Abstract: A dental patient chair is provided with a backrest which is arranged inclinably with a backrest carrier on a seat and is adjusted toward and away from the seat so that the backrest carrier and seat are each, respectively, provided with a curved path in which appropriate guide elements are allocated. As a result, the backrest carrier is moved under the seat when the backrest is inclined backward and, in turn, is withdrawn from within the seat when the backrest is moved forward to an upright position. In order to achieve an optimum motion sequence of the backrest, the curvature of the two curved paths of the seat and the backrest are designed so that the momentary pole around which the backrest turns when being inclined is not constant but, on the contrary, moves on a section of a spiral curve which preferably opens upward and proceeds in the same direction as the incline motion of the backrest.

Abstract: A dental patient chair has an adjustable headrest on a headrest carrier. The headrest is pivotably hinged around a transverse first axis on a bracing member which, in turn, is adjustable in the longitudinal direction in the backrest. In addition, the headrest is connected by a linkage which is pivotably connected on a second axis offset from the first axis so that movement of the linkage causes tilting of the headrest. The linkage is shifted as the headrest carrier is extended and contracted.