Abstract: The vaccum-operated draining system comprises a vacuum source (12), a manifold (14,16) connected thereto and a plurality of connecting conduits (22) connected thereto which are respectively closeable by a suction valve (24). To stabilize the vacuum available on the connecting conduits, thereby safe-guarding the operation of suction valves controlled in response to pressure, provision has been made that the manifold (14,16) between the connecting conduits (22) and the vacuum source (12) is continuously inclined and is dimensioned such that the inner cross-section thereof also at peak loads, in part, is clear.

Abstract: The coupling for a vacuum fluid line has a tubular first coupling part (10) that can be axially inserted with radial play into an annular groove (14) in the frontal face of a bushing-shaped second coupling part (12) until it reaches a tight contact position and can be locked in this position. In order to facilitate and to be able to better control the release of the coupling, it is provided that on one of the coupling parts (10,12) a separation ring (24) is positioned in an axially fixed but rotatable manner. It has a cam-shaped lateral surface (34) that supports itself on a counter-surface (36) attached to another coupling part (10) and pushes apart the two coupling parts (10,12) by wedge action when the separation ring (24) is rotated.

Abstract: A diaphragm-type check valve for vacuum pipes is provided which enables opening of the valve using substantially less operating force than is required in conventional valves of the same size and type. The valve includes a flexible diaphragm which is disposed in the pipe and is held in its closed position by the vacuum in the pipe. A mechanical operator such as a vacuum-actuated piston causes opening of the valve. A cavity located on the side of the diaphragm opposite that which is exposed to the pipe vacuum is selectively connected to a source of suction or vacuum (preferably that provided by the pipe itself) so as to substantially equalize the pressure on both sides of the diaphragm and thereby enable opening of the valve with a less bulky operating mechanism that provides only the reduced operating force referred to above.

Abstract: For a pneumatically driven drainage facility, an intermediate station for receiving and boosting the liquid and air through the system. This intermediate station comprises a tank with an inlet for receiving the air driven liquid such that the liquid collects at the bottom of the tank. A first branch line communicating with the tank above the surface of the collected liquid extends outwardly from the tank for the passage therethrough of air which has entered the tank. A second branch line leads from the tank for delivering the collected liquid, a pump being provided for passing the liquid from the tank into the second branch line. The two branch lines join again at a point downstream from the tank in a descending conduit section, the first branch line entering the descending conduit section downstream from the entry therein of the second branch line. The descending conduit section ends with a U-shaped adjoining pocket.

Abstract: A vacuum drain system having alternating ascending and descending sections in a conduit for conveying a liquid, such as waste water, to a collector tank maintained under vacuum to induce liquid flow through the conduit. At least one of the descending conduit sections is of larger cross section than an adjacent ascending section to facilitate flow of liquid through the conduit.

Abstract: A backwater tank system is provided for a building connected to a vacuum drain facility wherein the waste water of the building is drained off by gravity feed lines into a collector which is connected to a vacuum drain conduit by means of a pneumatically controlled check valve that opens automatically at a specific maximum water level, and wherein a ventilated backwater tank is connected to the gravity conduit or the collector at a level above the maximum water level in the collector, the capacity of the backwater tank being large as compared with that of the collector. The check valve and the pneumatic control devices therefor are disposed in or on the tank outside the main chamber thereof and preferably in an auxiliary chamber in the tank. The tank, check valve and control device form an integrated pre-assembled unit which includes an inlet connection adapted to be connected to the gravity feed line.