AU2005211519A1 - Check valve for footwear - Google Patents

Description

Regulation 3.2 Revised 2/98

AUSTRALIA

Patents Act, 1990

ORIGINAL

COMPLETE SPECIFICATION TO BE COMPLETED BY THE APPLICAP NAME OF APPLICANT: ACTUAL INVENTOR: ADDRESS FOR SERVICE: INVENTION TITLE: DETAILS OF ASSOCIATED PROVISIONAL APPLICATION NO: Geoffrey Richard Davey Geoffrey Richard Davey Peter Maxwell and Associates Level 6 Pitt Street SYDNEY NSW 2000 CHECK VALVE FOR FOOTWEAR 2004 905 409 20 September 2004 Australia The following statement is a full description of this invention including the best method of performing it known to me:m:\docs\20051 047\085666.doc This invention relates to check valves and more particularly to a check valve adapted to selectively cover vents which are formed in footwear, particularly military footwear.

Footwear, notably military boots are known to have vents formed in the side walls above the interior of the sole. These vents allow moisture to pass out of the interior of the footwear. These vents are often provided in the way of grommets, which grommets may include a central screen. While these vents or grommets allow moisture to exit the footwear, they also allow moisture to enter the footwear.

According to one aspect of the invention there is provided a check valve for an opening in a boot or shoe comprising a tubular portion adapted to be inserted in the opening, a locking portion at one end of the tubular portion adapted to engage the inner periphery of the opening and a valve portion at the other end of the tubular portion adapted to engage the outer periphery of the opening, the valve portion having one or more slits therethrough which constitutes a valve, the arrangement being such that external pressure applied to the exterior of the valve portion forces the slit or slits together to form a seal and internal pressure applied to the interior of the valve portion opens the slits to provide a passageway from the interior of the boot or shoe to the exterior.

In a preferred embodiment, the valve is in the form of a resilient dome comprising three or more flexible segments which join to form a seal.

According to another aspect of the invention there is provided a boot or shoe incorporating a check valve as defined above.

In order that the invention may be more readily understood and put into practical effect, reference will now be made to the accompanying drawings in which:- 13/09/2005 Fig. 1 is a top plan view of a valve according to one embodiment of the present invention; Fig. 2 is a cross-sectional view of the valve shown in Fig. 1, Fig. 3 is a cross-sectional view of the valve shown in Fig. 2 installed in a boot in its closed position, and Fig. 4 is a cross-sectional view of the valve shown in Fig. 2 installed in a boot in its open position.

As shown in Figs. 1 and 2, a check valve 10 for a grommet of a shoe or boot comprises a polymeric cap or cover 11 into which is formed an arrangement of flexible flaps or segments 12 which are defined by slits 13. In the example depicted in Figs 1 and 2, the slits 13 are moulded into the cap or cover 11. As shown better in Fig. 2, the cap or cover 11 is generally dome shaped. There may be three or more slits 13 so as to form three or more flaps or segments 12. The particular example of Fig. 1 depicts essentially four slits 13 which intersect at a common point 14. The arrangements of slits 13 therefore appears as a cross and defines four identical flaps or segments 12.

It can be seen from Fig. 2 that the slit 13 extends completely through the thickness of the dome 11 although the slit is wider at the exterior surface than at the interior surface 21.

As shown in Fig. 2, the valve 10 has an inner flange 22 which is connected to the cover or dome 11 by tube 23 having peripheral gripping corregations 24. The flange 22 has an inwardly directed circumferential barb adapted to engage the interior of a boot as will be described below. The cover or dome 11 has an inner circumferential planar face 15 adapted to engage the exterior of a boot as will be described below.

In this instance, the valve is made from butyl or noverstine rubber but may be made of any convenient resilient material. The diameter of the cover 13/09/2005 or dome 11 is 12 mm, the diameter of the inner flange 22 is 10 mm, the length of the connecting tube 23 is 5 mm and the overall length of the valve is 7 mm.

The valve 10 is designed so that it can be retrospectively fitted to existing boots already in service. In the case of combat boots, the existing wire gauze ferrules in the arch are removed and the inner flange 22 is forced through the aperture in the boot and finally the valve 10 assumes the disposition shown in Figs 3 and 4 with the planar face 15 of the cover or dome 11 against the outside 30 of the boot and the barb 25 against the inner surface 31 of the boot and the corregations 24 sealing against the periphery of the aperture.

The valve 10 is shown in its normal disposition in Fig. 2. As shown in Fig. 3, pressure by water or air on the outside of the boot that is on the outside of the cover or dome 11 will flatten the dome and force the segments 12 together therefore closing the slits and hence the valve.

As shown in Fig. 4, pressure within the boot will force the segments 12 apart to open the valve.

As will be apparent from the foregoing description, the check valve functions by resiliently distorting under pressure so that the flaps or segments 12 distort in the direction of the arrows in Fig. 4. The pressure required to distort the flaps 12 is generated from the interior of the shoe or boot during normal walking so that liquid water contained within the shoe or boot flows in the direction of the arrows 42 from the interior of the shoe or boot to the exterior. When the pressure generated by walking or foot movement ceases, the memory characteristics of the polymer from which the valve is formed act to restore the flaps or segments 12 to their initial or resting position shown in Fig.

2.

13/09/2005 In this way, liquid water is prevented by virtue of the check valve 10 from entering the interior of the shoe or boot in significant quantities and yet the check valve 10 permits water trapped within a shoe or boot to be ejected by internal pressure. The check valve 10 is understood to be easily inserted into the aperture which previously held the wire gauze ferrule and requires no adhesives or special tools for insertion or removal.

Various modifications may be made in detail of design and construction of the valve without departing from the scope or ambit of the invention.

13/09/2005

Claims (9)

1. A check valve for an opening in a boot or shoe comprising a tubular portion adapted to be inserted in the opening, a locking portion at one end of the tubular portion adapted to engage the inner periphery of the opening and a valve portion at the other end of the tubular portion adapted to engage the outer periphery of the opening, the valve portion having one or more slits therethrough which constitutes a valve, the arrangement being such that external pressure applied to the exterior of the valve portion forces the slit or slits together to form a seal and internal pressure applied to the interior of the valve portion opens the slits to provide a passageway from the interior of the boot or shoe to the exterior.

2. A check valve according to claim 1 wherein the valve portion is in the form of a resilient dome comprising three or more flexible segments having slits therebetween.

3. A check valve according to claim 2 wherein the valve portion has an inner circumferential planar face adapted to engage the exterior of the boot or shoe around the outer periphery of the opening.

4. A check valve according to claim 2 wherein there are four flexible segments and four slits which intersect at a common point.

A check valve according to claim 1 wherein the locking portion comprises an outwardly extending annular barb adapted to engage the inner periphery of the opening. 13/09/05

6. A check valve according to claim 1 wherein the tubular portion has peripheral gripping corrugations on its outer surface adapted to engage the periphery of the opening.

7. A check valve for an opening in a boot or shoe substantially as hereinbefore described with reference to the accompanying drawings.

8. A boot or shoe incorporating a check valve according to any one of the preceding claims.

9. A boot or shoe substantially as hereinbefore described with reference to the accompanying drawings. Dated this 13 day of September 2005 Geoffrey Richard Davey Patent Attorneys for the Applicant PETER MAXWELL ASSOCIATES 13/09/05