Ductile iron gear and casting process for the production thereof

Abstract

Cast iron gears, such as those used as cam gears on engines and as used for fuel injection gear pumps, which have a hub and a rim that are thick in comparison to the relatively thin web used to interconnect the hub with the rim and a process by which such iron gears can be cast, especially in a vertical orientation. To eliminate porosity problems, single flow channel of substantial thickness is incorporated into the mold cavity which forms a flow rib that runs radially between the hub and rim of the gear being formed. To compensate for both the added weight of the rib that is produced on the web of the resultant gear, as well as to counterbalance the effect caused by the presence of a single rib, at least one opening is formed in the web at each side of the rib.

Dependencies are inferred from the claim text.