Supporting structure for engine timing chain

Abstract

A supporting structure for an engine timing chain comprising a chain guide for artificially limiting vertical movement of the timing chain near a camshaft sprocket, thereby reducing any abnormal engagement between the timing chain and camshaft sprocket while the camshaft sprocket is in motion, decreasing noise, and increasing the life of the components.

What is claimed is:  
     
         1 . An engine timing chain assembly, comprising: 
 a timing chain installed around a crankshaft sprocket and a camshaft sprocket to allow a camshaft and a crankshaft to interact with each other for periodically opening and closing intake and exhaust valves; and    a chain guide for guiding movement of said timing chain in close proximity to said camshaft sprocket and for restricting vertical movement of said timing chain.    
     
     
         2 . The assembly as defined in  claim 1 , wherein said chain guide is installed between an intake camshaft sprocket and an exhaust camshaft sprocket.  
     
     
         3 . The assembly as defined in  claim 1 , wherein said chain guide comprises: 
 a body part having a guide groove at its rear portion for allowing said timing chain to be inserted therein; and    a mounting boss part integrally formed at a lower portion of said body part for fixing said chain guide.    
     
     
         4 . The assembly as defined in  claim 1 , wherein said chain guide is secured at a cam cap mounted on a journal part of the cylinder head.  
     
     
         5 . The assembly as defined in  claim 4 , wherein said cam cap is integrally formed for simultaneously fixing an intake camshaft and an exhaust camshaft at said journal part of the cylinder head.  
     
     
         6 . The assembly as defined in  claim 5 , wherein said cam cap further comprises: 
 receptive grooves formed at both ends thereof for supporting the intake and exhaust camshafts; and    a mounting boss part integrally protruded from a front center of said cam cap for securing said chain guide.    
     
     
         7 . The assembly as defined in  claim 6 , wherein a cut-out portion is formed at a rear portion of said mounting boss part for reducing the weight of the components.  
     
     
         8 . The assembly as defined in  claim 1 , wherein said chain guide is integrally formed to said cam cap mounted at said journal part of the cylinder head.