Study On A New Electromechanical Retarder

With the rapid develop ment of auto motive techno logy a nd continuo usimprovement of the road, vehic le speed are genera lly increased, people haveincreasingly higher demands on vehic le safety. Especia lly for the frequent stop citybuses and heavy trucks driving on the mountain, the proble m of too muc h brake loadbecomes more and more pro mine nt and serious, if a ll these brake load was borne bythe ma in brake syste m of the vehic le, it will cause that friction plates become very hot,and then therma l fade pheno me non will happen, these will serio usly a ffect vehic lesafety.New electromechanical retarder, whic h is a new type of the auxiliary brakingdevice, insta lls on the ve hic le,it ca n not only e nable the main brake systems toextreme ly reduce the brake temperature, but also enhance the vehic le’s brakingperformance and security.At the beginning of this paper, s ignificances of research and developme nt of newretarders and prospects are analysed, essentia ls for insta lling retarders on domesticcar are disc ussed, especia lly for the large-sca le passenger cars and Overloadedvehic les.Domestic and foreign regulations specified to the retarders aresummarized,the required work conditions o f the electro mechanica l retarder isident ified,the advantages and disadvantages of electromechanical retarder areconc luded. After making a detailed comparison amo ng electromec hanica l retarder、Eddy-current retarder and hydraulic retarder,the develop ment s ignificances of theelectromechanical retarder are affirmed.The mathe matical models of the electromechanical retarder is put forward bymak ing a ana logous ana lys is between electromechanica l retarder and other traditiona lbrakes，the mathe matical models o f main components of e lectromechanical retarderare analysed and establis hed, including frictio n drum, brake, frictio n, gear and otherparts.Design and check ana lys is for ma in components of electromechanica l retarderare finished.finally, the specific model of the new electromechanical retarder isachie ved.Using finite ele me nt software for the process of simulation o f the brake, thefriction s urface pressure distributions are obtained,the different pressure distrib ut ionsbetween the simulation results and traditio nal theory are discussed in more detail,thebrake drum and brake shoes of stra in and stress fie ld are also acquired, Those finiteele ment calc ulation results are further discussed. During Thermodyna mic analys is, brake working conditio n on long slope atconstant speed is ana lysed,this cond ition can mostly prove the performa nce of a llkinds of retarders.Heat flux model of new e lectromechanica l retarder is established，transie nt finite eleme nt calculated temperature distributio n and thermal stressdistribut ion are discussed in more detail.Finite e le ment analysis of products have become an important process during theproduct design cycle, calculatio ns and ana lys is for the design para meters andperformance analysis enable to reduce product development c ycle and optimizeproduct performa nces.In this paper, the acquired finite ele me nt ana lys is results of theelectromechanical retarder provide a theoretical foundatio n.