Automotive crankcase vapor ventilation system

• Main Author: DALLMAN; ALFRED C
• Format: Patent
• Language: English
• Published: 06.04.1999
• Edition: 6
• Subjects: BLASTING; COMBUSTION ENGINES; HEATING; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS; LIGHTING; MECHANICAL ENGINEERING; SUPPLYING COMBUSTION ENGINES IN GENERAL, WITH COMBUSTIBLEMIXTURES OR CONSTITUENTS THEREOF; WEAPONS

A crankcase ventilation system withdraws vapors from the crankcase of an internal combustion engine by using intake manifold vacuum to transfer crankcase vapors from a position in the engine crankcase, away from any lubricant pool, into the air/fuel intake manifold system, thereby moving the crankcase vapors along with a controlled amount of bleed (ambient) air to the intake manifold of the engine. The engine crankcase is kept under negative pressure by careful sizing of the parts, and the intake tube for bleed air is the only air admission to the crankcase so as to maintain this negative pressure condition within the engine crankcase. The bleed air intake tube is located adjacent the outlet tube for combining crankcase vapors and bleed air, without particulate or contaminates from the crankcase, and directed to the engine fuel/air intake manifold through a thermal cooling chamber. Any existing ventilation air inlet port is blocked (in retrofit to existing systems) and is not provided in OEM systems according to the invention. Recirculation of blow-by gases, and bleed air is aided by the fact that the crankcase vapors are in transit from a hot crankcase region to a much cooler vapor region.