GB2228620A - Liquid level warning devices - Google Patents

Abstract

A liquid level warning device comprises a body (1), a blind bore (6) in the body which in use is generally downwardly directed and a float (2) slidable in the blind bore; wherein the float comprises a magnetic or magnetizable material (3) and the body (1) comprises a switch element (8) responsive to the proximity of the magnetic material so as to actuate a warning means (10). The device may be used to give a warning of overfilling of a bath tub in a hotel. <IMAGE>

Description

LIQUID LEVEL WARMIflG DEVICE The present invention relates to a liquid level warning device particularly, although not exclusively, for preventing domestic bath tubs from overfilling.

It is a continuing problem, particularly in the hotel trade, where a number of bathrooms are positioned one over the other in a generally vertical array, as guests tend to leave baths running while attending to other matters. Although these baths are provided with an overflow pipe, these are usually insufficient to prevent the baths from overfilling if the taps are fully open. Accordingly floods in the bathroom and subsequent collateral damage to the rooms beneath are an ongoing problem.

Accordingly the need exists to provide a cheap self-contained unit which is capable of giving a warning of overfilling, preferably an audible warning.

Such a device must, of necessity, be reliable, cheap, and provided with an automatic re-set facility.

Accordingly the present invention provides a liquid level warning device comprising: a body, a blind bore in said body adapted in use to be generally downwardly directed ,and a float slidable in said blind bore, characterised in that the float comprises a magnetic or magnetizable material and in that the body comprises a switch element responsive to the proximity of said material, said switch element actuating a warning means.

The warning means is preferably a loud-speaker actuated by a battery.

In use, the device in accordance with the present invention is located at a suitable level within a bath tub; the float rising with the rising water level to actuate the switch means to give the warning.

In a preferred form of the invention the float is captive in the blind bore by means, for example, of an interned flange or rib at or about the entrance to the blind bore. This flange or rib may be configured to the lower portions of the float so that in the 'at rest' position thereof the float seals the blind bore against the ingress of vapour etc. A blind bore may be provided, at its uppermost portion, with an air vent. As will be appreciated, when the device has been operated a first time and the float has returned to its sealed position, a certain amount of moisture will remain the blind bore. Since the operating environment tends to be maintained at a temperature of about 200 - 21 C the air vent allows the blind bore to be evacuated of liquid by evaporation.When this step has been effected the float is then free to move unimpeded by liquid trapped above the seal.

In a preferred form of the invention the float and the body are formed generally of plastics material; the plastics material of the float encompassing preferably a magnet, disposed in a vertical or transverse orientation.

The blind bore may be generally cylindrical, in which case it is in practice necessary to dispose the magnetic or magnetizable material axially in an upwardly directed position.

However, in a preferred form of the invention the float is provided with an angular configuration such that it will only cooperate in the blind bore in a predetermined inter-relation. This enables the magnetizable material to be positioned at any predetermined point relative to the switch element.

In a preferred form of the invention, the body is formed of a plastics material which encompasses one or more laterally disposed switch elements which may, for example, be reed switches. Such reed switches may be in a spaced parallel relation in a vertical direction and the magnetizable material may be positioned adjacent a vertical side of the float. Accordingly, with the float rising in the blind bore the first, and then the second, reed switches will be operated. The reed switches can be separately connected such that a first audible signal can be output, followed by a second louder or differently pitched audible signal if the bath continues to fill.

In a preferred form of the invention the float has a rectangular cross-section.

It will be appreciated that the arrangement of the present invention is simple to produce and because the operative parts can be encapsulated in a water-proof material, are not prone to corrosion or electric degradation.

It is preferred that the units in accord with the invention also include a well-sealed battery and speaker unit integral with the said body. Alternatively, in a less preferred embodiment of the invention, the battery and speaker unit can be separately positioned and wired to the unit in accordance with the device of the present invention. This may be necessary where a powerful battery, or possibly a transformer, are required. It will be appreciated that in its preferred form a battery of comparatively low power can be utilised since the length of time over which the battery will actually operate is comparatively short. The units in accordance with the present invention may be conveniently provided with suction pads, or other means of fixing the unit to the side of a bath tub.

The invention will now be described, by way of illustration only, with reference to the accompanying drawings wherein: Figures 1 and 2 show a vertical cross-section through devices in accordance with the present invention in part diagrammatic form.

With reference particularly to Figure 1 a generally rectangular body 1 is formed of a plastics material and is provided in its intended lowermost face with an upperwardly directed blind bore 6. The blind bore 6 is provided with a lateral vent 7 which is optionally provided in the body 1. The blind bore 6 is provided at its lowermost edge with a sealing annulus 5 in the form of an inturned rib. The blind bore accommodates a generally rectangular float 2 provided, on its lowermost edge, with a sealing rim 4 for sealing co-operation with the rib 5.

The float 2 also comprises a magnet 3 generally centrally disposed in the upper face of the float.

Postioned superior to the blind bore 6 is a generally horizontally disposed reed switch 8, connected via a battery 9 to a speaker 10.

In use a rising water level acts upon the body 1 and the float 2. The body 1 being physically restrained relative to the liquid level, remains stationary, while the float 2 rises relative thereto. At a certain point the reed switch 8 comes within the magnetic field of the magnet 3 which actuates the switch 8, and hence the speakerlO. The switch will remain in its switched on condition until the water level, and hence the float 2, falls.

With reference to Figure 2 there is shown an alternative embodiment in accordance with the present invention. The parts similar to Figure 1 will not be described again and are similarly numbered.

In Figure 2 the float 2 is provided with laterally disposed magnets 3 arranged in a vertically stacked array within the body of the float 2.

The body 1 is also provided against one side of the blind bore 6, with two vertically spaced reed switches 8 and 8A. It will be seen that in the 'at rest' condition shown in Figure 2, the two reed switches 8 and 8A are positioned superior to the magnets 3.

However, as the water level rises, first the upper magnet 3 comes into proximity with the switch 8 and subsequently both switches 8 and 8A are positioned adjacent the upper and lower magnets 3. This enables a first signal to be output when the uppermost magnet 3 is juxtaposed the lowermost reed switch 8, while a second signal may be output when both the magnets are adjacent both the reed switches.

This enables a first audible signal to be output, followed by a second more urgent signal if the water continues to rise.

The invention provides, therefore, a device as just described, which is cheap, reliable and easy to install and maintain.

Claims (6)

CLAIMS.

1. A liquid level warning device complising: a body, a blind bore in said body adapted in use to be generally downwardly directed, a float slidable in said blind bore; characterised in that the float comprises a magnetic or magnetizable material and in that the body comprises a switch element responsive to the proximity of said material, said switch element being adapted to actuate a warning means.

2. A device according to Claim 1 characterised in that the float is captive in the blind bore by means of an inturned rib whereby the float is captive and seals the blind bore against moisture ingress in the at-rest position.

3. A device according to either of the foregoing claims characterised in that the blind bore is provided with an air vent communicating with the exterior.

4. A device according to any preceding claim characterised in that the float is provided with an angular configuration to maintain its un rotated locational position in the blind bore.

5. A device according to any preceding claim characterised in that the switch elements are to reed switches deposed in spaced parallel relation in the vertical sense, whereby when float rises the switches are actuated sequentially.

6. A liquid level warning device substantially as hereinbefore set forth with reference to, and/or as illustrated in, the accompanying drawings.