Folding chair

A folding chair, which can be maneuvered between a folded position and an unfolded position, including:

• a tubular structure made up of two units each comprising first and second tubes hinged on one another by a hinge pin, the axes of the two units being coaxial, each first and second tube comprising an upper segment and a lower segment, the upper segments of the first two tubes forming a seat back and the lower segments of the first two tubes forming a front leg assembly, the upper segments of the two second tubes forming a seat bottom and the lower segments of the two second tubes forming a rear leg assembly,
• a canvas sheet mounted on the upper segments of the first tubes on the one hand, and on the upper segments of the second tubes on the other hand,
• wherein each assembly of two tubes comprises a rigid part at the hinge pin thereof, said rigid part being arranged between the two tubes, and having:
• a groove in the shape of a segment with a cylindrical surface designed to receive, with no degree of freedom, a tube of the assembly of two tubes, an orifice for the passage of the hinge pin emerging in the bottom of the groove of the central zone thereof,
• first and second cradles in the form of segments with cylindrical surfaces with the same axis and same curve radius, positioned separated from each other on either side of the hinge pin, the axis of the first and second cradles forming an angle with the axis of the groove, the first cradle being turned upward, and the second cradle being turned downward, such that when the chair is in the unfolded position:
• the first cradle bears against the upper segment of the other tube of the assembly of two tubes, and
• the second cradle bears against the lower segment of the other tube of the assembly of two tubes.