A trapezoidal non-pneumatic tire ("TNPT") is integrally molded from a stiff, resilient elastomeric material with particular specifications, to form a unitary structure comprising outer and inner cylindrical coaxial members ("hoops"), the outer being wider than the inner. The outer hoop is supported and...http://www.google.com.au/patents/US4921029?utm_source=gb-gplus-sharePatent US4921029 - Trapezoidal non-pneumatic tire with supporting and cushioning members
