Parameter Analysis And Improving Design Of Spring-finger Cylinder Pickup Collector

Pickup baler is one of the grass harvest machine. Spring-finger cylinder pickupcollector is the main working parts of pickup baler. Profound study in spring-fingercylinder pickup collector is most significant for improving service behavior of pickupbaler and implementing mechanized harvest of pasture. There is no definite designmethod in designing spring-finger cylinder pickup collector. In our country, theparameters of pickup collector are in imitation of foreign. We do not know the optimummatching parameters that pickup working putting into effect well. And we do not knowthe optimum cam shape with smaller leakage collecting area, proper velocity variation,less stress on parts and less power consumption of pickup collector. Aiming at theproblems, theoretical analysis, kinematics simulation and experimental test for study ofthe working process of spring-finger cylinder pickup collector are carried out. Based onthe achievement, the structure parameters and the working parameters of pickup collectorare improved.（1） Mechanism analysis of spring-finger cylinder pickup collector is charified. It is adirection changing cam mechanism with oscillating follower. The movement ofspring-finger is discussed also. Based on the discussion, the mathematical model ofspring-finger is established.（2） The chief factors to affect the function of the pickup collector are analyzed. Themain parameters to affect the function of the pickup collector are λand parameters ofcam mechanism. The value of λ is determined by heading velocity, rotational angularvelocity of cylinder and parameters of cam mechanism.（3） The moving law of cam mechanism satisfying the demand of pickup working isacquired.（4） In the course of study, a modern designing theory was introduced and a computeraided analysis to the pickup process of the pickup collector is conducted by means ofPro/Engineer designing software, ADAMS analytical software of mechanical system andhaving established a ADAMS model for the pickup implement of the collector. By goingthrough kinetics analysis, the working status of pickup collector with original parametersis required. The leakage collecting area of spring-finger cylinder pickup collector withoriginal parameters is bigger and acceleration of the end of spring-finger is larger anddiscontinuous. The essential design parameters of pickup collector are improved also.Based on the achievement, the affecting laws of the variation of each factor to the moving state of spring-finger and appropriate design method of slide track cam areacquired. Working parameters of cylinder pickup collector at given structure parametersare found. The radius of cylinder is125mm, the length of crank is80mm, the length ofspring-finger is178mm, the angle between spring-finger and crank is1.1rad, the radiusof roller is17.5mm, the quantity of spring-finger rod is5, heading velocity of pickupcollector is5km·h^-1, and rotational speed of cylinder is64r·min^-1. The cam law in liftingand returning stage is sinusoidal acceleration moving rule.（5）The acceleration testing analysis is offered with original parameters and improvingparameters of pickup collector. The result indicates that the acceleration value of the endof spring-finger reduces after improving and it is continuous. It shows that the analyticalresults of simulation are good agreed with the experiment results. This result shows thefeasibility of using simulation method to analyze the performance of the cylinder pickupcollector.（6） The pickup loss factor and consumed power with original parameters andimproving parameters of pickup collector are acquired. The result shows that the pickuploss factor after improving is reduced. Consumed power is as the same as pickupcollector with original parameters. It indicates that parameters after improving are morereasonable.（7） The overall movement process of spring-finger and material is photographed online by using the high-speed photography equipment. By going through collection andanalysis of image sequence, the relative movement law between spring-finger andmaterial agrees with the requirement of picking material. The velocity of spring-fingervaries reasonable and the acceleration of spring-finger is continuous. It shows that thesimulation results are agreed with the experiment results.