Intake valve for lessening accumulation of high boiling fraction from fuel

Abstract

An intake valve for a combustion engine includes a valve guide having a bore and a lower end surface surrounding the bore, and a valve stem having an upper valve stem portion moving up and down within the bore of the valve guide and a valve at the lower end of the stem. A valve guide shield is carried by the valve stem below the upper valve stem portion that moves up and down within the bore to shield the upper valve stem portion from high boiling fraction material from the fuel to lessen the accumulation of high boiling fraction between the valve stem and the valve guide.

1 . An intake valve for a combustion engine comprising:
 a valve guide having a bore and a lower end surface surrounding the bore;   a valve stem having an upper valve stem portion moving up and down within the bore of the valve guide and a valve at the lower end of the stem;   and a valve guide shield carried by the valve stem below the upper valve stem portion moving up and down within the bore to shield the upper valve stem portion from high boiling fraction material from the fuel to lessen the accumulation of high boiling fraction between the valve stem and the valve guide.   
     
     
         2 . The intake valve of  claim 1  further comprising the valve stem shield being of integral one-piece construction with the valve stem. 
     
     
         3 . The intake valve of  claim 1  further comprising the valve stem shield being a hollow washer that seats on the valve stem and is attached thereto. 
     
     
         4 . The intake valve of  claim 3  further comprising the valve stem shield being attached to the valve stem by welding. 
     
     
         5 . The intake valve of  claim 1  further comprising said valve guide shield closely approaching the lower end face of the valve guide when the valve stem is moved up. 
     
     
         6 . The intake valve of  claim 1  further comprising said valve guide shield having a diameter that is sufficient to shield the upper portion of the valve stem from blow back of combustion product toward the valve when the valve is in the open position. 
     
     
         7 . The intake valve of  claim 1  further comprising said valve guide shield being located on the valve stem so as to closely approach the lower end face of the valve guide when the valve stem is moved up, and being of a diameter sufficient to shield the upper portion of the valve stem from blowback of the combustion products when the valve stem is lowered to open the valve. 
     
     
         8 . An intake valve for a combustion engine comprising:
 a valve guide having a bore and a lower end surface surrounding the bore;   a valve stem having an upper valve stem portion moving up and down within the bore of the valve guide and a valve at the lower end of the stem;   and a disc-shaped valve guide shield carried by the valve stem below the upper valve stem portion moving up and down within the bore, said valve guide shield being located on the valve stem so as to approach the lower end face of the valve guide when the valve stem is moved up to open the valve, and being of a diameter sufficient to shield the upper portion of the valve stem from blowback of the combustion products when the valve stem is lowered to open the valve.   
     
     
         9 . The intake valve of  claim 8  further comprising the valve stem shield being of integral one-piece construction with the valve stem. 
     
     
         10 . The intake valve of  claim 8  further comprising the valve stem shield being a hollow washer that seats on the valve stem and is attached thereto. 
     
     
         11 . The intake valve of  claim 8  further comprising the valve stem shield being a disc shaped washer that fits onto the stem, and a weld that attaches the washer to the valve stem. 
     
     
         12 . An intake valve for a combustion engine comprising:
 a valve guide having a bore and a lower end surface surrounding the bore;   a valve stem having an upper valve stem portion moving up and down within the bore of the valve guide and a valve at the lower end of the stem;   and a valve guide shield of disc shape formed in one-piece with the valve stem below the upper valve stem portion to shield the upper valve stem portion from high boiling fraction material from the fuel to lessen the accumulation of high boiling fraction between the valve stem and the valve guide.   
     
     
         13 . The intake valve of  claim 12  further comprising said valve guide shield closely approaching the lower end face of the valve guide when the valve stem is moved up. 
     
     
         14 . The intake valve of  claim 12  further comprising said valve guide shield having a diameter that is sufficient to shield the upper portion of the valve stem from blow back of combustion product toward the valve when the valve is in the open position. 
     
     
         15 . The intake valve of  claim 12  further comprising said valve guide shield being located on the valve stem so as to closely approach the lower end face of the valve guide when the valve stem is moved up, and being of a diameter sufficient to shield the supper portion of the valve stem from blowback of the combustion products when the valve stem is lowered to open the valve.