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简单汽化曲轴箱扫气二冲程发动机产生的排放主要是由扫气过程中在排气口损失的新鲜充量造成的。这些损失导致油耗增加及对环境的副作用。多年来，由于排放和油耗方面的问题，使二冲程发动机的用量有所减少。但由于其具有结构简单、功率密度高及生产成本低等特点，使它能继续用于助力车、摩托车、小舷外机及小型动力等。尽管如此，由于排放法规日趋严格并对许多种发动机做出了新规定，使简单二冲程发动机受到了四冲程发动机的挑战。本文介绍了一种简单的措施，它用经济有效的方法减少扫气短路和扫气损失。在曲轴箱吸气阶段，空气被吸入扫气道上方，利用这些空气开始扫气过程。初步试验表明，在节气门全开的工作条件下，燃油消耗率约降低１０％，ＨＣ排放量约减少４０％。
Emissions from a simple vaporized crankcase scavenging two-stroke engine are primarily caused by the fresh charge lost through the vent during scavenging. These losses lead to increased fuel consumption and environmental side effects. Over the years, the use of two-stroke engines has been reduced due to emissions and fuel consumption issues. However, due to its simple structure, high power density and low production cost, it can continue to be used on mopeds, motorcycles, smallboards and small power generators. However, simple two-stroke engines are challenged by four-stroke engines because of increasingly stringent emission regulations and new regulations for many different engines. This article describes a simple measure that reduces costly scavenging shorts and scavenging losses in a cost-effective manner. In the crankcase inhalation phase, the air is sucked in the scavenging path above, the use of these air began scavenging process. Preliminary tests show that under full-throttle operating conditions, fuel consumption is reduced by about 10% and HC emissions by about 40%.