GB2345138A

GB2345138A - Overflow detector particularly for toilet cistern

Info

Publication number: GB2345138A
Application number: GB9828361A
Authority: GB
Inventors: David Azouri
Original assignee: Individual
Current assignee: Individual
Priority date: 1998-12-22
Filing date: 1998-12-22
Publication date: 2000-06-28
Also published as: GB9828361D0

Abstract

An overflow detector for a liquid container 102, such as a toilet cistern, having an overflow outlet 105, comprising a detector 101 for generating an electric warning signal to activate an audible and/or visible alarm when the liquid in the container 102 is at or above a level 104 at which the liquid flows through the overflow outlet 105. The detector 101 may comprise a level sensor to detect the level of liquid within the container 102, or may comprise a flow sensor (250, figure 9) to detect the presence of flow in the overflow outlet 105. The level sensor preferably comprises an anode and a cathode that contact the liquid at or above the overflow level 104. A system is also provided in which overflow detectors are provided on several containers and a remote indicator indicates which of the detectors is sending a warning signal.

Description

AN OVERFLOW DETECTOR This invention relates to an overflow detector.

Water cisterns and other water tanks are provided with overflow pipes so that should a level controller, e. g a ball valve, controlling a flow of water into the cistern fail to operate properly the overflowing water is lead away through an overflow pipe to the outside of a building in which the cistern is located, or to some other form of drainage.

It is a requirement of such overflows, imposed by water regulations or other legislation, that such an overflow should be apparent, in order to conserve water, and to prevent an overflow situation continuing indefinitely. It is also a requirement where there is more than one cistern, that it should be possible to identify which cistern is overflowing. A visual indication of the overflow from a cistern 1 may be provided by, for example, the overflow pipe 2 opening directly onto a floor, or preferably, as shown in Fig. 1, leading outside the building through a wall 3, where the water flowing from the overflow pipe 2 can be seen. Alternatively, where, an overflow cannot conveniently be led outside a building and the overflow 4 flows, for example, into a flush-pipe 5 of a w. c. pan 6, it is necessary to provide a tundish 7, ie, an air gap is introduced between the overflow pipe 4 and a funnel arrangement, so that the flow of water is visible, as shown in Fig. 2. Where the cistern 1 is concealed behind panelling, a display window must be provided in the panelling so that the tundish is visible.

All these arrangements have disadvantages as indications that a cistern is overflowing. In the case of an overflow pipe leading directly onto the floor there is a danger of flooding if the overflow is not noticed. In the case of an overflow pipe leading outside the building, the overflowing water may not be immediately noticed, and even when noticed, it may not be easy to trace which cistern is overflowing. In the case of the tundish, apart from being unsightly, there is no guarantee that the overflow situation will be observed within a reasonable time, if at all, especially where the tundish is behind a display window.

The present invention seeks to mitigate these disadvantages.

According to one aspect of this invention, there is provided an overflow detector for a container having an overflow outlet, the overflow detector comprising a level detector adapted to generate an electrical warning signal to a warning device when a level of a liquid within the container is at or above a predetermined level at which the liquid flows out of the container through the overflow outlet.

Conveniently, the warning device is an audible warning device.

Conveniently or additionally the warning device is a visual warning device.

Advantageously the warning device is a remote warning device.

Preferably the remote warning device is connectable to a plurality of overflow detectors and includes indicating means for indicating which of the plurality of level detectors is sending a warning signal.

Conveniently the level detector comprises a cathode and anode disposed within the container such that when the level of the liquid is at or above a predetermined level, the liquid produces a change in an electrical parameter of an electrical circuit including the anode and cathode to generate the warning signal.

Advantageously the electrical parameter is resistance.

Alternatively the electrical parameter is capacitance.

Advantageously the level detector comprises a T-shaped body having a longitudinal portion and a transverse portion, the transverse portion containing the anode and the cathode on opposed arms of the transverse portion, electric conductors passing from the anode and cathode respectively along the respective arms of the transverse portion and through the longitudinal portion to electrical connectors disposed at the end of the longitudinal section remote from the transverse section, such that the longitudinal portion may be passed through a wall of the container with the transverse portion located within the container so that the liquid is in contact with the anode and cathode when the level of the liquid is at or above the predetermined level.

According to a second embodiment of the first aspect of the invention there is provided an overflow detector for a container having an overflow outlet, the overflow detector comprises a detector adapted to send an electrical warning signal to a warning device when a flow of liquid is detected in the overflow outlet.

According to a second aspect of the invention there is provided an overflow detector as described in combination with the container, in which the overflow outlet leads into an overflow pipe which is integral with the body of the container.

According to a third aspect of the invention there is provided a level detector for detecting a level of a liquid within a container, the level detector comprising a cathode and an anode adapted for location within the container such that when the level of the liquid is at or above the predetermined level, the liquid within the container produces a change in an electrical parameter of an electrical detection circuit including the anode and cathode to generate a warning signal.

Conveniently, the level detector is substantially T-shaped with a transverse section and a longitudinal section, wherein the cathode and anode are disposed in opposed arms of the transverse section and electrical connectors pass from the anode and cathode through the transverse and longitudinal section to electrical connectors at an end of the longitudinal section remote from the transverse section.

According to a fourth aspect of the invention, there is provided a cistern having an overflow outlet and an overflow detector for generating an electrical warning signal when the level of liquid in the cistern is sufficient for the liquid to flow through the overflow outlet.

Conveniently, the overflow outlet opens into an overflow channel integral with a wall and/or a floor of the cistern.

The present invention has the advantage of producing an audible and/or visible warning whenever an overflow occurs, which readiiy identifies which cistern is overflowing without the danger of flooding or the need to lead overflow pipes outside a building or to provide a tundish arrangement and where appropriate a tundish viewing window.

Because an overflow detector according to the invention provides warning of an overflowing container, the invention provides the advantage that an overflow outlet and pipe can be incorporated integrally into the container.

The invention will now be described by way for example, with reference to the accompanying drawings, in which: Figure 1 shows an overflow pipe passing to the outside of a building according to the prior art; Figure 2 shows an overflow via a tundish according to the prior art; Figure 3 shows an overflow detection system according to the present invention; Figure 4 shows the overflow detection system of Fig 3 connected to a warning device (not to scale); Figure 5 shows a plan view of a level detector for use in the embodiment shown in Figures 3 & 4; Figure 6 shows a side view of the level detector of Figure 5; Figure 7 shows the level detector of Fig 5 connected to the warning device of Fig. 4; Figure 8 shows a second embodiment of the invention; and Figure 9 shows a third embodiment of the invention.

In the figures, like reference numerals denote like parts.

A cistern 100, as shown in Fig. 3, is fitted with an overflow detector to detect a predetermined level 104 of liquid in the cistern 100, at which liquid in the cistern 100 flows through an overflow outlet 103, thence by means of an overflow pipe 105 to a flush-pipe 106. It will be understood that the overflow outlet need not necessarily be located in a side wall of the cistern, but could be located in any other wall or the overflow pipe could pass through an aperture in a floor of the cistern with an overflow outlet into the overflow pipe at the predetermined level.

The overflow detector has a level detector 101 located in a wall 102 of the cistem 100, the level detector 101 being level with the underside of the overflow outlet 103. The level detector 101 is electrically connected to a remote overflow warning device 400 as shown in Fig 4.

As shown in detail in Figs 5 & 6, the level detector 101 has a T-shape body having a transverse portion 201 and a longitudinal portion 202 both of an electrically insulating material. Disposed in respective opposed arms 203,204 of the transverse portion 201 in a surface 205 remote from the longitudinal portion 202 are located respectively an electrically conducting anode 206 and an electrically conducting cathode 207 embedded within the transverse arms 203,204 respectively so that surfaces of the anode 206 and cathode 207 respectively are exposed on the surface 205. The anode 206 and cathode 207 may conveniently be of metal. Electrical conductors 208,209 pass from the anode 206 and cathode 207 respectively along the transverse portion 201 toward the longitudinal portion 202 and through the longitudinal portion 202 to two separate electrical connectors 210, 211 respectively protruding from an end 212 of the longitudinal portion 202 remote from the transverse portion 201. The longitudinal portion 212, which is spherical in transverse cross-section, is provided with an external thread 213 to receive a wing nut 214, as shown in Fig 6.

In use, the longitudinal portion 202 of the detector 101 is passed through an aperture 215 in a wall 102 of the cistern 100, as shown in Fig. 4, at the predetermined level of liquid 104 at which the liquid begins to flow through the overflow outlet 103, with the cathode 207 and anode 206 arrange horizontally in the plane defined by the predetermined level 104 of liquid. When the level of liquid reaches the predetermined level 104, an electrical connection is established between the anode 206 and cathode 207 through the liquid, which may be detected by an external circuit in a remote warning device 400. It will be apparent to the person skilled in the art, that alternatively one of the cathode 207 and anode 206 may be located below the predetermined level 104. As an alternative to a resistive connection between the anode 206 and cathode 207, a change in capacitance may be detected by the external circuit. It will be understood that a single electrode may alternatively be used in the external circuit and the change in resistance or capacitance of that electrode to earth, for example, be detected.

It will be apparent to the person skilled in the art that alternatively, as shown in Fig. 9, the detector may be located in the overflow pipe 105 to detect the presence of liquid flowing through the overflow pipe. Similarly, any known flow detector 250, located, as appropriate, either internally or externally of the overflow pipe 105, could be used to detect a flow of liquid through the overflow pipe 105 and trigger the warning device 400.

The detector circuit may be battery-powered and be provided with a battery low warning system know per se, for example, similar to that used in smoke detectors. Alternatively, the detector circuit may be mains powered.

The warning device 400, as shown in Figs. 4 & 7, includes an audible warning device 401 and a plurality of warning indicator lights 402, each warning light 402 being connected to a remote level detector 101 in a respective cistern 100 to indicate which cistern 100 is overflowing. It will be apparent to the person sldlled in the art that other forms of indicator for example a liquid crystal display, could be used to indicate which connected cistern was overflowing.

In a second embodiment of the invention, as shown in Fig 8 because the overflow detector will warn of an overflow, the overflow outlet and pipe may be integral with the cistern without an overflowing liquid needing to be visible.

Therefore, both an overflow pipe 305 and a detector 306,307 are built integral with the cistern 300, that is, the overflow pipe 305 may be integral with a wall 302 and floor 301 of the cistern 300 and an anode 306 and cathode 307 may be embedded in the wall 302 of the cistern 300 at the predetermined level 304 of an overflow outlet 303. Alternatively, one of the anode 306 and cathode 307 may be located below the pre-determined level as shown, in the case of the anode 306, in Fig. 8.

Although the invention has been described in relation to a particular level detector, it will be apparent to the person skilled in the art that any known level detector may be used to detect when the level of liquid reaches a level at which liquid flows through an overflow aperture. Such level detectors may be, for example, reed switches, radio frequency sensing, proximity sensors, float switches, conducting or resistance content gauges.

It will be apparent to the person sldlled in the art that the invention has application to any liquid container provided with an overflow outlet.

Claims

CLAIMS: 1. An overflow detector for a container having an overflow outlet, the overflow detector comprising a level detector adapted to send an electrical warning signal to a warning device when a level of a liquid within the container is at or above a predetermined level at which the liquid flows out of the container through the overflow outlet.
2. An overflow detector as claimed in claim 1 wherein the warning device is an audible warning device.
3. An overflow detector as claimed in claims 1 or 2, wherein the warning device is a visual warning device.
4. An overflow detector as claimed in any of the preceding claims wherein the warning device is a remote warning device.
5. An overflow detector as claimed in the claim 4, wherein the remote warning device is connectable to a plurality of overflow detectors and includes indicating means for indicating which of the plurality of level detectors is sending a warning signal.
6. An overflow detector as claimed in any of the preceding claims, wherein the level detector comprises a cathode and anode disposed within the container such that when the level of the liquid is at or above a predetermined level, the liquid produces a change in an electrical parameter of an electrical circuit including the anode and cathode to generate the warning signal.
7. An overflow detector as claimed in claim 6, wherein the electrical parameter is resistance.
8. An overflow detector as claimed in claim 6, wherein the electrical parameter is capacitance.
9. An overflow detector as claimed in claim 6, wherein the level detector comprises a T-shaped body having a longitudinal portion and a transverse portion, the transverse portion containing the anode and the cathode on opposed arms of the transverse portion, electric conductors passing from the anode and cathode respectively along the respective arms of the transverse portion and through the longitudinal portion to electrical connectors disposed at the end of the longitudinal section remote from the transverse section, such that the longitudinal portion may be passed through a wall of the container with the transverse portion located within the container so that the liquid is in contact with the anode and cathode when the level of the liquid is at or above the predetermined level.
10. An overflow detector for a container having an overflow outlet, the overflow detector comprising a detector adapted to send an electrical warning signal to a warning device when a flow of liquid is detected in the overflow outlet.
11. An overflow detector as claimed in any of the previous claims in combination with the container, wherein the overflow outlet leads into an overflow pipe which is integral with the body of the container.
12. A level detector for detecting a level of a liquid within a container, the level detector comprising a cathode and an anode adapted for disposal within the container such that when the level of the liquid is at or above the predetermined level, the liquid within the container produces a change in an electrical parameter of an electrical circuit including the anode and cathode, to generate a warning signal.
13. A level detector as claimed in claim 12, wherein the level detector is substantially T-shaped with a transverse section and a longitudinal section, wherein the cathode and anode are disposed in opposed arms of the transverse section and electrical connectors pass from the anode and cathode through the transverse and longitudinal section to electrical connectors at an end of the longitudinal section remote from the transverse section.
14. A cistern having an overflow outlet and an overflow detector for generating an electrical warning signal when the level of liquid in the cistern is sufficient for the liquid to flow through the overflow outlet.
15. A cistern as claimed in claim 14, wherein the overflow outlet opens into an overflow channel integral with a wall and/or a floor of the cistern.
16. An overflow detector substantially as hereinbefore described with reference to, and as illustrated in Figs 3-7 or 8 of the accompanying drawings.
17. A level detector substantially as hereinbefore described with reference to, and as illustrated in Figs 3-7 or 8 of the accompanying drawings.
18. A cistern substantially as hereinbefore described with reference to, and as illustrated in Figs 3-7 or 8 of the accompanying drawings.