Tree shaking mechanism

Claim 1

A TREE SHAKING DEVICE FOR USE IN THE HARVESTING OF TREE BORN FRUIT COMPRISING: A RIGID POSITIONING ARM; A SHAKER HEAD MOUNTED BY AND EXTENDING FROM ONE END OF SAID ARM FOR MOVEMENT THEREBY INTO ENGAGEMENT WITH A TREE LIMB; LIMB SHAKING MEANS MOUNTED WITHIN SAID HEAD OPERABLE TO GENERATE LINEAR SHAKING FORCES IN A PREDETERMINED DIRECTION; A FIRST AND A SECOND LIMB GRIPPING JAW MOUNTED BY SAID HEAD, SAID FIRST JAW BEING MOVEABLE IN SAID DIRECTION TO GRIP A LIMB BETWEEN ITSELF AND THE SECOND JAW, AND SAID JAWS BEING ARRANGED SO THAT, WHEN A LIMB IS GRIPPED THEREBY, THE SHAKER HEAD IS ALIGNED WITH RESPECT TO SAID LIMB SO THAT SAID DIRECTION IS SUBSTANTIALLY PERPENDICULAR TO THE LIMB; A JOINT OF VARIABLE STIFNESS ARRANGED BETWEEN ANS EFFECTING THE COUPLING OF SAID ONE END OF SAID ARM AND THE SHAKER HEAD; AND MEANS FOR CONTROLLING THE STIFFNESS OF SAID JOINT WHEREBY SAID JOINT MAY BE RENDERED SUFFICIENTLY STIFF TO ENABLE THE SHAKER HEAD TO BE POSITIONED BY SAID ARM TO ENGAGE A FREE LIMB AND WHEREBY, WHEN THE LIMB HAS BEEN GRIPPED BY SAID JAWS, SAID JOINT MAY BE RENDERED SUFFICIENTLY FLEXIBLE TO ALLOW THE HEAD TO BE ALIGNED PERPENDICULARLY WITH RESPECT TO THE LIMB WITHOUT ALSO ALIGNING THE POSITIONING ARM PERPENDICULARLY TO SAID LIMB, AND WHEREBY SAID JOINT MAY BE RENDERED SUFFICIENTLY FLEXIBLE TO ALLOW THE HEAD TO SHAKE TH LIMB WITHOUT SUBSTANTIALLY SHAKING THE POSITIONING ARM.