WO1999046007A1

WO1999046007A1 - Face mask

Info

Publication number: WO1999046007A1
Application number: PCT/AU1999/000125
Authority: WO
Inventors: Goran Berndtsson; Lennart Beckman
Original assignee: Safety Equipment Australia Pty. Ltd.
Priority date: 1998-03-09
Filing date: 1999-03-02
Publication date: 1999-09-16
Also published as: AUPP222798A0

Abstract

This invention concerns a face mask of the type that is used with breathing apparatus. These masks either cover the entire face of wearer (full-face masks), or just the nose and mouth (half-masks). The mask comprises a tubular body having an opening at the back for connection to an air pipe and an opening at the front to fit a wearer's face. The front opening is finished with flange which is continuous around the perimeter of the opening and forms the cross-piece of a 'T', the tubular body forming the stem of the 'T'.

Description

Title

Face Mask

Technical Field

This invention concerns a face mask of the type that is used with breathing apparatus. These masks either cover the entire face of a wearer (full-face masks), or just the nose and mouth (half-masks).

Background Art

Breathing equipment is often associated with a face mask that seals against a wearers face to create an air-tight passageway between the equipment and the wearer. The mask is usually made of some elastomeric material with a thin highly flexible extension around the periphery which is pressed against the face. The extension is distorted to conform to the contours of each individual face and the material of the extension ensures a seal is made.

A positive air pressure (slightly greater than atmosphere) may be maintained in the mask while the equipment operates. During exhalation the pressure within the mask is increased. The positive pressure has the effect of pushing the mask away from the wearer's face, the increase in pressure during exhalation causes the mask to lift further, and if the high pressure gets under the extension it can lead to a break in the seal between the wearer's face and the mask. Other types of breathing apparatus may maintain a low pressure in the mask, the effect is similar with this type of equipment.

Summary of the Invention

The invention is a face mask for use with positive or negative air pressure breathing apparatus, comprising a tubular body having an opening the back for connection to an air pipe and an opening at the front to fit a wearer's face, the front opening is finished with flange which is continuous around the perimeter of the opening and forms the cross-piece of a "T", the tubular body forming the stem of the "T". The flange may be narrower at the top where it passes across the bridge of the nose and down the sides of the face, and thicker at the bottom where it passes over the chin.

The flange extends transverse to the direction of the tubular body and is connected to the tubular body at a point between its inward and its outward edges. As a result the flange is able to flex in a rotational sense about the point of connection, in both directions.

The mask may be a half-mask. The half-mask also has the advantage that the tubular body may have a relatively small dimension, allowing the wearer to wear goggles or spectacles over the top of the mask.

Brief Description of the Drawings

An example of the invention will now be described with reference to the accompanying drawings, in which: Figure 1 is a pictorial view of a half-mask;

Figure 2 is a vertical section through the mask of Figure 1; and Figure 3 is a horizontal section through the mask of Figure 1. The same reference numbers have been used throughout the drawings to refer to corresponding features.

Best Modes for Carrying out the Invention

Half-mask 1 comprises a tubular elastomeric body 2, having an opening 3 the back for connection to an air pipe and an opening 4 at the front to fit a wearer's face. The front opening 4 is finished with an integral inwardly and outwardly extending flange indicated generally at 5, and which is continuous around the perimeter of the opening 4.

The flange 5 is narrower at the top 6 where it passes across the bridge of the nose and down the sides of the face, and thicker at the bottom 7 where it passes over the chin. However, all around the perimeter of the opening 4 the flange 5 provides a broad width for contact with the face.

The flange extends transverse to the direction of the tubular body 2 and is connected to the tubular body at a point 8 between its inward 9 and its outward 10 edges. As a result the flange is able to flex in a rotational sense about the point of connection 8, in both directions. When the mask is donned the flange rotates about the point of connection 8 to fit the wearer's face. During exhalation a pressure increase is created within the mask. The high pressure tends to push the mask away from the face. However, it also has the effect of pushing the part of the flange that extends inwardly, more firmly against the face, so preventing separation between the mask and the face.

Although the invention has been described with reference to positive air pressure breathing apparatus, it should be appreciated that it may equally be applied to negative air pressure breathing apparatus.

It will be appreciated by persons skilled in the art that numerous variations and/or modifications may be made to the invention as shown in the specific embodiments without departing from the spirit or scope of the invention as broadly described. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive.

Claims

1. A face mask for use with positive or negative air pressure breathing apparatus, comprising a tubular body having an opening the back for connection to an air pipe and an opening at the front to fit a wearer's face, the front opening is finished with flange which is continuous around the perimeter of the opening and forms the cross-piece of a "T", the tubular body forming the stem of the "T".

2. The face mask according to claim 1, where the flange is narrower at the top where it passes across the bridge of the nose and down the sides of the face, and thicker at the bottom where it passes over the chin.

3. The face mask according to claim 1 or 2, where the mask is a half- mask.