초록 ▼

A novel apparatus and method are provided to reduce the interlaminar shear loading in the retention area of composite springs used in a vibration isolator for use with a helicopter main rotor. The composite springs, which are made of a graphite laminate, are weakest when subject to inter-laminate sh

A novel apparatus and method are provided to reduce the interlaminar shear loading in the retention area of composite springs used in a vibration isolator for use with a helicopter main rotor. The composite springs, which are made of a graphite laminate, are weakest when subject to inter-laminate shear. The shear forces are highest during bending and twisting about the longitudinal axis of the laminate composite. The invention consists of several techniques to minimize the inter-laminate shear. The first is the use of nylon mounting pads which are attached to the ends of the graphite laminate spring arm at the locations where mounting to the inner and outer hubs is to take place. In particular, it has been found that the nylon spacer must be recessed back from the perimeter edges of the graphite spring arm the same distance which is approximately equal to the width of the graphite spring arm. Next the location of the bolt holes in the spring arm must be critically located so as to avoid that portion of the spring arm which has the highest shear loading.

대표청구항 ▼

[ What is claimed is:] [1.]1. A vibration isolator assembly adapted for rotation about an axis, said assembly comprising:an inner hub adaptable for mounting on said axis;an outer hub having a predetermined inertial mass; anda plurality of spiral shaped spring arms, each said arm having a body with a

[ What is claimed is:] [1.]1. A vibration isolator assembly adapted for rotation about an axis, said assembly comprising:an inner hub adaptable for mounting on said axis;an outer hub having a predetermined inertial mass; anda plurality of spiral shaped spring arms, each said arm having a body with a first retention portion connected to said inner hub and a second retention portion connected to said outer hub;at least one pad disposed on at least one of said first retention portion or said second retention portion; and whereineach said spring arm includes said at least one pad disposed between said first retention portion and said inner hub and a second pad disposed between said second retention portion and said outer hub.