A tree limb is vibrated to shake the fruit therefrom. A small lightweight internal combustion engine, such as is used for power saws, is used and it is isolated from the boom by a spring and the boom is isolated from the tree engaging finger by a second spring, thereby permitting the boom and limb to have a greater amplitude of movement than the reciprocating exciter of the engine assembly and also the limb engaging finger can move with respect to the boom to accommodate for different angles. The speed of the engine is adjusted to the natural frequency of the limb at which point the limb will have a large amplitude of vibration.
CROSS-REFERENCE TO RELATED APPLICATIONS
On June 23, 1970, I filed application Ser. No. 49,078 for Apron for Fruit Harvesting, which, together with the Limb Shaker disclosed herein, works together as a unit for harvesting the fruit.
A portable device for shaking the branches of trees to dislodge fruits or nuts, has a drive motor which is coupled to a reciprocatable rod through a gear transmission including a centrifical clutch and a linkage including a ball and socket joint incorporating a needle bearing, a hook shaped member on an extension rod being detachably attachable to the reciprocatable rod.
The low power agricultural mechanical tree shaker for fruit harvesting using phase-controlled linear impact vibrations includes an adjustable springs set (FIG. 3) (8) that connects the vibrator set (FIG. 1) (1) to the clamp/trunk or limb set (FIG. 1) (4) (FIG. 5) through the guiding system (FIG. 3) (9, 10, 18, 19) and allows to set the spring tension for resonance vibration after attaching the shaker to a particular tree. Consequently, the vibration of the shaker set will have an adjustable phase angle between the shaker set and the clamp/trunk or limb set, between 0.degree. and 360.degree.. The clamp has the form of a fork (FIG. 5) and includes a set of vulcanized asymmetric grips (FIGS. 3 and 5) (15), a vulcanized chains set (FIG. 5 (17), for the attachment of the clamp to the tree.
A vibration mechanism (300) for shaking a tree trunk held between two clamps, for an efficient harvest of the tree-fruits and for preventing damage to the tree-roots and to the tree trunk. The vibration unit comprises two counter-rotating rotors (R) weighted by displaceable weights (18, 19) and powered, preferably, by at least one hydraulic motor (M). A transmission (T) coupled to the motor and to the rotors, counter-rotates the rotors.
A tree-shaking apparatus that includes a pair of vibration units whose eccentric rotators turn at identical speeds but in opposite directions. During operation, rotation of the eccentric members is coordinated by a controller such that their asymmetric portions align at two diametrically opposed points but lie precisely out of phase during the remainder of the rotation cycle. This action causes the tree to shake along a single axis, specified by the chosen alignment of the rotators, with vibratory forces along all other directions canceling out. A controller systematically alters the direction and frequency of shaking and monitors the resulting change in vibration amplitude, selecting, as a final shaking axis and frequency, those which correspond to the largest amplitude.
A tree-shaking apparatus includes a vibration mechanism of conventional design mounted on a movable, tilted frame support that serves to deflect falling harvest onto a conveyor and collection assembly, which is mounted on a separately movable frame support. The shaking and collection units are brought separately to the tree, and unite with one another by means of rods that interlace during operation. In one embodiment, the rods associated with the shaking and deflection unit are selectibly extendible, while those associated with the collection unit flip into place and, upon completion of harvesting, flip back, thereby tipping any remaining harvest onto the conveyor.
