clamped, a retaining washer having an outside annular washer to act as the ring, or can be integral with the spring washer such that the slot appears not to pass completely through the washer strip. This slotted conical spring washer greatly increases the elastic spring travel available during repeated clamping cycles and during movement of clamped members due to differences in rates of thermal expansion and thermal gradients. A method for using the slotted spring washer fastening system invention assures electrical conductance and/or fluid vessel integrity under high temperatures and thermal gradients and when different materials are used in the clamped and clamping members.