The utility model provides a mechanical automatic drainer which comprises a storage
assembly, a floater and a plurality of drainage assemblies, the storage
assembly is provided with a drainage port and a ventilation port, each drainage
assembly comprises a
branch pipe, a sliding sleeve, a
siphon and a cover plate, and the bottom end of the
branch pipe is provided with a water inlet hole. The cover plate is connected to the water inlet end of the
siphon in an openable and closable mode through an elastic piece. Therefore, when the floater ascends along with the liquid level, the sliding sleeve is driven to slide upwards, the sliding sleeve drives the cover plate to be opened and communicated with the water inlet end of the
siphon, the storage assembly is in a drainage state, and when the liquid level is higher than the top of the siphon, accumulated water is gradually drained under the siphon principle, and the self-drainage effect is achieved. When the floater descends along with the liquid level, the sliding sleeve is driven to slide down and be separated from the siphon, the cover plate seals the water inlet end of the siphon under the elastic action, the storage assembly is in an air storage state so as to avoid
compressed air leakage, the whole process is in mechanical cooperation and does not depend on manpower and electric appliances,
automation is high, drainage timeliness is guaranteed, and the
system operation stability is guaranteed.