Cylinder head assembly with oil reflector for lubrication of a rocker arm

Abstract

A cylinder head assembly includes a cylinder head defining a port for selectively communicating air to a combustion chamber of an engine or for selectively discharging exhaust gases from the combustion chamber. The cylinder head also defines a valve seat between the port and the combustion chamber. A combustion valve is mounted in the cylinder head and is selectively seated and unseated with the valve seat. A camshaft with a lobe is mounted in the cylinder head. A rocker arm is engaged with the combustion valve and has a follower for following the lobe. An oil spray source provides a spray of oil while an oil reflector is configured to receive the spray of oil and direct the spray of oil to the follower to provide lubrication between the interface of the follower and the lobe.

1 . A cylinder head assembly for an internal combustion engine having a piston reciprocatable within a cylinder, a crankshaft rotated by said piston, and a combustion chamber defined between said cylinder head assembly and said piston, said cylinder head assembly allowing air into said combustion chamber and allowing exhaust gases out of said combustion chamber, said cylinder head assembly comprising:
 a cylinder head defining a port for selectively communicating said air to said combustion chamber or for selectively discharging said exhaust gases from said combustion chamber and also defining a valve seat between said port and said combustion chamber;   a combustion valve mounted in said cylinder head and selectively seated and unseated with said valve seat;   a camshaft mounted in said cylinder head, rotatable about a camshaft axis, and having a high lift lobe and a low lift lobe;   a rocker arm engaged with said combustion valve and having a high lift follower and a low lift follower, said rocker arm being switchable between 1) a high lift mode for receiving high lift valve opening and closing motion from said high lift lobe of said camshaft and 2) a low lift mode for receiving low lift opening and closing motion from said low lift lobe of said camshaft, whereby rotation of said camshaft about said camshaft axis causes said rocker arm to pivot, thereby seating and unseating said combustion valve with said valve seat in a cyclic pattern;   an oil spray source providing a spray of oil; and   an oil reflector configured to receive said spray of oil and direct said spray of oil to one of said high lift follower and said low lift follower to provide lubrication between said one of said high lift follower and said low lift follower and one of said high lift lobe and said low lift lobe.   
     
     
         2 . The cylinder head assembly as in  claim 1  further comprising a camshaft bearing defined by a first semicircular recess in said cylinder head and a second semicircular recess defined in a bearing cap, said bearing cap being fastened to said cylinder head and capturing said camshaft between said first semicircular recess and said second semicircular recess to define a journal bearing interface between said camshaft bearing and said camshaft; wherein said camshaft bearing is said oil spray source. 
     
     
         3 . The cylinder head assembly as in  claim 2  further comprising an oil gallery defined within said cylinder head and in fluid communication with said camshaft bearing to supply oil to lubricate said journal bearing interface, whereby said oil supplied to said camshaft bearing is discharged from said journal bearing interface to generate said spray of oil. 
     
     
         4 . The cylinder head assembly as in  claim 2  wherein said oil reflector comprises:
 a mounting portion for securing said oil reflector to said cylinder head assembly; and 
 a directing portion extending from said mounting portion to receive and direct said spray of oil. 
 
     
     
         5 . The cylinder head assembly as in  claim 4  wherein said mounting portion and said bearing cap are secured to said cylinder head with a fastener such that said bearing cap is captured between said mounting portion and said cylinder head. 
     
     
         6 . The cylinder head assembly as in  claim 5  wherein said mounting portion is planar. 
     
     
         7 . The cylinder head assembly as in  claim 4  wherein said directing portion is has a concave side and a convex side such that said concave side receives and directs said spray of oil. 
     
     
         8 . The cylinder head assembly as in  claim 7  wherein said directing portion is dome-shaped. 
     
     
         9 . A cylinder head assembly for an internal combustion engine having a piston reciprocatable within a cylinder, a crankshaft rotated by said piston, and a combustion chamber defined between said cylinder head assembly and said piston, said cylinder head assembly allowing air into said combustion chamber and allowing exhaust gases out of said combustion chamber, said cylinder head assembly comprising:
 a cylinder head defining a port for selectively communicating said air to said combustion chamber or for selectively discharging said exhaust gases from said combustion chamber and also defining a valve seat between said port and said combustion chamber;   a combustion valve mounted in said cylinder head and selectively seated and unseated with said valve seat;   a camshaft mounted in said cylinder head, rotatable about a camshaft axis, and having a lobe;   a rocker arm engaged with said combustion valve and having a follower for following said lobe of said camshaft, whereby rotation of said camshaft about said camshaft axis causes said rocker arm to pivot thereby seating and unseating said combustion valve with said valve seat in a cyclic pattern;   an oil spray source providing a spray of oil; and   an oil reflector configured to receive said spray of oil and direct said spray of oil to said follower to provide lubrication between said follower and said lobe.   
     
     
         10 . The cylinder head assembly as in  claim 9  further comprising a camshaft bearing defined by a first semicircular recess in said cylinder head and a second semicircular recess defined in a bearing cap, said bearing cap being fastened to said cylinder head and capturing said camshaft between said first semicircular recess and said second semicircular recess to define a journal bearing interface between said camshaft bearing and said camshaft; wherein said camshaft bearing is said oil spray source. 
     
     
         11 . The cylinder head assembly as in  claim 10  further comprising an oil gallery defined within said cylinder head and in fluid communication with said camshaft bearing to supply oil to lubricate said journal bearing interface, whereby said oil supplied to said camshaft bearing is discharged from said journal bearing interface to generate said spray of oil. 
     
     
         12 . The cylinder head assembly as in  claim 10  wherein said oil reflector comprises:
 a mounting portion for securing said oil reflector to said cylinder head assembly; and 
 a directing portion extending from said mounting portion to receive and direct said spray of oil. 
 
     
     
         13 . The cylinder head assembly as in  claim 12  wherein said mounting portion and said bearing cap are secured to said cylinder head with a fastener such that said bearing cap is captured between said mounting portion and said cylinder head. 
     
     
         14 . The cylinder head assembly as in  claim 13  wherein said mounting portion is planar. 
     
     
         15 . The cylinder head assembly as in  claim 12  wherein said directing portion is has a concave side and a convex side such that said concave side receives and directs said spray of oil. 
     
     
         16 . The cylinder head assembly as in  claim 15  wherein said directing portion is dome-shaped. 
     
     
         17 . A cylinder head assembly having a cylinder head, a camshaft with a lobe mounted within a camshaft bearing, and a rocker arm with a follower for following said lobe, said camshaft and said camshaft bearing defining a journal bearing interface lubricated with pressurized oil from an oil gallery such that said oil is discharged from said journal bearing interface to form a spray of oil, said cylinder head comprising:
 an oil reflector configured to receive said spray of oil and direct said spray of oil to said follower to provide lubrication between said follower and said lobe.