Mobile work platforms

Claim 1

AN ARTICULATED BOOM-ASSEMBLY COMPRISING A BASE, AN UPSTANDING SUPPORT MEMBER OPERATIVELY MOUNTED ON THE BASE FOR ROTATION ABOUT AN UPRIGHT AXIS WHICH IS SUBSTANTIALLY PERPENDICULAR TO THE BASE, A FIRST BOOM OPERATIVELY MOUNTED ON THE UPPER END OF THE SUPPORT MEMBER FOR PIVOTING ABOUT A FIRST PIVOT AXIS WHICH IS SUBSTANTIALLY PERPENDICULAR TO THE UPRIGHT AXIS OF THE SUPPORT MEMBER, FIRST POWER ACTUATED MEANS OPERATIVELY CONNECTED BETWEEN THE FIRST BOOM AND THE SUPPORT MEMBER, SAID FIRST POWER ACTUATED MEANS INCLUDING TWO LINKS WHICH ARE PIVOTALLY CONNECTED AT ONE END TO EACH OTHER AND ARE SWINGABLY CONNECTED AT THEIR OTHER ENDS TO THE FIRST BOOM AND SUPPORT RESPECTIVELY SO AS TO STRADDLE THE FIRST PIVOT AXIS, SAID LINKS BEING CONJOINTLY CONNECTED FOR PIVOTING MOVEMENT TO THE FIRST POWER ACTUATED MEANS SO AS TO HOLD SAID MEANS IN LATERALLY OFFSET RELATION TO SAID FIRST PIVOT AXIS, WHEREBY TO SWING SAID FIRST BOOM FROM A SUBSTANTIALLY HORIZONTAL POSITION TO AN UPRIGHT POSITION THROUGH AN ARC SUBSTANTIALLY IN EXCESS OF 90*, SAID FIRST BOOM BEING PROVIDED AT ITS OUTER END WITH A FIRST HINGE-FORMING BRACKETELEMENT WHICH CARRIES PIVOT-FORMING MEANS HAVING A PIVOT AXIS SUBSTANTIALLY PARALLEL TO SAID FIRST PIVOT AXIS AND LOCATED OUTWARDLY AND UPWARDLY FROM THE OUTER END OF THE FIRST BOOM WHEN THE FIRST BOOM IS IN SAID HORIZONTAL POSITION, A SECOND BOOM ADAPTED TO ASSUME AN OVERLYING POSITION IN RELATION TO THE FIRST BOOM WHEN SAID FIRST BOOM IS IN SAID HORIZONTAL POSITION, SAID SECOND BOOM HAVING AN INNER END AND AN OUTER END, SAID SECOND BOOM BEING PROVIDED AT ITS INNER END WITH A HINGE-FORMING BRACKETELEMENT WHICH CARRIES PIVOT-FORMING MEANS LOCATED DOWNWARDLY AND OUTWARDLY FROM THE INNER END OF THE SECOND BOOM WHEN THE SECOND BOOM IS IN OVERLYING POSITION WITH RELATION TO THE FIRST BOOM, THE PIVOT-FORMING MEANS OF THE SECOND BOOM BEING OPERATIVELY ENGAGED WITH THE PIVOTFORMING MEANS OF THE FIRST BOOM WHEREBY TO ESTABLISH ARTICULATED CONNECTION BETWEEN SAID BOOMS ABOUT A SECOND PIVOT AXIS WHICH IS PARALLEL TO THE FIRST PIVOT AXIS, SAID BRACKET-ELEMENTS BEING ADAPTED TO FIT WITHIN ONE ANOTHER