Valve operating mechanism of an internal combustion engine

Abstract

To operate a poppet valve in an internal combustion engine, a valve operating mechanism comprises a valve spring retainer which has a taper bore, a pair of cotters which is inserted in the bore to support the poppet valve, and a valve spring between the valve spring retainer and a cylinder head. There is provided means for preventing the cotters from falling out the bore.

What is claimed is:  
     
         1 . A valve operating mechanism for a poppet valve of an internal combustion engine, said mechanism comprising: 
 a light alloy valve spring retainer which has a taper bore;    a pair of cotters which is engaged in the taper bore of the valve spring retainer, each of the cotters having a bead in an inner circumferential surface, said beads being engaged in an annular groove of an end of the poppet valve;    a valve spring provided between said valve spring retainer and a cylinder head, and    means for preventing the cotters from falling out of the bore of the valve spring retainer.    
     
     
         2 . A valve operating mechanism as claimed in  claim 1  wherein said means for preventing the cotters from falling out of the bore comprises an outer circumferential rough surface of the cotters to be engaged in an inner circumferential surface of the bore of the valve spring retainer.  
     
     
         3 . A valve operating mechanism as claimed in  claim 1  wherein said means for preventing the cotters from failing out of the bore comprises a smaller diameter portion at a lower end of the bore of the valve spring retainer.  
     
     
         4 . A valve operating mechanism as claimed in  claim 3  wherein the smaller diameter portion comprises an annular projection.  
     
     
         5 . A valve operating mechanism as claimed in  claim 3  wherein the smaller diameter portion comprises an inner circumferential surface tapered at an angle larger than the tapered surface of the bore.