Spring-Return Rocking Churn: Springs Under Each End Lift the Low One Back

In a rocking churn the cream runs from end to end, and its weight makes each return stroke hard work. Daniel F. Hitt of Galena, Illinois, received US 2,800, dated 7 October 1842, for a churn whose body rocks on gudgeons at its middle, with a spring under each end connected to the body by a strap, cord or chain. As the cream "runs from end to end of the containing vessel, it acquires a momentum"; "by means of the reaction of the springs, the momentum thus acquired is rendered available in obtaining the return motion." A perforated diaphragm across the middle lets the cream through on its way. This rung estimates the spring force, then prints the diaphragm and gudgeon bosses, bows two spring-steel strips under a rocking box, and makes butter.