Abstract: An inlet valve for regulating the pressure at the inlet channel of a vacuum pump comprising: a first chamber defined by a housing having at least one inlet channel connected to a first supply of a fluid, comprising a movable element defining two cavities fluidly sealed from each-other and means for exerting a force on the movable element; a second chamber separated from the first chamber by a wall and defined by a housing, being in direct communication with a process channel of a second supply of a fluid; a valve body slidably mounted in the wall to prevent a fluid flow between the second chamber and the second cavity of the first chamber, the valve body having a distal end and a proximal end, wherein the valve body comprises a fluid channel extending through the valve body allowing a fluid flow between the first cavity and the inlet channel.

Abstract: Liquid Ring pumps are inherently inefficient due to energy losses caused by friction, the present invention overcomes this by providing a coating on certain surfaces of the pump to limit the friction.

Abstract: An inlet valve for regulating the pressure at the inlet channel of a vacuum pump comprising: a first chamber defined by a housing having at least one inlet channel connected to a first supply of a fluid, comprising a movable element defining two cavities fluidly sealed from each-other and means for exerting a force on the movable element; a second chamber separated from the first chamber by a wall and defined by a housing, being in direct communication with a process channel of a second supply of a fluid; a valve body slidably mounted in the wall to prevent a fluid flow between the second chamber and the second cavity of the first chamber, the valve body having a distal end and a proximal end, wherein the valve body comprises a fluid channel extending through the valve body allowing a fluid flow between the first cavity and the inlet channel.