Abstract: A core bar for a rubber track includes wings on both sides to be embedded in an elastic member of the rubber track, a bridging center for connecting the wings, and driving protrusions provided on both sides of the bridging center and projecting from the inner circumferential surface of the rubber track. The bridging center has at least one projection projecting from the wings in a longitudinal direction of the rubber track. Projections of the core bars embedded in the elastic member overlap with each other to form a continuous passage for a track roller. As an alternative, the core bar includes a driving center protrusion provided at the center of the core bar and adapted to engage a sprocket wheel for driving the rubber track and track roller traveling surfaces extending along the driving center protrusion on both sides thereof.

Abstract: An elastic endless crawler has cords arranged in a crawler body composed of elastic materials such as an endless belt-like rubber material in and along the longitudinal direction of the crawler body. Main cord layers are embedded in the crawler body to restrain elongation of the crawler body in the longitudinal direction. Bias cord layers are also embedded in the crawler body. The bias cords of the bias cord layers are so arranged that they incline reciprocally in mutually-opposite directions in relation to a straight line measured in the transverse direction of the crawler body which intersects the longitudinal direction of the crawler body at a right angle.