Vacuum pump has a protective membrane over the drawing zone, and a safety valve to prevent membrane damage through condensation at the membrane and overpressure within the drawing zone

摘要

The vacuum pump (1) has a protective membrane (2) with its inner side against a drawing zone (7), which is linked to an evacuation zone through a valve (9) at the suction side and is coupled to the pump outflow through a valve at the pressure side. An overpressure valve (11) is between the drawing zone and the suction side of the vacuum pump linked to the evacuation zone. The valve opens in the event that there is a given overpressure within the drawing zone against the ambient pressure on the outer side of the membrane, to give pressure compensation between the drawing and evacuation zones. The membrane is coupled to a push rod (3) for the pump movements, and the overpressure valve is a spring-controlled non-return valve.