摘要 |
A curved, tetrahelix bicycle crank arm com-posed of a helical array of tetrahedra is disclosed. This design will transmit the propelling force away from the top dead center point providing more efficient use of the propelling energy. With this tetrahelical design a hollow core is possible that will reduce weight and permit lubrication if needed without reducing strength. This design is also applicable to the connecting rod of internal or external combustion engine. |