Vacuum drainage system
AssigneeAB Electrolux
InventorHarald R. Michael
Life of this patent
Estimating the term…
Abstract
A vacuum drain system including a collecting tank and a sewage drain vacuum conduit line for conveying sewage from service connections to the collecting tank under the influence of vacuum in the system. Each service connection for admitting sewage includes a suction valve which also admits a volume of air to facilitate movement of sewage in the system. In order to prevent accumulation of sewage during prolonged periods of low usage of the system, such as at night, an auxiliary aeration system is provided for introducing a volume of air independently of the air admitted through operation of the suction valves.
Claims11
In a vacuum drainage system comprising:
- a collecting tank, a sewage drain conduit in fluid communication with said collecting tank;
- means for inducing a vacuum in said collecting tank to effect a flow of sewage through said sewage drain conduit into said collecting tank;
- suction valve means for admitting a quantity of sewage into said sewage drain conduit;
- means for opening said suction valve means when a quantity of sewage has collected in front of said suction valve means to permit a volume of sewage to flow into said fluid drain conduit and for retaining said suction valve open for a length of time sufficient to permit a first volume of air, in the amount of two to fifteen times said volume of sewage, to flow into said fluid drain conduit to drive the sewage through said sewage drain conduit
- the improvement which comprises:
- means for sensing the pressure of sewage at at least one location in said drain conduit as a function of time and for admitting, by thrusts, a further volume of air which is a multiple of said first volume of air into said sewage drain conduit in dependence upon the pressure of sewage at said location in said conduit independently of the first volume of air admitted into said conduit through said suction valve when the pressure of sewage sensed exceeds a predetermined value for a predetermined time interval.
In a vacuum drainage system comprising:
- a collecting tank, a sewage drain conduit in fluid communication with said collecting tank;
- means for inducing a vacuum in said collecting tank to effect a flow of sewage through said sewage drain conduit into said collecting tank;
- suction valve means for admitting a quantity of sewage into said sewage drain conduit;
- means for opening said suction valve means when a quantity of sewage has collected in front of said suction valve means to permit a volume of sewage to flow into said fluid drain conduit and for retaining said suction valve open for a length of time sufficient to permit a first volume of air, in the amount of two to fifteen times said volume of sewage, to flow into said fluid drain conduit to drive the sewage through said sewage drain conduit;
- the improvement which comprises:
- means for sensing the amount of sewage at at least one location in said drain conduit as a function of time and for admitting, by thrusts, a further volume of air which is a multiple of said first volume of air into said sewage drain conduit in dependence upon the amount of sewage at said location in said conduit independently of the first volume of air admitted into said conduit through said suction valve when the amount of sewage sensed exceeds a predetermined value for a predetermined time interval.
Dependencies are inferred from the claim text.