WO1997009917A1

WO1997009917A1 - Self-emptying plug

Info

Publication number: WO1997009917A1
Application number: PCT/AU1996/000583
Authority: WO
Inventors: John Robert Liebert; Georg Yammouni; Lewis Alexander Meiller
Original assignee: SMARTPLUG Pty Ltd
Current assignee: SMARTPLUG Pty Ltd
Priority date: 1995-09-14
Filing date: 1996-09-16
Publication date: 1997-03-20
Anticipated expiration: 1998-03-14

Abstract

A self-emptying plug for a container of liquid which comprises: (a) a plug body (5) adapted to fit into a hole in a container, the plug body having a first outlet (16) for liquid therethrough and also being provided with valve guide means (13); (b) a cap means (1) adapted to fit over the plug body, the cap having a second outlet (10) for liquid therethrough; (c) valve means (3), having a head (11) and a stem (12), the stem being adapted to slide within the guide means and the head being adapted to bear against a valve seat means (2), as defined below; (d) spring means (4) adapted to force the valve head against the valve seat means, the spring means being further adapted to collapse at a selected hydrostatic pressure; and (e) valve seat means, as mentioned under (c) and (d), adapted to be located between the plug body and the cap means, whereby as hydrostatic pressure in the container increases to a selected pressure, the valve head is forced out of contact with the valve seat allowing liquid to flow through the first and second outlets out of the container.

Description

SELF-EMPTYING PLUG

FIELD OF THE INVENTION: This invention relates to a self-emptying plug for a container of liquid which plug is provided with a valve means which, when the hydrostatic pressure increases, depresses to allow emptying of the container when the pressure reaches a certain value.

BACKGROUND OF THE INVENTION: In this specification the word "container" is to be construed widely as meaning any vessel which can contain liquid and includes in particular bathtubs, spa baths, washing basins, laundry wash troughs and kitchen sinks.

There is a continuing problem concerning- overfilling of containers such as baths. This can cause particular problems where there is no arrangement to allow the removal of overflow water, for example, by means of a drain plug hole partly up the side of the container.

The self-emptying plug according to the invention provides at least a partial solution to this problem in that it allows drainage of liquid once a given pressure is exceeded.

BRIEF SUMMARY OF THE INVENTION: This invention provides a self-emptying plug for a container of liquid which comprises:

(a) a plug body adapted to fit into a hole in a container, the plug body having a first outlet for liquid therethrough and also being provided with valve guide means;

(b) a cap means adapted to fit over the plug body, the cap having a second outlet for liquid therethrough;

(c) valve means, having a head and a stem, the stem being adapted to slide within the guide means and the head being adapted to bear against a valve seat means, as defined below;

(d) spring means adapted to force the valve head against the valve seat means, the spring means being further adapted to collapse at a selected hydrostatic pressure; and

(e) valve seat means, as mentioned under (c) and (d), adapted to be located between the plug body and the cap means, whereby as hydrostatic pressure in the container increases to a selected pressure, the valve head is forced out of contact with the valve seat allowing liquid to flow through the first and second outlets out of the container. BRIEF DESCRIPTION OF THE DRAWINGS: The accompanying drawings illustrate three embodiments of the invention in which:

Fig I is an exploded view (as viewed down the page) of a first embodiment of a self -emptying plug;

Fig 2 is a cross-sectional view of the assembled plus of Fig 1 in its "closed" configuration;

Fig 3 is a cross-sectional view of the plug of Figs I and 2 in its "half-open" configuration,

and

Fig 4 is a cross- sectional view of the plug of Figs I to 3 in its "open" configuration.

Figure 5 is an exploded view (as viewed down the page) of a second embodiment of a self -emptying plug;

Figure 6 is a cross-sectional view of the assembled plug of Figure 5 in its "closed" configuration;

Figure 7 is a cross-sectional view of the plug of Figures 5 and 6 in its "half-open" configuration;

Figure 8 is a cross-sectional view of the plug of Figures 5 to 7 in its "open configuration; and

Figure 9 is a cross-sectional view of a "waste" plug according to the invention; and

Figure 10 is a cross-sectional view of a disassembled "waste" plug according to

Figure 9.

DETAILED DESCRIPTION OF THE INVENTION: It is preferred that the plug body be adapted to fit into a plug seat which is itself adapted to fit into a hole in the container The plug seat may be let into the container either from its outside or its inside. The plug body and the plug seat are both preferably substantially round in shape. The plug body is preferably supplied with a grid through which liquid may flow, that is, the first outlet may comprise a number of holes. For example, the grid may be star-shaped having partitions extending from a central structure. The valvue guide means is preferably located in the central structure. The valve guide means is preferably in a hole extending through the central structure referred to above.

The plug cap may be of any suitable shape but is preferably provided with a lip which fits down around the plug body The second outlet may take the form of a number of holes of any suitable shape let through the top of the cap, the only requirement being that the holes allow a sufficient volume of liquid to flow therethrough.

The spring means may be of any suitable type, for example, a helical or a spiral spring specially adapted to collapse at a selected hydrostatic pressure. However, another option is a specially adapted flat plate spring. A preferred option is a Belville spring which, in a first operative position, is conically shaped (in cross-section) outwards but can take up a flattened shape (also in cross-section), in a second operative position.

The valve seat means is prererably adapted to flex downwardly and follow the direction of travel downwards of the valve head. For example, it may be constructed as a flexible, flat ring which can fit over the top of the plug body, be held within the upper region of the plug cap. or be retained between the plug cap and the plug body

In a preferred embodiment, me self -emptying plug according to the invention may be provided with an override means which may be adapted to prevent opening of the valve means and/or close the valve means once open. For example, the plug body may be provided with a set of internal ramps arranged around the inside surface of the plug body These ramps are adapted to interact with a set of runner means attached to or forming pan of the valve means, whereby rotation of the valve means causes the runners to travel up the ramps forcing the valve means against the valve seat.

Alternatively, the cap may be provided with a pivoting hook or fork means which interacts with the upper end (as viewed in use) of the valve stem which may itself be suitably shaped to receive the pivoting hook or fork means. This example is suitable for prevention of opening of the valve means.

In another example, the override means incorporates a movable wedge means which may be shifted into and out of an operative position, forcing the valve head towards the valve seat or allowing it to move away from the valve seat.

In the second and third examples, the override means is operable from outside the plug cap and is preferably attached to or integral with the plug cap.

Turning to the accompanying drawings, in particular Fig 1: • numeral I indicates a plug cap: • numeral 2 indicates a valve seat; • numeral 3 indicates a valve; • numeral 4 indicates a Belville spring (in the flattened position); • numeral 5 indicates a plug body; and • numeral 6 indicates a plug seat.

Referring to plug cap 1. a pattern of outlets 10 is illustrated. Valve 3 is shown as having a valve head 11 and valve stem 12. Plug body 5 is shown with a centrally located valve guide 13 in a central structure 14 in a star-shaped grating 15 through which pass a number of outlets 16. Plug body 5 comprises a narrow diameter, lower portion 17 joined to a wider diameter upper portion 18. A series of outer barbs 19 are shown on the outer surface of upper portion 18. Finally, the plug seat 6 is provided with a base portion 20 and upstanding portion 21 which is adapted to fit snugly around plug body 5 using barbs 19 to improve fit.

Turning to Figures 2 to 4. the diagrams themselves and the associated text indicates how, in a first operative position (Fig 2), Belville spring 4 bears upwardly against valve head 11 which in turn bears circumferentially against valve seat 2. Belville spring 4 in this position clearly has a conical cross-section. As hydrostatic pressure increases, valve 3 is forced downwardly and valve seat 2 flexes downwardly to follow valve head 11. Finally, as can be seen from Fig 4, Belville spring 4 collapses to allow valve head 1 1 to leave contact with valve seat 2 and allow liquid to flow through the respective outlets 10 and 16.

Note that in another embodiment barbs 19 may be left out and the desired snug fit between plug body 5 and plug seat 6 achieved by appropriate shaping of these components.

Referring to Figures 5 to 8: - numeral 30 indicates a plug cap; - numeral 31 indicates a valve seat; - numeral 32 indicates an anti-flutter ring; - numeral 33 indicates a valve: - numeral 34 indicates a Belville spring (in the flattened position); - numeral 35 indicates a plug body; and - numeral 36 indicates a plug seat.

Referring to plug cap 30, a pattern of outlets 41 is illustrated. An eyelet 42 is formed on die top of plug cap 30 for use in attaching a chain.

Valve 33 is illustrated with a circular valve head 43 and a dependent valve stem 44. A twist bar 45 is formed on the top (as viewed in use) of valve head 33. A set of outwardly projecting runners 46 is provided in the bottom (as viewed in use) of valve head 33.

Plug body 35 is shown with a centrally located valve guide 47 in a central structure 48 in a star shape grating 49 through which pass a number of outlets 50. Plug body 35 comprises a narrow diameter, lower portion 51 joined to a wider diameter upper portion 52. A series of stops 53 and ramps 54 are shown as formed on the inner surface of upper portion 52. Again, upper and lower outwardly projecting rings 55 are formed on the outer surface of upper portion 52. These rings are useful to fit plug body 35 into plug seat 36 and cap 30.

Plug seat 36 is provided with a base portion 56 and upstanding portion 57 which is adapted to fit snugly around plug body 35.

The purpose of stops 53 and ramps 54 is to force runners 46 on valve 33 to travel upwards and fit against the lower side of valve seat 31 closing the outlet. when twist bar 45 is rotated.

Referring to Figures 6 to 8, the valve operates as follows;

Figure 6 shows the valve as closed;

Figure 7 shows the valve as it begins to open, the seat moves under water pressure to retain the seal:

Figure 8 shows the seal breaks about 2.5mm through the stroke, the valve opens fully and water passes; and

The fourth position (not shown) occurs when water head is reduced sufficiently and the valve closes.

Claims

The Claims Defining the Invention are as Follows:

1. A self -emptying plug for a container of liquid which comprises:

(b) a cap means adapted to fit over the plug body, the cap having a second outlet for liquid therethrough:

(e) valve seat means, as mentioned under (c) and (d), adapted to be located between the plug body and the cap means, whereby as hydrostatic pressure in the container increases to a selected pressure, the valve head is forced out of contact with the valve seat allowing liquid to flow through the first and second outlets out of the container.

2. A plug as claimed in claim 1, wherein the plug body is adapted to fit into a plug seat which is itself adapted to fit into a hole in the container.

3. A plug as claimed in claim 2, wherein the plug seat may be let into the container either from its outside or its inside.

4. A plug as claimed in any one of claims 1 to 3, wherein the plug body and the plug seat are both preferably substantially round in shape.

5. A plug as claimed in any one of claims 1 to 4, wherein the plug body is supplied with a grid through which liquid may flow, that is, the first outlet may comprise a number of holes.

6. A plug as claimed in any one of claims 1 to 5, wherein the valve guide means is located in the central structure.

7 A plug as claimed in any one of claims 1 to 6, wherein the valve guide means is a hole extending through the central structure referred to above.

8. A plug as claimed in any one of claims 1 to 7, wherein the plug cap is provided with a lip which fits down around the plug body.

9 A plug as claimed in any one of claims 1 to 7. wherein the second outlet takes the form of a number of holes of any suitable shape let through the top of the cap. the only requirement being that the holes allow a sufficient volume of liquid to flow therethrough.

10 A plug as claimed in any one of claims 1 to 7, wherein the spring means comprises a helical or a spiral spring specially adapted to collapse at a selected hydrostatic pressure.

1 1 A plug as claimed in any one-of claims 1 to 7. wherein the spring means is a specially adapted flat plate spring.

12. A plug as claimed in any one of claims 1 to 7, wherein the spring means is a Belville spring which, in a first operative position, is conically shaped (in cross-section) outwards but can take up a flattened shape (also in cross-section). in a second operative position.

13 A plug as claimed in any one of claims 1 to 12, wherein the valve seat means is preferably adapted to flex downwardly and follow the direction of travel downwards of the valve head.

14. A plug as claimed in any one of claims 1 to 13, wherein the self -emptying plug according to the invention may be provided with an override means which may be adapted to prevent opening of the valve means and/or close the valve means once open.

15 A plug as claimed in claim 14, wherein the plug body is provided with a set of internal ramps arranged around the inside surface of the plug body, these ramps being adapted to interact with a set of runner means attached to or forming pan of the valve means, whereby rotation of the valve means causes the runners to travel up the ramps forcing the valve means against the valve seat.

16. A plug as claimed in claim 14, wherein the cap is provided with a pivoting hook or fork means which interacts with the upper end (as viewed in use) of the valve stem which is itself suitably shaped to receive the pivoting hook or fork means.

17. A plug as claimed in claim 14, w, herein the override means incorporates a movable wedge means which may be shifted into and out of an operative position, forcing die valve head towards the valve seat or allowing it to move away from the valve seat.