Spring supports

A spring support of the constant spring force type comprising:

• a frame having an elongated slot;
• a series of locating formations along a longitudinal edge of said frame slot;
• suspension means for suspending said frame from a support for use and including a suspension carrier which engages in and is shorter than said frame slot, has key means engageable with said locating formations, is set in said frame slot at any selected one of a plurality of positions along said frame slot determined by said locating formations and is located in said selected position by interengagement of said key means with said locating formations;
• a lever pivoted to said frame and having an elongated slot extending radially of said lever pivot and laterally opposite said frame slot;
• a series of locating formations along a longitudinal edge of said lever slot;
• a load carrier for connecting a load to said lever and which is engaged in and is shorter than said lever slot, has key means engageable with said locating formations of said lever slot, is set in said lever slot at any selected one of a plurality of positions along said lever slot determined by said locating formations of said lever slot and at varying distances from said lever pivot, and is located in said selected position by interengagement of said key means of said load carrier with said locating formations of said lever slot;
• a draw bar attached to said lever;
• spring means acting on said draw bar and applying on said lever, through said draw bar, a force which counterbalances the load supported by said load carrier on said lever in use;
• a component associated with said spring means being connected to said draw bar, movable with said draw bar in the direction of longitudinal movement of said draw bar, and normally urged by said spring means away from said lever, and having parts which project laterally of said spring means and are diametrically opposed with respect to the axis of longitudinal movement of said draw bar;
• a fixed part on said frame;
• locking means which acts between said spring means and said fixed part for locking said spring means against movement in the direction of longitudinal movement of said draw bar, and thereby effectively locking said draw bar and lever against movement, said locking means comprising two elongated externally threaded members and nuts threadedly engaged with said threaded members, said threaded members being fixed to said fixed part and extending alongside said draw bar at corresponding diametrically opposed positions to said projecting parts of said component, said projecting parts freely cooperating with said threaded members, and said nuts being movable on said threaded members at opposite sides of said projecting parts between released positions in which they are spaced from said projecting parts and leave said component, and thereby said spring means, free to move longitudinally relative to said threaded member, and locking positions in which said nuts are tightened against said projecting parts to prevent said component from moving relative to said threaded members and thereby lock said spring means against longitudinal movement.