WO2009109770A1

WO2009109770A1 - An improved respirator

Info

Publication number: WO2009109770A1
Application number: PCT/GB2009/050137
Authority: WO
Inventors: Alan Wright; Michael Gibbons
Original assignee: Alpha Solway Limited
Priority date: 2008-03-06
Filing date: 2009-02-12
Publication date: 2009-09-11
Also published as: EP2249928A1; GB0804140D0

Abstract

The present invention provides a respirator comprising a body (12) at least partially formed from a filter media,and aretaining strap (14) attached to the body(12). The body (12) has a sealing edge (28) extending about the perimeter thereof.The body (12) comprises a fold line (32) extending across the body (12)and dividing the body (12) into first and second portions. An upper portion of the body(12)includes a nose bridge cavity (30) having a pair of resilient protrusions (54) adapted, in use, to secure the body (12) to the nose of a user. The respirator may therefore be folded substantially flat and does not need a clip to secure the body to the nose of a user.

Description

AN IMPROVED RESPIRATOR

The present invention relates to the field of respirators which an individual can fit over their nose and mouth in order to filter out harmful substances from the surrounding air.

Disposable respirators are known in the art and commonly comprise a mask moulded from a suitable filter media and an elasticated strap having an end connected either side of the mask with which to hold the mask in place. Additionally, these known respirators typically include a metal or plastic clip intended to shape the nose portion of the mask about the bridge of the nose of the user so as to ensure a sealing fit which prevents harmful airborne substances slipping through any gaps between the mask and the user's face. Such respirators provided a simple filtration solution but were inconvenient as they took up storage space on account of their pre-moulded shape. A solution was presented to this storage problem by creating a disposable respirator which could be stored virtually flat prior to use. Such respirators are known as "fold flat" respirators and are intended to provide the same filtration benefits as a conventional disposable respirator but without taking up as much storage space, either in an individual's pocket or a store cupboard. In order to allow the respirators to be folded flat, a transverse seam or fold line was provided across the body so that the mask could be easily flattened and stored.

Achieving a tight, sealing fit between a conventional disposable respirator and the nose area requires that the nose clip is bent so as to pinch the nose bridge. This means that the nose clip can be a source of discomfort to the wearer of the respirator. In addition, in the case of fold flat respirators, the nose clip limits where the seams or fold lines can be placed to achieve the flat storage of the mask. Furthermore, the rigidity of existing disposable respirators can be weakened during use as the warm breath of a user condenses on the inside of the filter media. This causes the filter media to become damp, which can lead to the collapse of the filter. Such a collapse could lead to gaps being created in the seal between the respirator and the face of the user, which could potentially allow harmful substances in through the gaps.

It is an aim of the present invention to obviate or mitigate one or more of these disadvantages.

According to the present invention, there is provided a respirator comprising: a body at least partially formed from a filter media, the body having a sealing edge extending about the perimeter thereof; and a retaining strap attached to the body; wherein an upper portion of the body includes a nose bridge cavity having a pair of resilient protrusions adapted, in use, to secure the body to the nose of a user; and the body comprises a fold line extending across the body and dividing the body into first and second portions.

The fold line may be a substantially longitudinal fold line extending down the body from the nose bridge cavity.

The body may be formed entirely from the filter media.

The respirator may further comprise a reinforcing mesh covering the exterior of the body. The reinforcing mesh may include a fold line corresponding to the fold line of the body. The reinforcing mesh may be formed from a moulded thermoplastics material. The reinforcing mesh may be bonded to the sealing edge of the body. Further portions of the body may be bonded to the reinforcing mesh. The bonding of the reinforcing mesh to the body may be achieved by ultrasonic welding.

The respirator may further comprise at least one valve means attached to one of the first and second portions of the body.

The fold line of the reinforcing mesh divides the mesh into first and second portions. One or both of the first and second portions of the reinforcing mesh may be adapted to receive the valve means thereon.

The respirator may further comprise first and second attachment lugs projecting from the opposing sides of the body, wherein respective ends of the strap are attached to the attachment lugs.

The attachment lugs may each include first and second apertures for receiving the strap. The strap may be threaded through the first and second apertures such that a portion of the strap extending between the first and second apertures of each lug is located on the exterior of the respirator, and a further portion of the strap extends between the first and second attachment lugs. The remote ends of the strap may include attachment means for attaching the remote ends to one another. The attachment means may be a snap fixing.

The nose bridge cavity may include a cushioning layer. The nose bridge cavity may include a seal.

A preferred embodiment of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 shows a front view of a respirator;

Figure 2 shows a rear view of the respirator of Figure 1 ; and

Figure 3 shows a side view of the respirator of Figures 1 and 2.

Figures 1 -3 illustrate a respirator, generally designated 10, in accordance with the present invention. The respirator is preferably a disposable respirator, which is intended to be disposed of after a single use.

The respirator 10 comprises a body 12 formed from a suitable filter media and a retaining strap 14 for securing the respirator to the head of a user. First and second attachment lugs 16,18 are formed either side of the body 12. The first attachment lug 16 includes first and second attachment apertures 20,22, while the second attachment lug also has first and second attachment apertures 24,26. The attachment apertures receive portions of the strap 14 in order to form the loop which will fit behind the head of a user, as will be described below.

The body 12 has a sealing edge 28 which extends around the entire perimeter of the body 12. The sealing edge 28 is adapted such that it will form a seal between the respirator 10 and the face of a user when in use. The body 12 is also provided with a contoured nose bridge cavity 30, which is best seen in Figure 2. A fold line 32 extends across the body 12, dividing it into first and second portions and allowing the respirator 10 to be folded substantially flat for storage or transportation. Preferably, the fold line 32 extends substantially longitudinally from the top of the body 12 at the nose bridge cavity 30 to the bottom of the body. However, in an alternative arrangement, the fold line 32 could instead extend across the body in a substantially transverse fashion, as represented by the dotted line 32' in Figure 1. The respirator 10 can optionally also include a reinforcing mesh 34 which covers the exterior of the body 12. In order to ensure that the respirator will still fold substantially flat, the mesh 34 includes a fold line which corresponds to that of the body 12. In the illustrated embodiment, the mesh 34 includes a support member 36 in which the fold line 32 is incorporated. The support member 36 extends across the respirator 10 and divides the mesh 34 into two portions. The reinforcing mesh 34 is preferably moulded from a suitable thermoplastic material and, where the support member 36 is present, the mesh 34 and support member 36 are integrally formed. One of the two portions of the mesh 34 may also have a solid disc (not shown) integrally formed therein. The disc portion can include identification information to allow a user to determine what filtration capabilities the particular respirator has, and therefore what application(s) it is suitable for. The reinforcing mesh 34 is bonded to the external surface of the body 12 adjacent the sealing edge 28. The mesh 34 can also be bonded to further portions of the external surface of the body 12 to further strengthen the attachment between the mesh 34 and body 12. The bonding is preferably achieved by ultrasonic welding of the mesh 34 to the body 12.

The nose bridge cavity 30 of the body 12 is best shown in Figure 2. The cavity 30 is located in the uppermost portion of the body 12 and extends upwards to form a generally n-shaped lip 50 at the top of the body 12. As shown in Figure 3, the cavity 30 projects forwards from the lip 50 into the body 12.

Referring again to Figure 2, the portions of the sealing edge 28 on either side of the body 12 immediately below the cavity 30 are at least partially convex. These convex portions of the sealing edge 28 form a pair of resilient protrusions 54 which contact either side of a user's nose when the respirator is in use. These resilient protrusions 54 ensure a sealing fit between the respirator 10 and the nose bridge of a user and secure the body to the nose when in use. The respirator therefore has no need of any form of clip to hold the respirator against the nose bridge. Optionally, a cushioning layer 52 can be provided inside the cavity 30 to add further comfort to the user.

The retaining strap 14 may be elasticated. During assembly of the respirator 10, the strap 14 is threaded through the first and second apertures 20,22 of the first attachment lug 16 so that the strap is located on the external surface of the lug 16, as best seen in Figure 1. The strap 14 is then threaded through the first and second apertures 24,26 of the second attachment lug 18 so that the strap 14 is also located on the external surface of the second lug 18. This threading of the strap 14 creates a loop portion extending between the two sides of the respirator

10 which can then be fitted behind the head of a user to obtain a sealing fit of the respirator to the user's face. Once the strap 14 has been threaded through the lugs 16,18 in the manner described, co-operating male and female fixtures 38,40 can be attached to either end of the strap 14 if desired. The fixtures 38,40 can snap together to form a second loop of the strap which can further improve the fit of the respirator to the user.

The present invention provides a respirator with a number of advantages over prior art respirators. Firstly, as it includes a nose bridge cavity the respirator of the present invention removes the need for a plastic or metal nose clip. This improves the comfort of the respirator on the wearer without compromising the seal around the nose area. A nose clip also limits where the fold line of the body can be located, as the clip will inhibit the folding of the respirator if it passes across the fold line. Removing the need for a nose clip also removes this limitation. The reinforcing mesh also provides the present invention with an advantage in that it supports and reinforces the filter media without limiting the fold flat capabilities of the respirator. Thus, the present invention avoids the potential for collapse of the filter media but takes up no more storage space in a pocket or cupboard.

The preferred embodiment of the respirator shown in the figures may optionally include an exhalation valve for certain applications. The valve can be located on either of the first and second portions of the body defined by the fold line therein. Where required, the valve can be attached to the body in a conventional manner. If the reinforcing mesh layer is present the solid disc formed in the mesh is punched out and the valve is fitted into the opening created by the removal of the disc. The identification information normally provided on the disc can instead be provided on the valve so that the capabilities of the respirator are still immediately evident to a user.

The body may be partially formed from a suitable filter media, or it may alternatively be entirely formed from the filter media. The filter media is preferably one of a number of conventional filter media materials and will be selected depending upon the intended end use for the respirator. If operating conditions demand it, the body may be formed from a filter media having electrostatic properties.

Whilst the respirator of the present invention is preferably disposable, it may be used repeatedly in certain applications. Whether the respirator may be used repeatedly will depend upon the airborne substance(s) that will be encountered during its use, the filter media selected for the body and the associated safety legislation. The optional reinforcing mesh is preferably made from a thermoplastic material that is bonded to the body using ultrasonic welds. However, the mesh may also be formed from alternative materials such as, for example, metal wire or a woven or non-woven fabric material. These alternative materials may be bonded to the body using a suitable adhesive.

Each of the convex portions of the sealing edge which provide the resilient protrusions may be supplemented with a support pad fitted to each portion so as to extend further into the nose bridge cavity. Alternatively, the convex portions of the sealing edge may be replaced with substantially straight edge portions and the support pads may then themselves act as the resilient protrusions. The cushioning layer in the nose bridge cavity can either be replaced by, or supplemented with, a seal to still further improve the sealing fit between the respirator and user.

The retaining strap may be non-elasticated. In this case, the strap may include slidable adjustment member for adjusting the length of the retaining strap.

These and other improvements and modifications can be incorporated without departing from the scope of the invention.

Claims

CLAIMS:

1. A respirator comprising: a body at least partially formed from a filter media, the body having a sealing edge extending about the perimeter thereof; and a retaining strap attached to the body; wherein an upper portion of the body includes a nose bridge cavity having a pair of resilient protrusions adapted, in use, to secure the body to the nose of a user; and the body comprises a fold line extending across the body and dividing the body into first and second portions.

2. The respirator of claim 1 , wherein the fold line is a substantially longitudinal fold line extending down the body from the nose bridge cavity.

3. The respirator of either preceding claim, further comprising at least one valve means attached to one of the first and second portions of the body.

4. The respirator of either claim 1 or claim 2, further comprising a reinforcing mesh covering the exterior of the body.

5. The respirator of claim 4, wherein the reinforcing mesh is formed from a moulded thermoplastics material.

6. The respirator of claim 5, wherein the reinforcing mesh is bonded to the sealing edge of the body by ultrasonic welds.

7. The respirator of any of claims 4 to 6, wherein the reinforcing mesh has a fold line corresponding to that of the body.

8. The respirator of claim 7, further comprising at least one valve means attached to one of the first and second portions of the body, wherein the fold line of the reinforcing mesh divides the mesh into first and second portions, and one or both of the first and second portions of the reinforcing mesh may be adapted to receive the valve means thereon.

9. The respirator of any preceding claim, wherein the nose bridge cavity includes a cushioning layer formed therein.

10. The respirator of any preceding claim, wherein the nose bridge cavity includes a seal therein.