Patent ID: 8161927
Filing Date: 2012-04-24
Classification: F01L,F02F

Abstract:
1. A valve system of an overhead-camshaft-type internal combustion engine including a cylinder head having a combustion chamber formed therein, said valve system comprising a camshaft; a cam holder supporting said camshaft, said cam holder being fastened to the cylinder head, and being disposed above said combustion chamber; said cam holder comprising a bottom wall, and a pair of oppositely-facing support walls having lower sides thereof joined to each other by said bottom wall; said pair of oppositely-facing support walls pivotally supporting said cam shaft; a plurality of rocker arms; and a rib joining predetermined oppositely-facing portions of respective upper side portions of said support walls with each other; said rib extending between the upper side portions of said support walls such that a gap is formed between said bottom wall and said rib; wherein said cam holder further comprises a plurality of rocker bearing portions, each of which rockably and pivotally support respective one of said rocker arms in a vicinity of respective side portions of said support walls; and wherein portions of the respective upper side portions of said support walls located above the rocker bearing portions are joined to each other by the rib.