Description A Filtering Mask Technical Field

The present invention relates to a filtering mask. The present invention is in the sector of individual protection devices destined to the protection of the breathing passages, e.g. dust-proof masks, half- masks, full face masks, filters, isolators, respirators, self-contained breathing apparatuses and breathable air circuits.

Background Art

As is well known, filtering masks have a structure made of a material that is permeable to air and at the same time is able to retain one or more harmful substances and/or particles.

Generally, the structure of the filtering masks defines, at least when worn, a space for housing users' facial area corresponding to their breathing passages, i.e. to the mouth and nose. Once a filtering mask is worn, both mouth and nose are isolated from the surrounding environment, so the inhaled air is forced to flow through the filtering material constituting the structure of the mask itself. Undesired substances and/or particles are then retained by the structure of the filtering mask without reaching the user's breathing passages.

Among the various filtering masks on the market, filtering masks are known whose structure is fundamentally constituted by the three portions: a front portion, which in use normally resides in front of the breathing passages of the user who wears them, and two lateral portions that develop transversely from

the central portion to form the aforementioned housing compartment. A first lateral portion is engaged to engage users' nasal septum and cheekbones, whilst a second lateral portion is destined to engage their chin in such a way as to circumscribe their breathing passages within the housing compartment. The central and lateral portions are usually defined by distinct parts, appropriately joined together by means of seals, seams or any other junction or coupling element suitable for the connection of the aforesaid parts.

The masks are also provided with at least one elastic engagement harness, which can be elongated to the back of the neck to assure its stable position on users' face. Normally, the elastic harness engages opposite ends of the central portions by means of respective additional elements that are suitably kept fastened by means of sealing, sewing or similar joining system.

With reference to the air filtering masks described above, the Applicant has observed that they are not free from some drawbacks, and they can be improved in several aspects, mainly in relation of their adaptability to users' face, to the air-tightness of the mask when it is worn, and to their comfort and ease of wear.

In particular, the Applicant has observed to known masks adapt poorly to users' facial conformation, especially at the nasal septum. The adaptability problems of the aforesaid masks inevitably impinge on their filtering capabilities because, during users' respiration, the inhaled air flows through gaps defined between the masks and the users' face, invading the housing compartment to involve, subsequently, users' breathing passages. This phenomenon tends to nullify the filtering properties of the masks which thus do

not serve their purpose even though they are worn.

In the attempt to overcome the drawback of air-tightness, it is a common practice to put the elastic harness under excessive tension to press the mask against users' face in search of an optimal adhesion. However, this practice entails a high pressure of the mask against the user's face, causing annoying discomfort without assuring the optimal air-tightness of the housing compartment.

Disclosure of Invention An object of the present invention is to solve the aforementioned problems.

An additional object of the invention is to propose a filtering mask that is able to engage users' face in an optimal manner.

Another object of the invention is to devise a filtering mask that is completely isolated from the surrounding environment.

A further object of the present invention is to propose a comfortable mask that causes no discomfort or pain to users' face.

The technical task set out above and the specified objects are substantially achieved by a filtering mask comprising the characteristics set out in the characterising part of claim 1.

Description of the Drawings

Additional characteristics and advantages will become more readily apparent from the detailed description of a preferred, but not exclusive

embodiment, of a filtering mask, in accordance with the present invention. The description will be provided below with reference to the accompanying figures, provided purely by way of non limiting indication, in which: figure 1 is a perspective view from the exterior of an air filtering mask, in accordance with a first embodiment of the present invention; figure 2 is a perspective view of the mask of figure 1, shown from the interior; figure 3 is a perspective view from the exterior of an air filtering mask, in accordance with a second embodiment of the present invention; figure 4 is a perspective view of the mask of figure 3, shown from the interior; figure 5 is a perspective view of an air filtering mask, in accordance with a third embodiment of the present invention; figure 6 is a perspective view of the mask of figure 5, shown from the interior; figure 7 is a perspective view of an air filtering mask, in accordance with a fourth embodiment of the present invention; figure 8 is a perspective view of the mask of figure 7, shown from the interior; figure 9 is a section of a detail of the mask of figures 5 through 7, taken along the trace IX-IX of figure 5; figure 10 is a section representation of the same detail shown in figure 9, represented according to a fifth embodiment of the present invention.

Description of the Illustrated Embodiment

With reference to the accompanying figure, the number 1 indicates, in its entirety, a filtering mask in accordance with the present invention.

As shown in the accompanying figures, the mask 1 has at least one structure 2 made of an air permeable to air and impermeable to at least one harmful particles present in the air. In particular, the structure 2 is preferably made of a yielding and soft multi-layer filtering material, e.g. non-woven or

"melt-blown" fabric.

Advantageously, the structure 2 is obtained in a single piece or block provided and junction lines define the overall shape of the mask 1 both in non operative or folded condition (not shown), in which the mask 2 has portions that are mutually superposed according to a substantially flattened shape, and in operative or open position, in which the mask defines at least one housing compartment 3 (figures 2, 4, 6 and 8) adapted to receive a facial area corresponding to a user's breathing passages, i.e. nose and mouth.

In particular, the structure 2 presents at least one front portion 4 able to be positioned at least partially in front of the user's nose and mouth when the mask is in operating condition. The front portion 4 has a flattened and elongated development, tapered at respective opposite ends 4a. As shown in figures 1, 3, 5 and 7, the ends 4a of the front portion 4 have respective terminal edges 4b folded in such a way as to remain superposed to the structure of the front portion 4. The terminal edges 4b are also fastened on the structure of the front portion 4 by means of respective junction points 4c (figures 1, 3, 5 and 7), preferably seals, to define respective engagement slots 5 through

which extends at least one elastic holding harness 6 engageable to the user's head. In other words, the elastic holding harness 6 is associated to the mask 1 without any additional elements or components by means of the terminal edges 4b folded and fixed on the structure of the front portion 4. With reference to figures 1, 3, 5 and 7, the harness has two terminal ends

6a, provided each with a respective connecting structure 6b which concur in defining a buckle for fastening the mask 1 on the user's head. As shown in the figures from 1 to 8, the structure 2 has a first lateral portion 7 extending transversely from a first peripheral edge 4d of the front portion 4 and a second lateral portion 8 extending transversely from a second peripheral edge 4e of the front portion 4, opposite to the first peripheral edge 4d.

As shown in figures 1, 3, 5 and 7, the first lateral portion 7 comprises at least one central area 9 that yields, preferably elastically, to adapt itself to the conformation of the user's nasal septum and two lateral filtering area 10 engaged to the central area 9 from respectively opposite parts.

Always with reference to figures 1, 3, 5 and 7, the central area 9 of the first lateral portion 7 has two lateral ends 9a developing transversely to the front portion 4. Preferably, each lateral end 9a of the central area 9 and the respective lateral area 10 lie on superposed planes. In detail, each end 9a of the central area 9 develops underneath the respective lateral area 10. An example of said configuration is visible from the solution shown in the section of figure 9.

Advantageously, the central area 9 and the lateral areas 10 of the first lateral portion 7 are preferably fastened by means of appropriate seal lines 11

extending along the development of the lateral ends 9a of the central area 9.

Again with reference to figures 1, 3, 5 and 7, the central area 9 of the first lateral portion 7 extends between the first peripheral edge 4d of the front portion 4 and a free edge 7a of the first lateral portion 7, opposite to the first peripheral edge 4d. The central area 9 of the first lateral portion 7 also has a front edge 9b that engaged, preferably by sealing, the first peripheral edge 4d of the front portion 4 of the mask 1. Advantageously, the central area 9 of the first lateral portion 7 is made of a spongy and impermeable material (figures 5 through 8), preferably made of synthetic resin, elastomer or techno-polymer foam. However, the central area 9 may be made of different materials from the aforementioned one, permeable or impermeable to air, and yielding to adapt to the conformation of the user's nasal septum and face.

Again with reference to figures 1, 3, 5 and 7, the first lateral portion 7 of the mask 1 is provided with at least one adapter element 12 whose structure is advantageously deformable to adapt itself and to adapt the central area 9 to the conformation of the user's nasal septum.

In particular, the structure of the adapter element 12 has an elongated conformation in which is identified a central portion 12a and respective opposite ends 12b. In accordance with the embodiments illustrated in figures 1 and 3 both the central portion 12a of the adapter element 12 and the lateral portions 12b thereof lie according to a position superposed to the central area 9 of the first lateral portion 7.

In accordance with the embodiments illustrated in figures 5 and 7, the

central portion 12a lies according to a position superposed to the central area 9 of the first lateral portion 7, whilst the opposite ends 12b of the adapter element are fastened respectively to the lateral areas 10 of the first lateral portion 7. As shown in figures 5, 7 and 9, the ends 12b of the adapter element 12 are advantageously incorporated in the structure of the respective lateral areas 10 of the lateral portion 7.

Advantageously, as shown in the embodiments shown in figures 1 and 3, the central area 9 of the first lateral portion 7 is covered by a thin veil or layer 9c permeable to air, preferably made of non woven fabric, which is coupled to the same central area 9 by sealing or any other similar junction system to the edges of the lateral portion 7. Preferably, the veil 9c covers the adapter element 12 maintaining it above the central area 9 of the first lateral portion 7.

In the solution shown in figures 1 and 3, the veil 9c completely covers both the central area 9 which the adapter element 12 associated thereto. With reference to the solution of figure 10, the veil 9c is preferably joined in a single piece to the structure of the lateral portions 10 of the lateral portion 7 of the mask 1. In this case, the opposite ends 12b of the adapter element 12 are fastened respectively to the lateral areas 10 of the first lateral portion 7 to be advantageously incorporated in the structure of the respective lateral areas 10. Again with reference to figure 10, both the lateral filtering areas 10 and the central area 9 of the first lateral portion 7 are covered by a thin veil or layer 10a permeable to air, preferably made of non woven fabric, which is coupled by sealing or any other similar junction system to the edges of the lateral portion 7. In other words, as shown in figure 10, the end 12b of the adapter element 12 are

fastened to the lateral filtering areas 10 remaining underneath the covering veil or layer and above the central area 9.

Advantageously, as shown in figures 2 and 4, at least one protection element 12c, preferably a spongy band, is internally engaged to the first lateral portion 7 of the structure 2, at the adapter element 12, to protect the user's nasal septum therefrom.

In accordance with the embodiments shown in figures 6 and 8, the mask 1 is advantageously provided with sealing means 13 associated to at least one internal part of at least one of the lateral portions 7, 8 of the structure 2 to engage a respective area of the user's face when the mask 1 is in operative condition. More in particular, the sealing means 13 maintain the mask 1 in a stable position when the latter is engaged on the user's face, avoiding any relative sliding.

As shown in figures 6 and 8, the sealing means 13 comprise a first sealing sheath 14 which extends internally to the housing compartment 3 at least along the free edge 7a of the first lateral portion 7.

According to said configuration, the first sealing sheath 14 is adapted to engage a respective area of the user's face substantially related to the nasal septum and to the cheekbones. As shown in figures 6 and 8, the first sealing sheath 14 is preferably associated to the central area 9 of the first lateral portion 7 and advantageously engages the lateral areas 10 thereof.

Again with reference to figures 6 and 8, the first sealing sheath 14 has a covering portion 14a joined to the central area 9 of the first lateral portion 7

internally to the housing compartment 3 and designed to lie on the user's nasal septum.

To maintain the characteristics of elasticity of the central area 9 of the first lateral portion 7, the covering portion 14a of the first sealing sheath 14 is separated from the body of the sheath. In this way, the covering portion 14a is able to deform together with the central area 9 when the mask is worn by the user.

In accordance with the embodiments shown in figure 8, the sealing means

13 further comprise a second sealing sheath 15 which extends, internally to the housing compartment 3, at least along a free edge 8a of the second lateral portion 8, opposite to the second peripheral edge 4e of the front portion 4, to engage a respective area of the user's face relating substantially to the chin.

Advantageously, the sealing means 13 are deformable to adapt to the superficial conformation of the area of the face to be engaged and to define, at the respective engagement area, an air-tight barrier to isolate the housing compartment 3 from the surrounding environment.

As shown in figures 6 and 8, the sealing means 13 have a substantially laminar structure and are made of a material with high friction coefficient to remain on the user's face in the engagement position assigned to it. Advantageously, the sealing means 13 are made of a material impermeable to air, preferably made of elastic foam material, to prevent air from transiting between the mask 1 and the user's face during respiration.

In accordance with the embodiments shown in figures 3, 4, 6 and 8, the mask 1 comprises at least a through opening 16 obtained through the front

portion 4, whereat is positioned at least one valve 17 for regulating the air flow during the user's respiration. Preferably, the valve 17 is a one-way valve, switchable by effect of the user's respiration, between a first condition, in which it occludes the through opening 16 (figures 4 and 8) so that the inspired air flows through the filtering structure 2 of the mask 1, and a second condition, in which the expired air is free to flow through the through opening 16.

In detail, the one-way valve 17 comprises at least one grid 18 (figures 4 and 8) located at the through opening 16, at least one external case 19 (figures 3 and 7) extending peripherally from the through opening 16 and defining at least one containment chamber (not shown) at least one membrane 20 (figures 4 and

6) operatively located within the case 19. The membrane 20 is advantageously laid on the grid 18 when the valve 17 is in the first condition, occluding the through opening 16, and disengages at least partially from the grid 18 when the valve 17 is in the second condition, allow the transit of air through the through opening 16 from the interior to the exterior.

The present invention solves the problems observed in the prior art and achieves the proposed objects.

First of all, the object of the present invention allows and excellent insulation of the housing compartment from the exterior. In particular, the presence of the sealing means determines an optimal adherence between the inner surfaces of the housing compartment and the user's skin, preventing the undesired entry of unfiltered or polluted air, especially during the inspiration phase of the user's respiration.

It should also be added that the central area 9 of the first lateral portion 7

significantly shields the user's nasal septum from the adapter element providing the mask with particular ease of wear and comfort.

The spongy and impermeable material whereof the central area is made enables the optimal coupling of the mask with any goggle whilst preventing them from fogging over, as is normally the case in the presence of a permeable material that is commonly subject to moisture.

Being interposed between the sealing means and the adapter element, the central area 9 of the first lateral portion 7 also allows a significant tensioning of the elastic retaining harness 6 which can be tightened more without hurting the user, thereby also increasing the adaptation of the mask 1 to the conformation of the user's face.