An Analysis On Statics And Dynamics As Well As Stability For The Arm Supports Of A Lift-up Fire Engine

Lift-up fire engine is an important fire fighting equipment which can eradicate fire from high-rise buildings. Along with the fast development of our country's economy, high-rise buildings increase rapidly, the fire frequency also increases day by day. So ,it's more and more urgent to develop and design lift-up fire engine.The lift-up fire engine is considered as a study objective, dynamics simulation software(ADAMS) of mechanical system is used to analyse the arm support of the lift-up fire engine and is used to analyse stability for the whole lift-up fire engine by the least remanent load on landing legs in this paper. Results obtained provide a guide in theory and design proposals for strength of the arm support and stability of the whole lift-up fire engine.In this thesis, ADAMS is introduced briefly and its theoretical basis—muti-body dynamics—is summarized in detail. A rigid model of the lift-up fire engine is built by using ADAMS. Then,considering both non-friction and friction between arm supports and pulled back and forth cylinders, the statics analysis of arm supports is made.Subsequently, in order to really simulate working conditions of the lift-up fire engine, a flexible model is built and analysed by using ADAMS. The numerical results indicate that the flexible model can actually simulate working conditions of the lift-up fire engine.Base on the flexible model of the lift-up fire engine,under the entire expanding of arm supports, the dynamics analysis of arm supports is made,vibration periods and oscillation amplitudes of hanging basket as well as dynamic moments at all arm joints are obtained.Finally, the least remanent load on landing legs is computed by spherojoints which is used to link landing legs and body.Under conditions of no gaps and gaps between pistol and cylinder, the least remanent loads on landing legs and dynamic contact force between pistol and cylinder are analyzed. Some important conclusions are obtained, which provide a reference for stability of the whole lift-up fire engine.