Patent Application
20100065058
The present invention relates generally to a full face respirator mask, and specifically to such a mask for use in contaminated environments where there may be toxic materials present in the air.
For example, such full face respirator masks may be used by firefighters, military or any industry where a clean supply of air is necessary since the surrounding environment may be contaminated with toxic materials. In addition to supplying this clean air supply, the full face respirator mask also provides a seal around the entire face with a flexible facepiece to protect both the eyes and the face from the potentially harmful environment. This type of full face mask typically includes a transparent face shield forming a lens member and provision for either replaceable filter cartridges so as to filter out contaminants in the surrounding air, or alternatively may include a threaded connector to provide for means for accepting a supply of air from a clean source such as an air canister. The mask also would include an exhalation port so that expelled air can pass out of the mask into the surrounding air.
The full face respirator mask may also include a nose cup provided around the nose and mouth area of the user to assist in directing the flow of input air into and out of the face mask. The nose cup also assists in directing the expired air through the exhalation port, thereby reducing the buildup of carbon dioxide within the mask, and also preventing fogging of the facemask lens.
It is also desirable to provide as large a size for the lens member as possible, so as to increase the visual range of the wearer when viewing through the mask. For example, various attachment devices or connecting devices that form separate portions can sometimes impinge on the size of the lens member of the mask. It is therefore desirable to reduce or if possible eliminate some of the traditional connecting members. It would also be desirable to minimize as much as possible the structure of the mask by eliminating unnecessary members and to simplify the manufacture of the mask. It would therefore be desirable to incorporate within the lens member itself as much as possible the various connecting portions that cooperate with the filter cartridges or canister or any other means for providing connections to the mask of a clean supply of outside air.
The present invention incorporates a number of unique features that simplify the construction of the mask and reduce the cost while maintaining a lightweight versatile full face respirator mask. The features include a central exhalation area of the lens member that integrates an exhalation valve and a connector portion, generally referred to as a DIN screw connector, as an integral part of the overall molded lens member. The prior art typically has a separate member that is attached to the lens in a central position with a gasket seal. Applicants' unique integrally molded lens member makes it possible to dispense with the prior art additional interchangeable parts and have one model of mask that is adaptable to a variety of components such as supplied air from a single central cartridge or powered air, both through the central DIN connector. By incorporating this integrally molded structure, and specifically the exhaust valve mount and the DIN connector into the molded lens, these features are achieved with a number of benefits. These benefits include no added cost of separate parts, no cost to inventory additional parts and no associated labor to install the separate parts. Also, there is no risk of air leakage from the gasket seal.
As indicated above, the face mask also includes a nose cup to assist in directing the flow of air into and out of the face mask. When used in conjunction with the DIN threaded connector to an outside air supply, the prior art typically uses a separate air deflector part added to the assembly hub of the threaded fitting. The deflector's purpose is to deflect and guide incoming air towards air ports inside the mask. In addition, a separate part featuring the air ports may be required with the prior art masks. In the present invention, the air deflector and air ports are incorporated in the molded structure of the nose cup so that both features can be achieved with the following benefits: no added cost of separate parts, no cost to inventory the additional parts and no associated labor to install the parts.
In the prior art, typically, the lens member and the surrounding flexible facepiece are held together securely using a screw-together plastic clamp yoke. In the present invention, the rubber-like face seal forming the flexible facepiece is overmolded directly to the lens member to provide for a strong adhesive bond between the two parts. Normally, this would not be possible, since the lens member of the prior art typically has a scratch resistant surface coating of a silicone based material. The silicone based material prevents the adhesive bond.
The present invention incorporates a different material for the scratch resistance coating that is deposited on the surface of the lens. This material provides for the scratch resistance that is typically achieved with silicone, and this material is unique to Applicants' structure. This material allows for the overmolding to achieve the desired adhesive bond. The scratch resistant material that is used in the present invention is melamine based to allow for the overmolding and provide for the adhesion between the facepiece and the lens member. This simplified overmolded structure for the facemask provides for the following benefits: no added cost of clamp and screw hardware, no cost to inventory these parts and no associated labor to install the parts.
Although there have been facemasks which do incorporate overmolding, these facemasks do not use unique lens member of the present invention. Also, these facemasks do not use the melamine based coating to provide for scratch resistance and yet still allow for the overmolding of the facepiece to the lens member. In addition to the use of the melamine based coating, Applicants' invention also may incorporate mechanical means to further increase the adhesive bond between the flexible facepiece and the lens member. These mechanical means may include a textured outer edge to increase the surface area between the facepiece and the lens member and an undercut at the edge of the lens member to produce a shelf for the flexible face piece to rest against to resist forces that could separate the facepiece from the lens member. The textured outer edge may be produced by etching, such as plasma or chemical etching or abrading by mechanical grinding.
A clearer understanding of the present invention will be had with reference to the following description and drawings as well as the appended claims at the end of the application.
a) is a cross sectional view of the mask taken along lines (a)-(a) in
As shown in
As can be seen in further detail in
If the filter canisters (50) are used for the supply of intake air, then the intake ports (22) may be closed off with plugs (24), as shown in
In addition to the above ports (22) and (26), the port area (20) also includes an exhalation port (30). Air that is exhaled by the wearer therefore can exit through the exhalation port (30), and with the proper valve member insuring that no air would enter through the exhalation port (30). This valve member can be seen in more detail in
As can be seen in the drawings, the lens member (12) is integrally molded to include the central port area (20) of the lens, which integrates an exhalation valve port (30) and a connector port (26). The connector (26) is typically formed as a screw connector generally referred to as a DIN screw connector. All of these structures are integrally formed and integrated as part of the overall lens member. This integrated design allows for the integrally molded lens member to eliminate additional interchangeable parts, and to have one model of respirator mask that is adaptable to other components to provide supplied air through twin side canisters, powered air through a central connector or supplied air through a single central cartridge. In other words, the port (26) can be used to receive powered air, or could be used to receive air through a central single cartridge (52) shown in
In some types of respirators, the use of the DIN connector may not be necessary. The connector (26) may then be closed off by a plug. Alternately, the connector (26) may be eliminated and the area integrally formed with the rest of the lens member (12) as a solid surface.
All of this integrated structure provides for a very versatile design for the respirator mask. This integrated structure allows for all of the features to be achieved without the added cost of separate parts, and thereby the elimination of the need to inventory and manufacture these additional parts. This integrated structure also provides for the ability to have all the parts integrally molded as part of the lens member, so that there is no need to have additional labor to attach parts together. This integrated structure further eliminates the risk of air leakage from a sealing mechanism that would normally incorporate a gasket to seal these additional parts within the rigid lens.
As shown in
The front of the nose cup (34) therefore, is located immediately behind the central port area (20) of the lens member (12) and the nose cup (34) has portions that complement those integrated portions of the central port area (20). For example, the nose cup includes an opening (40) that corresponds with the exhalation valve port (30) of the lens member. In addition, to help lock the nose cup in position within the lens (12), openings (42) in the nose cup fit over corresponding pins (44) integrally molded as part of the lens member (12).
The nose cup (34) also includes air intake ports (46) located on both sides of the cup at an upper position. Also, slotted air intake ports (48) are located within the forward flange portion (36), but behind the area where the flange (36) fits over the corresponding inner flange (38) of the lens member. The openings (46) serve as air intake inhalation ports and each would typically incorporate a flap member in the interior portion of the nose cup to form a button type valve. This allows for the inhalation of air located within the lens member of the respirator mask to be directed to the nose and mouth of the wearer.
Typically the operation of the respirator mask would be as follows. Assuming the arrangement where the front opening (26) is closed off with the plug (28), and air enters the mask through the side ports (24) fitted with filter canisters (50). The intake air would pass through the filter canisters fitted to the openings (24), and through the openings (24) to the interior of the lens member and up the sides of the lens member and through the openings (46) that form inhalation valves and into the nose cup. The intake air may now be inhaled by the wearer. Exhaled air would exit directly through the opening (40) in the nose cup and through the exhalation valve (30) in the lens portion (12).
Alternatively, the openings (24) may be closed as shown by the plugs (24) in place in
As can be seen in the above structure, the nose cup does not incorporate a separate air deflector that is usually provided for in the prior art structures. The deflector (54) is incorporated within the nose cup itself to deflect and guide the incoming air towards the air ports (48) that are incorporated within the nose cup. All of these features are therefore achieved with no added cost for separate parts, no cost to inventory additional parts, and no associated labor to install these parts.
As can be seen in
Normally it would not be possible to overmold the flange to the lens member, since the lens member typically has a scratch resistant surface coating of a silicone material that prevents a strong adhesive bond between the two parts. The present invention, however, includes the use of a different surface coating to provide for the scratch resistance that is typically achieved with silicone. Applicants specifically provide for the use of a melamine based thermoformable scratch resistant coating, an example of which is manufactured by Film Specialties, Inc. under the trademark “FormGard™.” The melamine based material provides for the scratch resistance but still allows for a strong adhesive bond between the overmolded flange and the lens member.
In addition to the use of the melamine based material, the strong adhesive bond between the flange and the lens is also enhanced by the use of a shelf portion (56) located around the circumference of the lens. This shelf portion may be further undercut at position (58) and provide for a further bond to prevent the flange from being pulled off the lens. Also, the lip portion (56) surrounding area may have a rougher textured surface (60) to provide for a greater surface area and adhesion between the overmolded flange and the lens. The textured surface (60) may be produced by etching, such as plasma or chemical etching or abrading by mechanical grinding.
Although the invention has been described with reference to particular structure, it will be appreciated that various adaptations and modifications may be made and the invention is only to be limited by the appended claims.
