This invention relates to a device for controlling the flex of ski and the like boots.
It is a well known fact that a currently much felt problem in the ski boot industry is that of providing a selectable form of flex adjustment for a ski boot, because the extent of the flex directly affects in practice the effort required to lean the skier's lower leg portion forwardly.
U.S. Pat. No. 3,686,778 discloses a ski boot which is provided, located between the boot shell and cuff, with elastic means for controlling the swinging movement of the cuff relatively to the shell in a back and forward direction, which means comprise, for example, a hydraulic cylinder connected to the boot shell, wherein a piston is movable the rod whereof is linked to the cuff portion.
The piston is provided with a throttling means, made adjustable through a rod which is accessible from the outside, which means affords the possibility of varying the extent of the elastic bias by creating a greater or lesser opposition to the fluid flowing from one into the other of the chambers defined by the piston inside the cylinder.
The fluid is caused to flow through the cylinder, both because of forward leaning and rearward leaning of the cuff with respect to the shell.
With that approach, it occurs that the fluid, being forced to flow through the throttled or necked down port defined in the piston, affords no suitable action for the achievement of a differentiated opposition to the forward lean and rearward lean movements, so that it is impossible to adjust the two bias forces independently of each other.