Patent ID: 6988592

Claim:
An elevator system comprising: an elevator opening; an elevator hall door for closing and opening the elevator opening on an elevator hall, said elevator hall door comprising: a door panel comprising a surface board for facing the elevator hall, a back board for facing the elevator opening, and a reinforcing member for reinforcing said surface and back boards; and first and second fasteners configured to connect said back board to said surface board or said reinforcing member, wherein at least a part of said second fasteners is configured to lose the force of constraint against said surface board or said reinforcing member on high temperature conditions during a fire prior to said first fasteners losing the force of constraint; wherein said first fastener comprises a steel rivet of a steel product for connecting one end portion of said door panel, and said second fastener comprises a low-melting-point or low strength aluminum rivet of aluminum for connecting the remaining portion of said door panel to be used as said connecting member.