Tube lifter with ventilation valve

A ventilation valve for a tube lifter, comprising

• a negative pressure side,
• a ventilation side, in particular connected to the atmosphere,
• a valve mechanism for opening and closing a flow connection between the negative pressure side and the ventilation side,
• characterized in that the valve mechanism comprises a first valve body device with at least one first valve body and a second valve body device with at least one second valve body
• the first valve body device being adjustable in a first switching direction proceeding from a closed position to an open position,
• the second valve body device being adjustable in a second switching direction proceeding from a closed position to an open position,
• the valve body devices being motion-coupled to one another in such a way that when the first valve body device moves in the first switching direction the second valve body device moves therewith in the second switching direction and vice versa,
• the valve mechanism, in particular the valve body devices being designed such that, when there is a pressure difference between the negative pressure side and the ventilation side, at least in the closed position, a first force acting in the first switching direction is exerted on the first valve body device and a second force acting counter to the second switching direction is exerted on the second valve body device the valve mechanism, in particular the valve body devices being designed such that the first force and the second force differ from one another in terms of amount by a maximum of 10%, preferably a maximum of 5%, more preferably a maximum of 1%, in particular are identical.