AU741190B2 - Foot valve - Google Patents

Description

I t Regulation 3.2 -1-

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION STANDARD PATENT

APPLICANT:

NUMBER:

FILING DATE: MILNES PTY. LIMITED PO 5482/97 7/ 3/1997

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Invention Title: FOOT VALVE The following statement is a full description of this invention, including the best method of performing it known to me/us: FOOT VALVE BACKGROUND TO THE INVENTION This invention relates to a foot valve of a non corrosive durable material which exhibits improved sealing and is suitable for use with any pump type.

Foot valves for use in irrigation are placed in the river or other water source from which water is required to be pumped. The standard such valve has previously been a metal valve which was bolted to a hose line through which the irrigation water was pumped.

Such valves have been prone to corrosion as well as problems relating to debris in the water becoming trapped in the actual valve mechanism. This prevents proper sealing which is required at even low heads of water in order to avoid the necessity of repriming of the pump after a period of non-use.

In order to minimise the corrosion problem it is desirable to use a synthetic material for the body of the valve in conjunction WP51\SPEC\MILN.CAP\BV\17 April, 1998

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3 with a metal valve mechanism. Such devices have however previously been impractical as the bolting of the foot valve to whatever hose is used has caused minor distortion in the valve body which has been sufficient to prevent an adequate sealing of the inner flap valve occurring.

Fully metal foot valves do not suffer this distortion problem but do suffer from corrosion.

In addition the standard hinged, single circular flap valve which has been used can easily be jammed open by entrapped debris.

SUMMARY OF THE INVENTION It is an object of this invention to provide a foot valve which is largely composed of a non corrosive material with an improved valve mechanism which will minimise the eeoc possibility of debris being caught in it.

The invention is a foot valve which includes a housing of a synthetic material having a first portion adapted to engage with a substantially metal valve member, which valve member includes at least one flap valve member located internally to the valve member, and a second portion through which fluid may enter and pass through to the valve member, the valve member being provided with flexible sealing means between itself and the first portion of the housing such that minor distortion of the housing does not lead to fluid leakage.

The foot valve of the invention has a polyethylene body, or valve housing, with a strainer device forming part of the inlet to it. Internal to this valve housing is a bronze, bi-valve, butterfly type flap valve which has two semi-circular flaps hinged across the diameter of the valve housing.

The precise materials used for the foot valve components are not germane to the Sooo: invention except that it is preferred that the valve housing be constructed of some strong synthetic material and the actual flap valve members of some strong heavy material such as bronze.

In order that the invention may be more readily understood a preferred embodiment of S the invention will be described in terms of the following drawings.

Fig. 1 Shows a schematic diagram displaying the function of the assembled foot valve; Fig.2 shows a front (upper) view of the flap valve component and its housing; Fig.3 shows a rear (inside) view of the flap valve component and its housing; Fig.4 shows a perspective view of the foot valve displaying the inlet to the valve mechanism; Although the foot valve described has of necessity no particular orientation it will be discussed herein using terms such as upper and lower as representing the orientation shown in the accompanying drawings.

In this embodiment of the invention the actual valve component of the foot valve (100) includes a cylindrical member (11) as shown in Fig.3, a first (the upper) portion (12) of which has a greater diameter than a second (the lower) portion (14) thereof. This permits an O ring (15) to be placed around the i outside of the cylindrical member immediately adjacent the lower edge of the upper portion (12).

In the interior of this valve component (10) the upper portion (12) has a greater internal and external diameter than the lower portion (14) thereof such that a lip (16) (Fig.1) is provided which acts as a valve seat for the edges of two semi-circular flap valve members (17) which hinge about a rod (18) connected WP51\SPEC\MILN.CAP\BV\17 April, 1998 6 across the internal diameter of the upper portion (12) of the valve component The arrangement is such that water pressure on the underside of these flap valve members will cause them to open upwards as shown in Fig.l. When the water pressure is removed the valve members will drop back onto the valve seat causing the valve to seal.

oo It would be possible to provide a sealing ring around the valve seat however in this preferred embodiment of the invention the lower side of the flap valve members are provided with a layer of rubber (19) which effects the seal. Apart from the O ring which is of rubber the components of this valve mechanism are S. constructed of bronze.

The housing (20) in which this valve mechanism is located is constructed from polyethylene and comprises a first (upper) annular section the top (21) of which has the widest diameter and is adapted to permit bolts to pass through holes (22) (Fig.3) to connect to a hose mounting or other device.

Below this upper portion the external diameter of the annular member decreases to that of a second (lower) portion (23) thereof WP51\SPEC\MILN.CAP\BV\17 April, 1998 7 and to connect with a moulded tubular strainer member (30) which allows water or other fluid through a hole (31) in the base thereof and through a series of horizontal slits in the sides of the strainer member.

The precise shape of the inlet holes in the strainer member or the type of strainer used are not particular to the invention and any shape which minimised the entry of debris while not .ooo significantly impeding the inflow of water would be appropriate.

In this embodiment of the invention the height of the strainer member is approximately twice that of the upper annular member.

The interior surface of the annular member has a stepped portion(26) such that the internal diameter of the upper portion is close to that of the upper portion (12) of the valve device and the diameter of the lower portion is approximately that of the lower portion (14) of the valve device.

The size of each is such that the valve device can be tightly located within the annular member with the O ring (15) providing a seal adjacent the upper edge (26) of the internal step in the annular member. The advantage of this arrangement is that any deformation of the housing (20) caused perhaps by bolting the WP51\SPEC\MILN.CAP\BV\17 April, 1998 8 topmost component (21) to a hose or such device will not break the seal provided by the 0 ring.

By this method the metal valve device is securely located within the light weight polyethylene housing and any minor distortion in the upper edge of the housing is accommodated by the 0 ring and cannot affect the sealing of the bi-valve members which are internal to member The invention would be equally applicable where the valve member contained a single flap valve however the embodiment of the invention described has the advantage that entrained debris in the fluid being pumped is less likely to cause the flap valves to be jammed open than debris collecting about a single hinge.

Whilst we have described herein one specific embodiment of the invention it is to be understood that variations and modifications in this can be made without departing from the spirit and scope thereof and it is envisaged that other embodiments of the invention will exhibit any number of and any combination of the features previously described.

WP51\SPEC\MILN.CAP\BV\17 April, 1998

Claims (9)

1. A foot valve which includes a substantially metal valve member and a housing of a synthetic material having a first portion adapted to engage with said valve member, which valve member includes at least one flap valve member located internally to the valve member, said housing having a second portion through which fluid may enter and pass through to the valve member, the valve member being provided with flexible sealing means between itself and the first portion of the housing such that minor distortion of the housing does not lead to fluid S. leakage.

2. A foot valve as claimed in claim 1 in which the sealing means is an O ring.

3. A foot valve as claimed in claim 1 in which the valve member includes a first portion of a greater internal and external diameter than a second portion thereof thus providing a step or lip between these portions and having on its exterior surface an O ring which is located immediately adjacent the lower edge of the first portion of the valve member providing a seal between the valve member and the interior of the first portion of the foot valve housing such that deformation of said first portion of the foot valve housing does not break the seal.

4. A foot valve as claimed in claim 3 in which the interior of said step or lip can act as a valve seat for the edges of one or more flap valve members.

P WP4 C\MILN.CAP\BV\5 October, 2001 o A flap valve as claimed in claim 4 in which two flap valve members hinge about a rod connected across the internal diameter of said first portion of the valve member.

6. A foot valve as claimed in claim 5 in which the flap valve members are each semi-circular in shape.

7. A foot valve as claimed in claim 1 in which the second portion of the foot valve is essentially tubular in shape with excised portions such that an effective filter is provided.

8. A foot valve substantially as hereinbefore described with reference to the accompanying drawings.

9 9 C C. C. 9 C C C 99** DATED THIS 17th DAY OF APRIL 1998 MILNES PTY. LIMITED By its Patent Attorneys A. TATLOCK ASSOCIATES September, 2001