Various types of tread pattern are designed depending on the usage of tire. However, there are few papers described about the relationship between the shape of tread rubber block and dynamic characteristics.
The authors measured the dynamic characteristics of rubber block when it is slid to the various directions.
As a result, it is understood that there is the special relation between the shape of block and the sliding direction.
Generally, when a material body was slid, the direction of frictional force should correspond to a sliding direction.
On the other hand, different results were provided in the case of rubber block. When the shape of block was symmetric toward the sliding direction, the direction of force corresponded to a sliding direction. However, in case of asymmetry, the direction of force did not agree with it, and it is found that the certain tendency was seen in a difference of the direction by the shape. Every shape of block except a circle-shaped, this tendency always occurs.
On this account, the deflection of direction of cornering force of a tire is expected by arrangement of blocks on the tread. Therefore, in design of tread pattern, it will be necessary to arrange the shape and the direction of blocks so that the tendency that each block has is canceled.