Oil supply device

Abstract

An oil supply device includes a plurality of hollow cam shafts, cam shaft journals, and a shaft side path. The hollow cam shafts have through holes that pass in a longitudinal direction from interior to exterior thereof. The cam shaft journals are provided on every position at which the through holes are formed. Each of the cam shaft journals has a path connected with an associated through hole and is coupled with a cylinder head. The shaft side path is formed to supply oil into each hollow cam shaft after the oil sequentially passing from an oil pump through an associated cam shaft journal and an associated through hole.

What is claimed is: 
     
         1 . An oil supply device, comprising:
 a plurality of hollow cam shafts having through holes that pass in a longitudinal direction thereof from an interior to an exterior thereof;   cam shaft journals provided at every position at which the through holes are formed, each of the cam shaft journals having a path fluidly connected with an associated through hole and being coupled with a cylinder head; and   a shaft side path formed to supply oil into each of the hollow cam shafts after the oil sequentially passing from an oil pump through an associated cam shaft journal and an associated through hole.   
     
     
         2 . The oil supply device as set forth in  claim 1 , wherein the shaft side path is connected to any one of the plurality of cam shaft journals to supply oil into an associated hollow cam shaft, and the supplied oil passes through the interior of the hollow cam shaft, such that the oil flows out of the cam shaft through the through holes other than the through hole into which the oil is introduced, thus lubricating between the cam shaft journal and the hollow cam shaft. 
     
     
         3 . The oil supply device as set forth in  claim 1 , further comprising:
 a continuous variable valve timing unit connected at a central portion thereof to a first end of the hollow cam shaft, with a path defined in the continuous variable valve timing unit; and   an oil control valve passing through the central portion of the continuous variable valve timing unit and coupled axially with the first end of the hollow cam shaft, with a path defined in the oil control valve to be connected with the path in the continuous variable valve timing unit.   
     
     
         4 . The oil supply device as set forth in  claim 1 , further comprising:
 an oil-control-valve side path formed to allow the oil to pass from the oil pump through the cylinder head into the first end of the hollow cam shaft.   
     
     
         5 . The oil supply device as set forth in  claim 3 , wherein the hollow cam shaft further comprises on the first end thereof a hole that connects the interior of the hollow cam shaft with the exterior thereof, the oil-control-valve side path is connected to the hole to allow the oil to be introduced into the hollow cam shaft, and the introduced oil is supplied to the oil control valve inserted into the first end of the hollow cam shaft. 
     
     
         6 . The oil supply device as set forth in  claim 3 , wherein the hollow cam shaft comprises on the first end thereof an axial path formed in an axial direction of the hollow cam shaft, a first end of the axial path being connected to the path in the continuous variable valve timing unit, a second end thereof being connected to the oil-control-valve side path. 
     
     
         7 . The oil supply device as set forth in  claim 6 , wherein the oil supplied through the oil-control-valve side path passes through the axial path and flows to the path in the continuous variable valve timing unit, and the oil flowing into the path in the continuous variable valve timing unit flows again into the path defined in the oil control valve, so that the oil is supplied to the oil control valve. 
     
     
         8 . The oil supply device as set forth in  claim 7 , wherein a check valve is provided in the path defined in the continuous variable valve timing unit, so that, if a pressure exceeds a preset level after the path defined in the continuous variable valve timing unit is filled with the oil, the check valve is opened to allow the oil to be introduced into the path defined in the oil control valve. 
     
     
         9 . The oil supply device as set forth in  claim 3 , wherein a hollow is formed in the oil control valve in a longitudinal direction of the oil control valve in such a way as to be open towards the interior of the hollow cam shaft, and a connecting hole is provided in the oil control valve to connect the hollow with the exterior of the oil control valve. 
     
     
         10 . The oil supply device as set forth in  claim 9 , wherein the shaft side path is connected to the cam shaft journal that is nearest to the connecting hole, so that the oil flows sequentially through the cam shaft journal, the through hole and the connecting hole into the hollow, and thereafter is supplied through the hollow into the hollow cam shaft. 
     
     
         11 . The oil supply device as set forth in  claim 10 , wherein a control valve is provided in the hollow at a position opposite to the hollow cam shaft in such a way as to be near to the connecting hole, and, when the oil introduced through the connecting hole exceeds a preset pressure in the hollow, the control valve is opened, so that the oil is supplied to the path defined in the oil control valve.