Abstract: A composite mixture of spherical objects and lubricant useful for its cushioning properties is disclosed and claimed. The composite mixture may be composed of microspheres typically less than 2000 microns in diameter with inert atmospheres sealed within their interiors and any of a variety of lubricants facilitating sliding and rolling movement between microspheres. Typically the composite mixture includes lubricant in a quantity sufficient to substantially coat the exterior surface of essentially all of the spherical objects, but in a quantity less than would cause dispersion of the spherical objects in the lubricant sufficient to physically separate the spherical objects from each other and substantially reduce the sliding and rolling contact of the spherical objects with each other. A low specific gravity, low thermal mass, low coefficient of heat transfer, insulative and flotation qualities are provided by the invention.

Abstract: A lightweight wheel assembly intended primarily for use on wheelchairs including an injection-moldable fiber-reinforced plastic push rim, injection-moldable fiber-reinforced plastic wedge-bottom spokes, and a lockable static in-hub brake. Important advantages of the invention include very light weight compared to prior art wheel assemblies while achieving the high component strength desired, shock absorption qualities beneficial to wheelchair users not provided by other wheel assemblies, a convenient and easy-to-operate positive-engaging static brake, and components which may be made from the inexpensive injection molding process.

Abstract: A spoke for wheels of bicycles, wheelchairs, and the like includes an injection molded discontinuous fiber reinforced plastic shaft formed to have an airfoil shape cross-section, to be oriented in the wheel so as to provide the least wind drag. The shaft is formed with an axially extending threaded first hollow at a first end and an axially extending second hollow at a second end. The spoke further includes an elongate hub element formed with a bend at one end and threads at the other end for screwing into the first hollow of the shaft, and an elongate bar for insertion and securing at one end into the second hollow of the shaft. Threads are formed at the other end of the bar for connecting to the rim of the wheel.