Engine Crankcase Breathing Passage With Flow Diode

摘要

An internal combustion engine is disclosed which includes an improved crankcase drain back system. A set of drain flow diodes are disposed in each of the drain lines to direct fluid flow in a direction from the head portion to the crankcase. Likewise, a set of breather flow diodes are disposed in the breather lines to direct fluid flow in a second direction from the cylinder portion to the head portion. The flow diodes include a series of stacked flow diode elements which allow flow in one direction, while resisting flow in the opposite direction.

主权项

1. An oil drain back system for an internal combustion engine comprising:
a drain line extending between an upper region and a lower region of an engine, the drain line having a preferred direction of drain flow from the upper region to the lower region; a breather line extending between the lower region and the upper region, the breather line having a preferred direction of breather flow from the lower region to the upper region; and a preferential flow passageway associated with at least one of the drain line and the breather line, the preferential flow passageway having a flow diode disposed therein and oriented to direct fluid flow in the preferred direction of the at least one of the drain line and the breather line; wherein a pressure differential across the flow diode for flow in preferred direction is less than the pressure differential across the flow diode for flow in a direction opposite the preferred direction.