Hydraulic Power Consumption and Pressure Factors for Trunk Shaking Cherry Trees
1988; American Society of Agricultural and Biological Engineers; Volume: 4; Issue: 4 Linguagem: Inglês
10.13031/2013.26622
ISSN1943-7838
AutoresH. A. Affeldt, G. K. Brown, G. R. Van Ee,
Tópico(s)Electrical Fault Detection and Protection
ResumoLARGE relative displacements between a cherry tree trunk and a trunk shaker clamp pad can result in pressures on the bark which can crush internal trunk tissues. Start-up and shut-down of a commercial trunk shaker typically caused large displacements resulting from low natural frequencies of the tree and shaker, thereby inducing resonance. Elapsed time to reach full mass frequency varied from 0.6 to 1.2 s with all peak circuit pressures occurring during the first 2 s of valve opening. Pressures were highest under no tree and small tree conditions. Resonance, excessive displacement, and excessive stress might be avoided if elapsed time to full frequency can be reduced by a closed-center pressure-compensated hydraulic circuit, but field tests are needed to evaluate real behavior.
Referência(s)