Stabilizing jack system for portable bleacher

In a portable bleacher construction having a mobile framework for supporting a plurality of bleacher seats thereon and at least one pair of leveling jacks, wherein each pair of jacks are located on opposite front and rear sides of the framework for stabilizing the framework on a ground surface when the framework is stationary, the improvement comprising:

• at least one control arrangement located on one side of the framework, wherein each control arrangement is operably interconnected with one of the pairs of jacks and is constructed and arranged to operate each jack in the pair of jacks from one side of the framework, and wherein each control arrangement includes a pair of side-by-side manual crank assemblies mounted to an upper end of one of the jacks in each pair of jacks, each of the manual crank assemblies having a handle which is pivotable about a first horizontal axis extending generally parallel to a longitudinal axis defined by the framework, and is rotatable about a second horizontal axis extending generally perpendicularly to the first horizontal axis, and wherein each control arrangement further includes an input shaft interconnected with one of the manual crank assemblies, wherein a first one of the input shafts provides a rotary input to the jack to which the crank assemblies are mounted, and wherein a second one of the input shafts extends across the framework and provides a rotary input to the other jack in the pair of jacks.

A portable bleacher construction comprising:

• a wheeled framework for supporting a plurality of bleacher seats thereon in a mobile travel condition and a stationary seating condition;
• at least one pair of leveling jacks located on opposite sides of the framework for stabilizing the framework in the seating condition upon a ground surface, wherein each of the jacks has an upper tubular member fixed to the framework, and a lower tubular member with a ground-engaging foot telescopically received and slidably mounted in the upper tubular member for upward and downward movement relative thereof;
• and,
• a control arrangement associated with the jacks for separately controlling the leveling of both of the jacks from a common location, wherein the control arrangement includes a first rotatable crank assembly and a second rotatable crank assembly, wherein the first and second crank assemblies are movably mounted on a common side of the framework for moving the lower tubular members of both of the jacks on opposite sides of the framework upwardly and downwardly independent of each other.