Experimental studies of the operation of a gripping and cutting device with a vibration mechanism

The article presents the results of experimental studies of changes in the pressure of the vibration and tree clamping mechanisms of the gripping and cutting device at different stages of the technological process of thinning. The studies were conducted on an experimental sample of the gripping and cutting device with a vibration mechanism. As part of the experimental studies, the gripping and cutting device performed the main technological operations of logging, such as cutting and gripping a tree, separating a tree from a stump and dynamic stabilization in a vertical position during transportation. When performing technological operations, the parameters of the harvested trees varied in diameter at the cut site. Birch was chosen as the main harvested tree species. To identify the nature of the loads exerted, pressure changes in the lines of the drive hydraulic cylinder of the clamp lever and the hydraulic motor of the vibration mechanism were recorded using measuring sensors. The data obtained showed that when the vibration mechanism starts working, there is a surge in the amplitude and frequency of pressure oscillations in the lines of the vibration mechanisms and tree clamping, which is associated with the kinematics features of the gripping and cutting device design and strong swinging of the cantilever-mounted tree. It was also established that in the steady-state mode of operation of the vibration mechanism for trees from 10 to 16 cm at the cutting site there was a tendency to reduce the amplitude and frequency of pressure oscillations, which indicates to us the desire of the system to stabilize and smooth out dynamic parameters. Analysis of experimental data on harvesting trees of different diameters showed that the value of pressure in the main lines of the clamping and vibration mechanisms is within acceptable limits and with further improvement of the design of the gripping and cutting device with a vibration mechanism, there is a possibility of increasing the efficiency of dynamic stabilization of the tree in a vertical position.

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