Electric Pruning Shear
What to Fix
Project Description: In the fruit growing industry, pruning back growth is a delicate, time consuming and costly part of annual routine. Because of the number of trees to be pruned and the length of time that the worker operates, the pruning device’s weight and efficiency are at a premium.
The functional cutting head, at the tree branch, is to be re-engineered for reduction of overall power usage. This will minimize the weight needed for batteries and limit user fatigue. The Pellenc TreeLion (pictured below) is arguably a poor attempt at solving these problems, and an expensive one. The problems to be solved are, as follows.
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Project Requirements:
• Cutting head must weigh less than 1 lb. (see Appendix A-4)
• Must not exceed a 3-inch radius from the axial center line of the shaft.
• Must not dull during the 1 day’s usage (HRC 57-62.)
• Must not create torsional roll < 1-inch limb in between blade and anvil.
• Using the rake and clearance, must produce a linear power graph.
• Have a blade opening of less than 4 inches.
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Customer stipulates that it must cut through 1-1.75-inch diameter fruit-wood limbs (Green and Dry.)
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Being roughly 1/3 of the engineering burden, Must cost less than 1/3 of the total Pellanc system at $1333.33.
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Must reduce the total cutting force by greater than 10%.
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Must complete a comparable cutting function using 10% less energy.
