Lubrication and cooling system for connecting rod and piston

Claim 1

A hydraulic lubricating and cooling system comprising, a crankshaft, at least one main bearing rotatably supporting said crankshaft and defining an oil groove, a source of pressurized oil supplying pressurized oil to said main bearing, at least one crankarm having a crankpin on said crankshaft, a connecting rod having a crankpin end defining a crankpin bearing journaling said crankpin, said crankpin end defining an oil groove forming an arcuate segment adjacent said crankpin on the side of said connecting rod, a piston, a wrist pin connected to said piston, a wrist pin end on said connecting rod defining a wrist pin bearing receiving said wrist pin on said piston and forming an oil groove and an oil orifice for spraying oil on the underside of said piston, means defining a passage in said crankarm of said crankshaft intermittently communicating between said source of pressurized oil through said maiN bearing and said oil groove of said crankpin bearing during a period of asymmetrical timing relation of the crankarm fore and aft of the top dead center position, passage means in said connecting rod for transmitting pressurized oil from said oil groove in crankpin bearing to said oil groove and said oil orifice in said wrist pin bearing, means in at least one of said bearings defining a rotary valve to provide asymmetrical intermittent flow of pressurized oil from said main bearing to said orifice when the inertia forces on the oil in said passages of said connecting rod tend to increase oil flow through said orifice for thereby cooling said piston with a flow rate increasing with engine speed.