The Development Of Forklift Gasoline Speed Limit Device

The speed limiter is an indispensable auxiliary apparatus in the internal combustion engine used in a forklift. It plays an important role in ensuring safety of forklift drivers, carried goods and hydraulic working systems of the forklift.The author analyzed the principles and existent problems of various kinds of speed limiters of forklift-used gasoline engines at home and abroad and developed a new type of pneumatic speed limiter of gasoline engines used in forklifts in this paper. This sort of speed iimiter is characterized by simplicity in structure, economy in use, and stability and reliability in performance. It solved successfully long-term existent issues in pneumatic speed limiters of high idle speed, large power loss, and swinging of speed at home by means of designing the brand-new-in-structure valve-located device梒am-spring mechanism. The match with G495, GX480 gasoline engines used in forklifts showed that this new speed limiter possessed good speed limit characteristics. The power, economy and emissions indexes of the forklift-used engines equipped with the new speed limiter meets the relevant requirements of both national and industrial standards.The author investigated the factors that influence the dynamic stability of speed limiters through both theoretical amilysis and experiments. The structural factors that affect the performances of speed limiters were discovered and corresponding improvements proposed based on optimized match experiments with 495G engines.