Relay control interlocking door device

Disclosed is a bang-bang control interlocking door apparatus, comprising an outer door (10), an inner door (20), a master control board (30) and press keys (K1, K2) for opening the door, wherein the outer door (10) comprises a door leaf (11), a door frame (12) and an electric lock (13), the inner door (20) comprises a door leaf (21), a door frame (22) and an electric lock (23), the contact point (k1) of the press key (K1) for opening the door is connected with the actuating coil (EL1) of the electric lock (13) in series, and obtains the power from the master control board (30). The contact point (k2) of the press key (K2) for opening the door is connected with the actuating coil (EL2) of the electric lock (23) in series, and also obtains the power from the master control board (30). The device also comprises a full-locking controlling switch (K3), a fire-fighting channel switch (K4), an unlocking keyboard (40), an auxiliary controlling board (50) and an electro-acoustic transformer (60). The bang-bang control