Seat, especially work seat, with several positions

Claim 1

Seat, especially work seat, comprising a frame mounted vertically adjustable on a support base and carrying a body-supporting structure including a substantially flat front seat portion, a curved rear seat portion and a back rest portion, a curved bracket having a lower front end and an upper rear end on the frame for supporting the back rest portion, the front seat portion having a front end and a rear end and being pivoted near its front end by a first horizontal transverse axis to the frame near the front end thereof and at its rear end by a second horizontal transverse axis to the front end of the rear seat portion, the bracket being pivoted at its lower front end by a third horizontal transverse axis to the frame, in front of said second axis, a positioning means provided having one portion attached to the bracket between the two ends of the bracket another portion attached to and the frame for maintaining the bracket in several positions with respect to the frame around the said third axis, the back rest portion having an upper end and a lower end and being pivoted between the said two ends by a fourth horizontal transverse axis to the upper rear end of the bracket and at its lower end by a fifth horizontal transverse axis to the rear upper end of the rear seat portion, and the rear seat portion being flexibly connected, between the said second and the fifth axes, by a non-rigid connection to the bracket so that the body supporting structure can be brought into a forward position in which the front end of the rear seat portion and the front seat portion are slightly inclined forwards and downwards relative to the horizontal, and into a draw-back position in which the front end of the rear seat portion and the front seat portion are inclined rearwards and downwards relative to the horizontal.