Patent ID: 8029066

Claim:
A backrest assembly comprising: a front frame made of rigid material, with the front frame being annular and including front and rear surfaces spaced in a first direction, with an outer annular flange formed on the rear surface, with an inner annular flange formed on the rear surface and surrounded by the outer annular flange, defining a first annular groove between the outer and inner annular flanges, with a plurality of annularly spaced pegs formed on the rear surface and in the annular groove, with the front frame further including a plurality of first engaging holes extending in a second direction perpendicular to the first direction; a net made of bendable material and including a plurality of peg holes, with the net mounted in front of the front frame, with a periphery of the net covering the outer annular flange of the front frame and received in the first annular groove of the front frame, with each of the plurality of pegs of the front frame extending through one of the plurality of peg holes, with the net in a tightened state; a rear frame made of rigid material, with the rear frame being annular and including front and rear faces spaced in the first direction, with an outer annular wall formed on the front face of the rear frame, with an inner annular wall formed on the front face of the rear frame and surrounded by the outer annular wall, defining a second annular groove between the outer and inner annular walls, with a plurality of annularly spaced stubs formed on the front face of the rear frame and in the second annular groove, with each of the plurality of stubs including a receptacle receiving one of the plurality of pegs of the front frame, with the rear frame further including a plurality of second engaging holes extending in the second direction; and a plurality of fasteners each extending through one of the plurality of first engaging holes of the front frame and one of the plurality of second engaging holes of the rear frame.