GB2123454A - Drainage trap - Google Patents

Abstract

A trap comprises a funnel inlet portion (4) for catching, for example, the overflow from a hot-water tank, a water seal having the form of a U- shaped passageway (5-7-6), and an outlet (2) for connection to a sewer. In order to prevent drain gases escaping should the water-seal evaporate, a one-way valve (8) is provided upstream of the outlet wall (6) comprising a buoyant ball (10), a valve seat (9) and ball capture member (12). <IMAGE>

Description

SPECIFICATION Dropping funnels In accordance with the relevant regulations in some countries, it is necessary to provide in hotwater tanks an overpressure protection means from which, from time to time, in particular upon opening and closing the valves, water escapes in small quantities and is fed via a so-called dropping funnel into the mains sewer system. Dropping funnels of this type are designed as a trap (for example a U-bend) so as to obviate smells originating from the mains sewer system. Since water escapes relatively infrequently from the overpressure protection means, the sealing water in the trap soon evaporates, whereby the stench trap becomes ineffective.

The invention has the aim of eliminating this disadvantage, which is achieved in that in a dropping funnel, which is for connection to the mains sewer system, for the overflow from hotwater tanks and like overflows and which has a trap for preventing smells arising from the mains sewer system, a nonreturn valve is provided upstream of the overflow of the trap. A buoyant ball cooperating with a valve seat is particularly suitable as such a valve. If from time to time the sealing water in the trap evaporates, the buoyant ball rests on the valve seat and by closing the valve prevents the escape of gases from the mains sewer system.

One example of embodiment of the dropping funnel of the invention will be described in more detail below with reference to the drawings in which Figure 1 illustrates the dropping funnel diagrammatically in section and Figure 2 is a plan view.

In a housing 1, which has an outlet pipe 2 for the connection to the mains sewer system, there is provided an insert 3 which together with parts of the housing 1 forms a trap. The upper part of the insert 3 is widened to form a funnel 4 which is tightly connected with the housing and at the bottom opens into a vertical connecting pipe 5. In the vicinity of the connection of the outlet pipe 2 to the housing 1 there is provided an overflow 6 which ensures that sufficient sealing water remains in the trap. Accordingly, gases emanating from the mains sewer system are prevented by the sealing water in the trap from escaping via a funnel 4.

It is to be noted that water passing downwards from the funnel 4 through connecting pipe 5 flows via the bottom part 7 of the housing upwards towards the overflow edge 6. Along this path it passes a nonreturn valve 8 which, in the case illustrated, comprises a valve seat formed by a lip 9 and a buoyant ball 10. A vertical web 11 with a projection 1 2 prevents the ball 10 floating in the water seal from reaching the vicinity of the overflow 6.

If now the sealing water in the trap evaporates, the buoyant ball descends in accordancs with the falling water level on to the valve seat 8 and closes the valve while resting on the valve seat of preferably lip-shaped design, whereby the desired aim is achieved, namely of closing the trap upon drying out.

The invention may be used in other applications, especially where there is a likelihood of evaporation of the sealing water in a water seal trap.

1. A dropping funnel, for connection to the mains sewer system, for example for receiving an overflow from a hot-water tank or the like, and having a trap for preventing smells emanating from the mains sewer system, wherein upstream of the overflow of the trap there is provided a nonreturn valve, for example a buoyant ball arranged to cooperate with a valve seat, which valve is arranged to close when the sealing-water level in the trap drops.

2. A dropping funnel substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (2)

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Dropping funnels In accordance with the relevant regulations in some countries, it is necessary to provide in hotwater tanks an overpressure protection means from which, from time to time, in particular upon opening and closing the valves, water escapes in small quantities and is fed via a so-called dropping funnel into the mains sewer system. Dropping funnels of this type are designed as a trap (for example a U-bend) so as to obviate smells originating from the mains sewer system. Since water escapes relatively infrequently from the overpressure protection means, the sealing water in the trap soon evaporates, whereby the stench trap becomes ineffective. The invention has the aim of eliminating this disadvantage, which is achieved in that in a dropping funnel, which is for connection to the mains sewer system, for the overflow from hotwater tanks and like overflows and which has a trap for preventing smells arising from the mains sewer system, a nonreturn valve is provided upstream of the overflow of the trap. A buoyant ball cooperating with a valve seat is particularly suitable as such a valve. If from time to time the sealing water in the trap evaporates, the buoyant ball rests on the valve seat and by closing the valve prevents the escape of gases from the mains sewer system. One example of embodiment of the dropping funnel of the invention will be described in more detail below with reference to the drawings in which Figure 1 illustrates the dropping funnel diagrammatically in section and Figure 2 is a plan view. In a housing 1, which has an outlet pipe 2 for the connection to the mains sewer system, there is provided an insert 3 which together with parts of the housing 1 forms a trap. The upper part of the insert 3 is widened to form a funnel 4 which is tightly connected with the housing and at the bottom opens into a vertical connecting pipe 5. In the vicinity of the connection of the outlet pipe 2 to the housing 1 there is provided an overflow 6 which ensures that sufficient sealing water remains in the trap. Accordingly, gases emanating from the mains sewer system are prevented by the sealing water in the trap from escaping via a funnel 4. It is to be noted that water passing downwards from the funnel 4 through connecting pipe 5 flows via the bottom part 7 of the housing upwards towards the overflow edge 6. Along this path it passes a nonreturn valve 8 which, in the case illustrated, comprises a valve seat formed by a lip 9 and a buoyant ball 10. A vertical web 11 with a projection 1 2 prevents the ball 10 floating in the water seal from reaching the vicinity of the overflow 6. If now the sealing water in the trap evaporates, the buoyant ball descends in accordancs with the falling water level on to the valve seat 8 and closes the valve while resting on the valve seat of preferably lip-shaped design, whereby the desired aim is achieved, namely of closing the trap upon drying out. The invention may be used in other applications, especially where there is a likelihood of evaporation of the sealing water in a water seal trap. CLAIMS

1. A dropping funnel, for connection to the mains sewer system, for example for receiving an overflow from a hot-water tank or the like, and having a trap for preventing smells emanating from the mains sewer system, wherein upstream of the overflow of the trap there is provided a nonreturn valve, for example a buoyant ball arranged to cooperate with a valve seat, which valve is arranged to close when the sealing-water level in the trap drops.

2. A dropping funnel substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.