Design And Optimization Of Three-arms Rotary Vegetable Plug Seedling Pick-up Mechanism

In the past few years,with the enlarging planting area of the vegetable,the enhancing support of national agriculture policy and the increasing demand of vegetable market,the development tendency of vegetable industry seems promising.Besides,an increasing number of agricultural labour force are shifting into cities due to the improvement of economic and cultural levels.Under the Circumstances,calling for improving the mechanization level of vegetable production is rising.It's reported that semi-automatic transplanter is still the main stream of our country,which manually picks up the plug seedlings and plants them by mechanism.Generally,it can only pick up 30 plug seedlings per minute in one row.As for automatic transplanter,its pick-up work is carried out by mechanism,which can alleviate the labour intensity and improve agricultural productivity.In the very near future,automatic vegetable transplanter will be the main potential trend of mechanization of vegetable industry.Therefore,it's useful for our development of automatic vegetable transplanting mechanism to design a high efficiency and high speed pick-up mechanism.A new three-arms rotary vegetable plug seedling pick-up mechanism has been developed on the basis of design experiences about current pick-up mechanism.It's capable of picking up vegetable plug seedling automatically with high efficiency and speed.What's more,it has compact structure and can transmit smoothly.By far,it has been applied for a practical new-type patent and accepted.A kinematic aided analytical and optimal software of this mechanism also is developed and granted for its full copyright.The main content of this paper is as follows.1)Comparing among two-arms,three-arms and four-arms designs,a three-arms rotary vegetable plug seedling pick-up mechanism is chosen after taking the pick-up efficiency and structural size into consideration.2)A kinematic theory model is established after detail introduction on the theory of modified elliptical gear drive and a computer aided and analytical software on the three-arms rotary vegetable pick-up mechanism is developed Under objectives of parametric optimization,a series of optimal parameters,which can achieve picking-up objective,is obtained:?=26.869mm,k=0.991,?₀=64°,?=275°,?₀=35°,S=152mm,?₀=24°3)Based on gear enveloping theory,a new tooth profile generation method of conjugate non-circular modified elliptical gear is developed,which can be achieved by the combination of VB and AutoCad.4)After creating the 3D model of the three-arms rotary vegetable plug seedling pick-up mechanism,a dynamic simulation is conducted.What's more,its prototype is used to carry out a pick-up test for the correctness and the feasibility of its design.Besides,it turns out that the goal of picking up with high efficiency and speed is achieved,which can pick up 120 vegetable plug seedlings in a minute for one row.