Control apparatus for pneumatic evacuation and water valves, operated by vacuum pressure

A control apparatus for pneumatically operating at least one of an evacuation valve or a water valve in a vacuum sewerage system, particularly for use in sanitary appliances, such as closets, urinals or wash basins, which are operated by vacuum, comprising:

• a housing including an activating element which is movable from an original position against a force relative to the housing to an activated position;
• a three-way control valve being disposed in the housing and comprising a valve piston and a valve disc, said control valve being operated by the activating element and transmitting vacuum from a vacuum source to the at least one of the evacuation valve or water valve while being open, the control valve being disposed in the housing and transmitting atmospheric pressure to the at least one of the evacuation valve or water valve while being closed;
• a first chamber being disposed in the housing and connected to the vacuum source and connectable to the at least one of the evacuation valve or water valve through the control valve, the first chamber disposed in the housing;
• a second chamber being disposed in the housing and in communication with atmospheric pressure when the activating element has been activated by returning to its original position after having been moved against the force into the housing, the control valve interacting with the activating element via said valve piston such that the second chamber is sealed from the atmosphere when the control valve opens, at least one of the housing or the valve piston includes a bore connecting the first chamber and die second chamber so that vacuum is continuously drawing air through the bore from the second chamber to the first chamber and creating a similar pressure in the first and second chambers when the activating element is in its original position and a differential pressure between the first and second chambers causing the three-way control valve to be moved to an activated position only when the vacuum pressure in the first chamber exceeds a predetermined value when the activating element has been activated;
• a diaphragm disposed in the housing separating the first chamber from the second chamber and being moveable for driving the valve piston of the control valve;
• and
• a spring element disposed in the housing exerting a force on the diaphragm driving it towards the second chamber, whereby the diaphragm is moved against the spring force and opens the control valve only when the pressure differential force acting on the diaphragm and resulting from a pressure difference between the second chamber and the first chamber is stronger than the spring force whereby, when the control valve is open and is in the activated position, the first chamber connects the vacuum source to the at least one of the evacuation valve or the water valve and when the control valve is closed and the activating element is back in its original position, atmospheric pressure is transmitted to the at least one of the evacuation valve or the vacuum valve to cause deactivation of the at least one of the evacuation valve or the vacuum valve.