Crane assembly

Claim 1

A CRANE ASSEMBLY COMPRISING FIXED BOOM MEANS HAVING A PAIR OF ELONGATED CHANNEL MEMBERS DISPOSED IN PARALLEL FACING RELATION AND A C-SHAPED MEMBER EMBRACING THE TOP AND SIDES OF SAID CHANNEL MEMBERS FOR HOLDING SAID CHANNEL MEMBERS IN FIXED LATERALLY SPACED RELATION, A MOVABLE BOOM MEANS TELESCOPICALLY DISPOSED WITHIN THE FIXED BOOM MEANS HAVING A PAIR OF ELONGATED CHANNEL MEMBERS DISPOSED IN PARALLEL FACING RELATION AND BRACE MEANS HOLDING SAID LATTER CHANNEL MEMBERS IN FIXED LATERALLY SPACED RELATION, A PLURALITY OF FIRST ROLLERS MOUNTED ADJACENT THE FORWARD END OF SAID FIXED BOOM MEANS FOR ROTATION ABOUT BOTH SUBSTANTIALLY HORIZONTAL AND VERTICAL AXES, A PORTION OF THE PERIPHERIES OF SUCH ROLLERS EXTENDING INTO THE SPACE BETWEEN SAID FIRST CHANNEL MEMBERS FOR ABUTTING ADJACENT EXTERIOR SURFACES OF SAID MOVABLE BOOM MEANS, A PLURALITY OF SECOND ROLLERS MOUNTED ADJACENT THE OPPOSITE END OF SAID SECOND BOOM MEANS, A PORTION OF THE PERIPHERIES OF SAID SECOND ROLLERS EXTENDING INTO THE SPACE BETWEEN SAID FIRST CHANNEL MEMBERS FOR ABUTTING ADJACENT INTERIOR SURFACES OF SAID FIXED BOOM MEANS, SAID FIRST AND SECOND ROLLERS COOPERATING TO MAINTAIN SAID MOVABLE BOOM MEANS IN INWARD SPACED RELATION TO SAID FIXED BOOM MEANS AND PROVIDING VERTICALLY AND HORIZONTALLY ACTING FORCE COUPLES RESISTING FORCES ACTING ON SAID MOVABLE BOOM MEANS WHICH TEND TO DEFLECT SAID LATTER BOOM MEANS RELATIVE TO SAID FIXED BOOM MEANS, A DOUBLE-ACTING FLUID ACTUATOR CONNECTED BETWEEN SAID FIXED AND MOVABLE BOOM MEANS FOR MOVING SAID MOVABLE BOOM MEANS BETWEEN A RETRACTED POSITION AND AN EXTENDED POSITION, AND LOAD ENGAGING MEANS DEPENDING FROM SAID MOVABLE BOOM MEANS AND LOCATED BETWEEN AND INTERMEDIATE THE ENDS OF THE CHANNEL MEMBERS OF SAID FIXED BOOM MEANS WHEN SAID MOVABLE BOOM MEANS IS IN RETRACTED POSITION.