Adjustment device for a ski boot

Device for progressive adjustment of the relative positions of first and second elements to control the tension of a connecting element, comprising

• (a) a support (3;
• 16) solid with said first element (1) and comprising a cap shaped base (17) on which is articulated, about a horizontal and transverse axis, a cover (18) in the form of a lever having large and small branches (18a, 18b),
• (b) a rack (5) having a succession of teeth (6) of constant pitch (a), solid with said second element (2) and engaged in said support (3;
• 16);
• and
• (c) a control knob (4) rotatably mounted on said support (3;
• 16) on a lower face of said large branch (18a) above said rack (5) and having, on its lower face turned toward said rack (5) a spiral rib (15) centered on the rotational axis (xx') of said control knob (4), said control knob being biased by spring means (20) such that a portion of said spiral rib (15) is selectively engaged and disengaged between said teeth (6) of said rack (5) by pivoting movement of said cover, said spiral rib extending over an arc of at least 360.degree. and having a spacing between its turns substantially equal to the spacing between said teeth (6);
• (d) said rotational axis (xx') being inclined, relative to the plane of said rack, at an angle such that, in all angular positions of said spiral rib (15), a small portion (15a) only of the latter is engaged between successive teeth of said rack (5), while a diametrically opposite portion of said spiral rib is located above a plane passing through the crests of said teeth (6) of said rack.