Wis. Stat. § 167.18: Threshing machine joints to be covered.

Any person owning or running any threshing machine in this state so constructed that any joint, knuckle or jack thereof is dangerously exposed, who shall neglect to cover or secure the same in some suitable manner so as to prevent injury to persons passing over or near the same, shall be punished by fine not exceeding $50 nor less than $2.