Rotational energy absorbing coupling

Abstract

A rotational energy absorbing coupling for shaft-to-shaft and shaft-to-crank applications such as a tiller arm for a steerable strut for hydrofoil ship using a plurality of shear pins spaced in a circular pattern. A first, inner disc is affixed to one shaft and has a circular repeating sequential pattern of a round hole, and a plurality of slots of increasing length all chamfered at the edges. At least a second disc or outer disc are connected to the other coaxial shaft or crank with extended arms and, when more than one is used are sandwiched over the first disc. These discs have a circular pattern of round holes chamfered at the edges and in register with the holes and the center of the slots of the inner disc. A plurality of axially aligned shear pins pass through all the aligned holes thus providing progressive bending of the shear pins due to the chamfered holes, then the shearing of the pins when an overload occurs. The arrangement allows the energy to be absorbed by the plastic deformation (in either direction) of the shear pins in the chamfered holes.

Dependencies are inferred from the claim text.