Design Of Harvesting Head For Energy Forest

At present,most of the existing cutting heads in China only have a set of sawing mechanisms,and they cannot fully utilize the ends of the energy forest trunks.With the rapid development of forestry economy and the increasing demand for wood in society,it is of far-reaching significance to optimize the mechanized harvesting operations of domestic energy forests.Based on the existing cutting head structure,this paper studies and designs a set of harvesting and collecting operation device,which is installed on the top of the existing cutting head,which can fully utilize the tip of the trunk,and can realize more than 1 to 4 clamping operations.Improve the utilization of forestry resources,the efficiency of harvesting operations and reduce the energy consumption of operations,and provide reference for future collection of energy forest harvesting.This paper firstly eonducts theoretieal research on the meehanieal structure of harvesting head,analyzes the working principle of the sawing mechanism and the auxiliary clamping mechanism,determines the maximum effective diameter of the sawing tree and the maximum working stroke and thrust of the two-mechanical cylinder,and the sawing mechanism.The structure is selected and the main design parameters of the sprocket are deeply calculated.Then,a three-dimensional model of the harvesting collection device is established to complete the virtual assembly of the device.On this basis,the kinematics simulation analysis of the device is carried out to obtain the variation of the position,velocity and acceleration of the analysis points of the auxiliary elamping mechanism with time.By analyzing the variation law of motion trajectory and speed,it can be seen that the movement of the claws on the left and right sides of the clamping mechanism is basically symmetrical,and it can be relatively stable during operation;analyzing the variation law of acceleration,it can be known that the acceleration of the clamping cylinder can be reasonably controlled.Reduce damage to trees during elamping and reduce the reaction of the knife and claws to the hinge point.Then,the device is subjected to finite element static analysis and finite element modal analysis to verify that the structural strength and stiffness are reliable.Obtaining and analyzing the resonance characteristics of the device structure provides a basis for setting the feed speed during operation,avoiding improper setting.or near resonance,and damage the device.Finally,based on the actual motion of the sawing mechanism and its performance requirements,calculate the main dimensions of the actuator,determine the hydraulic system parameters such as pressure and flow,and design a hydraulic system schematic that controls the movement of the sawing mechanism then verify the simulation.