TRANSMISSION CASE

摘要

The converter housing (2) of a transmission case (1) is provided with a plurality of rib portions (7) in an inner surface (2B) and a groove portion (5A) comprising a concave portion (5 a), a thin wall portion (5e) and a raised portion (5c). When an impact load acts on the transmission case (1), at least one rib portions (7A) out of the rib portions (7) concentrate stress to the thin wall portion (5e). Thus, in comparison to the case of providing a slit in the converter housing (2) and disposing a shield material for covering the slit, costs can be reduced by eliminating the need for the shield material.