AIR SUSPENSION SYSTEM

An air suspension system is provided to prevent failure or damage to the system due to overheat when switching valves are kept on for a long time by operating on/off of the switching valves alternately and discharging compression air to two paths alternately. An air suspension system comprises air springs(120), spring opening and closing valves(125), an air tank(140), a compressor(160), first, second, and third switching valves(162,164,166), and vent valves(130). Compression air is stored up in the air tank. The compressor is placed between the air spring and the air tank. The first switching valve communicates with the air springs and with an input end(160a) and an output end(160b) selectively. The second switching valve opens and closes a path between the input end of the compressor and the air tank. The third switching valve opens and closes a path between the output of the compressor and the air tank. The vent valves are connected with the first switching valve and the air spring to control the discharge of the air. The compression air stored in the air tank passes through a path connected with the second and first switching valves and passes through a path connected with the third and first switching valves.