WO2018140998A1

WO2018140998A1 - A valve arrangement and an odour extraction device

Info

Publication number: WO2018140998A1
Application number: PCT/AU2018/000006
Authority: WO
Inventors: Geoffrey Charles Quick
Original assignee: Individual
Current assignee: Individual
Priority date: 2017-02-01
Filing date: 2018-01-31
Publication date: 2018-08-09
Anticipated expiration: 2019-08-01
Also published as: AU2018216626A1

Abstract

A valve arrangement (10) for a suction means, the valve arrangement (10) including: a valve inlet (14); a valve outlet (16); a one-way valve between the inlet (14) and the outlet (16), the one way valve including a elastomeric valve member (22) and a valve seat (28), the valve member (22) being biased towards a closed position substantially blocking gas communication between the inlet (14) and the outlet (16) by sealing engagement of the valve member (22) with the valve seat (28), the valve member (22) adapted for disengagement from the valve seat (28) to allow gas to flow between the inlet (14) and the outlet (16) responsive to a predetermined minimum pressure differential being generated across the valve member (22) by energising of the suction means, wherein the valve member (22) includes a first valve seat engaging region (22a) and a second valve seat engaging region (22b), the first valve seat engaging region (22a) being more flexible than the second valve seat engaging region (22b).

Description

A VALVE ARRANGEMENT AND AN ODOUR EXTRACTION DEVICE

FIELD

[0001 ] The present invention relates to a valve arrangement for a suction means and an odour extraction device for a toilet.

[0002] The invention has been primarily developed for use in toilets in fixed homes and will be described hereinafter with reference to this application. However, the invention is not limited to this particular use and is also applicable for use with toilets in other environments such as: marine vessels; mobile homes; campervans; recreational vehicles; caravans; portable buildings and portable toilets.

[0003] The valve arrangement aspect of the invention also finds application in respiratory devices.

BACKGROUND

[0004] The Applicant's international PCT patent application No. PCT/AU2007/000003

(WO 2007/079524) discloses embodiments of an odour extraction device for gravity flushing and syphonic flushing toilet pans. The disclosed odour extraction devices include a one way valve to prevent unpleasant odours from flowing from the sewer back to the toilet pan. The disclosed odour extraction devices utilise a suction fan to draw gas from within the pan and expel it through a duct into the pan's flushing outlet pipe. The gas then flows through the pan's flushing outlet pipe into the sewer.

[0005] The valves used in devices of this type often include a relatively rigid rubber valve member which seals against a plastic valve seat. The valve members are often delivered with a protective sili cone film thereon, which improves the sealing of the rubber valve member against the plastic valve seat, particularly at lower pressures. A disadvantage of such val ve members is the flow of gases past the valve members can dry out the silicone film and lead to a loss of such sealing effectiveness between the valve member and the valve seat. Another disadvantage is the silicone film can produce superior sealing results during initial testing (e.g. for regulatory compliance) which may not be achievable during longer term use. [0006] Another disadvantage of known val ve members is that they only function correctl y within a relatively small pressure range. Valve members that are flexible enough to seal at lower pressures (e.g. 0-50 PA) can distort and lose sealing at higher pressures (e.g. 500 Pa), by "blowing out". Valve members that are rigid enough to maintain a seal at higher pressures will often distort enough to not reliably seal at lower pressures.

[0007] It is an object of the present invention to substantially overcome or at least ameliorate one or more of the above disadvantages.

SUMMARY OF THE INVENTION

[0008] Accordingly, in a first aspect, the present invention provides a valve arrangement for a suction means, the valve arrangement including:

a valve inlet;

a valve outlet;

a one-way valve between the inlet and the outlet, the one way valve including a elastomeric valve member and a valve seat, the valve member being biased towards a closed position substantially blocking gas communication between the inlet and the outlet by sealing engagement of the valve member with the valve seat, the valve member adapted for

disengagement from the valve seat to allow gas to flow between the inlet and the outlet responsive to a predetermined minimum pressure differential being generated across the valve member by energising of the suction means,

wherein the valve member includes a first valve seat engaging region and a second valve seat engaging region, the first valve seat engaging region being more flexible than the second valve seat engaging region.

[0009] The valve arrangement is preferably for a toilet odour extraction device.

[0010] In a second aspect, the present invention provides an odour extraction device for a toilet pan, the odour extraction device including:

a gas inlet adapted for gas communication with an interior of the toilet pan above a water level in the pan;

a gas outlet in gas communication with the inlet and adapted for gas communication with a sewer pipe;

a valve inlet in gas communication with the gas inlet; a valve outlet in gas communication with the gas outlet;

a suction means adapted to, upon energisation, propel gas from the gas inlet to the gas outlet;

a one-way valve between the inlet and the outlet, the one way valve including a elastomeric valve member and a valve seat, the valve member being biased towards a first closed position substantially blocking gas communication between the inlet and the outlet by sealing engagement of the valve member with the valve seat, the valve member adapted for disengagement from the valve seat to allow gas to flow between the inlet and the outlet responsive to a predetermined minimum pressure differential being generated across the valve member by energising of the suction means,

[001 1 ] The first valve seat engaging region preferably abuts the valve seat in the first closed position. The second valve seat engaging region is preferably proud of the valve seat in the first closed position. The second valve seat engaging region preferably abuts the valve seat in a second closed position, with the valve member being closer to the inlet in the second closed position compared to the first closed position. The valve member is preferably driven to the second closed position by back pressure from the outlet. The first valve seat engaging region preferably remains abutted against the valve seat in the second closed position.

[0012] The valve seat preferably includes first and second valve seat surfaces. The first valve seat engaging region engages the first valve seat surface in the first closed position. The second val ve seat engaging region is proud of the second val ve seat surface in the first closed position. The second valve seat engaging region engages the second valve seat surface in the second closed position.

[0013] The first valve seat engaging region and the second valve seat engaging region are preferably formed from the same material, with the first valve seat engaging region being thinner than the second valve seat engaging region. The first valve seat engaging part and the second valve seat engaging part are preferably integrally formed. [0014] The first valve seat surface is preferably smaller, and most preferably within, the second valve seat surface. The first and second valve seats are preferably generally round and concentrically arranged. The first and second valve seats are preferably located on distal edges of first and second upstanding cylindrical flanges. The first valve seat surface is preferably, in an axial direction, closer to the inlet than the second valve seat surface.

[0015] The first valve seat engaging region is preferably smaller than the second valve seat engaging region. The first and second valve seat engaging regions are preferably generally round and concentrically arranged. The first and second valve seat engaging regions are preferably outwardly extending annular flanges. The first valve seat engaging region is preferably, in a axial direction, closer to the inlet than the second valve seat engaging region.

[0016] The elastomeric valve member preferably includes a relatively rigid inner part with an axially extending guide cylinder. The guide cylinder preferably slidably engages with an axially extending guide post.

[0017] The valve member is preferably biased towards the first closed position by gravity. The valve member is preferably lower in the second closed position compared to the first closed position.

BRIEF DESCRIPTION OF THE DRAWINGS

[0018] A preferred embodiment of the present invention will now be described, by way of an example only, with reference to the accompanying drawings wherein:

[0019] Fig. 1 is a schematic cross sectional side view of an embodiment of an odour extraction device for a toilet with an embodiment of a valve arrangement for a suction means therein, the valve arrangement being shown in a first closed position by gravity;

[0020] F ig. 2 is a schematic cross sectional side view of the odour extraction device and the valve arrangement shown in Fig. 1 , the valve arrangement being shown in an open position;

[0021 ] Fig. 3 is a schematic cross sectional side view of the odour extraction device and the valve arrangement shown in Fig. 1 , the valve arrangement being shown in a second closed position by back pressure; and [0022] Fig. 4 is an enlarged partial detail view of the valve arrangement.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] Fig. 1 shows an odour extraction device 10 for use with a gravity flushing or siphonic flushing toilet pan. The odour extraction device 10 includes a plastic body 12 with a circular gas inlet 14 and a circular gas outlet 16. As is well understood by persons skilled in the art, the gas inlet 14 can recei ve unpleasant odours in gaseous form from an interior of the toilet pan and the gas outlet 16 can communicate those unpleasant odours to a sewer.

[0024] A suction fan 18 is positioned within the body 12. The fan is rotationally driven by an electric motor (not shown). A guide post 20 extends from the fan 18 and electric motor.

[0025] A rubber valve member 22 of generally annular construction is positioned within the body 12, generally adjacent the gas inlet 14. The valve member 22 is mounted to a rigid plastic inner part 24 from which extends a guide cylinder 26. The guide cylinder 26 slidably engages with the guide post 20 to guide the valve member 22 in axial movement towards and away from the gas inlet 14, as will be described in more detail below.

[0026] As best shown in Fig. 4, the valve member 22 includes a first valve seat engaging region, in the form of a first outwardly extending annular flange 22a, and a second valve seat engaging region, in the form of a second outwardly extending annular flange 22b. The flanges 22a and 22b are integrally moulded with the remainder of the valve member 22. As the first flange 22a is thinner, in an axial direction, than the second flange 22b it is more flexible than the second flange 22b. The outer diameter of the first flange 22a is also smaller than that of the second flange 22b. The body 12 includes a valve seat 28 adjacent to and around the gas inlet 14. The valve seat 28 includes a first valve seat surface, in the form of a distal edge 30a of a first upstanding cylindrical part 30, and a second valve seat surface, in the form of a distal edge 32a of a second upstanding cylindrical part 32. The outer diameter of the first cylindrical part 30 is smaller than that of the second cylindrical part 32 so as to position the first and second distal edges 30a and 32a adjacent to the first and second annular flanges 22a and 22b respectively.

[0027] The operation of the odour extracti on device 10 shall now be described. [0028] Fig. 1 shows the odour extraction device 10 when the motor that drives the fan 18 is not energised and the valve member 22 is in a first closed position, hereafter referred to as a "gravity closed" position. In the gravity closed position, the air pressure at the gas inlet 14 and the gas outlet 16 is substantially equal (i.e. atmospheric). The valve member 22 falls downwardly under the influence of gravity until the first annular flange 22a abuts the first distal edge 30a. Passage of gas into the air inlet 16 is then prevented by the sealing engagement of the first annular flange 22a with the first distal edge 30a. The second annular flange 22b sits slightly proud (i.e. above) and thus does not seal against, the second distal edge 32a in the gravity closed position. Importantly, as only the (more flexible) first flange 22a is sealingly engaged with the first valve seat surface 30a in this position, then correct sealing at relatively low pressures is reliably achieved.

[0029] Fig. 2 shows the odour extraction device 10 in an "open" position during energising of the motor to rotate the fan 18. The rotation of the fan 18 creates a suction/pressure differential of about 50 Pa across the gas inlet 14 which draws the val ve member 22 upwardly, against the influence of gravity. In the open position, neither the first or second annular flanges 22a or 22b of the valve member 22 engage with the respective first or second distal edges 30a or 32a of the valve seat 28. Accordingly, in the open position, gas is drawn into the body 12 through the inlet 14 and travels through the fan 18 and is then propelled out the body 10 through the outlet 16, as indicated by arrows 34.

[0030] Fig. 3 shows the odour extraction device 10 in a second closed position, hereafter referred to as a "back pressure closed" position. The motor driving the fan 18 is not energised in this position. The presence of back pressure at the gas outlet 18, as indicated by arrows 36, forces the valve member 22 further downwardly from the gravity closed position shown in Fig. 1 and closer to the valve seat 22 until the second annular flange 22b engages the second distal edge 32a. As the second valve seat flange 22b is thicker and less flexible than the first annular flange 22a, it is able to resist the back pressure at this position without significant distortion. This assists the sealing of the gas inlet 14 in two ways. Firstly, the valve member 22 is prevented from being forced to a position where the first flange 22a is inserted and/or driven through the gas inlet 14, thereby breaking or "blowing out" the seal. Secondly, the second flange 22b itself creates an additional gas tight seal against the second distal edge 30a. Such back pressure surges can be up to 500 Pa and can be caused by a pressure differential between atmosphere and the pan's flushing outlet pipe or the drainage system or the sewer mains becoming blocked.

[0031 ] The odour extraction device and valve arrangement described above are therefore advantageously able to establish and maintain sealing at both lower and higher pressures and thus function correctly over a much larger pressure range than known arrangements. Further, the relatively thin and more flexible first valve member flange functions reliably at lower pressures without requiring a protective silicone film.

[0032] Although the invention has been described with reference to a preferred embodiment, it will be appreciated by person skilled in the art that the invention may be embodied in many other forms.

Claims

CLAIMS:

1. A valve arrangement for a suction means, the valve arrangement including:

a valve inlet;

a valve outlet;

a one-way valve between the inlet and the outlet, the one way valve including a elastomeric valve member and a valve seat, the valve member being biased towards a closed position substantially blocking gas communication between the inlet and the outlet by sealing engagement of the valve member with the valve seat, the valve member adapted for disengagement from the valve seat to allow gas to flow between the inlet and the outlet responsive to a predetermined minimum pressure differential being generated across the valve member by energising of the suction means,

2. The valve arrangement of claim 1 , wherein in a first closed position, the first valve seat engaging region abuts the valve seat and the second valve seat engaging region is proud of the valve seat.

3. The valve arrangement of claim 2, wherein in a second closed position, the second valve seat engaging region abuts the valve seat, with the valve member being closer to the inlet in the second closed position compared to the first closed position.

4. The valve arrangement of claim 3, wherein the valve member is driven to the second closed position by back pressure from the outlet.

5. The valve arrangement of claim 3 or 4, wherein the first valve seat engaging region remains abutted against the valve seat in the second closed position.

6. The val ve arrangement of any one of the preceding claims, wherein the first val ve seat engaging region and the second valve seat engaging region are formed from the same material, with the first valve seat engaging region being thinner than the second valve seat engaging region.

7. The valve arrangement of any one of the preceding claims, wherein the first valve seat engaging region and the second valve seat engaging region are integrally formed with the valve member.

8. The valve arrangement of any one of the preceding claims, wherein the first valve seat engaging region is smaller than the second valve seat engaging region, the first and second valve seat engaging regions being generally round and concentrically arranged.

9. The valve arrangement of any one of the preceding claims, wherein the elastomeric valve member includes a substantially rigid inner part with an axially extending guide cylinder, the guide cylinder slidably engageable with an axially extending guide post.

10. The valve arrangement of any one of claims 2 to 9, wherein the valve member is biased towards the first closed position by gravity.

1 1. The valve arrangement of any one of claims 3 to 10, wherein the val ve member is lower in the second closed position compared to the first closed position.

12. An odour extraction device for a toilet pan, the odour extraction device including:

a val ve inlet in gas communication with the gas inlet;

a valve outlet in gas communication with the gas outlet;

a one-way valve between the inlet and the outlet, the one way valve including a elastomeric valve member and a valve seat, the valve member being biased towards a first closed position substantially blocking gas communication between the inlet and the outlet by sealing engagement of the valve member with the valve seat, the valve member adapted for disengagement from the valve seat to allow gas to flow between the inlet and the outlet responsive to a predetermined minimum pressure differential being generated across the valve member by energising of the suction means, wherein the valve member includes a first valve seat engaging region and a second valve seat engaging region, the first valve seat engaging region being more flexible than the second valve seat engaging region.

13. The odour extraction device of claim 12, wherein in a first closed position, the first valve seat engaging region abuts the val ve seat and the second val ve seat engaging region is proud of the valve seat.

14. The odour extraction device of claim 13, wherein in a second closed position, the second valve seat engaging region abuts the valve seat, with the valve member being closer to the inlet in the second closed position compared to the first closed position.

15. The odour extraction device of any one of claims 12 to 14, wherein the first valve seat engaging region and the second valve seat engaging region are formed from the same material, with the first valve seat engaging region being thinner than the second valve seat engaging region.

16. The odour extraction device of any one claims 12 to 15, wherein the first valve seat engaging region is smaller than the second valve seat engaging region, the first and second valve seat engaging regions being generally round and concentrically arranged.

17. The odour extraction device of any one of claims 12 to 16, wherein the valve member is lower in the second closed position compared to the first closed position.

18. The odour extraction device of any one of claims 14 to 17, wherein the first valve seat engaging region remains abutted against the valve seat in the second closed position.

19. The odour extraction device of any one of claims 14 tol 8, wherein in the first closed position the first valve seat engaging region engages a first valve seat surface and the second valve seat engaging region is proud of a second valve seat surface, and in the second closed position the second valve seat engaging region engages the second valve seat surface.

20. The odour extraction device of any one of claims, wherein the first and second valve seat engaging regions are outwardly extending annular flanges and the first valve seat engaging region is in an axial direction, closer to the inlet than the second valve seat engaging region.