Internal combustion engine with improved cylinder wall lubrication system

摘要

An internal combustion engine is provided with fluid passages between adjacent cylinders. The fluid passages extend through walls that separate adjacent cylinders and are located axially within the cylinders at positions which advantageously define the periods when the fluid passages are blocked and unblocked by pistons moving within lower cylinders. Pressure differentials between adjacent crankcases cause pooled liquid lubricant to be pumped downward through the fluid passages and placed in liquid communication with the walls of the lower cylinder. This pumping action removes pooled lubricant from the transfer passages of one cylinder and causes the liquid lubricant to flow along the walls of a lower cylinder.