HELICAL
When a solid describes a combined translational and rotational movement around its central axis (the thread of a screw is helical), it is called helical. A so-called “cylindrical” balance spring is in fact a helical spring.
When a solid describes a combined translational and rotational movement around its central axis (the thread of a screw is helical), it is called helical. A so-called “cylindrical” balance spring is in fact a helical spring.