Energy absorber device with composite plastic casing having high

Abstract

A fluid energy absorber device, such as a fluid spring or shock absorber, or a combination of both, having a composite casing of an outer cylinder of molded plastic around an inner high strength plastic cylinder having high strength fibers therein, the high strength fibers extending both longitudinally and circumferentially, with the circumferential fibers preferably being a high strength plastic which will permit the casing to expand radially. The inner cylinder may be a separate plastic cylinder containing the high strength fibers and to which the outer cylinder is bonded, or the inner cylinder may be formed by a matrix of plastic which is a continuation of the outer cylinder. The high strength cylinder may be located between inner and outer plastic cylinders which are fused to each other to encapsulate the high strength cylinder. A method of fabricating a fluid energy absorber device having a high strength composite casing including the steps of providing a tubular high strength inner member having high strength fibers therein, mounting the inner member on a mandrel, and forming an outer plastic cylinder about the inner member so that the resulting casing includes an outer plastic cylinder and an high strength inner cylinder having high strength fibers therein. The method may include mounting the high strength member on a plastic cylinder which was previously mounted on the mandrel, and thereafter forming the outer plastic cylinder so as to cause its ends to fuse to the ends of the inner plastic cylinder to encapsulate the high strength member.