INSERT FOR ONE WAY FLOW OF LIQUID AND AIR FOR PREVENTION OF RETURN OF ODOUR AND WASTE WATER FOR SINKS IN SEWAGE

INSTALLATIONS Technical field The invention relates to the field of domestic plumbing installations, with waste water sinks, more precisely to the odour seals intended for prevention of return of odour and waste water from sewer pipes.

According to the International Patent Classification the present invention is denoted by the following classification symbols ⁽⁷⁾ E03C 1/28 and E03C 1/282. Background Art

A technical problem being solved by the present invention consists of the following: how to design an insert for one way flow of liquid and air which will enable undisturbed drainage of waste water from a bathroom and similar spaces through appropriate sinks in aim to prevent return of odour as well as entry of different kinds of vermin from sewer pipes, especially in cases of lack of water in sinks due to irregular use, or during summertime when water evaporates because of high temperatures. From the state of the art is generally known drainage of waste water from domestic plumbing installation by appropriate sinks and built-in U-shaped traps in aim to prevent return of odour as well as entry of different kinds of vermin from sewer pipes in residential and any other spaces that has proved to be insufficiently efficient in practice. These unwanted and unpleasant occurrences arise especially during summertime when level of water in sinks decreases due to evaporation caused by high temperatures, and also due to changes in atmospheric pressure and frequency of use of sanitary facilities. A similar solution to the defined technical problem has not been found by both a search carried out in the patent documentation and an inspection of the expert literature in the relevant technical field. Disclosure of Invention

An insert for one way flow of liquid and air is intended for prevention of return of odour and waste water from sinks in sewage installations as well as entry of different kinds of vermin in any kind of spaces. On the one hand, the design of the insert enables free flow of liquid and air from the sink to the drainage sewer pipe, and on the other hand, it disables return of liquid, polluted air and different kinds of vermin in the mentioned spaces, because a membrane closes passage leading in that direction.

In existing sewage installations there are two types of sinks: the one with vertical drainage of waste water and the one with horizontal drainage that caused need for designing two different constructions of the present insert that can be found in retail stores. For vertical sinks is intended an insert consisting of a plastic holder in a shape of segment of a circle, a resilient rubber membrane, a rubber washer and a plastic ring. All the mentioned elements are circular, except the holder. The rubber membrane is fixed by means of gluing in its upper part, and the rubber washer and the plastic ring are mutually glued over their entire contact surface. Compactness of the insert is achieved through connection of all four mentioned elements by means of two plastic wedges that are nailed in the holder and the other mentioned elements. Further, the insert is inserted in a short plastic pipe forming driving fit and such formed assembly is placed through a vertical opening of the sink. The design of the insert intended for horizontal sink is generally same as for the previous one, except that semicircular openings are made in the upper half of both the rubber washer and the plastic holder, so appropriate lower part replace division wall standing in the sink, which has to be removed by means of cutting to provide a space for positioning of the present insert.

Disregarding where the insert is going to be mounted, its mode of operation is the same. A tongue of the membrane moves freely from right to left, i.e. in the direction from the interior of the sink to the sewer pipe and it enables flow of liquid and air. In opposite direction, i.e. from left to right, the membrane can not pivot, because it leans on the rubber washer, which leans further on the plastic ring, both of them having smaller internal diameters than the membrane diameter, whereby preventing return of liquid and air in the interior of the sink. Brief Description of Drawings To clarify the invention, two exemplary embodiments of an insert according to the invention will hereinafter be described with reference to the accompanying drawings. In these drawings: Fig. 1 shows a plastic membrane holder; Fig. 2 shows a resilient rubber membrane; Fig. 3 shows a ring like rubber washer intended for vertical waste pipe; Fig. 4 shows a plastic ring intended for vertical waste pipe; Fig. 5 shows a perspective view of the insert and a way of it being placed in a sink having vertical waste pipe;

Fig. 6 shows a rubber washer with semicircular opening intended for horizontal waste pipe;

Fig. 7 shows a plastic holder with semicircular opening intended for horizontal waste pipe; and Fig. 8 shows a perspective view of the insert and a way of it being placed in a sink having horizontal waste pipe. Best Mode for Carrying Out the Invention

An insert for one way flow of liquids and air mounted in a waste pipe of a sink in a bathroom or any other space in a building enables normal draining of waste water in sewage installations and also prevents return of polluted air and different kinds of vermin in the bathroom and any other space where sinks exist. A need for mounting the insert in the sink exists even if a system with U-shaped trap operates in it enabling this function by means of providing a water barrier. The system with U-shaped trap does not always operate efficiently, on the one hand, due to poor manufacture, and on the other hand, due to lack of water in the U-shaped trap or due to irregular use (e.g. in weekend cottages), or during summertime when water evaporates because of high temperatures. Sometimes it may happen even due to considerable change in atmosphere pressure.

The present insert is intended to be placed in a vertical or horizontal waste pipe of the sink, depending of its position in existing sewage system in residential and other spaces.

An insert intended for being placed in the vertical waste pipe of the sink consists of a plastic holder 1 in a form of segment of a circle, a resilient rubber membrane 2, ring like rubber washer 3 and a plastic ring 4. The membrane 2, the washer 3 and the ring 4 are circular, and their outside diameters are equal, whereas in the washer 3 and ring 4 are made circular openings 7, 8, which are flattened in their upper parts. The ring 4 is thicker in aim to lean tighter when it is inserted in the waste pipe. The upper part of membrane 2 is fixed by means of glue, while the washer 3 and the ring 4 are mutually glued over their entire contact surface. Compactness of the insert is provided by fixing all four elements of the insert by means of two plastic wedges 11. The insert is inserted in a short plastic pipe 12 having fixedly attached rim 15 with driving fit, and then the complete assembly is inserted in vertical opening of the sink 13.

An insert which is intended to be placed in the horizontal waste pipe of the sink 14 is also a compact assembly fixed by means of plastic wedges 1 1, whereas the rubber washer 5 and the plastic holder 6 are having both semicircular openings 9, 10 in the

upper half, so the appropriate full part having height "h" replaces existing dividing wall of the existing sink bowls, wherein the dividing wall has to be removed by simple cutting.

Disregarding where the present insert is going to be mounted, its mode of operation is the same. Under the pressure of liquid and air the rubber membrane 2 moves freely from right to left, i.e. in the direction from the interior of sink 13, 14 to drainage sewer pipe and it enables flow of liquid and air. In opposite direction, i.e. from left to right, the membrane 2 can not pivot, because it leans on the rubber washer 3, which leans further on the plastic ring 4, that is on the rubber washer 5, which leans further on the plastic holder 6, wherein all of them having smaller internal diameters than the diameter of membrane 2, whereby preventing return of liquid and air and entry of different kinds of vermin in the interior of the sink 13, 14.

In state of rest when water does not flow out in the sewage system, the membrane 2 is slightly closed, and in case that there is not pressure in sewage system, it rests and polluted air does not flow in. When water is flushed in a WC bowl or water is drained from the bath anywhere in the building, then pressure is increasing in common vertical, causing pressurizing the membrane which sealingly closes a passage for polluted air preventing its entry in any space.

Both types of the inserts can be placed in such manner to operate independently or to cooperate with existing systems with U-shaped trap that provides its better certainty. Preparation of the sink for use of both systems is very simple. In the case of the vertical waste pipe, the insert is being placed in the waste pipe and existing plastic bell takes its place over it. In the case of the horizontal waste pipe, a plastic dividing part which provides minimum level of water for the U-shaped trap is being removed, and its role is taken over by full part, i.e. dividing part having height "h" of both the rubber washer 5 and the plastic holder 6 glued onto it.