Method of and apparatus for producing valve rotors

摘要

The invention provides a method of and apparatus for imparting a required metering form to the longitudinal outer edges of axially extending grooves of cylindrical rotor members of rotary valves by moving an impressing tool or tools having the required metering form thereon against a said edge or edges of a rotor member or members generally in the direction of a chord extending between a point on said edge and a similar point on an adjacent edge of the nearest adjacent groove so as to displace the material of the edge being worked away from the groove.