Piston-Float Air Churn: Hollow Floats With Pistons Worked by a Fixed Eccentric

Egbert wanted the air "forcibly discharged in small jets at the very point where it is most required, viz, the moving surface of the dasher." D. N. Egbert of Hudson, Ohio, received US 6,727, dated 18 September 1849, for a rotary churn-dasher in a case with a zinc bottom: two sets of arms joined by hollow floats whose sides are pierced with small holes, each fitted with a piston. Connecting rods join the pistons to an eccentric ring running on an eccentric fixed to the end piece, so each float fills with air as it ascends and discharges it as it descends. A strap from a large pulley on the crank shaft to a small one on the dasher's shaft turns it fast. This rung works out the air each float pumps, then prints the floats, pistons, eccentric and arms, builds them over a stainless bottom, and makes butter.