Patent ID: 6199646
Filing Date: 2001-03-13
Classification: B62D

Abstract:
A working vehicle comprising:a body frame;front wheels;propelling drive shafts disposed in a rear portion of said body frame; andsemicrawler units receiving drive from said propelling drive shafts, respectively, each of said semicrawler units including:a drive rolling element attached to one of said propelling drive shafts;an endless crawler track driven by said drive rolling element and contacting a ground;driven rolling elements engaged by said endless crawler track; anda track frame supporting said driven rolling elements, said driven rolling elements distributed in a forward end and a rearward end of said track frame, said track frame pivotally connected to a pivot shaft extending from one of said track frame and said body frame, wherein said track frame and said driven rolling elements remain at a fixed distance from said pivot shaft during operation of said working vehicle.