Optimization of the Lifting Machines’ Hoisting Mechanism Design Scheme

Increasing the productivity of lifting machines and their reliability is possible by reducing the dynamic loads that occur at the lifting mechanism starting and braking. Carried out is the analysis of methods to reduce the lifting machines’ hoisting mechanism dynamic loads during the acceleration period when load lifting. The method chosen for our study is reducing the mass inertia moments of parts located on the hoisting mechanism’s slow-speed shafts. The study aimed to reduce the hoisting mechanism dynamic loads at cargo lifting by optimizing the gear drive mechanism design scheme. One of the promising methods to reduce dynamic loads in machine drives consists of the multithreading principle use. A new design scheme for the gearbox has been developed. This structure represents a multi-threaded two-stage gearbox, where each stage consists of a central gear, intermediate wheels, which axes are fixed in the housing, and a gear wheel with internal gearing. It has been established that using intermediate wheels of different diameters can obtain different gear ratios of the gearbox. It is determined that the minimum gear ratio for a two-stage multithreaded gearbox is 9. With such a gear ratio of the gearbox, the dynamic loads that occur during the lifting mechanism drive start-up are minimal. Accordingly, the maximum efficiency of the lifting mechanism per its operation cycle was obtained. Also, the optimal gear ratio ensures the minimum dimensions of a multi-threaded two-stage gearbox.