Abstract: A chair, particularly an office chair, comprises a chair column, a seat lower frame supported on the chair colunm in a height-adjustable manner and rotatable relative to a vertical axis, a seat support supported on the seat lower frame turnably about a horizontal axis, a backrest support supported on the seat lower frame turnably about a horizontal axis, at least one spring with adjustable tensioning and supported on the seat lower frame and the backrest support, an adjustable abutment provided for the pressure spring, a control curve against which the adjustable abutment abuts, and an adjusting element arranged to displace the control curve.

Abstract: A supporting device is disclosed for an arrangement of articulated elements such as a fin-rudder arrangement, wing-trailing edge flap arrangement, and the like, for aircraft or watercraft. The disclosure more particularly relates to the cover for the gap existing between the two articulated elements. There is disclosed an arrangement of levers and bearing points which allow the cover to maintain a constant length and approximately constant curvature over its length as the two elements move relatively to each other. The arrangement of the disclosure eliminates corners and folds in the elastic cover without also requiring parts protruding beyond the elastic cover and without requiring high forces to deflect the cover.