Patent attributes
A chair has a seat, a backrest, a lift structure, a back supporting structure, and a waist supporting structure. The backrest is deposited behind the seat. The lift structure is deposited on the backrest. The back supporting structure has a bending element and multiple supporting strips. The bending element is connected with the backrest and the lift structure, and is elastic and bendable to deform. The supporting strips are deposited on the bending element at spaced intervals from a top to a bottom of the bending element. The waist supporting structure is deposited in front of the back supporting structure. The waist supporting structure has two pivoting bases and a supporting plate. The pivoting bases are deposited on the seat. The supporting plate is pivoted between the two pivoting bases, abuts the back supporting structure, and selectively abuts the backrest.