Patent ID: 6152098
Filing Date: 2000-11-28
Classification: F01L,F02B

Abstract:
An internal combustion engine for a portable handheld work apparatus, said internal combustion engine comprising:an engine housing including a cylinder and a crankcase;a piston disposed in said cylinder so as to be movable upwardly and downwardly;said cylinder defining a combustion chamber delimited by said piston;said engine housing including an overflow channel leading from said crankcase into said combustion chamber and an outlet channel branching off of said combustion chamber;a crankshaft rotatably journalled in said crankcase;a connecting rod interconnecting said piston and said crankshaft so as to permit said piston to rotate said crankshaft;an inlet valve for controlling said overflow channel and an outlet valve for controlling said outlet channel;a valve control for controlling the opening and closing of said inlet and outlet valves;a cam drive housing separate from said crankcase and defining an oil sump containing lubricating oil;a cam drive for driving said valve control and said cam drive being a gear-wheel drive mounted in said cam drive housing; and,said gear-wheel drive including a plurality of gear wheels and at least one of said gear wheels being mounted in said cam drive housing so as to at least partially dip into said oil sump thereby moving oil to lubricate said cam drive as well as the movable parts of said engine including said valve control.