Study On Design And Optimization Of The Cam-type Baler Based On Hay Compression Characteristics

Hay is a vital material foundation for the development of high quality animal husbandry.China has abundant forage resources,but due to the natural distribution and degradation of grassland,it cannot be used reasonably and efficiently.The main cause for limiting the hay to be utilized efficiently is its loose nature.The most effective way to solve this problem is to compress it and increase its density.The compression process of hay has a certain regularity,existing the "loose" and "compaction" stages.At present,most of the balers in the market use crank-slider compression mechanism,in which the matching relation between compression force and speed has not been considered.Also the traditional baler is with a big size,not suitable for use in the small and hilly grassland or village.Therefore,a small cam-type hay baler is proposed in this thesis,which can realize the characteristics of the complex motion and make up for the shortage of the traditional hay baler.The features of hay in the compression process has been analyzed first,and then according to the relationship between the compression strength and the density ratio,combined with the piston stroke to determine the cut-off points of two stages,choose the appropriate pattern of follower motion was determined for designing of the cam.By optimizing the cam,the stop of the follower at the cut-off points has been solved and the working efficiency of the baling machine has been improved.The design for the rest parts of the whole baler was conducted,and the forces exerting on the main components were analyzed with finite element analysis.In Pro/E software,the 3d modeling and assembly of the parts was carried out.Finite element analysis was performed for the main force parts in the baler,and the motion for the whole baler was simulated.It is concluded that the displacement and velocity curves of the cam mechanism are matched with the compressive characteristics of the hay.The prototype was manufactured and tested.According to the analysis of the tested compression force and displacement,it proved that the cam compression device can realize the effects of compression velocity varying and the energy consumption reduction.The quality of the product is good,and the density of the bale is up to the medium density of the straw bale,proved the feasibility of the cam-type baler.