Patent ID: 7438064

Claim:
A mixture-lubricated internal combustion engine comprising: a cylinder defining a combustion chamber; a piston disposed in said cylinder so as to move back and forth therein and to delimit said combustion chamber; a crankcase connected to said cylinder; a crankshaft rotatably journalled in said crankcase and driven by said piston; said cylinder having an intake inlet communicating with said combustion chamber; an inlet channel for supplying fuel and combustion air to said intake inlet; said cylinder having an exhaust outlet through which exhaust gases pass from said combustion chamber; a valve system for controlling the opening and closing of said intake inlet and said exhaust outlet; a flow connection between said crankcase and said inlet channel for facilitating a lubrication of said crankcase as a consequence of pressure pulsations in said inlet channel and said crankcase; a control valve disposed in said flow connection between said crankcase and said inlet channel; said control valve being movable between first and second positions which are independent of an angular position of said crankshaft; and, said control valve substantially closing said flow connection in said first position when said engine is in idle and said control valve having a maximum open cross section in said second position when said engine is at full-load operation.