Elevator air supply system and method

The invention discloses an elevator air supply system and a method. The elevator air supply system comprises an air supply device, an air supply channel, a mechanical shaft ramp and an air inlet, wherein the air supply device communicates with natural air; the air supply channel is arranged in an elevator shaft and communicates with the air supply device; at least one air supply opening is formedin the air supply channel, and a mechanical air valve is arranged at the position of each air supply opening; the mechanical shaft ramp and the air inlet are arranged on an elevator car, and the mechanical shaft ramp can open and close the mechanical air valve; and when the elevator car passes through one air supply opening, the mechanical air valve can be opened and closed under the action of themechanical shaft ramp so as to supply the outside air into the car or stop the air supply. According to the elevator air supply system and the method, an elevator ventilation system can be shared with a building fire-fighting