Rapid and Accurate Stability Evaluation of Counterweight Forklift with Masts Based on Modular Dismantling Method

随着物流产业的发展，叉车作为运输物料的重要设备，具有很强的机动性和灵活性，其应用场景越来越广泛，发展前景越来越大，然而叉车稳定性不足造成的叉车事故频发，甚至严重影响货物及人身安全，迫切需要合理评估叉车在各种使用工况下的稳定性问题，为叉车事故责任鉴定及叉车安全使用提供理论支撑。本研究基于模块化拆解方法系统探究了货物特征、行驶工况等因素对平衡重叉车稳定性(横向稳定性、纵向稳定性)影响。本研究通过理论计算叉车纵向和横向所受合力矩的大小来判断其是否处于稳定状态，即理论认为M合 = M稳 − M倾 ≥ 0时叉车处于稳定状态。研究结果发现在静止或水平路面匀速运动状况下，随着货物质量的增加，叉车纵向合力矩大小逐渐减小，即纵向稳定性降低；随着货物质心偏离其中心线距离的增加，叉车横向合力矩大小逐渐减小，即横向稳定性降低。综上所述，本实验结果表明，货物重量主要通过影响叉车的纵向稳定性来影响叉车稳定性，而货物质心的偏移程度和货物质心高度主要影响叉车的横向稳定性来影响叉车的稳定性。基于上述研究结果，本研究可较好地为稳定性相关的叉车事故快速鉴定及安全使用提供基础理论数据，为叉车结构改进与安全使用贡献应用技术的支撑。As one of the most common equipment for material transportation, counterbalanced trucks with mast have remarkable mobility and high flexibility, which are applied in various scenarios with expanding developmental prospects. However, with the inadequate stability, the forklifts are prone to accidents, even more posing significant risks to both goods and individuals. It is urgent to reasonably evaluate the stability of forklift under various operating conditions to provide theoretical support for forklift accident liability identification and safe use. Based on the modular disassembly method, the multiple effects of cargo characteristics and road running modes on the stability of counterbalanced forklifts through the theoretical calculations of resultant moments in the transversal directions or the longitudinal directions have been systematically investigated in the present work. It is theorized that when the stability moment of the whole forklift is greater than the overturning moment (M = Ms − Mt ≥ 0), the forklift is in a stable state. The results revealed that the longitudinal resultant moment was decreased gradually with the increase of cargo weight when forklifts were stopped or running in a constant velocity on the horizontally surfaces. And as the distance between the cargo’s center of gravity and the centerline of pallet fork was increased, the transverse resultant moment was also decreased. In conclusion, the experimental results of this study demonstrate that the weight of goods primarily influences the longitudinal stability of the forklift, thereby affecting its overall stability. Meanwhile, the offset and height of the center of gravity of the goods predominantly impact the lateral stability of the forklift, which in turn plays a critical role in determining its overall stability. The above results could provide basic theoretical data for the rapid identification and safe use of forklift truck accidents related to stability, and contribute to the technical support for the improvement of forklift truck structure and safe use.