A gas-tight device used on a manned spacecraft for astronauts to enter or return from space. The pressure chamber cabin has two pressure chamber doors, one is connected to the sealed cabin, called the inner door, and the other is the outer door that can lead into space. The door can be opened and closed electrically or manually.
The pressurized chamber cabin is equipped with a door console, an air supply and exhaust device before opening the door, communication and lighting equipment, and aerospace suits worn by astronauts when exiting the cabin. The opening and closing of the door must be very careful and skillful to avoid the danger of air leakage. Before leaving the cabin and entering space, astronauts must wear aerospace suits in the cabin.
After exiting through the inner door, close the inner door and exhaust the cabin air from the decompression chamber into the cabin. Only when the pressure in the cabin is equal to the outside space Open the outside door to enter the space. . When the astronaut returns to the decompression chamber cabin, the operation is performed in reverse order: close the outer door and pump air from the cabin into the decompression chamber cabin.
When the two pressures are equal, open the inner door and the astronaut can enter the cabin. The tightness of the inner and outer doors is absolutely reliable, which is the basic condition of the airlock cabin. The manned Soviet spacecraft “Ascent” 2 first used an airlock capsule, which was used by astronaut Α.Α Leonov to get out of the capsule and go into space.