Patent ID: 8430866

Claim:
A drainage device useable for treating patients with a pulmonary air leak, said device comprising: at least one airtight collection chamber having a first connection for a drainage tube, and a second connection for evacuation air from the airtight collection chamber; a pressure control unit connected to the second connection of the collection chamber for controlling an air pressure in the chamber; a pressure sensor capable of sensing the air pressure in the collection chamber; an air flow sensor capable of sensing a flow of air evacuated from the collection chamber; wherein said drainage device is provided with a three way valve means configured to switch between a first position where the collection chamber is connected to a suction source via the second connection and the collection chamber is disconnected from an atmosphere, and a second position where the collection chamber is connected to the atmosphere, and the collection chamber is disconnected from the suction source, and wherein said device further is provided with means for calculating, based on a pressure sensor signal from the pressure sensor, and a flow sensor signal from the flow sensor, when it is suitable to rotate the three way valve means to shift from connecting the collection chamber to the suction source to connecting the collection chamber to the atmosphere, or vice versa; a ball valve comprising a ball located and moveable between a first tube end and a second tube end, the tube ends are arranged to debouch in a common cavity, and also being arranged substantially opposite each other, and being provided with seats such that when a suction pressure is applied to one of the tubes the ball makes contact to a seat and seals off that tube and leaves the other tube open to the cavity.