Design And Experiment On Small Deep Plowing Machine Used In Tobacco Field

Most of tobacco-growing regions of Chongqing are located in the places which are more1,000meters height above sea-level.With Small plots and high ridge of field,the landfoems here have hill and mountains features.Micro tillers are now widely used in these areas because of their small size, light weight and low price. They are choosed by the majority of farmers, and They are good helpers in tobacco growing. They greatly reduce the labor intensity and significantly improve the efficiency of plowing. But these micro tillers have generally tilling depth of less than16cm. Under the surface soil, the hard bottom have formed due to micro tiller’s shallow plough year after year. The preliminary study on this situation from some soil-related professionals shows that: Firstly, microbes congregate in topsoil, which bring about serious soil-borne diseases, resulting in the incidence of tobacco seedling diseases and tobacco production cuts, even ruining; Secondly, loose layer of soil (topsoil) and compact layer of soil (hard bottom) are demarcated clearly. Thus tobacco roots generally distribute in the topsoil only. This limits the growth of tobacco roots. Tobacco can not absorb minerals and other nutrients from deeper soil; Thirdly, the loose layer of soil is too shallow, the storage capacity of water is limited, then moisture in the soil reduces. Therefore, the use of deep plowing technology to break the hard bottom is the effective method to improve the quality of tobacco growing. Now Deep plowing machines hanged and pulled by large or medium-sized tractor can achieve the demand of breaking the hard bottom, but their size and weight can not meet the working conditions of deep plowing in Chongqing Tobacco-growing regions.Aiming to the actual situation of topography and soil characteristics of Chongqing tobacco production regions, and the actual needs of the tobacco-growing, This research subject attempts to design a small deep plowing machine, which can suitable for tobacco growing areas of gentle slope hilly in Chongqing and reach more than30cm tilling depth. It will has great significance to improve tobacco production and tobacco quality in Chongqing.During the design, we adopted a arrangement of "wide upper/narrow lower" of rotary blade set, which introduces a new theory of "coexistence of deficiency and excess" into soil plowing. The transmission box is an important component of the small deep plowing machine. Machine’s work performance is directly affected by its dynamic characteristics. So the modal analysis to transmission box has a certain significance. According to the basic idea of finite element method, this paper used analysis software ANSYS10.0to analyse the modal of transmission box. Through the results,we could further optimize the transmission box.Tests in Chongqing main tobacco growing area indicated that this small deep plowing machine could reach more than30cm tilling depth and achieve the effect of "one pass/two layer, shallow plowing/deep loosening, wide upper/narrow lower, partially mixing, coexistence of deficiency and excess ". After plowing with this machine, the compact soil of lower layer and loose soil of upper layer exist at the same time, which would improve the internal environment of soil and have advantages to promote tobacco growth.