GB2306882A

GB2306882A - Thermostatic bath plug

Info

Publication number: GB2306882A
Application number: GB9522602A
Authority: GB
Inventors: Ben Thrift
Original assignee: Individual
Current assignee: Individual
Priority date: 1995-11-03
Filing date: 1995-11-03
Publication date: 1997-05-14
Also published as: GB9522602D0

Abstract

A bath plug comprises a base (10) for closing the drainage outlet of a bath, and a cover (14) which is normally engaged over the top of the base (10) to seal an outlet duct (12) through the latter. A mechanism (18, 24, 25) is contained within the base and cover and responds, when the temperature exceeds a threshold level, to lift the cover (14) out of engagement with the base (10) and thereby open the plug for water flow through the outlet duct. Optionally, an audible alarm (34) is arranged to emit sound when said operating mechanism operates.

Description

THERMOSTATIC BATH PLUG The present invention relates to a bath plug, and more particularly to a thermostatic bath plug which allows bath water to be discharged if its temperature exceeds a predetermined threshold.

When filling a bath, it is often difficult to continuously regulate the temperature of the bath water, particularly as either of the separate hot or cold water supplies may have variable temperature and/or pressure.

Consequently it is easily possible for the overall bath water temperature to become excessively high and therefore represent a danger, particularly to small children or the elderly.

A number of thermostatic water release systems have previously been disclosed which open to allow bath water to be released if its temperature becomes too high. However, these systems have typically been of a bulky construction. Further, they do not provide any indication of when they open.

I have now devised a bath plug which overcomes the above-mentioned problems.

In accordance with the present invention, there is provided a bath plug which comprises a base for closing the drainage outlet of a bath, the base having an outlet duct formed through its centre, a cover which is normally engaged over the top of the base to seal said outlet duct, and a mechanism contained within said base and cover which responds to temperature exceeding a threshold level to lift the cover out of engagement with the base.

Because the operating mechanism of the plug is contained within the base and cover, the plug presents a compact construction.

Preferably the base includes a tubular projection on its lower side, to locate within the drainage outlet of the bath. Preferably the operating mechanism is contained at least partially within this tubular projection: preferably the cover is domed and the remainder of the operating mechanism is enclosed by the cover.

Preferably the operating mechanism comprises a piston and cylinder mechanism, in which the cylinder is filled with a wax or other thermally metamorphic substance, which normally holds the piston within the cylinder: the mechanism further includes a spring which acts to extend the piston relative to the cylinder once a predetermined temperature is reached and the wax or other substance melts.

Preferably the plug includes an audible alarm which emits sound when the bath plug operates.

Thus, also in accordance with the present invention, there is provided a bath plug arranged to open in response to temperature above a predetermined threshold, and including an audible alarm.

Preferably the audible alarm comprises a mechanical arrangement which is driven by the flow of water which takes place when the plug opens. Preferably a cover, which lifts when the plug open, forms a bell housing of the mechanical alarm arrangement.

An embodiment of this invention will now be described by way of example only and with reference to the accompanying drawings, in which: FIGURE 1 is a perspective view of a thermostatic plug in accordance with this invention, shown in its normal or closed condition; FIGURE 2 is a cross-sectional view of the thermostatic bath plug of FIGURE 1: FIGURE 3 is a cross sectional view of the same plug, shown in its open condition; FIGURE 4 is a side elevation of the plug when closed; and FIGURE 5 is a top-plan view of the plug.

Referring to the drawings, there is shown a plug in accordance with the present invention, comprising a base 10 which has a flat, annular portion 32 from which a tapered, tubular portion 12 projects to locate in a standard drainage outlet, and a domed cover 14 having an apertured bracket 16 for attaching to a fixing point, typically by means of a length of chain.

As shown in Figure 2, the cover 14 is normally held with its peripheral rim in engagement with the top of the base 10, which is formed of rubber or other elastomeric material so that a watertight seal is formed. An operating mechanism for the plug is contained within the base and cover, and comprises a cylinder 24 to which the cover is mounted and a piston 25 which extends into the cylinder 24. The mechanism further comprises a coil spring 18 secured at one end around the cylinder 24 and is secured at its other end 22 to the bottom of a U-shaped member 21 fitted within the tubular portion 12 of the base. The spring 18 is normally held under compression, as shown in Figure 2.

When the water around the plug reaches a predetermined temperature, the wax within the cylinder 24 melts, releasing its grip on the piston 24. Accordingly, the spring 18 is able to expand and litt the cylinder 24 and thus lift the cover 14 from the base 10, as shown in Figure 3. Water is now able to flow through the plug, past the member 21, as indicated by the arrows 36.

As shown in Figure 2, a clapper mechanism 34 is mounted to the outside of the cylinder 24. When the cover is lifted to allow water to pass through the plug, the flow of the water excites the clapper mechanism 34 to spin and repeatedly strike the cover 14, acting as a bell housing, to give an audible alarm.

Claims

1) A bath plug which comprises a base for closing the drainage outlet of a bath, said base having an outlet duct formed through its centre, a cover which is normally engaged over the top of said base to seal said outlet duct, and a mechanism contained within said base and cover which responds to the temperature exceeding a threshold to lift said cover out of engagement with said base and thereby open the plug for water flow through said outlet duct.

2) A bath plug as claimed in claim 1, in which said base comprises a tubular projection on its lower side, to locate within said drainage outlet of the bath.

3) A bath plug as claimed in claim 2, in which said operating mechanism is contained at least partially within said tubular projection.

4) A bath plug as claimed in claim 3, in which said cover is domed and said operating mechanism is contained partially within said tubular projection and partially within said cover.

5) A bath plug as claimed in any preceding claim, in which said operating mechanism comprises a piston and cylinder mechanism, in which said cylinder is filled with a substance which normally holds said piston within said cylinder but which melts when the temperature exceeds said predetermined level, and a spring is provided to extend said piston when said substance melts.

6) A bath plug as claimed in any preceding claim, further comprising an audible alarm arranged to emit sound when said operating mechanism operates.

7) A bath plug as claimed in claim 6, in which said audible alarm comprises a mechanical arrangement which is driven by the flow of water which takes place when the plug is opened through said outlet duct.

8) A bath plug as claimed in claim 7, in which said cover forms a bell housing of said mechanical alarm arrangement.

9) A bath plug which is arranged to open in response to temperature exceeding a predetermined threshold level, and including an audible alarm.

10) A bath plug as claimed in claim 9, in which said audible alarm comprises a mechanical arrangement which is driven by the flow of water which takes place when the plug is opened in response to temperature exceeding said predetermined threshold level.

11) A bath plug as claimed in claim 10, further comprising a cover which lifts when the plug opens, and which forms a bell housing of said mechanical alarm arrangement.

12) A bath plug substantially as herein described with reference to the accompanying drawings.